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      • 육우 햄에 대한 소비자 선호 분석

        박종섭, 최양일, 공기서, 여순식 忠北大學校 農業科學硏究所 2012 農業科學硏究 Vol.28 No.3

        The purpose of this study is to estimate the implicit prices and consumers’ preference by attributes on Korean beef cattle ham using choice experiments. Main attributes are the country of origin, non-antibiotic certification, HACCP certification, addition of Korean agricultural products and use of natural colors. The implicit prices of each attribute and level for country of origin are estimated as KRW 919.0 for Korean pork, KRW 2,173. for imported beef and KRW 5,232.9 for Korean cattle beef. The other estimated implicit prices are KRW1,762.9 for non-antibiotic certification, KRW 577.5 for HACCP certification, KRW 57.9 for addition of Korean agricultural products and finally, KRW 572.9 for use of natural colors. This study is expected to contribute to the decision-making process of Korean beef cattle farmers by providing useful quantitative information on attributes and price that are related to consumers’ preference on Korean beef cattle ham.

      • DSP를 이용한 정밀속도제어 SRM의 고효율 구동

        김창섭,최기영,안진우,표성영 경성대학교 공학기술연구소 1999 공학기술연구지 Vol.6 No.-

        본 논문에서는 맥동토오크와 부하토오크의 변화로 인한 속도변동을 줄이기 위해 동적 도통각 제어 원리를 이용한 PLL(Phase Locked Loop) 속도제어 방식을 채택하였다. SRM 구동 시스템에 적용한 결과 전동기는 강인한 정속도 운전을 할 수 있으며, 또한 선행각을 조정함으로서 고효율 구동을 할수 있었다. 구성된 시스템은 운전속도와 부하의 변화에 따라 선행각이 증감함으로써 뛰어난 동적 속도제어 특성을 갖고 있으며, 인버터 인가전압을 제어하여 선행각을 조정함으로서 전부하 영역에서 높은 효율특성을 가진다. SRM 구동 시스템의 PLL 속도제어와 고효율 제어를 위한 도통각제어를 위해 TMS320F240 DSP를 사용해 구현함으로서 디지털 제어기를 유연성과 소형화를 꾀하였다. Switched Reluctance Motor(SRM) drive system is known to provide good torque characteristics and high efficiency drive. However, speed variation caused by higher torque ripple is one of main drawback. The Phase-Locked Loop(PLL) technique in conjunction with dynamic dwell angle control has good speed regulation characteristics. In this paper, appropriate advance angle control for high efficiency drive and PLL technique for accurate speed control is proposed. A TMS320F240DSP is used to realize this drive system. Test results show that the system has good dynamic and precise speed control ability as well as high efficiency.

      • SCOPUSKCI등재
      • SCOPUSKCI등재
      • 아리스톨로크산 함유 생약제에 대한 안전성평가연구 : 3개월간 반복투여독성시험을 통한 신장독성평가

        황명실,박미선,문지영,이지선,염영나,이효민,신동환,강진석,윤은경,최미나,육미영,장동덕,길광섭,김승희,양기화 식품의약품안전청 2001 식품의약품안전청 연보 Vol.5 No.-

