• Analytical Science and Technology
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• v.15 no.3
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• pp.229-235
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• 2002

Plasma source ion implantation (PSII) technique was utilized to improve the wettability of polystyrene surfaces. It is well known that treated surfaces undergo aging, leading to hydrophobic recovery with time. We investigated the aging effect of polystyrene thin film on the various molecular weights. Polystyrenes with several molecular weights ($M_w$ = 760, 2430, 31600, 115700, 280000, 903600) were treated in different experimental conditions including gas species and pulse energy, and their hydrophilicity was measured by contact angle goniometer. To study wettability decay as a function of the molecular weight, PSII-treated samples were aged at different temperatures. Hydrophobic recovery of high molecular weight polystyrene was much slower than that of low molecular weight, even at high temperatures. The methods used to characterize treated surfaces were water contact angle measurement, TOF-SIMS, XPS, SEM and AFM.

• Journal of Microbiology and Biotechnology
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• v.26 no.11
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• pp.1908-1917
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• 2016

Wild strain L-6 was subjected to combined mutagenesis, including UV irradiation, atmospheric and room temperature plasma, and ion beam implantation, to increase the yield of 1,3-dihydroxyacetone (DHA). With application of a high-throughput screening method, mutant Gluconobacter oxydans I-2-239 with a DHA productivity of 103.5 g/l in flask-shake fermentation was finally obtained with the starting glycerol concentration of 120 g/l, which was 115.7% higher than the wild strain. The cultivation time also decreased from 54 h to 36 h. Compared with the wild strain, a dramatic increase in enzyme activity was observed for the mutant strain, although the increase in biomass was limited. DNA and amino acid sequence alignment revealed 11 nucleotide substitutions and 10 amino acid substitutions between the sldAB of strains L-6 and I-2-239. Simulation of the 3-D structure and prediction of active site residues and PQQ binding site residues suggested that these mutations were mainly related to PQQ binding, which was speculated to be favorable for the catalyzing capacity of glycerol dehydrogenase. RT-qPCR assay indicated that the transcription levels of sldA and sldB in the mutant strain were respectively 4.8-fold and 5.4-fold higher than that in the wild strain, suggesting another possible reason for the increased DHA productivity of the mutant strain.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.184-184
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• 1999

반도체소자의 고집적, 미세화에 따라 MOSFET 소자에서의 고농도, 미세접합이 요구되고 있다. 이러한 고농도, 미세접합을 형성하기 위하여 기존의 저에너지 이온주입법을 대체 또는 병행할 목적으로 플라즈마 이온주입방법이 활발히 연구되고 있다. 본 연구에서는 플라즈마 이온주입방법을 이용하여 (100) 실리콘 기판에 보론을 주입후 열처리하여 형성된 p+층의 도펀트의 활성화와 이온주입으로 인한 실리콘 기판의 손상을 고찰하였다. 본 실험에서 (100)실리콘 기판에 도핑할 소스 가스로 BF3을 주입하고, D.C. pulse 플라즈마 도핑시스템을 사용하여 플라즈마 내의 보론이온을 웨이퍼 홀더에 -1~-5kV의 인가된 음전압에 의해 가속시키어 실리콘 웨이퍼에 주입하였다. 주입에너지 -1kV, -3kV, -5kV와 1$\times$1015, 3$\times$1515의 dose로 주입된 실리콘 기판을 급속가열방식(RTP)을 사용하여 $600^{\circ}C$~110$0^{\circ}C$의 온도구간에서 10초와 30초로 열처리하여 도펀트의 활성화와 미세접합을 형성한 후 SIMS, four-point probe, Hall 측정, 그리고 FT-IR을 이용하여 플라즈마 이온주입된 도펀트의 거동과 활성화율을 관찰하였고 FT-IR과 TEM의 분석을 통하여 이온주입으로 인한 실리콘 기판의 손상을 고찰하였다. SIMS, four-point probe, Hall 측정, 그리고 FT-IR의 분석으로 열처리 온도의 증가에 따라 도펀트의 활성화율이 증가하였고, 이온주입 에너지와 dose 그리고 열처리 시간의 증가에 따라서 주입된 도펀트의 활성화는 증가하였다. 그리고 주입에너지와 dose 그리고 열처리 시간의 증가에 따라서 주입된 도펀트의 활성화는 증가하였다. 그리고 주입에너지와 dose를 증가시키면 접합깊이가 증가함을 관찰하였다. 이온주입으로 인한 기판손상의 분석을 광학적 방법인 FT-IR과 미세구조를 분석할 수 있는 TEM을 이용하여 분석하였다. 이온주입으로 인한 dislocation이나 EOR(End Of Range)과 같은 extended defect가 없었고, 이온주입으로 인한 비정질층도 없는 p+층을 얻을수 있었다.

