• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.2
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• pp.428-435
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• 1997

For the purpose of investigating the continuous fluoride releasing from acrylic resin using removable appliances by incorporating fluoride into polymethylmethacrylate during the construction of the appliances, two kinds of fluoride were blended with acrylic powder and devided into five groups as follows. Group 1 : no fluoride (control) Group 2 : NaF 5 wt% Group 3 : NaF 10 wt% Group 4 : $CaF_2$ 5 wt% Group 5 : $CaF_2$ 10 wt% Resin specimens were tested in vitro for fluoride release with fluoride electrode and flexural strength with Instron. The results were as follows ; 1. After 24 hrs, released fluoride concentration(ppm) was the most in group 3($126.5{\pm}14.15$) then, next, group 2($49.5{\pm}4.92$), group 5($2.67{\pm}1.08$), group 4($0.81{\pm}0.30$), group 1($0.03{\pm}0.01$) in order, but after 28 days, group 3($3.37{\pm}0.31$), group 5($1.25{\pm}0.25$), group 4($0.74{\pm}0.19$), group 2($0.68{\pm}0.07$), group 1($0.03{\pm}0.01$). 2. Fluoride releasing of NaF groups were faster and more amount than $CaF_2$ groups initially but decreased significantly, later. 3. Flexural strength ($kg/cm^2$) was the biggest in group 1($602.90{\pm}69.32$), and then group 4($568.98{\pm}20.16$), group 5($556.19{\pm}5.26$), group 2($536.12{\pm}30.35$), group 3($508.44{\pm}26.16$) in order, the differences between control group and NaF groups were statistically significant (p<0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.57-64
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• 2010

The purpose of this investigation was to study the relationship between vertical facial pattern and dental maturation in children in pubertal and pre-pubertal periods. The material consisted of lateral head films and panoramic radiographs of 1306 patients. The subjects were selected according to Ricketts's VERT index and other including criteria. These subjects were divided by VERT index to brachyfacial group and dolichofacial group. In each selected subject, dental age was determined according to Demirjian's dental maturity score. All subjects were distributed according to age, vertical facial type and sex, mean and standard deviation of chronological age, dental age and age difference were determined in each group. And the data were analysed to find the difference of tooth maturation by facial pattern. Findings of this study include: 1. In all groups, dental age was determined higher than chronological age in statistically significant level. 2. Compared by vertical facial pattern, in pubertal age groups, it seems that subjects with brachyfacial type presented the tendency to have an advanced dental maturation, only in female group. 3. Compared by pubertal period, brachyfacial groups presented more advanced dental maturation in pubertal groups than pre-pubertal groups.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.4
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• pp.464-473
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• 2018

The purpose of this study was to investigate the distribution of eruption disturbance and to analyze its causes, treatment methods, and duration of orthodontic traction, based on 703 patients with eruption disturbance who were treated in the pediatric dental clinic of Seoul National University Dental Hospital between July 2011 and June 2016. Eruption disturbance in pediatric patients was most prevalent in the maxillary canine, followed by the maxillary central incisor and maxillary first molar. Eruption disorder of the maxillary canine was more common in females (p < 0.001), whereas the maxillary central incisor (p = 0.009), maxillary first molar (p < 0.001) and mandibular first molar (p = 0.028) were more common in males than females. The most common causes of eruption disturbance were abnormality of the eruption pathway and the presence of obstacles in the pathway. Orthodontic traction was the most prevalent treatment choice for eruption disorder, mostly done for the maxillary central incisors. The duration of orthodontic traction was shorter with younger age (p < 0.001) and lower crown position (p < 0.001). It is important for pediatric patients to detect eruption disorders early through regular checkup, and it is necessary to initiate treatment at an appropriate time with an accurate diagnosis and treatment plan.

• Journal of Aquaculture
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• v.21 no.1
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• pp.34-40
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• 2008

This study investigated the effect of rearing conditions on the spawning habit, juvenile growth and larvae development of Marphysa sanguinea, to develop techniques of its artificial seed production. M. sanguinea released trochophore larvae around the burrow when the water temperature was from $18^{\circ}C$ to $22^{\circ}C$. Larvae floated away after staying in the burrow for a while. Larvae secreted mucus eight days after release, covering their whole body with it, and developed ten somites 20 days after release. In preference of juveniles in different grain sizes of sediment, the highest survival rate was made in the grain substrate of $1{\sim}2$ mm in the mean diameter, but the lowest was in the $2{\sim}3$ mm grain substrate. Optimum growth was obtained at the rearing temperature of $24^{\circ}C$(SGR 1.10%), and it reached over $2{\sim}3$ times higher weight gain and specific growth rate than those reared at $21^{\circ}C(0.64),\;18^{\circ}C(0.56)$ and $15^{\circ}C$(0.42) for 50 days. Salinity also made a great difference in the growth and survival rate. The highest weight gain and growth rate were shown when the juveniles were reared at salinity 30 psu.