        본 실험에서는 아리스톨로크산을 함운하고 있는 생약제중 하나인 마두령(.4risfoforfioe JTurruf)의 90일 반복투여독성시헌을 실f,」하였다. 마두령에서 아리스톨로크산을 정량분석한 결과 마두령 단일 건조븐말의 경운 2.112mg/g, 잉상에서 처방되고 있는 마든령복방 (마두령외 9가지 생약제 복합처방) 건조분말꼭 경무에는 0.066m9/5으로 각각 검출되었다. 본 실험에서 용량설정은 마두령 처리군 (저용량 군; 21.3m9/k9/day (임상용량), 중용량군; 2t3mgfg/day, 고용량군; 2430mg딘g b.w./day), 마두령복방 처리군 (427mg/kg b.w./da?; 임상용량) 및 positive control (아리스톨로크산) 처리군 (저용량군;0.05mgag/da17, 중용량군; 0.Smg/kg/day, 고용량군; 5mg./kg/dal·1으료 하여 랫드에게 경구투여하였다. 마두령단방 처궈근 및 마두령복방 처리군에서 저용량군과 중응량군에서는 잉상관찰 및 생화학적 분석에서 패조군과 유의적인 차이가 없었다. 그러나 마두령단방 고용량근에서는 간, 신장의 상대적인 무계가 증가되었고, 신장의 유두이행상피증식 및 암종이 관찰되었으며, 위에서는 편평세포암종이 관찰되었다. 하자만 간손상이나 간암은 유발하지는 않는 것으로 판단되었다. 결론끌으로 본 실험의 결과에서는 아리스톨로크산 함유 생약제인 마두령이 임상용량인 저응량 처리군에서는 독성을 나타내지 않았으나, 고용쏭으로 장기 복용시켰을 깅우 설치류의 전위부위 및 신장에서 독성이 있음을 알 수 있었다. Chines herbs nephropathy (CHN) has been described in young women who had taken a slimming pills containing some chines herbs. Aristolochic acid (AA), suspected substance as the causal factor of CHN, is known a carcinogen. The Aristolochiae fructus (fruit of Aristolochia contorta) was used in Korean Traditional Medicine consists of appropriate amounts of mixed natural products. Subchronic toxicity of A. furctus containing aristolochic acid was investigated in SD rats. The body weight and clinical signs were observed after orally administration of A. futctus at doses of 21.2, 213, and 2130 mg/kg/day; mixture (including 9 other herbs) at dose of 427 mg/kg/day; aristolochic aicd (Ⅰ+Ⅱ) at doses of 0.05, 0.5, and 5 mg/kg/day for 3 months. At the end of the treatment, high dose treated animals revealed a deficit in final body weight about 25% compared with that of control. Organ weights of kidney, liver, testis, or ovary were increased with dose dependent manner. No changes considered to be due to the administration of A. furctus, mixture or aristolochic acid were in hematological and clinical study. However, significant changes at histopathological study of kidney and stomach were boserved in high-dose treated groups. In conclusion, for human health safety it needs appropriate regulatory actions regarding the use of natural herbal medicines known or suspected of containing aristolochic acid.

      • SCISCIESCOPUS

        Removal of carbon dioxide by absorption into blended amines: kinetics of absorption into aqueous AMP/HMDA, AMP/MDEA, and AMP/piperazine solutions

        Choi, Won-Joon,Cho, Ki-Chul,Lee, Sang-Sup,Shim, Jae-Goo,Hwang, Hye-Ryun,Park, Sang-Wook,Oh, Kwang-Joong Royal Society of Chemistry 2007 GREEN CHEMISTRY Vol.9 No.6

        <P>The emissions of anthropogenic carbon dioxide (CO<SUB>2</SUB>) are believed make a significant impact on global climate change. Hence, amine chemical absorption technology has been suggested to separate and recover CO<SUB>2</SUB>. In this study, reaction rate constants between CO<SUB>2</SUB> and blended amines were determined by measuring their absorption rate for CO<SUB>2</SUB>. The experiments were carried out to investigate the characteristics of CO<SUB>2</SUB> absorption by using additional absorbents such as hexamethylenediamine (HMDA), <I>N</I>-methyldiethanolamine (MDEA) or piperazine blended into 2-amino-2-methyl-1-propanol (AMP) in an agitated vessel. The absorption rates of CO<SUB>2</SUB> into aqueous blended amine solutions were measured. Additive concentrations of 1, 3, and 5 wt% were added for each 30 wt% AMP solution. The results showed that the addition of HMDA, MDEA or piperazine into AMP increased the absorption rate as compared to AMP alone. Of these additives, HMDA showed the most enhancement in the reaction rate of AMP. The reaction rate constants of HMDA, MDEA and piperazine blended into AMP at 303–343 K were given by <I>k</I><SUB>H</SUB> = 3.84 × 10<SUP>10</SUP>exp(−5361/<I>T</I>), <I>k</I><SUB>M</SUB> = 6.60 × 10<SUP>9</SUP>exp(−4959/<I>T</I>), and <I>k</I><SUB>P</SUB> = 9.09 × 10<SUP>9</SUP>exp(−5058/<I>T</I>), respectively.</P> <P>Graphic Abstract</P><P>The addition of 1, 3, and 5 wt% HMDA, MDEA or piperazine into 30 wt% AMP increased the absorption rate as compared to AMP alone. The reaction rate constants of HMDA, MDEA and piperazine blended into AMP at 303–343 K were given by <I>k</I><SUB>H</SUB> = 3.84 × 10<SUP>10</SUP> exp(−5361/<I>T</I>), <I>k</I><SUB>M</SUB> = 6.60 × 10<SUP>9</SUP> exp(−4959/<I>T</I>), and <I>k</I><SUB>P</SUB> = 9.09 × 10<SUP>9</SUP> exp(−5058/<I>T</I>), respectively. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b614101c'> </P>