• The Journal of Korean Academy of Prosthodontics
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• v.30 no.3
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• pp.361-378
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• 1992

The purpose of this investigation was to evaluate the effect of the porous hydroxyapatite particles (Interpore $200^{(R)}$) and guided tissue regeneration membrane ($Gore-Tex^{TM}$ augmentation material) on amount and shape of generating new bone adjacent to implant. Implants were placed immediately after extraction in the bilateral 3rd, 4th premolars of the mandible of the adult dogs. In all experimental groups, artificial bony defects were formed at the buccal cortex area, 3.3mm in width and 3.0mm in depth. In the control group : sutured without HA particles & membranes after placing implants, the experimental group 1 : membrane was place over the artificial bony defect, the experimental group 2 : bony defect was filled with HA particles and covered with membrane. The examination of bone-implant interfaces using light microscope and fluorescent microscope concluded as follows. 1. In all three experimental groups, osseointegration was observed without epithelial migration. 2. In the healing degree of bony defect area, the experimental group 1, 2 showed more prominent healing than control group, and the experimental group 1 showed the most excellent bone formation. 3. In fluorescent microscopic finding, bone remodeling was observed in regenerated bone tissue at defect area of experimental group 1, but in experimental group 2, irregular, discontinuous linear fluorescence was observed at the lower portion of defect area and sign of bone remodeling was weak.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.256-261
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• 2018

Recently, the number of cardiovascular disease-related deaths worldwide has increased. Therefore, the importance of percutaneous cardiovascular intervention and drug-eluting stents (DES) has been highlighted. Despite the great clinical success of DES, the re-endothelialization at the site of stent implantation is retarded owing to the anti-proliferative effect from the coated drug, resulting in late thrombosis or very late restenosis. In order to solve this problem, studies have been actively carried out to excavate new drugs that promote rapid re-endothelialization. In this study, we introduced hydrophilic drug, tauroursodeoxycholate (TUDCA), that improves the proliferation of endothelial progenitor cells and promotes apoptosis of vascular smooth muscle cells. In addition, we utilized shellac, which is a natural resin from lac bug to coat TUDCA on the surface of the metal. When using conventional coating method including biodegradable polymers and organic solvents, phase separation between polymer and drug occurred in the coating layer that caused incomplete incorporation of drug into the polymer layer. However, when using shellac as a coating polymer, no phase separation was observed and drug was fully covered with the polymer matrix. In addition, by adjusting the composition of coating solution and modifying the hydrophilicity of the metal surface using oxygen plasma, the surface roughness decreased due to the increased affinity between coating solution and metal surface. This result provides a method of depositing a hydrophilic drug layer on the stent.

• Journal of the Korean Magnetics Society
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• v.8 no.6
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• pp.346-349
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• 1998

In order to reduce to the defect density in poly-Si/SiO$_2$ thin films, where poly-Si is either undoped or doped by BF$_2$ implantation, the poly-Si/SiO$_2$ samples have been hydrogenated by rf plasmas of low temperature. Before hydrogenation, both $P_b$ centers and E centers were observed in the poly-Si(undoped)/SiO$_2$ and in the poly-Si(doped)/SiO$_2$. After 30 min hydrogenation, the $P_b$ center was reduced by 80 % doped sample and by 76 % in the undoped sample and the E center was not observed. After 90min hydrogenation, however, increases of the $P_b$ centers and regenerations of the E center were observed in the undoped sample as well as in the doped one. Compared with the undoped sample, the increase of $P_b$ center in the doped one was more dominant.

