• Journal of the Korean Society of Food Culture
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• v.7 no.4
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• pp.329-338
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• 1992

This study was attempted aimed to prepare of Andong sikhe by pure culture inoculation and to improve storage stability by the addition of stabilizers to the product. Lactobacillus delbreuckii was selected for pure culture inoculation in the fermentation. The effect of stabilizers on the sedimentation, sensory evaluation and viscosity of Sikhe were investigated during the fermentation of traditional Andong Sikhe stored at $4^{\circ}C$ Morphological characteristics of Sikhe were determined by scanning electromicrograpy. Among the stabilizers added to the traditional Andong sikhe Na-alginate was found to be best stabilizers. When the product was evaluated by the sensory panel, the addition of stabilizers up to 0.1% level actually increased the acceptability of the product, while the concentration of more than 0.2% stabilizers affected the acceptability of the negatively. Sikhe added Na-carboxymethyl cellulose and Na-alginate showed highest viscosity on the 2nd day of fermentation, while homogenized Andong sikhe with Carrageenan showed the highest peak in viscosity on the first day of fermentation. Lactic acid bacterial count reached to $3.2{\times}10^8/ml$ after 20 days of storage. The surface and cross section of rice was observed by scanning electron microscope. As the fermentation proceeded holes on the surface increased, and nearly empty cell wall remained at the later stage of fermentation. Use of pure cultured inoculum of L. delbreuckii supported the rapid build up of the lactic acid bacteria and consequently the whole process of the fermentation was shortened. The acceptability and product quality were improved by use of L. delbreuckii inoculum.

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.190-197
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• 2013

Three slime-forming lactic acid bacteria were isolated from traditional Korean fermented soy sauce and soybean paste and shown to produce exopolysaccharides (EPS) in sucrose media. By isolating the strains, examining their morphological characteristics and determining their 16S rDNA sequences, N58-5 and K6-7 were identified as Leuconostoc mesenteroides and N45- 10 as Leuconostoc citreum. The acid and bile tolerances of these three strains were investigated. Amongst the three lactic acid bacteria, Leuc. citreum N45-10 exhibited the highest viability ($10^5-10^6$ CFU/ml) in 0.05 M sodium phosphate buffer (pH 0.3) for 2 h, in artificial gastric juice for 2 h and in 0.3%, 0.5% oxgall for 24h. Leuc. mesenteroides K6-7, N58-5 and Leuc. citreum N45- 10 were grown in sucrose liquid medium and 8.16 g/L, 3.65 g/L, 16.17 g/L of EPS was collected, respectively. The hydrolyzed EPS was analyzed by HPLC in order to determine the sugar composition of EPS. Leuc. mesenteroides K6-7 and N58-5 showed two peaks indicating glucose and fructose, thus they were determined to be hetero-type polysaccharides. Leuc. citreum N45-10 showed only the glucose polymer, indicating it to be a homo-type polysaccharide. In addition, all three lactic acid bacterial hemolysis did not demonstrate a clear zone in blood agar in the area surrounding a lactic acid bacteria colony.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11B
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• pp.980-990
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• 2004

In this paper, we propose the dynamic bandwidth allocation algorithm for the IEEE802.3ah Ethernet Passive Optical Network(EPON) system to provide the fairness among terminals, and evaluate the delay-throughput performance by simulation. For the conventional EPON systems, an Optical Line Termination (OLT) schedules the upstream bandwidth for each Optical Network Unit (ONU), based on its buffer state. This scheme can provide a fair bandwidth allocation for each ONU. However, it has a critical problem that it does not guarantee the fair bandwidth among terminals which are connected to ONUs. For an example, we assume that the traffic from a greedy terminal increases at a time. Then, the buffer state of its ONU is instantly reported to the OLT, and finally the OW can get more bandwidth. As a result, the less bandwidth is allocated to the other ONUs, and thus the transfer delay of terminals connected to the ONUs gets inevitably increased. Noting that this unfairness problem exists in the conventional EPON systems, we propose a fair bandwidth allocation scheme by OLT with considering the buffer state of ONU as welt as the number of terminals connected it. For the performance evaluation, we develop the EPON simulation model with SIMULA simulation language. From the result of the throughput-delay performance and the dynamics of buffer state along time for each terminal and ONU, respectively, one can see that the proposed scheme can provide the fairness among not ONUs but terminals. Finally, it is worthwhile to note that the proposed scheme for the public EPON systems might be an attractive solution for providing the fairness among subscriber terminals.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.492-504
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• 2018

