• Macromolecular Research
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• v.13 no.2
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• pp.114-119
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• 2005

We synthesized two new series of alternating copolymers, poly[bis(2-(4-phenylenevinylene)-2-cyanoethenyl)-9,9-dihexyl-9H-fluoren-2,7-yl-alt-1,4-phenylene](Polymer-I)and poly[bis(2-(4-phenylenevinylene)-2­cyanoethenyl)-9,9-dihexyl-9H-fluoren-2,7-yl-alt-2,7-(9,9-dihexylfluorene)](Polymer-II), via the Suzuki coupling reaction, for use in light-emitting diodes (LEDs). Defect-free uniformly thin films of these polymers were found to be easily formed on indium-tin oxide (ITO) coated glass substrates. Multi-layer LEDs with ITO/PEDOT/Polymer/ LiF/Al configurations with or without an $Alq_3$ electron transport layer were fabricated with these polymers. The maximum EL emissions of Polymer-I and Polymer-II with an $Alq_3/LiF/Al$ cathode were observed at 516 and 533 nm, respectively. The maximum brightness and external luminance efficiency of the devices fabricated with the EL polymers were found to be $411 cd/m^2$ and 0.16 cd/A, respectively.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.6
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• pp.48-55
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• 2001

This paper presents a 1.8 GHz CMOS frequency synthesizer with high-speed on-chip pseudo 2-stage ring VCO. We introduce and analysis the conditions in which the ring VCO can oscillate. For high speed operation, we propose the pseudo 2-stage ring VCO that eliminates dummy loads. It can operate up to 1.87 GHz with 0.6 m CMOS process, which shows 21.3% improvement aginst the conventional 4-stage ring VCO in the aspect of the speed. When the frequency synthsizer with the psedo 2-stage ring VCO is locked at 1.85GHz, the jitter measured to 24 psec. The proposed VCO and the frequency synthesizer are directly applicable to high speed clocky synhtesizers.

• Korean Aquaculture
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• v.14 no.2
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• pp.52-65
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• 2002

비단가리비의 인공 종묘 생산을 목적으로 전라남도 신안군 대흑산도 주변에 서식하는 비단가리비를 대상으로 인공 종묘 생산을 위한 산란 유발, 수정란의 발생 과정, 유생 사육, 채묘 및 중간 육성 등 양식 생물학적 연구를 실시하였다. 어미의 각종 산란 유발 자극에 대한 반응은 Serotonin 주사, 온도 자극, 혼합 자극에서 반응율이 가장 높았으며, 자외선 조사 해수 자극은 수컷만 반응을 하였고 간출 자극은 반응이 없어 실효성이 없는 것으로 나타났다. 수정란의 크기는 $69.5{\mu}m$이었고, 수정 후 약 2시간에 2 세포기, 8시간 후에 8 세포기, 20시간 후에는 담륜자 유생으로 부화하였으며 40시간 후에는 D상 유생으로 되었다. 수온별 비단가리비 유생의 성장은 수온 $20^{\circ}C$에서 각장 $178.9{\mu}m$로 가장 좋았으며, 이 때의 생존율은 15.5%이었다. 그러나 수온 $15^{\circ}C$에서는 낮은 성장을 보여 각장 $135.9{\mu}m$로 성장하였으며, 생존율도 9.8%로 저조하였다. 수용 밀도별 사육 시험에서 $1m{\ell}$당 1개체와 5개체에서 성장 및 생존율이 양호하여 성장 및 생존율을 볼 때 적정 사육 밀도는 $1m{\ell}$당 5개체 이하로 나타났다. 먹이 생물 종류에 따른 유생의 성장을 알기 위하여 I, gal-baba, C, calcitrans, N, oculata를 단독 또는 혼합으로 공급하였을 때 실험 종료후 각장의 성장은 I, galbana+C. calcitrans+N. oculata구가 $194.2{\mu}$로 가장 좋았고 N. oculata구는 $162.2{\mu}m$로 가장 낮은 성장을 보였다. 생존율에서는 I. galbana+C. calcitransoculata구는 9.4%로 가장 낮은 생존율을 보였다. 채묘기별 유생의 부착률은 염화비닐판을 수평으로 놓은 것과 패각이 각각 3.43%와 3.17%로 가장 양호하였으나, 양파망과 염화비닐판을 수직으로 놓은 것은 각각 1.52%와 1.61%로 비교적 저조하였다. 수정 후 40일째부터 90일째까지 측정한 부착치패의 경과 일수에 따른 각장의 성장은 $SL=184.44e^{0.0335X}(r^2=0.9861)$의 회귀직선식으로서 나타났다. 중간육성 시험에서 수심별 성장을 분석한 결과, 비단가리비 치패는 저층보다 표층이 각장 5.92mm, 전중량 6.07g 정도 더 빨리 성장하였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.32-37
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• 1999