• Journal of Chest Surgery
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• v.13 no.3
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• pp.174-185
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• 1980

It was my great nohour that I can be exposed to such plenty materials of the coronary bypass surgery. Here, I am summarizing the xoronary bypass surgery, clinically. The material is serial 101 patients who underwent coronary bypass surgery between July 17, 1979 to November 30, 1979 in Shadyside Hospital, University of Pittsburgh. 1. Incidence of the Atherosclerosis is frequent in white, male, fiftieth who are living in industrialized country. It has been told the etiologic factor of the atherosclerosis is hereditary, hyperlipidemia, hypertension, smoking, drinking, diabetes, obesity, stress, etc. 2. The main and most frequent complication of the coronary atherosclerosis is angina pectoris. Angina pectoris is the chief cause of coronary bypass surgery and the other causes of coronary bypass surgery are obstruction of the left main coronary artery, unstable angina, papillary muscle disruption or malfunction and ventricular aneurysm complicated by coronary artery disease. 3. The preoperative clinical laboratory examination shows abnormal elevation of plasma lipid in 82 patint, plasma glucose in 40 patient, total CPK-MB in 24 patient stotal LDH in 22 patient out of 101 patient. 4. Abnormal ECG findings in preoperative examine were 29.1% myocardial infarction, 25.8% ischemia and injury, 14.6T conduction defect. 5. Also we had done Echocardiography, Tread Mill Test, Myocardial Scanning, Vectorcardiography and Lung function test to get adjunctive benefit in prediction of prognosis and accurate diagnosis. 6. The frequency of coronary atherosclerosis in main coronary arteries were LAD, RCA and Circumflex in that order. 7. The patients' main complaints which were became as etiologic factor undergoing coronary bypass surgery were angina, dyspnea, diaphoresis, dizziness, nausea and etc. 8. For the coronary bypass surgery, we used cardiopulmonary bypass machine, non-blood, diluting prime, cold cardioplegic solution and moderate cooling for the myocardial protection. 9. We got the grafted veins from Saphenous and Cephalic vein. Reversed and anastomosed between aorta and distal coronary A. using 5-0 and 7-0 prolene continuous suture. Occasionally we used internal mammary A. as an arterial blood source and anastomosed to the distal coronary A. and to side fashion. 10. The average cardiopulmonary bypass time for every graft was 43.9 min. and aortic clamp time was 23 minute. We could Rt. coronary A. bypass surgery only by stand by the cardiopulmonary machine and in the state of pumping heart. 11. Rates by the noumbers of graft were as follow : 21.8% single, 33.7% double, 26.7% triple, 13.9% quadruple, 3% quintuple and 1% was sixtuple graft. 12. combined procedures with coronary bypass surgery were 6% aneurysmectomy, 3% AVR, 1% MVR, 13% pacer implantation and 1% intraaortic ballon setting. 13. We could see the complete abolition of anginal pain after operation in 68% of patient, improvement 25.8%, no change in 3.1%, and there was unknown in 3%. 14. There were 4% immediate postoperative deaths, 13.5% some kinds of heart complication, 51.3% lung complications 33.3% pleural complications as prognosis.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.10
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• pp.1496-1502
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• 2007

The roles of melatonin in the control of deiodinase (MD) activity in cashmere goat skin and associated cashmere fibre growth were investigated. Eighteen half-sib Chinese Inner Mongolia cashmere wethers were allocated randomly to two groups (n = 9/group). One group was implanted subcutaneously with melatonin (2 mg/kg BW) at three 2-monthly intervals while the other group served as a control. All goats were maintained under natural photoperiodic conditions and were grazed on natural pasture. The plasma melatonin concentration showed a significant difference (p<0.01) between the implant group (M) and the control group (C) but plasma $T_4$ (or $T_3$) showed no significant difference (p>0.05). The monodeiodinase type II (MDII) activity in skin tended to increase gradually from the summer solstice to November. During July and August, the activity of MDII for the M group was higher (p<0.05) than that of the C group; also during this period, there was a significant positive correlation between MDII activity of skin and cashmere fibre growth rate. The monodeiodinase type III (MDIII) activity and the ratio of MDIII and MDII tended to decrease from the summer solstice to November. The ratio of MDIII and MDII for the M group was lower (p<0.05) than that of the C group in July and August. The cashmere fibre growth rate of the M group was significantly greater than that of the C group in July (p<0.01), August (p<0.001) and September (p<0.05). The cashmere fibre diameter and guard hair and body weight were not influenced (p>0.05) by melatonin implantation. The results demonstrate that melatonin plays an important role in the regulation of skin MD activity. Simultaneously, the cashmere fibre elongation stimulated by melatonin may result from enhanced MDII activity during a period of two months after melatonin treatment.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.225-243
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• 1991