This study was conducted to investigate the effects of seaweed peeling (SP), glycolic acid peeling (GP) and general scrub (GS), which are widely known as cures for acne in both medicine and esthetics on the keratosis pilaris skin and provide basic data for a keratosis pilaris improvement program. For the experiment, subjects were categorized into control (GS) and experimental (GP and SP) groups, and tests were performed on arms and legs with relatively high keratosis pilaris symptoms (5 parts for each group) for 6 weeks. The keratin quantity, sebum content, moisture level and pigmentation were measured before and after (2, 4 and 6 weeks) the experiment and comparatively analyzed. The GP group showed an increase in moisture level (t=-4.064, p<0.01) but a decrease in pigmentation (t=3.536, p<0.01), while a decrease in keratin quantity (t=2.370, p<0.05) and pigmentation (t=4.017, p<0.01) was observed in the SP group and a decrease in keratin quantity (t=2.834, p<0.05) and an increase in moisture level (t=-7.589, p<0.001) was observed in the control group (GS). Additionally, the skin irritation reaction was lowest in the GS group. The SP group had the highest satisfaction with the improvement in response to keratosis pilaris care. When asked if they were willing to get the treatment with the same product, both SP and GP groups were high. In other words, keratosis pilaris care was needed in both experimental and control groups. Overall, the results of this study indicate that SP, GP and GS, which are commonly used in remedying acne, normalize turnover cycle by removing the dead cells from around the pores and improve keratosis pilaris symptoms by increasing moisture in the skin. Therefore, to improve keratosis pilaris skin, it is important to keep removing keratin and using a moisturizer that provides a skin barrier on a regular basis. The results presented herein will be useful as basic data for a keratosis pilaris improvement program.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.61-69
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• 2009

Statement of problem: Porcelain veneers have become a popular treatment modality for aesthetic anterior prosthesis. Fitting porcelain veneers in the mouth usually involve a try-in appointment, which frequently results in salivary contamination of fitting surfaces. Purpose: An in vitro study was carried out to investigate the effect of silane treatment timing and saliva contamination on the resin bond strength to porcelain veneer surface. Material and methods: Cylindrical test specimens (n=360) and rectangular test specimens (n=5) were prepared for shear bond test and contact angle analysis. Whole cylindrical specimens divided into 20 groups, each of which received a different surface treatment and/or storage condition. The composite resin cement stubs were light-polymerized onto porcelain adherends. The shear bond strengths of cemented stubs were measured after dry storage and thermocycling (3,000 cycles) between 5 and $55^{\circ}C$. The silane and their reactions were chemically monitored by using Fourier Transform Infrared Spectroscopy analysis (FTIR) and contact angle analysis. One-way analysis of variance (ANOVA) and Dunnett's multiple comparison were used to analyze the data. Results: FT-IR analysis showed that salivary contamination and silane treatment timing did not affect the surface interactions of silane. Observed water contact angles were lower on the saliva contaminated porcelain surface and the addition of 37% phosphoric acid for 20 seconds on saliva contaminated porcelain increased the degree of contact angle. Silane applied to the porcelain, a few days before cementation, resulted in increasing the bond strength after thermocycling. Conclusion: Within the limitation of this study, it can be concluded that it would be better to protect porcelain prosthesis before saliva contamination with silane treatment and to clean the contaminated surface by use of phosphoric acid.

• Journal of Embryo Transfer
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• v.19 no.3
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• pp.245-255
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• 2004

In recent years, an increasing number of studies on pig in vitro maturation(IVM) and in vitro fertilization(IVF) have been separated. the wide range of new technologies, including that in applied molecular genetics, has increased this interest. the production of viable porcine embryos in vitro is a prerequisites for the successful production of transgenic pigs to date. The efficiency of IVM/IVF techniques in the porcine is lower than that obtained in other species such as cattle and mouse. The several problems are generally thought to be the cause of poor results: the low rate of MPN formation derived from inadequate IVM of oocytes, the high incidence of polyspermy after IVF and cell blocking at 4 cell during embryos culture. For there reasons overcoming, many studies have been conducted to improve in vitro embryo-genic competence of oocytes. In the last several years, many maturation culture media have been evaluated and various exogenous factors such as hormones and grows factors have been tested to improve the efficiency of porcine in vitro system. In the study several antioxidants have been examined to improve in vitro fertilization and development of porcine oocytes. In this study, several antioxidants were examined to determine the effects on the development of oocytes to the cleavage, morula and blastocyst stage when added at the maturation(IVM) or in vitro fertilization(IVF) or in vitro culture(IVC) of porcine embryos. Porcine oocytes were matured, fertilized and embryos were cultured in defind conditioned medium in vitro with or without supplementation with the antioxidents of cysteine, catalase and glutathione. 1. Significant improvement of blastocyst rate (27.2％ versus 15.4％, p<0.05) were achieved when catalase(500U/$m\ell$) were added to TCM-199 medium and morula rate(72.0％ versus 53.9％, p<0.05) were significantly higher when glutathione(1.0mM/$m\ell$) were added to TCM-199 medium than those of control. 2. In mTBM medium for oocytes fertilization, the addition of cysteine, catalase and glutathione had no positive effect on embryonic development. glutathione had no positive effect on embryonic development. In conclusion, this study shows that addition of catalase, gluththione during IVM improved the rate of porcine embryo development.

