• The Journal of Korean Academy of Prosthodontics
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• v.33 no.3
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• pp.584-609
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• 1995

The purpose of this study was to evaluate the difference of the galvanic corrosion behaviour of the titanium in contact with gold alloy, silva-palladium alloy, and nickel-chromium alloy using the immersion and electrochemical method. And the effects of galvallit couples between titanium and the dental alloys were assessed for their usefulness as materials for superstructure. The immersion method was performed by measuring the amount of metal elementsreleased by Inductivey coupled plasma emission spectroscopy(ICPES) The specimen of fifteen titanium plates, the five gold alloy, five silver-palladium, five nickel-chromium plates, and twenty acrylic resin plates ware fabricated, and also the specimen of sixty titanium plugs, the thirty gold alloy, thirty silver-palladium, and nickelc-hromium plugs were made. Thereafter, each plug of gold alloy, silver-palladium, and nickel-chromium inserted into the the titanium and acrylic resin plate, and also titanium plug inserted into the acrylic resin plate. The combination specimens uf galvanic couples immersed in 70m1 artificial saliva solution, and also specimens of four type alloy(that is, titanium, gold, silver-palladium and nickel-chromium alloy) plugs were immersed solely in 70m1 artificial sativa solution. The amount of metal elements released was observed during 21 weeks in the interval of each seven week. The electrochemical method was performed using computer-controlled potentiosta(Autostat 251. Sycopel Sicentific Ltd., U.K). The wax patterns(diameter 11.0mm, thickness,in 1.5mm) of four dental casting alloys were casted by centrifugal method and embedded in self-curing acrylic resin to be about $1.0cm^2$ of exposed surface area. Embedded specimens were polished with silicone carbide paper to #2,000, and ultrasonically cleaned. The working electrode is the specimen of four dental casting alloys, the reference electrode is a saturated calmel electrode(SCE) and the ounter electrode is made of platinum plate. In the artificial saliva solution, the potential scanning was carried out starting from-700mV(SCE) TO +1,000mV(SCE) and the scan rate was 75mV/min. Each polarization curve of alloy was recorded automatically on a logrithmic graphic paper by XY recorder. From the polarization curves of each galvanic couple, corrosion potential and corrosion rates, that is, corrosion density were compared and order of corrosion tendency was determined. From the experiments, the following results were obtained : 1. In the case of immersing titanium, gold alloy, silver-palladium alloy, and nickel-chromium alloysolely in the artificial saliva solution(group 1, 2, 3, and 4), the total amount of metal elements released was that group 4 was greater about 2, 3 times than group 3, and about 7.8 times than group 2. In the case of group 1, the amount of titanium released was not found after 8 week(p<0.001). 2. In the case of galvanic couples of titanium in contact with alloy(group 5, 6), the total amount of metal elements released of group 5 and 6 was less than that of group 7, 8, 9, and 10(p<0.05). 3. In the case of galvanic couples of titanium in contact with silver-palladium alloy(group 7, 8), the total amount of metal elements released of group 7 was greater about twice than that of group 5, and that of group 8 was about 14 times than that of group 6(p<0.05). 4. In the case of galvanic couples of titanium in contact with nickel-chromium alloy(group 9, 10), the total amount of metal elements released of group 9 and 10 was greater about 1.8-3.2 times than that of group 7 and 8, and was greater about 4.3~25 times than that of group 5 and 6(p<0.05). 5. In the effect of galvanic corrosion according to the difference of the area ratio of cathode and anode, the total amount of metal elements released was that group 5 was greater about 4 times than group 6, group 8 was greater about twice than group 7, and group 10 was greater about 1.5 times than group 9(p<0.05). 6. In the effect of galvanic corrosion according to the elasped time during 21 week in the interval of each 7 week, the amount of metal elements released was decreased markedly in the case of galvanic couples of the titanium in contact with gold alloy and silver-palladium alloy but the total amount of nickel and beryllium released was not decreased markedly in the case of galvanic couples of the titanium in contact with nickel-chromium alloy(p<0.05). 7. In the case of galvanic couples of titanium in contact with gold alloy, galvanic current was lower than any other galvanic couple. 8. In the case of galvanic couples of titanium in contact with nickel-chromium alloy, galvanic current was highest among other galvanic couples.

