• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.4
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• pp.570-593
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• 1996

This study was intended to perform the influence of condyle positional change after surgical correction of skeletal Class III malocclusion after BSSRO in 20 patients(males 9, females 11) using computed tomogram that were taken in centric occlusion before, immediate, and long term after surgery and lateral cephalogram that were taken in centric occlusion before, 7 days within the period intermaxillary fixation, 24hour after removing intermaxillary fixation and long term after surgery. 1. Mean intercondylar distance was $84.45{\pm}4.01mm$ and horizontal long axis of condylar angle was $11.89{\pm}5.19^{\circ}$on right, $11.65{\pm}2.09^{\circ}$on left side and condylar lateral poles were located about 12mm and medial poles about 7mm from reference line(AA') on the axial tomograph. Mean intercondylar distance was $84.43{\pm}3.96mm$ and vertical axis angle of condylar angle was $78.72{\pm}3.43^{\circ}$on right, $78.09{\pm}6.12^{\circ}$on left. 2. No statistical significance was found on the condylar change(T2C-T1C) but it had definitive increasing tendency. There was significant decreasing of the distance between both condylar pole and the AA'(p<0.05) during the long term(TLC-T2C). 3. On the lateral cephalogram, no statistical significance was found between immediate after surgery and 24 hours after the removing of intermaxillary fixation but only the lower incisor tip moved forward about 0.33mm(p<0.05). Considering individual relapse rate, mean relapse rate was 1.2% on L1, 5.0% on B, 2.0% on Pog, 9.1% on Gn, 10.3% on Me(p<0.05). 4. There was statistical significance on the influence of the mandibular set-back to the total mandibular relapse(p<0.05). 5. There was no statistical significance on the influence of the mandibular set-back(T2-T1) to the condylar change(T2C-T1C), the condylar change(T2C-T1C, TLC-T2C) to the mandibular total relapse, the pre-operative condylar position to the condylar change(T2C-T1C, TLC-T2C), the pre-operative mandibular posture to the condylar change(T2C-T1C, TLC-T2C)(p>0.05). 6. The result of multiple regression analysis on the influence of the pre-operative condylar position to the total mandibular relapse revealed that the more increasing of intercondylar distance and condylar vertical axis angle and decreasing of condyalr head long axis angle, the more increasing of mandibular horizontal relapse(L1,B,Pog,Gn,Me) on the right side condyle. The same result was founded in the case of horizontal relapse(L1,Me) on the left side condyle.(p<0.05). 7. The result of multiple regression analysis on the influence of the pre-operative condylar position to the pre-operative mandibular posture revealed that the more increasing of intercondylar distance and condylar vertical axis angle and decreasing of condylar head long axis angle, the more increasing of mandibular vertical length on the right side condyle. and increasing of vertical lengh & prognathism on the left side condyle(p<0.05). 8. The result of simple regression analysis on the influence of the pre-operative mandibular posture to the mandibular total relapse revealed that the more increasing of prognathism, the more increasing of mandibular total relapse in B and the more increasing of over-jet the more increasing of mandibular total relapse(p<0.05). Consequently, surgical mandibular repositioning was not significantly influenced to the change of condylar position with condylar reposition method.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.845-849
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• 2010

A gold nanoparticles modified carbon paste electrode (GN-CPE) has been used for the determination of atenolol (ATN) in drug formulations by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronocoulometric methods. The results revealed that the modified electrode shows an electrocatalytic activity toward the anodic oxidation of atenolol by a marked enhancement in the current response in buffered solution at pH 10.0. The anodic peak potential shifts by -80.0 mV when compared with the potential using bare carbon paste electrde. A linear analytical curve was observed in the range of $1.96\;{\times}\;10^{-6}$ to $9.09\;{\times}\;10^{-4}\;mol\;L^{-1}$. The detection limit for this method is $7.3\;{\times}\;10^{-8}\;mol\;L^{-1}$. The method was then successfully applied to the determination of atenolol in tablets and human urine. The percent recoveries in urine ranged from 92.0 to 110.0%.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.295-299
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• 2004

The lacertid lizard Takydromus wolteri widely distributed in South Korea, but intraspecific diversity of this species was not almost studied. T. wolteri represented by 8 specimens collected from 5 localities were analyzed by the Randomly Amplified Polymorphic DNA (RAPD) method with 28 random decamer primers and the phenogram constructed by using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) method based on RAPD data. The populations of T. wolteri using in this paper were collected from Gyeonggi-do, Chungcheongbuk-do, Jeju-do, Jeollanam-do and Gyeongsangnam -do in South Korea. Among 68 different bands detected in RAPD analysis, 59 bands (87％) showed polymorphism. The phenogram showed that the populations of T. wolteri were grouped into two. These results suggest that T. wolteri were supported intraspecific diversity.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.235-247
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• 2020

