• 식물조직배양학회지
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• 제22권6호
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• pp.329-334
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• 1995

효과적인 형질전환 시스템을 이용하여 왜화유전자인 rolC 유전자를 구기자나무로의 형질전환 시스템을 확립하였다. 침으로 자극된 엽절편을 2.0 mg/L zeatin이 함유된 3/2 MS배지에 배양하였을 때 엽표면으로부터 줄기재분화가 되었다. 그러나 여러 농도의 kanamycin sulfate와 2.0 mg/L Aeatin이 함유된 배지에 엽절편을 배양하였을 때는 kanamycin sulfate의 농도가 증가할수록 줄기 유발수가 감소하는 것을 볼 수 있었으며, 적정선발농도는 10 mg/L이었다. 엽절편은 공동배양 시간에 따라서 생존율과 줄기재분화에 매우 큰 영향을 미쳤다. 엽절편의 생존율은 dipping할 경우가 가장 좋았으며, 배양시간이 길수록 엽절편의 백색화가 관찰되었고, 생존율이 급격히 감소하는 것을 볼 수 있었다. 줄기재분확에 가장 적합한 공동배양 시간은 24시간으로 나타났다. 공시균주와 24시간 동안 공동배양한 엽절편을 10mg/L의 kanamycin sulfate와 2.0 mg/L zeatin이 함유된 줄기 유도배지에 배양한 결과, 105개의 엽절편 중 80개의 엽절편이 생존하였으며, 그 중에서 15개의 재분화된 줄기를 얻었다. 재분화된 줄기들은 형질전환여부를 판명하기 위해 1차적으로 10 mg/L kanamycin sulfate가 함유된 배지에 옮겨 4 주간 배양한 결과, 항생제에 대해서 저항성을 가진 5개의 식물체를 선발할 수 있었다. 2차적으로 rolC유전자와 NPTII 유전자 도입의 유무를 검증하기 위하여 Southern 분석을 행한 결과, 구기자의 형질전환 식물체에서 rolC 유전자 probe의 coding sequence와 동일한 것으로 생각되는 1kb위치와 NPTII probe의 coding sequence와 동일한 것으로 생각되는 2.6kb 위치에서 각각의 밴드를 확인할 수 있었다.

• Journal of Yeungnam Medical Science
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• 제7권1호
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• pp.69-80
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• 1990

본 영남의대 정형외과학 교실에서는 1984년 1월 부터 1988년 5월 까지 입원 치료한 대퇴 경부 골절 환자 중 최근까지 2년 이상 추적 조사가 가능 하였던 23명의 24례를 대상으로 하여 고찰한 결과를 요약하면 다음과 같다. 1. 총 23명중 여자가 19명, 65세 이상의 노년층의 환자가 11명으로 노년층의 여자에서 호발하였다. 2. 18례에서 경도의 외력에 의한 것이었고 65세 이상의 12례 중 전례에서 경도의 외력에 의해 골절되었고 8례에서 심각한 골조송증을 보였다. 3. 24례 중 14례에서 전위된 골두하 골절이었고 6례에서 전위된 횡경부 골절이었으며 4례에서 전위되지 않은 횡경부 골절이었다. 4. 치료는 14례에서 도수 정복후 내고정을 10례에서 일차적 관절 치환술을 시행하였고 내고정한 14례중 4례에서 대퇴 골두 괴사로 이차적 관절 치환술을 시행하였다. 5. 내고정을 시행한 14례 중 7례에서 합병증을 관찰할 수 있었고 무혈성 괴사가 6례, 불유합 2례, Pin 이동 3례, 내고정물 부전이 1례였다. 6. 관절 치환술을 시행한 14례에서 수술 직후의 대퇴경의 수술적 접합률이 대퇴경의 해리와 관계가 있었다.(r=-0.68. p<0.01) 대퇴 경부 골절의 치료시에 합병증의 발생은 대개 골절의 양상 및 치료시기, 정복의 정도에 의해 결정되며 치료의 지연, 정복의 불가능, 과내반 교정, 병적 골절일 경우에는 일차적 고관절 치환술이 환자의 조기 거동과 사망률의 감소를 위해 바람직할 것으로 사료된다.