• Journal of Oriental Neuropsychiatry
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• v.15 no.2
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• pp.149-158
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• 2004

만성적이거나 반복적인 스트레스는 우울중이나 심신병 등의 발병 기전과 밀접한 관련이 있다. 전기적 자극(electric foot shock), 한랭 자극, 속박(immobilization), 투쟁(fighting), 에테르 노출 등과 같은 심한 스트레스 자극이 뇌 조직의 시상 및 시상하부, 편도체 등에서의 노르아드레날린(noradrenalin) 방출을 유의 하게 감소시키는 동시에 혈청 corticosterone을 증가시키는 것으로 알려져 있다. 한의학에서는 스트레스 인자에 대한 신체반응을 기(氣)의 변화로 인식하고 있고, 이러한 자극요인들은 신체에 대하여 병적 요인을 제공하여 제반 질환을 야기한다. 또한 질병 발생에 대한 근거로 정기(正氣)와 사기(邪氣)의 상호 관계 위주로 인식하는데, 내부의 기(氣)의 변조(變調)는 질병의 발생을 야기하는 기초가 된다. 실험에 사용된 연근(蓮根)은 연꽃과에 속한 수생초본인 연꽃의 뿌리부분으로 우(藕) 또는 우절(藕節)이라는 명칭으로 불리기도 한다. 성미(性味)는 감(甘) 삽(澁) 평(平) 무독(無毒)하고 폐(肺) 위(胃) 간경(肝經)으로 들어가며 수렴지혈(收斂止血) 화어(化瘀)의 효능이 있어 토혈(吐血) 객혈(喀血) 뇨혈(尿血) 편혈(便血) 등의 각종 출혈 증상에 사용되어져 왔다. 최근 연꽃의 부위별 추출물이 흰쥐의 지질 과산화 생성을 효과적으로 억제하는 것으로 보고되고 있어 연근(蓮根)에 대한 다양한 약리 효능의 검색이 필요할 것으로 생각되며 연꽃의 씨앗인 연자육(蓮子肉)이 양심안신(養心安神)의 효능이 있어 스트레스성 질환에 많이 응용되고 있는 것에 착안하여 본 연구를 착수하였다. 실험 동물은 ICR계 마우스를 이용하였으며, 사회 심리적 스트레스는 옆쪽 cage에서 다른 마우스의 신체에 가해지는 전기 충격을 하루 1시간 동안 지켜보게 하는 것으로 유발하였으며 이 상태에서 약물을 투여한 그룹을 실험군, 그렇지 않은 그룹을 대조군으로 하였다. 정상군은 아무런 자극 없이 하루 1시간 동안 일정 공간에 가두어 두는 것으로 하였다. 실험 결과 사회 심리적 스트레스를 받은 경우에 아무런 처치를 하지 않은 대조군에 비해 연근 추출물을 100mg/kg/day 용량으로 5 일간 투여한 실험군에서 혈청 중 corticosterone 함량이 유의하게 감소하였으므로 매우 효과적으로 스트레스를 해소하였음을 알 수 있다. 뇌세포 중에서 신경전달물질로 분비되는 노르아드레날린의 분비량은 전반적으로 증가되는 경향을 나타내었으나 유의성은 없었다. 신체적 또는 사회 심리적 스트레스가 간 조직 내 지질의 과산화를 유발하는 것으로 나타났으며 연근 추출물이 이 결과에는 영향을 주지 못하였다. 사회 심리적 스트레스로 인하여 간 조직 내 지질과산화 정도가 증가하였으므로 혈청 내 ALT 함량도 따라 증가할 것으로 추정되었으며 이에 대한 연근 추출물 경구 투여가 간 조직을 보호할 수 있는지를 확인하기 위해 분리한 혈청으로부터 ALT 함량을 측정한 결과 대조군에 비하여 유의한 감소를 나타내었다. 또한 연근 추출물이 혈청 내 지질 과산화물의 생성을 억제할 수 있다면 질병의 예방과 치료에 효과적일 것으로 추정할 수 있으므로 그 생성량을 측정하여 보았으나 대조군과의 차이가 나타나지 않았다. 이상의 결과들을 종합하여 보면 스트레스가 부하된 5일 동안 연근(蓮根) 추출물을 함께 투여한 결과 혈청 corticosterone 함량을 유의하게 감소시켰고 뇌 조직내 noradrenaline 함량을 증가시키는 경향을 나타내어 스트레스 해소에 도움이 될 수 있음을 시사하였다. 또한 혈청 내 ALT 함량을 유의하게 감소시켜 스트레스로 인해 발생하는 간 기능의 손상도 어느 정도 억제시키는 것을 확인할 수 있었는데 앞으로 연근(蓮根)의 이러한 작용에 대한 보다 자세한 연구들이 필요한 것으로 생각된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.4
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• pp.326-335
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• 1988