In recent years immediate implantation has been tried by a few clinicians. This study placed IMZ implants in the rabbit femur with and without bony defects around the implant for simulating fresh extraction site. And one group with bony defects used porous hydroxyapatite ganules(HA) to fill if and the other group left the bony defects around the implant. The purpose of this study was to compare the shear bond strength and the bony contact and formation around the implant. Fifteen rabbits were divided into three groups and placed 10 IMZ implants to each group. Implant sites were surgically prepared with IMZ drills kit and implants were placed(Control), artificial bony defect was created with Apaceram drills kit around the implant sites and implants were placed(Experimental I), bony defect was filled with porous hydroxyapatite granules(Experimental II). Thereafter, rabbits were sacrificed at 8th week and specimens were prepared and pushout tested for shear bond strength of bone-implant interface immediately. Undecalcified and decalcified specimens were prepared with Vilanueva and hematoxylin-eosin stain for light microscopic finding. The results of this study were as follows. 1. In the control group, mean shear strength of bone-implant interface was $2.614{\pm}0.680$ MPa, experimental I was $0.664{\pm}0.322$ MPa, and experimental II was $2.281{\pm}0.606$ MPa. There was significant difference between control and experimental I, between experimental I and experimental II, but did not show significant difference between control and experimental II statistically. 2. In the bony formation surrounding IMZ implant of the three groups, that of cortical bone is more advanced than cancellous bone area. 3. In the histological findings of undecalcified specimens, control and experimental II showed more than 50% of bony or osteoid formation at the bony-implant interface. 4. In the histological findings of undecalcified specimens, experimental I showed less than 50% of bony or osteoid formation at the interface, and observed partial bony defect in the coronal zone. 5. In the experimental II group, were observed direct bony contact to hydroxyapatite granules, and infiltration of a few giant cells. 6. No inflammatory responses were seen around the titanium implants and the hydroxyapatite granules.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1540-1545
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• 2012

Steroidogenesis requires coordination of the anabolic and catabolic pathways of lipid metabolism, but the profile of proteins associated with progesterone synthesis in cyclic and pregnant corpus luteum (CL) is not well-known in cattle. In Experiment 1, plasma progesterone level was monitored in cyclic cows (n = 5) and pregnant cows (n = 6; until d-90). A significant decline in the plasma progesterone level occurred at d-19 of cyclic cows. Progesterone level in abbatoir-derived luteal tissues was also determined at d 1 to 5, 6 to 13 and 14 to 20 of cyclic cows, and d-60 and -90 of pregnant cows (n = 5 each). Progesterone level in d-60 CL was not different from those in d 6 to 13 CL and d-90 CL, although the difference between d 6 to 13 and d-90 was significant. In Experiment 2, protein expression pattern in CL at d-90 (n = 4) was compared with that in CL of cyclic cows at d 6 to 13 (n = 5). Significant changes in the level of protein expression were detected in 32 protein spots by two-dimensional polyacrylamide gel electrophoresis (2-DE), and 23 of them were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Six proteins were found only in pregnant CL, while the other 17 proteins were found only in cyclic CL. Among the above 6 proteins, vimentin which is involved in the regulation of post-implantation development was included. Thus, the protein expression pattern in CL was disorientated from cyclic luteal phase to mid pregnancy, and alterations in specific CL protein expression may contribute to the maintenance of pregnancy in Korean native cows.