The purpose of this study was to evaluate the skeletal and dentoalveolar effects and optimal timing for treatment of class II malocclusion with functional appliances in children and adolescents. A group of 30 patients with class II malocclusion were divided into 3 groups according to their use of functional appliance: Twin block, Activator, Fränkel appliance. The group was also divided into 2 groups according to the cervical vertebrae maturation method. Lateral cephalometric radiographs were analyzed pretreatment (T0) and posttreatment (T1). Among the functional appliances, treatment with Twin block and Activator showed significant increase in the length of the mandible (Co-Gn) and the lower anterior facial height (ANS to Me), whereas the overjet and overbite were significantly reduced. Treatment with Fränkel appliance showed significant improvement in the relationship of maxilla and mandible. In addition, if the functional appliance was used during the period of pubertal growth peak, there was a significant increase in mandibular length, improvement in the relationship of maxilla and mandible, labial inclination of lower incisors and decrease in overjet compared to the treatment before pubertal growth peak. Therefore, this study indicates that using functional appliances for patients with class II malocclusion is effective and the optimal timing for using functional appliances is during pubertal growth peak.

• Korean Journal of Ichthyology
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• v.10 no.1
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• pp.1-10
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• 1998

The early history of Korean mandarin fish, Siniperca scherzeri was studied to obtain some information required in aquaculture and reinforcement of natural population. During the period from June 1996 to July 1997, the mature adults of Siniperca scherzeri were collected from the middle Soyang Lake at Puksan - myon, Chunchon - shi, Kangwon - do, Korea. The eggs from females were obtained by injecting HCG or/and GnRH - a and fertilized by dry method in the laboratory. The fertilized eggs, measuring 1.70~2.10 mm in diameter and expanded to 2.20~2.66mm after absorption of water, were globosity, light orange yellow, separative, submergence and had one large oil globules of 0.5~0.7 mm. The blastodisc was formed in 1 hour and cleavage started in 1 hour 30 min. after fertilization, and the intervals of each stage of cleavage was about 50 min. at the water temperature of $21{\sim}24^{\circ}C$. Hatching occurred 131 hours 30 min. after fertilization and newly hatched larvae were 5.86~6.85 mm in total length(TL) and numerous stellate melanophores were distributed on the yolk and abdomen of caudal peduncle. The yolk was almost absorbed and the teeth development. 3 days after hatching, at 6.98~7.60 mm TL. The head spines and the teeth were largely developed and all fins were completely formed and became postlarva stage 15 days after hatching, at 10.10~12.90 mm TL. The body shape and the color pattern were similar to adult, 25 days after hatching, at 15.3~23.8 mm TL. In 5 months after hatching were reached at 154.10~175.02 mm TL and 49.32~82.67 g in body weight.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.3
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• pp.233-240
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• 1994

This study was conducted to compare the endocrine milieu, and pregnancy rates in In Vitro Fertilization and Embryo Transfer(IVF-ET) program employing combined with gonadotropin releasing hormone agonist(GnRH-a) and pergonal(LH 75lU+FSH 75lU) when either human chorionic gonadotropin(HCG) or progesterone were used for luteal phase support. A total number of 40 IVF-ET treatment cycles were prospectively studied. Ovarian hyperstimulation method was modified ultrashort protocol using GnRH-a. All patients started Decapeptyl at menstrual cycle day # 2, and HMG was started at # 3 days. When leading follicle was ${\geqq}$18mm or at least two follicles were ${\geqq}$14mm in diameter, HCG 10000lU intramuscularly was injected. After 36 hours HCG administration, oocytes were retrieved as usual guided by transvaginal ultrasound. Embryo were transfered 36-48 hours later. The patient's cycles were prospectively randomized to receive HCG(20cycles) or Progesterone (20cycles) for luteal support. The progesterone group received 25mg 1M starting from the day of ET. The HCG group received 1500IU 1M. on days 0, +2, +5 after ET. Estadiol($E_2$) and Progesterone($P_4$) were measured on the day of oocyte aspiration, ET day, and every 6 days thereafter. Results were follows as; 1. Estradiol, progesterone and LH levels on the day of HCG trigger, retrieved oocytes and number of transfered embryo were not significantly different in both groups. 2. On the day of aspiration and embryo transfered day, $E_2$, $P_4$ level were significantly higher in progesterone group than HCG group(p<0.01). 3. $E_2$, $P_4$ level on 6 days after ET were significantly higher in progesterone group than HCG group(p<0.01). But, $P_4/E_2$ ratio was not different in both groups. 4. $E_2$, $P_4$ level 12 days after ET were decreased abruptly in both groups and higher hormonal level appeared in HCG group(P<0.01). 5. The total pregnancy rate in the HCG group was 40% (8/20) and in the progesterone group 15%(3/20). 6. Comparing the pregnant and nonpregnant cases progesterone group was not different the hormonal status. In HCG group, pregnant cases appeared in higher $P_4$, $P_4/E_2$ ratio than nonpregnanct cases(P<0.01).