• Journal of Korea Port Economic Association
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• v.25 no.1
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• pp.87-106
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• 2009

This paper is intended to suggest benchmarking ascension for the Gwangyang Port as a hub for international logistics. Most countries that seek to join. and lead, the global trading system as they work to develop production and logistics systems that establish a reputation for leadership in international logistics. Our focus in this research is on the Gwangyang Port and whether Gwangyang Port is capable of carving out a competitive niche as a hub of international logistics. Our analysis is based on comparison and analysis with benchmark port developments around the world. As proposals to promote and activate Gwangyang Port as a hub for international logistics, we recommended in this paper several benchmarks. First, Gwangyang Port FTZ must strengthen the incentive system for tenant companies and providing an inducement for new global companies. Second, Gwangyang Port needs to moderation of regulation on the investment tenant companies and strengthening one-stop service. Third, it is required to stabilize labor and management relationship and securing of flexibility of labor market. Lastly, Gwangyang Port must strengthen mutual interaction of Free Economic Zone (FEZ), Customs Free Zone(CFZ) and Free trade Zone(FTZ) in Korea.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.3
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• pp.261-265
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• 2000

Objective: This study was performed to evaluate the influence of maternal age on embryo quality and the frequency of multiple pregnancy in IVF-ET program. Method: 86 conventional IVF-ET cycles were divided into three groups according to the age by 5 year (group A: 26-30, group B: 31-35, group C: 36-40 yrs). The in vitro fertilization and development outcome (fertilization, cleavage and high quality embryo rate) and the pregnancy outcome (pregnancy, implantation, G-sac/high quality embryo and multiple pregnancy rate) were examined. And then, these results were compared among the groups. Results: The rates of fertilization (62.7, 68.5 and 65.4%, respectively) and cleavage (95.6, 97.6 and 98.0%, respectively) were not different among the groups. And the high quality embryo (HQE) rate also was not different among the groups (61.8, 62.9 and 62.8%, respectively). The pregnancy rate of group C (23.3%) was significantly lower than that of group A (41.2%) and B (48.7%). And the implantation rate was significantly decreased with advance in maternal age (group A; 17.3%, B; 12.6% and C; 6.0%). The G-sac/high quality embryo rate was significantly higher in group A (70.8%) when compared to group B (32.2%) and C (40.0%). On the other hand, the multiple pregnancy rate was significantly lower in group C (14.3%) when compared to group A (71.4%) and B (36.8%). Conclusion: The pregnancy rate was significantly decreased over 35 years. The G-sac/HQE and multiple pregnancy rate were significantly high below 31 years. Thus, these results suggest that the number of high quality embryo transferred should be limited by the age and another criteria for embryo quality evaluation were required for single embryo transfer.

• Journal of Korean Medicine for Obesity Research
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• v.15 no.1
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• pp.9-23
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• 2015

Objectives: This study was investigated the improvement effects of Pakistani Ephedra herba-containing Gangji-hwan-1, 2, 3 (Di-fatty; DF-1, 2, 3), Chinese Ephedra herba-containing Gangjihwan-4 (DF-4) and combination of DF-1 and Gamisoche-hwan (GSH) on obesity in a high fat diet-fed obese mouse model. Methods: Eight-week-old C57BL/6N mice were divided into seven groups: a normal lean group given a standard diet, an obese control group given a high fat diet, and DF-1, 2, 3, 4, and DF-1+GSH groups given a high fat diet with DF-1, 2, 3, 4 (40, 80, 160, 80 mg/kg), and DF-1+ GSH (80 mg/kg), respectively. After 8 weeks of treatment, body weight gain, feeding efficiency ratio (FER), blood lipid markers, liver histology, and fat weight and histology were examined. Results: Body weight gain was significantly decreased in DF and DF-1+GSH groups compared with control. The extent of decreases was eminent in DF-1+GSH group. FER and circulating concentration of leptin were decreased in DF and DF-1+GSH groups compared with control. Circulating concentrations of triglyceride, glucose and insulin were decreased in DF and DF-1+GSH groups compared with control. The size of adipocytes were decreased by DF and DF-1+GSH groups compared with control, whereas the adipocyte number per unit area was increased by them, suggesting that DF and DF-1+GSH groups decreased the number of large adipocytes. Conclusions: In conclusion, these results suggest that DF and DF-1+GSH groups decrease FER, plasma leptin concentration, blood anti-obesity biomarkers and fat mass, improves body weight gain. In addition, these effects were more effective in DF-1+GSH combination group than in DF-1, 2, 3, 4 groups.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.3
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• pp.17-31
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• 2005