The experiment was conducted to investigate emergence response of lowland weeds at different soil moisture contents, burying depths and upon changes in soil moisture. Rice germination was over 50% at all burying depths under aerobic condition, but the emergence rate of the soil surface placed seeds in saturated and flooded conditions decreased by 19% and 29%, respectively, as compared with that of aerobic condition. Rice seeds at burying depth of over 3 cm did not emerge at all. The emergence rate of Echinochloa crus­galli (L.) Beauv. in aerobic condition was lower than 30%, but the emergence pattern of E. crus galli (L.) Beauv. at different soil moisture contents and seeding depths was similar to that of rice. Emergence behavior of lschaemum rugosum Salisb., Ludwigia octovalvis (Jacq.) Raven and Sphenoclea zeylanica Gaertn. which are dominant lowland weed species in the Philippines also differed depending on soil moisture conditions and burying depths. lschaemum rugosum Salisb. emerged at all burying depths under aerobic condition, whereasLudwigia octovalvis (Jacq.) Raven emerged only at 0 cm deep under saturated and aerobic condition and Sphenoclea zeylanica Gaertn. at 0 cm deep under flooding condition. Weed seeds planted at 1, 3, and 5 cm deep in continuous flooded and saturated condition did not emerge at all, but upon a change of soil moisture condition from saturated to drainage (S$\rightarrow$D) and flooded to drainage (F$\rightarrow$D), grass weeds began to germinate again and the average emergence rate in S$\rightarrow$D and F$\rightarrow$D were 26% and 5% forE. crus­galIi (L.) Beauv., 9% and 8% forI. rugosum SaIisb., respectively. Weed seeds buried in soil in the pot showed great emergence at S$\rightarrow$D but did not emerge under continuous flooded condition. The diversity index accounting for dominance degree and occurrence aspect of weed, was the lowest at F$\rightarrow$D.

• The Journal of Internal Korean Medicine
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• v.34 no.3
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• pp.240-255
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• 2013

Objectives : This study was performed to research trends in Korean medicine treatment of diabetes mellitus (DM). Methods : We reviewed 73 studies about diabetes mellitus, which had been published from 2008 to 2013. The article search was performed on the Korean institute of oriental medicine (KIOM) database. Results : 1. Patterns of study design were as follows : 14 review studies, 44 experimental studies, 7 clinical studies, 8 case reports. 2. From the 14 review studies, we noted that literature studies about definition, pathologic mechanism, treatment, pathologic pattern identification of DM and previous study analyses were done. 3. From the 44 experimental studies that are the most common type of DM studies, various Korean medicine treatments such as single medicinal herbs, herbal complexes, diets and pharmacopuncture were used. Anti-diabetic effects were demonstrated in most of the studies. 4. 7 clinical studies about acupuncture, electroacupuncture, herbal medicine, etc. were reported. 5. 8 cases about DM complications and comorbidities were reported. Clinical symptoms improved in all of studies, blood sugar level decreased in four studies. Conclusions : Further clinical and case study based on experimental researches should be performed.

• Korean Journal of Head & Neck Oncology
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• v.15 no.2
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• pp.200-204
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• 1999

Objectives: Injuries of neurologic structures during parotid surgery are sometimes unavoidable even in benign tumors. Since the major postoperative neurologic complications such as facial nerve palsy and Frey's syndrome give a serious and heavy burden to both patients and surgeons, it is very important to know detailed information concerning risk factors, the incidence of complication, possibility of recovery, and the term before complete recovery. Materials and Methods: This report was based on 95 patients with parotid gland tumor who had been treated and followed up over 1 year at department of surgery and otolaryngology, chonnam university hospital. Results: 1) Among total 95 cases, the facial nerve palsy developed in 18 cases(l8.9%) and Frey's syndrome in 6 cases(6,3%). 2) The incidence of facial nerve palsy increased in cases with large tumor size, and in those operated with bipolar method. However, we didn't find out relationships between the incidence of facial palsy, localization, and histologic type. 3) The incidence of Frey's syndrome showed an increasing tendency in the cases with large tumor size, benign nature, and in those underwent superficial lobectomy with posterior approach, without a statistical significance. Conclusions: Risk of facial nerve palsy, especially a transient form, seems to be related to tumor size and bipolar coagulation method. Although Frey's syndrome tends to develop easily in the cases treated with superficial lobectomy under the diagnosis of benign tumor, a futhermore study is suggested to obtain a statistical significance.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.102-110
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• 2006