      • KCI등재후보

        갑상선 종양에서 Heat Shock Protein70과 Heat Shock Protein90의 발현 양상

        최진욱,김진영,박철영<SUP>1<.SUP>,오기원<SUP>1<.SUP>,임성희<SUP>1<.SUP>,박성우<SUP>1<.SUP>,조현득<SUP>2<.SUP>,이명준<SUP>3<.SUP>,김이수,Jin Wook Choi,M.D.,Jin Yong Kim,Cheol Young Park,M.D.<SUP>1<.SUP>,Ki Won Oh,M.D.<SUP>1<.SUP> 대한갑상선-내분비외과학회 2004 The Koreran journal of Endocrine Surgery Vol.4 No.2

        Purpose: Heat shock proteins (hsps) are synthesized by cells in response to various stress conditions, including carcinogenesis. The expression of hsps in neoplasia has been implicated in the regulation of cell signaling pathway such as cell survival and apoptosis. This study aimed to determine whether hsps expression in various thyroid neoplasia are significant and to identify the possibility as a therapeutic molecular target. Methods: We examined the expression of the hsp70 and hsp90 on tissue section from 53 thyroid tissues (16 normal tissues; 11 nodular hyperplasia; 12 follicular adenomas; 14 papillary carcinomas) using immunohistochemistry. Hsps expression was scored according to the percentage of positively stained cells (grade 0 to grade III). Results: For hsp70, all of the 53 tissues showed over- expression. 100% (16/16) of normal thyroid tissue and 87.0% (20/23) of benign tissue were categorized as grade I or II. In comparison, the carcinoma tissues showed expression in 64.3% with grade III. For hsp90, almost of normal thyroid tissue and benign tumors showed no expression (87.5% in normal tissues, 91.3% in benign tumors). However, all of carcinoma tissues showed expression and 78.6% (11/14) of carcinoma were in grade II or III. Conclusion: In current study, the pattern of expression for hsp70 and hsp90 in normal, benign, malignant thyroid tissues suggests that heat shock proteins might have some role in tumorigenesis in thyroid. Since there have been no reports on heat shock proteins and thyroid, further study is necessary and could give us clinically significant clue for diagnosis and treatment. (Korean J Endocrine Surg 2004; 4:79-84)

      • Enhanced Patency and Endothelialization of Small-Caliber Vascular Grafts Fabricated by Coimmobilization of Heparin and Cell-Adhesive Peptides

        Choi, Won Sup,Joung, Yoon Ki,Lee, Yunki,Bae, Jin Woo,Park, Han Ki,Park, Young Hwan,Park, Jong-Chul,Park, Ki Dong American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.7

        <P>The clinical utility of a small-caliber vascular graft is still limited, owing to the occlusion of graft by thrombosis and restenosis. A small-caliber vascular graft (diameter, 2.5 mm) fabricated by electrospinning with a polyurethane (PU) elastomer (Pellethane) and biofunctionalized with heparin and two cell-adhesive peptides, GRGDS and YIGSR, was developed for the purpose of preventing the thrombosis and restenosis through antithrombogenic activities and endothelialization. The vascular grafts showed slightly reduced adhesion of platelets and significantly decreased adsorption of fibrinogen. In vitro studies demonstrated that peptide treatment on a vascular graft enhanced the attachment of human umbilical vein endothelial cells (HUVECs), and the presence of heparin and peptides on the graft significantly increased the proliferation of HUVECs. In vivo implantation of heparin/peptides coimmobilized graft (PU-PEG-Hep/G+Y) and PU (control) grafts was performed using an abdominal aorta rabbit model for 60 days followed by angiographic monitoring and explanting for histological analyses. The patency was significantly higher for the modified PU grafts (71.4%) compared to the PU grafts (46.2%) at 9 weeks after implantation. The nontreated PU grafts showed higher levels of alpha-SMA expression compared to the modified grafts, and for both samples, the proximal and distal regions expressed higher levels compared to the middle region of the grafts. Moreover, immobilization of heparin and peptides and adequate porous structure were found to play important roles in endothelialization and cellular infiltration. Our results strongly encourage that the development of small-caliber vascular grafts is feasible.</P>