• Tribology and Lubricants
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• 제25권5호
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• pp.318-323
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• 2009

The oil characteristics and wear particles of Diesel engines with a DPF have been investigated as a function of a driving distance. The engine oil of SAE 5W30 with ACEA C3 is used for an oil film lubrication of the engine, which is equipped with Diesel particulate filter. Depending on the oil test results, the kinematic viscosity of used engine oils at 40 is degraded up to 5.1% compared with that of unused engine oils, SAE 5W30. And the kinematic viscosity of used engine oils at 100 is more degraded up to 8.1% compared with that of unused engine oils. The oil characteristic as a function of a mileage is not changed depending on the driving distance because of high quality of engine oils. But the aluminum and copper compounds, which are used as base materials of the engine bearing and a pin bush, are much worn and contaminated for the increased mileage of the car. The oil properties of used engine oils are relatively good except phosphorus and calcium additives, which are heavily engaged in the performance of the oils.

• Clinics in Shoulder and Elbow
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• 제2권2호
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• pp.133-137
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• 1999

Purpose: There are so many different methods with the their own advantages and disadvantages for acute AC dislocation and distal unstable clavicle fracture. We evaluated the usefulness of temporary Bosworth's coracoclavicular fixations using the cannulated screw and reviewed our clinical results. Materials and Methods: We evaluated 34 cases of temporary coracoclavicular fixations with cannulated screw and washer for acute AC dislocation(25cases in the Type V, Ⅲ) and distal unstable clavicle fracture(9cases in the Type ⅡB, Ⅱ+Ⅲ). All cases were fixed by the same techniques, guided cannulated screw under C-arm after the repair of the CC ligament within 1 week. Bases on the regular check, screws were removed at the 6-12 weeks under local anesthesia. The final clinical and radiological results(average 14 months follow-up) were rated with the UCLA scale. Results : All shoulders were gained nearly full ROM passively at the 3-4 weeks. The overall satisfactory resuIts(excellent or good) were achieved 88%(22/25) in the acute AC dislocation and all in the distal unstable clavicle fracture. There were no definite complications except three initial fixations loosening. Conclusion: Temporary Bosworth's coracoclavicular fixation using the cannulated screw with guided pin was simple precedure and provided enough initial stability for acute AC dislocation and distal unstable clavicle fracture.

• 한국전자파학회논문지
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• 제16권4호
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• pp.359-365
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• 2005

본 논문에서는 소형, 경량이면서 PCS/IMT-2000 및 Wibro 대역을 포함할 수 있는 새로운 내장형 안테나를 설계하였다. 안테나의 크기를 줄이기 위해 단락핀을 사용하였으며, 광대역 특성을 얻기 위해 슬릿을 부가하였다. 안테나의 설계는 유한 적분법과 구조 근사법을 기본 이론으로 하는 CST Microwave Studio 상용 프로그램을 사용하여 최적화한 후, 제작하고 측정하였다. 측정 결과, 중심주파수 $1.934\;\cal{GHz}$에서 안테나의 대역폭(VSWR<2.5)이 $40.8\;\%$로 광대역 특성을 얻었으며, 제작된 안테나의 전체 크기는 $30\;\cal{mm}\times10\;\cal{mm}\times0.2\;\cal{mm}$이다.

• 한국임상수의학회지
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• 제36권1호
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• pp.82-84
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• 2019

A common kestrel (Falco tinnunculus) was presented with inability to stand and fly at Chungnam Wild Animal Rescue Center. The kestrel showed non-weight bearing ambulation on both legs and crepitation with no external wound. Radiographs revealed a fracture on mid-diaphysis of right tibiotarsus and a distal end fracture of left femur. Intramedullary pinning was chosen for reduction of both fractures. The right tibiotarsal fracture was corrected first, and left femur was repaired 5 days later. The kestrel was managed with a specially designed sling to prevent further iatrogenic damage for 2 weeks. Three weeks after the surgery, the kestrel was able to stand and found to perch in 4 weeks. On 5 weeks, The kestrel could fly free at outdoor aviary and was released through rehabilitation for 3 months finally.