Background: Dendritic cells (DC) are professional antigen-presenting cells in the immune system and can induce T cell response against virus infections, microbial pathogens, and tumors. Therefore, immunization using DC loaded with tumor-associated antigens (TAAs) is a powerful method of inducing anti-tumor immunity. For induction of effective anti-tumor immunity, antigens should be efficiently introduced into DC and presented on MHC class I molecules at high levels to activate antigen-specific $CD8^+$ T cells. We have been exploring methods for loading exogenous antigens into APC with high efficiency of Ag presentation. In this study, we tested the effect of the cationic liposome (Lipofectin) for transferring and loading exogenous model antigen (OVA protein) into BM-DC. Methods: Bone marrow-derived DC (EM-DC) were incubated with OVA-Lipofectin complexes and then co-cultured with B3Z cells. B3Z activation, which is expressed as the amount of ${\beta}$-galactosidase induced by TCR stimulation, was determined by an enzymatic assay using ${\beta}$-gal assay system. C57BL/6 mice were immunized with OVA-pulsed DC to monitor the in vivo vaccination effect. After vaccination, mice were inoculated with EG7-OVA tumor cells. Results: BM-DC pulsed with OVA-Lipofectin complexes showed more efficient presentation of OVA-peptide on MHC class I molecules than soluble OVA-pulsed DC. OVA-Lipofectin complexes-pulsed DC pretreated with an inhibitor of MHC class I-mediated antigen presentation, brefeldin A, showed reduced ability in presenting OVA peptide on their surface MHC class I molecules. Finally, immunization of OVA-Lipofectin complexes-pulsed DC protected mice against subsequent tumor challenge. Conclusion: Our data provide evidence that antigen-loading into DC using Lipofectin can promote MHC class I- restricted antigen presentation. Therefore, antigen-loading into DC using Lipofectin can be one of several useful tools for achieving efficient induction of antigen-specific immunity in DC-based immunotherapy.

• Korean Journal of Community Nutrition
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• v.11 no.5
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• pp.587-597
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• 2006

This study was performed in order to identify nutritional factors affecting on skin sebum content with 131 female university undergraduates in 2003. We measured the sebum contents of 4 facial spots to classify their skin types. Daily energy and nutrient intakes of the subjects were not deficient except in calcium and iron, which were 466.2 mg (66.6% RDA) and 8.5 mg (53.4% RDA) relatively. We observed no significant difference of energy and nutrient intakes among the 3 skin types. But significantly higher consumption of grains and slightly higher frequencies of several food groups (excepting starches) were shown in oily skin types, so they might have higher nutrient intakes. Serum indices and food preferences mostly revealed no difference among the 3 skin types. But in the oily skin type, serum phosphorus levels were significantly lower than others, suggesting phosphorus-rich food consumption like soft drinks and pains could lead to a dry skin type rather than an oily one. Also in the oily skin type, sweet taste preference was slightly tower than others; more-over, sweet intake was lower samely significantly. There was mostly no significant relationship between facial sebum contents and nutrient intakes, dietary behavior, food frequency and food preference except in some factors. Animal protein intake showed a significant negative relationship toward facial sebum content. On the other hand, in normal skin type, Fishes consumed was slightly higher than others, so that higher animal protein consumption presumably leads to normal skin type. Frequency of fried food and bacon and preference of fried foods showed slightly negative relationships toward facial sebum content. Regular meal times showed significantly increased facial sebum content.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.259-266
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• 2011

Project owner, asbestos removal specialist, experts on asbestos removal work, as counter parts to be defined in the study to make out research goals have been asked with questionnaire survey and replied with 65, 275, 32 cases, respectively. And additionally, direct interview 73 sheets have been collected to find out current status of required engineers and equipments assigned and provided to the field, from them, three(3) concerned parties. Questionnaire subjects are composed of common items, reasonable unit cost, need of separate contract-awarding system, status of performing standard contract, status of providing legal engineers and equipments. Concentrated review of two~three questions by subject has been made to find out and compare idea results between three(3) concerned parties. First, legal and practical work status survey have been made to determine reasonability of introducing separate contract-awarding system, as a part of ensuring reasonable unit work cost. And then, two different status have been compared and there is introduction possibility of separate contract-awarding system, it is found out. The possibility of separate contract also has been confirmed by comparison of domestic legal grounds. Justificating grounds to introduce separate contract-awarding system have been shown. Standard contract status between asbestos removal specialists has been compared using two cases of providing removal work contract and receiving it. It is shown that case of 50 percent or less contains 38.5% when they receive contract, but only 10 percent reduction of original contract amount has been made when they provide it. It means that asbestos removal specialists do not keep occupational safety and health regulations.

• Korean Journal of Plant Taxonomy
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• v.49 no.3
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• pp.253-260
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• 2019

The plant names Hwangjeong and Wiyu were written in Chinese characters in Hyang-yak-jib-seong-bang during the early Chosen dynasty. However, soon after, Hwangjeong and Wiyu were written in Korean characters as Jukdae and Dung-gul-re, respectively. However, since under the Japanese imperialist period in Korea, the taxonomic identities of these two Korean names have been incorrectly understood, with scientific names incorrectly assigned as well to these two names thus far. The results of the present study prove that Hwangjeong is Polygonatum sibiricum and that its Korean name should be Jukdae, its initial Korean name, and not Cheung-cheung-gal-go-ri-dung-gul-re, as used recently. Meanwhile, during the Japanese imperialist period, Wiyu was termed P. officinale or P. japonicum with the Korean name of Dung-gul-re. However, the correct scientific names were shown to be synonyms of P. odoratum.