In order to increase the availability of filefish scrap, the ordinary and low salt sauce were prepared, and identified their taste compounds in their products. To process the filefish scrap sauce, chopped filefish scrap was mixed with koji, 25% brine, slat and glucose (25.0 : 65.0 : 12.5 : 7.0, w/w) and fermented at $25{\pm}4^{\circ}C$ for 120 days. The same process was also carried out to process the low salt sauce adding sorbitol, lactic acid and ethyl alcohol (7.0 : 0.7 : 9.0. w/w) instead of salt. While amino nitrogen and volatile basic nitrogen(VBN) of products were decreased, pH and reducing sugar were increased all alone the fermentation period. The major free amino acids of products at final stage of fermentation were glutamic acid, alanine, leucine, lysine and aspartic acid. And the contents of total amino acid in the ordinary and low salt sauce were 4126.6(mg/100m1 sauce), 4519.5(mg/100m1 sauce) after fermentation. Hypoxanthine was revealed as the major constituent among nucleotides and their related compounds through fermentation. Free amino acid-N in the filefish scrap sauces were from 56.3%(ordinary) to 60.7%(low salted) of extractive nitrogen. From the sensory evaluation, the quality of products from filefish scrap sauce were almost equal to sold soy sauce on the market.

• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1497-1502
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• 2002

Purpose : We evaluated allele frequencies and distribution of surfactant protein A1(SP-A1) in Korean neonates in order to estimate prevalence of RDS to find out new SP-A alleles, and to establish new steroid therapy. Methods : Genomic DNA was extracted from 100 neonates and served as a template in PCR for genotype analysis. SP-A gene-specific amplications and gene-specific allele determinations were performed using PCR-RFLP methods. Results : The distribution for the alleles of the SP-A1 gene in the study population were 6A, $6A^2$, $6A^3$, $6A^4$, $6A^8$, $6A^9$, $6A^{10}$, $6A^{11}$, $6A^{12}$, $6A^{13}$, $6A^{14}$, $6A^{15}$, $6A^{16}$, $6A^{17}$, $6A^{18}$, $6A^{20}$. The specific frequencies for the alleles of the SP-A1 gene in the study population were : $6A^2=21%$, $6A^3=45%$, $6A^4=11%$, $6A^8=9%$, $6A^{14}=8%$. Conclusion : The frequency of $6A^3$ was higher than the other SP-A1 alleles in Korean neonates. This finding suggests that the prevalence of RDS in Korea may be low compared with other countries. However, this finding also suggests that Korean neonates have a high risk of infection.

• Clinical and Experimental Pediatrics
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• v.53 no.4
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• pp.532-537
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• 2010

Purpose : Early postoperative arrhythmias are a major cause of mortality and morbidity after open heart surgery in the pediatric population. We evaluated the incidence and risk factors of early postoperative arrhythmias after surgery of congenital heart disease. Methods : From January 2002 to December 2008, we retrospectively reviewed the medical records of the 561 patients who underwent cardiac surgery in Kyungpook National University Hospital. We analyzed patients' age and weight, occurrence and type of arrhythmia, cardiopulmonary bypass (CPB) time, aortic cross clamp (ACC) time, and postoperative electrolyte levels. Results : Arrhythmias occurred in 42 of 578 (7.3%) cases of the pediatric cardiac surgery. The most common types of arrhythmia were junctional ectopic tachycardia (JET) and accelerated idioventricular rhythm (AIVR), which occurred in 17 and 13 cases, respectively. The arterial switch operation (ASO) of transposition of the great arteries (TGA) had the highest incidence of arrhythmia (36.4%). Most cases of cardiac arrhythmia showed good response to management. Patients with early postoperative arrhythmias had significantly lower body weight, younger age, and prolonged CPB and ACC times ($P$<0.05) than patients without arrhythmia. Although the mean duration of ventilator care and intensive care unit stay were significantly longer ($P$<0.05), the mortality rate was not significantly different among the 2 groups. Conclusion : Early postoperative arrhythmias are a major complication after pediatric cardiac surgery; however, aggressive and immediate management can reduce mortality and morbidity.