• Food Engineering Progress
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• v.15 no.4
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• pp.324-331
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• 2011

Hyperspectral reflectance imaging technology was used to predict internal quality of cherry tomatoes with the spectral range of 400-1000 nm. Partial least square (PLS) regression method was used to predict firmness, sugar content, and acid content. The PLS models were developed with several preprocessing methods, such as normalization, standard normal variate (SNV), multiplicative scatter correction (MSC), and derivative of Savitzky Golay. The performance of the prediction models were investigated to find the best combination of the preprocessing and PLS models. The coefficients of determination ($R^{2}_{p}$) and standard errors of prediction (SEP) for the prediction of firmness, sugar content, and acid content of cherry tomatoes from green to red ripening stages were 0.876 and 1.875kgf with mean of normalization, 0.823 and $0.388^{\circ}Bx$ with maximum of normalization, and 0.620 and 0.208% with maximum of normalization, respectively.

• Korean Journal of Veterinary Service
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• v.44 no.4
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• pp.227-237
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• 2021

Artificial insemination of Korean native cattle (KNC) is the predominant method for breed improvement. However, industrialization of embryo production and transfer is necessary to utilize the genetic potential of KNC. The aim of this study was to examine associations between KNC donor cows and ovum pick-up (OPU) conditions, in-vivo oocyte recovery, and embryo development. Oocyte recovery and blastocyst development rates were higher at 50 and 60 mmHg OPU vacuum pressure than at 40 mmHg, which was, however, not significant. Regarding follicle growth, injection of 500 ㎍ GnRH 36 hours before OPU significantly increased the number of OPU oocytes from an average of 4.6 to 7.6 (P<0.05); no significant difference in embryo development rates was observed. Significant differences were observed in the numbers of OPU oocytes, embryo development rates, and transplantable blastocysts per individual among nine KNC donors (P<0.05). Furthermore, although there was no difference in OPU oocyte recovery intervals in approximately 2~8 weeks, the number of recovered oocytes significantly decreased at the 12-week interval (P<0.05); there was no difference in embryo development rates. The number of oocytes and embryonic development rates only tended to decrease until the seventh OPU session, but decreased significantly until the eighth session (P<0.05). The average pregnancy rate after transfer of OPU-derived in-vitro embryos into recipient cows was 41.8%. To improve the efficiency of OPU egg recovery and in-vitro embryo production, considering KNC donor characteristics, vacuum pressure of 60 mmHg, GnRH pretreatment to induce follicle growth, and effective OPU egg recovery up to seven times at intervals of 2~4 weeks appears to be most suitable. This study may facilitate the industrialization of KNC embryo production and transfer using high-quality cows.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.170-173
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• 2007

Cooling characteristics of a liner were investigated by a film cooling method using a gas nitrogen in a rocket engine. High temperature gas of this test was made by mixing liquid nitrogen with combustion gas of a liquid rocket. A supply system of gas nitrogen was additionally constructed to the existing test facility of liquid rocket engine, and a new test section consisted of a liner and a gas injection ring was manufactured. A 10 second firing test for finding cooling characteristics of the liner was successfully conducted and liner surface temperatures and hot gas temperature was obtained.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.6
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• pp.617-621
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• 2013

This study examined the effect of electron-beam (E-beam) irradiation on the electrical properties of n-GaN, AlGaN and AlGN/GaN structures on sapphire substrates. E-beam irradiation resulted in a significant decrease in the gate leakage current of the n-GaN, AlGaN and HEMT structure from $4.0{\times}10^{-4}A$, $6.5{\times}10^{-5}A$, $2.7{\times}10^{-8}A$ to $7.7{\times}10^{-5}A$, $7.7{\times}10^{-6}A$, $4.7{\times}10^{-9}A$, respectively, at a drain voltage of -10V. Furthermore, we also investigated the effect of E-beam irradiation on the AlGaN surface in AlGaN/GaN heterostructure high electron mobility transistors(HEMTs). The results showed that the maximum drain current density of the AlGaN/GaN HEMTs with E-beam irradiation was greatly improved, when compared to that of the AlGaN/GaN HEMTs without E-beam irradiation. These results strongly suggest that E-beam irradiation is a promising method to reduce leakage current of AlGaN/GaN HEMTs on sapphire through the neutralization the trap.