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.747-753
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• 2003

면역글로불린의 Fc 부분에 대한 수용기인 $Fc{\gamma}R$는 세균에 대한 인식, 결합과 포식작용과정에서 중요한 역할을 한다. 이 $Fc{\gamma}R$에서 $Fc{\gamma}R$IIa, $Fc{\gamma}R$IIIa, $Fc{\gamma}R$IIIb의 유전자 다형성이 치의학 분야에서 연구되고 있다. $Fc{\gamma}R$IIa에서는 두 번째 세포외 면역글로불린 유사 영역의 131번째 아미노산에서 아르기닌($Fc{\gamma}R$IIa-R131) 혹은 히스티딘($Fc{\gamma}R$IIa-H131)을 갖고 있으며, $Fc{\gamma}R$IIIa에서는 두번째 세포외 영역의 158번째 아미노산이 발린($Fc{\gamma}R$IIIa-158V) 혹은 페닐알라닌($Fc{\gamma}R$IIIa-158F)을 갖고 있다. $Fc{\gamma}R$IIIb에서는 첫 번째 세포외 면역글로불린 유사영역의 4개의 아미노산의 유전자 다형성으로 인해서 $Fc{\gamma}R$IIIb-NA1과 $Fc{\gamma}R$IIIb-NA2의 두가지 유전자 다형성을 보이고 있다. 이번 연구는 치주적으로 건강한 한국인에서 $Fc{\gamma}R$IIa, $Fc{\gamma}R$IIIa, $Fc{\gamma}R$IIIb에 대한 유전자형의 분포를 조사하고자 한 것으로 서울대학교 치과병원에 근무하는 치과의사, 치과위생사, 간호조무사 및 서울대학교 치과대학 4학년 학생 중 치주낭 깊이와 부착소실이 4mm 이하인 치주적으로 건강한 한국인 65명을 대상으로 하였다. $Fc{\gamma}R$IIa, $Fc{\gamma}R$IIIa, $Fc{\gamma}R$IIIb의 유전자 다형성은 분리한 DNA에 각 대립유전자에 특이성을 지닌 primer를 넣고 PCR(polymerase Chain Reaction)법을 이용하여 증폭시킨후 전기영동법을 이용하여 각 대립유전자의 존재를 확인함으로써 결정하였다. $Fc{\gamma}R$IIa의 유전자 다형성은 R/R131, R/H131, H/H131의 유전자형에 대하여 각각 7.7%, 38.5%, 53.8%의 분포를 보였으며, $Fc{\gamma}R$IIIa의 158V/V, 158V/F, 158F/F 유전자형에 대하여 각각 7.7%, 35.4%, 56.9%의 분포를 보였다. 또한 $Fc{\gamma}R$IIIb의 NA1/NA1, NA1/NA2, NA2/NA2 유전자형은 각각 33.9%, 53.8%, 12.3%의 분포를 보였다. 이를 바탕으로 각 대립유전자의 발생빈도 계산한 결과 $Fc{\gamma}R$IIa의 R131과 H131이 26.9% 73.1%로 나타났으며, $Fc{\gamma}R$IIIa의 158V, 158F의 유전자형이 25.4%, 74.6%로 나타났다. $Fc{\gamma}R$IIIb의 NA1, NA2 유전자형의 발생빈도는 60.8%, 29.2%로 나타났다. 이번 연구는 치주적으로 건강한 한국인에서의 $Fc{\gamma}R$IIa, $Fc{\gamma}R$IIIa, $Fc{\gamma}R$IIIb에 대한 유전자형의 분포를 조사한 것으로, 이후 치주질환자의 유전자형 분포와의 비교로 치주질환과 $Fc{\gamma}R$IIa, $Fc{\gamma}R$IIIa, $Fc{\gamma}R$IIIb의 유전자다형성과의 관련성에 관한 추가적인 연구가 필요할 것으로 여겨진다.