      • SCOPUSKCI등재

        Fabrication of Endothelial Cell-Specific Polyurethane Surfaces co-Immobilized with GRGDS and YIGSR Peptides

        Choi, Won-Sup,Bae, Jin-Woo,Joung, Yoon-Ki,Park, Ki-Dong,Lee, Mi-Hee,Park, Jong-Chul,Kwon, Il-Keun The Polymer Society of Korea 2009 Macromolecular Research Vol.17 No.7

        Polyurethane (PU) is widely used as a cardiovascular biomaterial due to its good mechanical properties and hemocompatibility, but it is not adhesive to endothelial cells (ECs). Cell adhesive peptides, GRGDS and YIGSR, were found to promote adhesion and spreading of ECs and showed a synergistic effect when both of them were used. In this study, a surface modification was designed to fabricate an EC-active PU surface capable of promoting endothelialization using the peptides and poly(ethylene glycol) (PEG) spacer, The modified PU surfaces were characterized in vitro. The density of the grafted PEG on the PU surface was measured by acid-base back titration to the terminal-free isocyanate groups. The successful immobilization of pep tides was confirmed by amino acid analysis, following hydrolysis, and contact angle measurement. The uniform distribution of peptides on the surface was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). To evaluate the EC adhesive property, cell viability test using human umbilical vein EC (HUVEC) was investigated in vitro and enhanced endothelialization was characterized by the introduction of cell adhesive peptides, GRGDS and YIGSR, and PEG spacer. Therefore, GRGDS and YIGSR co-immobilized PU surfaces can be applied to an EC-specific vascular graft with long-term patency by endothelialization.

      • KCI등재

        적출관류 간에서 대황, 마황 및 황금이 7-에톡시쿠마린의 대사에 미치는 영향

        최기환(Ki Hwan Choi),김순선(Soon Sun Kim),박윤주(Youn Joo Park),정혜주(Hye Joo Chung),안미령(Mee Ryung Ahn),서수경(Soo Kyung Suh),신윤용(Yhun Yhong Sheen),김동섭(Dong Sup Kim),장영섭(Young Sup Chang) 대한약학회 1998 약학회지 Vol.42 No.4

        In order to study the effects of Rhei rhizoma, Ephedrae herba and Scutellariae radix on hepatic metabolism, we examined the pretreatment effect of those on the metabolism of 7-ethoxycoumarin (EC). Water extracts (1g/kg) of Rhei rhizoma, Ephedrae herba and Scutellariae radix were administered orally to rats for 7 days, respectively. Livers were then isolated and perfused with 100mcM EC for 2 hours. The metabolites of EC, 7-hydroxycoumarin, sulfate conjugate and glucuronide conjugate were measured in the perfusates. The amount of glucuronide conjugates was decreased in Rhei rhizoma pretreated rats (p<0.01), however. 7-hydroxycoumarin was increased in Ephedrae herba pretxeated rats (p<O.OD. We examined whether the change of enzyme activity is related to the change of cytochrome P4501A1 a n d P4502B1 mRNA level in the perfused rat liver, which are responsible for EC metabolism. CYPlAl a n d CYP2B1 mRNA level was increased, which was not statistically significant with rhei rhizoma nor ephedrae herba pretreatment. We also assessed the hepatotoxicity of Rhei rhizoma. Ephedrae herba a n d Scutellariae radix. The activities of ALT and AST were assayed at 24 hours after 7 days administration. Only the ratio of ALT over AST was increased in ephedrae herba pre treated rats (p<0.05). Lipid peroxidation was increased in Rhei rhizoma treatment (p<0.05). while histopathological examination performed after liver perfusion did not show a n y difference compared with vehicle treatment. These results suggest that Ephedrae herba pretreatment increases the o-deethy-lation of 7-ethoxycoumarin in rats, which may be mediated b y CYPlAl mRNA induction.

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