Purpose : These studies were undertaken to evaluate the effects of the administration of different concentrated Morindae officinalis Radix extract solution on the spermatogenic abilities such as concentration, motility and morphological normality of sperm from the testis and the activities of sperm hyaluronidase, testicular peroxidase and testicular catalase. Methods : We used the 2-month-old mice and administered the extract solution of Morindae officinalis Radix in the different concentration once a day for 60 days. The control group was administered the normal saline in the same way and duration. We examined the number of total, motile and normal sperm from the cauda epididymis, the activities of sperm hyaluronidase, testicular peroxidase and testicular catalase. Also we observed changes of isolated testis before and after administration of Morindae officinalis Radix extract solutions the mice. And we compared to the testicular tissue especially seminiferous tubules between control and treated group by histochemical methods. Results : The significant dose-dependent differences were observed in the concentration of total sperm, the motility and normality of spermatozoa of Morindae officinalis Radix extract solution administered groups compared to the control group, respectively. In the histological analysis of the testicular tissues, the enlargement of testicular lobe diameter and apparent vasculogenesis between testicular lobes were observed in the Morindae officinalis Radix extract solution administered groups compared to the control group, respectively. Also, the activity of hyaluronidase was significantly increased in the Morindae officinalis Radix extract solution administered groups compared to the control group. In the antioxidant activity analysis, the activity of testicular peroxidase was significantly increased in the Morindae officinalis Radix extract solution administered groups compared to the control group, respectively. Conclusion : This study shows that Morindae officinalis Radix has the beneficial effect on the concentration, morphology and motility of sperm, the activities of sperm hyaluronidase and testicular peroxidase. We can suggest that Morindae officinalis Radix extract solution be useful for the treatment of male sexual dysfunctions and infertility.

• Journal of Ginseng Research
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• v.44 no.1
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• pp.135-144
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• 2020

Background: Panax species are important herbal medicinal plants in the Araliaceae family. Recently, we reported the complete chloroplast genomes and 45S nuclear ribosomal DNA sequences from seven Panax species, two (P. quinquefolius and P. trifolius) from North America and five (P. ginseng, P. notoginseng, P. japonicus, P. vietnamensis, and P. stipuleanatus) from Asia. Methods: We conducted phylogenetic analysis of these chloroplast sequences with 12 other Araliaceae species and comprehensive comparative analysis among the seven Panax whole chloroplast genomes. Results: We identified 1,128 single nucleotide polymorphisms (SNP) in coding gene sequences, distributed among 72 of the 79 protein-coding genes in the chloroplast genomes of the seven Panax species. The other seven genes (including psaJ, psbN, rpl23, psbF, psbL, rps18, and rps7) were identical among the Panax species. We also discovered that 12 large chloroplast genome fragments were transferred into the mitochondrial genome based on sharing of more than 90% sequence similarity. The total size of transferred fragments was 60,331 bp, corresponding to approximately 38.6% of chloroplast genome. We developed 18 SNP markers from the chloroplast genic coding sequence regions that were not similar to regions in the mitochondrial genome. These markers included two or three species-specific markers for each species and can be used to authenticate all the seven Panax species from the others. Conclusion: The comparative analysis of chloroplast genomes from seven Panax species elucidated their genetic diversity and evolutionary relationships, and 18 species-specific markers were able to discriminate among these species, thereby furthering efforts to protect the ginseng industry from economically motivated adulteration.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.198-203
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• 2015

This study was performed to evaluate changes in the chemical composition of germinated rough rice with high hydrostatic pressure treatment (HPT). Rough rice was germinated at $37^{\circ}C$ over 6 days (control), and then subjected to HPT at 30 MPa for 24 h. The highest crude protein content was 9.54% in the control sample after 6 days of germination. Crude lipid content increased from 2.04-2.74% (control) to 2.27-3.10% (HPT). HPT samples showed higher values of total free sugar and glucose content than those of the control. The total amino acid value was not significant, but the essential amino acid content increased from 0.45-5.09 mg/g in the control to 1.57-5.30 mg/g in the HPT sample. The major fatty acids were found to be palmitic, oleic, and linoleic acid. The content of oleic acid decreases with HPT, whereas that of linoleic and linolenic acid increased slightly during the initial stages of germination. These results suggest that HPT after germination efficiently depolymerizes chemical components and enhances the content of essential nutrients.