• Journal of The Korean Association For Science Education
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• v.31 no.8
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• pp.1092-1109
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• 2011

The purpose of this study was to analyze of the effects of instructional supervision emphasizing reflective thinking on science teaching of elementary teachers. The participants in this study were two teachers. This study was divided in former, middle, and later periods, and consisted of monitoring their own teaching, interviewing, journal writing, discussion with peer teachers and teacher training. Data included descriptions of nine science classes, nine interviews, seven journals and the journals of the researcher. Data analysis tools were the frameworks of the questions, feedback, teaching methods, elements of teaching behavior, and reflection levels. This study employed qualitative research, analysis of the frequency of data, and quoting of descriptions related to the result. The results of this study were as follows: First, teachers showed mainly technical reflection, but changed to show more practical reflection, and critical reflection in the later period of instructional supervision. Second, instructional supervision emphasizing reflective thinking on science teaching for elementary teachers meaningfully changed the question, feedback, teaching methods and teaching elements of teachers. From the results of this study, instructional supervision emphasizing reflective thinking on science teaching for elementary teachers can be considered an effective method in improving teaching elementary science, and instructional supervision used in this study made possible the higher level of reflection and appropriate teaching behavior.

• The Journal of Korean Academy of Sensory Integration
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• v.9 no.2
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• pp.1-13
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• 2011

Objective : Purpose of this study is to discuss benefits and implications of the clinical reasoning process and re-evaluation in the OTIPM by introducing a single case that occupational therapy intervention is provided based on the OTIPM. Methods : The case subject is a boy aged 5 years and 10 month who had diagnosed as attachment disorder and anxiety disorder from a pediatric psychiatrist before. The boy is referred to sensory integration therapy clinic and underwent occupational therapy intervention service twice a week for four month. Therapeutic activities for the intervention were consisted of sensory integration activities for restorative model, care-giver education for educational model, and performance skill training for acquisitional model. Measurements used in the initial evaluation are JSI-R, DDST-2, Social Maturity Test, KPPS-R, and observation-based performance task analysis. For the performance task analysis, performance skill items were constructed based on the Occupational Therapy Process Framework (OTPF), and those were assessed by the evaluation system of Assessment of Motor and Process Skill (AMPS) and Evaluation of Social Participation (ESI). Results : The detail process of implementing of the OTIPM in this study is reported by following four phases; 1) establish client-centered performance context; 2) establish baseline and interpret cause (initial evaluation); 3) intervention planning and implementing; and 4) recognize intervention outcome (reevaluation). Conclusion : In this case, occupational therapist could provide the client an occupation-based intervention within comprehensive performance context based on the OTIPM. Therapist could clearly identify the cause of problematic performance skills and behaviors and so provide effective intervention to improve client's occupational performance. Additionally, it was found that client's satisfaction of the intervention can be raised when the concept of 'who is the client' is expanded based on the OTIPM. From this study, it is proposed that OTIPM may be a model educible 'comprehensive' enhancement of 'specific' occupational engagement, as it considers both improvement of occupational performance and satisfaction.

• Journal of Aquaculture
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• v.1 no.1
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• pp.67-73
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• 1988

A growth experiment of tilapia (offsprings of the hybrid between Oreochromis niloticus and O. mossambicus) under different dissolved oxygen levels in the recirculating water system was conducted at the Fish Culture Experiment Station of the National Fisheries University of Pusan from February 4 to March 5, 1986. Six tanks with a capacity of $1.8m^3$ of water each were used under the same condition of water parameters except for dissolved oxygen levels which were designated to maintain at 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0 mg/$\iota$. Each tank was stocked with 90 kg of fish each averaging 64 to 69 grams. The average water temperature during the course of the experiment was $22.5^{\circ}C$. The results obtained are summarized as follows: The food conversion efficiencies were very good, being 1.05-1.11 at 3.5, 3.0, 2.5 and 2.0 mg/$\iota$ DO levels without any significant differences among them, but at 4.0 mg/$\iota$ the F. C. was 1.39 and at 1.5 mg/$\iota$ it was 1.61 being very poor compared with the others. The daily growth rate performance was best at 3.5 mg/$\iota$ dissolved oxygen level followed by 3.0 and 2.5 mg/$\iota$ with slight differences while at 4.0 and 2.0 mg/$\iota$ DO levels the growths were significantly poor, and at 1.5 mg/$\iota$ DO level it was extremely poor. In 1.5 mg/$\iota$ group, the fish did not accept feed vigorously and after feeding the fish usually concentrated around the inflow point showing oxygen deficiency response. While at 4.0 mg/$\iota$ high feeding rates tended to waste significant amounts of feed while eating and led to water deterioration, and above these levels the results is considered to lead to a waste of energy with uneconomical performance. On the other hand, at and below 2.0 mg/$\iota$ DO level the tilapia certainly showed a poor growth performance. The experiment indicates that the DO range of 2.5$\~$3.5 mg/$\iota$ is the optimum level for the good growth performance.

• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.197-204
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• 2000

[$K^+$]-selective ion channels were studied in excised inside-out membrane patches from human osteoblast-like cells (G292). Three classes of $K^+$channels were present and could be distinguished on the basis of conductance. Conductances were $270\pm27\;pS,\;113\pm12\;pS,\;48\pm8\;pS$ according to their approximate conductances in symmetrical 140 mM KCl saline at holding potential of -80 mV It was found that the small conductance (48 pS) $K^+$channel activation was dependent on membrane voltage. In current-voltage relationship, small conductance $K^+$channel showed outward rectification, and it was activated by the positive potential inside the membrane. In recordings, single channel currents were activayed by a negative pressure outside the membrane. The membrane pressure increased $P_{open}$ of the $K^+$ channel in a pressure-dependent manner. In the excised-patch clamp recordings, G292 osteoblast-like cells have been shown to contain three types of $K^+$ channels. Only the small conductance (48 pS) $K^+$channel is sensitive to the membrane stretch. These findings suggest that a hyperpolarizing current, mediated in part by this channel, may be associated with early events during the mechanical loading of the osteoblast. In G292 osteoblast-like cells, $K^+$channel is sensitive to membrane tension, and may represent a unique adaptation of the bone cell membrane to mechanical stress.

• The korean journal of orthodontics
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• v.36 no.5
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• pp.349-359
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• 2006

Objective: Nickel-titanium alloy wire possesses excellent spring-back properties, shape memory and super-elasticity. In order to adapt this wire to clinical use, it is necessary to bend as well as to control its super-elastic force. The purpose of this study is to evaluate the effects of heat treatment on the load-deflection properties and transitional temperature range (TTR) of nickel-titanium wires. Methods: Nickel-titanium wires of different diameters ($0.016"\;{\times}\;0.022"$, $0.018"\;{\times}\;0.025"$ and $0.0215"\;{\times}\;0.028"$) were used. The samples were divided into 4 groups as follows: group 4, posterior segment of archwire (24 mm) without heat treatment; group 2, posterior segment of archwire (24 mm) with heat treatment only; group 3, anterior segment with bending and heat treatment; group 4, anterior segment with bending and 1 sec over heat treatment. Three point bending test was used to evaluate the change in load-deflection curve and obtained DSC (different scanning calorimetry) to check changes in $A_f$ temperature. Results: In the three point bending test, nickel-titanium wires with heat treatment only had higher load-deflection curve and loading and unloading plateau than nickel-titanium wires without heat treatment. Nickel-titanium wires with heat treatment had lower Af temperature than nickel-titanium wires without heat treatment. Nickel-titanium wires with heat treatment and bending had higher load-deflection curve than nickel- titanium wires with heat treatment and nickel-titanium wires without heat treatment. Nickel-titanium with heat treatment of over 1 sec and bending had the highest load-deflection curve. Nickel-titanium wires with heat treatment and bending had lower Af temperature, Nickel-titanium wires with heat treatment of over Af sec and bending had the lowest Af temperature. Conclusion: From the results of this study, it can be stated that heat treatment for bending of Nickel-titanium wires does not deprive the superelastic property but can cause increased force magnitude due to a higher load-deflection curve.

• KSBB Journal
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• v.11 no.3
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• pp.295-302
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• 1996