• 대한금속재료학회지
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• 제46권11호
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• pp.725-729
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• 2008

Deposition characteristics of electroless plated Ni-W-P films were investigated for various complexing agents. Used complexing agents are sodium citrate, sodium gluconate and sodium malonate. In this study, the existing mixed potential theory could explain the overall mechanism of Ni-W-P electroless plating for all complexing agents. The deposition rate could be also expected by the theory. The deposited Ni-W-P films were evaluated in term of surface hardness and corrosion resistance. Microhardness of the deposit increased about 1,000 Hv after heat treatment for one hour at $400^{\circ}C$, because it was above the crystallization temperature of $Ni_3P$. The deposited Ni-W-P films can exhibit excellent corrosion resistance in using sodium malonate as a complexing agent, the other hand the using sodium gluconate was the worst corrosion resistance. The worst corrosion resistance was due to a large number of nano-sized pin-holes or small pores. The plating current at the mixed potential increases when the using sodium malonate as a complexing agent, it was explained by the cross section.

• Nuclear Engineering and Technology
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• 제54권3호
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• pp.803-810
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• 2022

The small modular liquid-metal fast reactor (SMFR) is an important component of advanced nuclear systems. SMFRs exhibit relatively low breeding capability and constraint space for control rod installation. Consequently, control rods are deeply inserted at beginning and are withdrawn gradually to compensate for large burnup reactivity loss in a long lifetime. This paper is committed to investigating the impact of control rod compensation operation on core neutronics characteristics. This paper presents a whole core fine depletion model of long lifetime SMFR using OpenMC and the influence of depletion chains is verified. Three control rod position schemes to simulate the compensation process are compared. The results show that the fine simulation of the control rod compensation process impacts significantly the fuel burnup distribution and absorber consumption. A control rod equivalent position scheme proposed in this work is an optimal option in the trade-off between computation time and accuracy. The control position is crucial for accurate power distribution and void feedback coefficients in SMFRs. The results in this paper also show that the pin level power distribution is important due to the heterogeneous distribution in SMFRs. The fuel burnup distribution at the end of core life impacts the worth of control rods.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.347-351
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• 2004

[ $Si_3N_4$ ] composites have been extensively studied for engineering ceramics, because it has excellent room and high temperature strength, wear resistance properties, good resistance to oxidation, and good thermal and chemical stability. In the present work, carbon short fiber reinforced $Si_3N_4$ ceramics were fabricated by hot press method in $N_2$ atmosphere at $1800^{\circ}C$ using $Al_2O_3\;and\;Y_2O_3$ as sintering additives. Content of carbon short fiber was $0\%,\;0.1\%\;and\;0.3\%$. The composites were evaluated in terms of density, flexural strength and elastic modulus through the 3-point bending test at room temperature. Also, The wear behavior was determined by the pin on disk wear tester using silicon nitride ball. Experimental density and flexural strength decreased with increasing content of carbon fiber. But specific modulus increased with increasing content of carbon fiber. In addition, friction coefficient and specific wear loss decreased with increasing content of carbon short fiber by reason of interfacial defects between matrix and fiber.

• 대한물리치료과학회지
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• 제4권2호
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• pp.399-403
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• 1997

The purpose of this study was to determine the efficacy of electrode placement on procaine iontophoresis. Thirty-three healthy students with an age range of 19 to 34 years, were participated in this study. The subjects were randomly assigned into 3 groups. Each subjects received iontophoresis on the proximal 1/3 of volar surface of dominant forearm with soft cotton pad($3.5{\times}3.5cm$) soaked in 2 ml of 4% procaine hydrochloride (pH 5.1) at 4 mA for 10 minutes(total current 40 mA min) of anodal DC. In transversal electrode placement(TEP) group, dispersive electrode was placed on the proximal 1/3 of dorsal surface of the forearm. In longitudinal electrode placement (LEP) group and control group, dispersive electrode were placed on the distal 1/3 of volar surface of the forearm. After procaine iontophoresis, duration of anesthesia were evaluated at five minutes intervals on five random locations in the iontophoretically area using a 21-gauge sterile hypodermic needle pressed with 1 mm invagination until return the sharp pin-pricking pain sensation. The data were ana lysed with one-way ANOVA to determine signific~nt differences between groups. The results showed significantly differences in the local anesthetic duration between the 3 groups(p<0.001). The anesthetic durations of TEP group and LEP group were significantly longer when compared with control group(p<0.05). Anesthetic durations of TEP group and LEP group were not significantly difference, but anesthetic duration of LEP group tends to longer than TEP group. In view of these results, clinicians should consider the electrode placement method when performing the iontophoresis.