The measurements of rubisco parameters are important in photosynthetic studies. In this experiment, we used photometric assay method to detect these major parameters, such as activity, carbamylation and amount of rubisco. The main advantages of this method are very simple and as sensitive as conventional methods which usually produce radioactive waste. In this study, with kidney bean (Phaseolus vulgatis L.) leaves grown at normal $CO_2$ (350ppm) and high $CO_2$ (650 ppm), we investigated the effect of $CO_2$ concentration on activation and carbamylation of rubisco by measuring the rubisco activity, carbamylation rate and amount of rubisco using a dual beam (334nm and 405nm) spectrophotometer, and analyzed the polypeptide profiles of rubisco by SDS-PAGE. When $CO_2$ concentration was raised from 350ppm to 650ppm, all parameters of rubisco were decreased : $41.2{\mu}M/m^2/s and 52.2{\mu}M/m^2/s$ to $27.4{\mu}M/m^2/s and 46.1{\mu}M/m^2/s$ for initial and total rubisco activity, respectively ; from 79% to 58.9% for carbamylation rate ; from $1.94 {\mu}M/m^2$ to 1.58{\mu}M/m^2$ for amount of rubisco. These results suggests that the decrease in rubisco activity at high $CO_2$ was caused by carbamylation. The analysis of the preparation by SDS-PAGE showed two major polypeptides at 50 and 14.5 kD which were identified as the large and the small subunits of rubisco. There were no differences in the intensity compared high $CO_2$ to normal $CO_2$ in both 50 kD and 14.5 kD bands. We also found that these inhibitory effects of $CO_2$ were reversible. When high $CO_2$ was switched to normal $CO_2$, the parameters of rubisco changed were almost the same as normal rubisco parameters. These data provide an evidence that activity of rubisco was recovered by $CO_2$ concentration of 350 ppm.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.1
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• pp.46-50
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• 1983

In order to find out the possibility of utilizing red pepper seed as food resources of fats and proteins, a series of studies were conducted. The red pepper seed contained 27.6% of crude fat and 22.2% of crude protein. The lipid fractions obtained by silicic acid column chromatography were mainly composed of 95.4% neutral lipid, where as compound lipid were 4.6%. Among the neutral lipid separated by thin layer chromatography, triglyceride was 85.6%, sterol ester 4.9%, free fatty acids 3.4%, diglyceride 2.5%, sterol 2.2% and monoglyceride 1.1%, respectively. The predominant fatty acids of red pepper seed oil were linoleic acid (57.1-75.4%), palmitic acid (13.9-21.3%) and oleic acid (8.0-15.1%), especially glycolipid contained 1.7% of linolenic acid and small amount of myristic acid and arachidic acid. The salt soluble protein of red pepper seed was highly dispersible in 0.02M sodium phosphate buffer containing 1.0M $MgSO_4$, and the extractability of seed protein was about 25.0%. Glutamic acid and arginine were major amino acids of red pepper seed protein. The electrophoretic analysis showed 6 bands in seed protein, and the collection rate of the main protein fraction purified by sephadex G-100 and G-200 was about 62.2%. Glutamic acid (19.9%) was major amino acid of the main protein, followed by glycine and alanine. The molecular weight of the main protein was estimated to be 93,000.

• Development and Reproduction
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• v.11 no.2
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• pp.127-135
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• 2007

In order to monitor the developmental features of embryos, larvae, and juveniles of Konoshiro Gizzard Shad Konosirus punctatus, the fertilized eggs were gotton using artificial insemination. Konosirus punctatus were caught in Mankyung-myeon, Kimjae, Jeollabuk-do at June of 2004, and experiments were carried out in Ichthyology laboratory in Chonnam National University. Konosirus punctatus spawned draft egg from March to June. The fertilized eggs were cultured in $19.0{\sim}23.0^{\circ}C$(mean, $21.2^{\circ}C)$. The eggs had spherical shape and the diameter is $1.14{\sim}1.34\;mm$(mean, 1.21 mm). The lens began to appear from 35 hr 53 min after fertilization. At the moment, the movement of larvae was more active, and the tail was separated completely from yolk, the heart had forms, and melanophore appeared. Hatching was observed from 37 hr 10 min after fertilization. The total length of the hatched larvae was $4.26{\sim}5.30\;mm$(mean, 4.96 mm), but the mouth and anus were not opened at the time when the larva had yolk sack, and had $22{\sim}27$ myometium, and the anus located just abdominal front of the tail fin, and melanophore accumulated in the eye. Post-larvae used yolk completely after 2 day of hatching, and the total length was $4.96{\sim}5.74\;mm$(mean, 5.24 mm). From 16 days after hatching, the tail had curved tail end, and appeared the stems for pectoral, dorsal, and caudal fins. At 53 days after hatching, the total length of post-larvae was $27.11{\sim}34.09\;mm$(mean, 30.11 mm), and the frontal part of head developed like an adult one. At this time, fins and body are transferred to those of adult Konosirus punctatus. Fishes have a different shape and location of melanophore even in the same family. This research was tried to elucidate the early developmental features of Konosirus punctatus, together with species-specific pattern of melanophore.