Smooth backfitting in generalized additive models

Yu, K.,Park, B.U.,Mammen, E. IMS INSTITUTE OF MATHEMATICAL STATISTICS 2008 The Annals of statistics Vol.36 No.1

Solution structure of a cathelicidin-derived antimicrobial peptide, CRAMP as determined by NMR spectroscopy

Yu, K.,Park, K.,Kang, S.-W.,Shin, S.Y.,Hahm, K.-S.,Kim, Y. 부산대학교 유전공학연구소 2002 분자생물학 연구보 Vol.18 No.-

CRAMP was identified from a cDNA clone derived from mouse femoral marrow cells as a member of cathelicidin-derived antimicrobial peptides. This peptide shows potent antimicrobial activity against gram-positive and gram-negative bacteria but no hemolytic activity against human erythrocytes. CRAMP was known to cause rapid permeabilization of the inner membrane of Escherichia coli. In this study, the structure of CRAMP adopts a mainly x-helical conformation in TFE/H_2O solution, DPC micelles, SDS micelles and liposomes, whereas it has a random structure in aqueous solution. The tertiary structure of CRAMP in TFE/H_2O (1:1, v/v), as determined by NMR spectroscopy, consists of two amphipathic α-helices from Leu^4 to Lys^10 and from Gly^16 to Leu^33. These two helices are connected by a flexible region from Gly^11 to Gly^16. Previous analysis of series of fragments composed of various portion of CRAMP revealed that an 18-residue fragment with the sequence from Gly^16 to Leu^33 was found to retain antibacterial activity. Therefore, the amphipathic x-helical region from Gly^16 to Leu^33 of CRAMP plays important roles in spanning the lipid bilayers as well as its antibiotic activity. Based on this structure, novel antibiotic peptides having strong antibiotic activity, with no hemolytic effect will be developed.

Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis

Yu, K‐,H.,Hong, K‐,S.,Lee, B‐,C.,Oh, M‐,S.,Cho, Y‐,J.,Koo, J‐,S.,Park, J‐,M.,Bae, H‐,J.,Han, M‐,K.,Ju, Y‐,S.,Kang, D‐,W.,Appelros, P. Blackwell Publishing Ltd 2011 Acta neurologica Scandinavica Vol.123 No.5

<P>Yu K‐H, Hong K‐S, Lee B‐C, Oh M‐S, Cho Y‐J, Koo J‐S, Park J‐M, Bae H‐J, Han M‐K, Ju Y‐S, Kang D‐W, Appelros P, Norrving B, Terent A. Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis. 
Acta Neurol Scand: 2011: 123: 325–331. 
© 2010 John Wiley & Sons A/S.</P><P><B>Background – </B> It has not been clarified whether the disparity in ischemic stroke outcome between populations is caused by ethnic and geographic differences or by variations in case mix. Propensity score matching (PSM) analysis can overcome some analytical problems but is rarely used in stroke outcome research. This study was to compare the ischemic stroke case‐fatality between two PSM cohorts of Sweden and Korea.</P><P><B>Methods – </B> Prognostic variables related to baseline characteristics and stroke care were included in our PSM model. Then, we selected 7675 Swedish and 1220 Korean patients with ischemic stroke from each stroke registers and performed one‐to‐one matching based on propensity scores of each patient.</P><P><B>Results – </B> After PSM, all measured variables were well balanced in 1163 matched subjects, and the 90‐day case‐fatality was identical 6.2% (HR 0.997, 95%CI 0.905–1.099) in Sweden and Korea.</P><P><B>Conclusions – </B> No difference is found in the 90‐day case‐fatality in propensity score‐matched Swedish and Korean patients with ischemic stroke.</P>

Efficient planning of NPC cluster movement in computer game environment

Springer Science + Business Media 2015 CLUSTER COMPUTING Vol.18 No.1

Relationship between the tertiary structures of mastoparan B and its analogs and their lytic activities studied by NMR spectroscopy

Yu, K.,Kang, S.,Park, N.,Shin, J.,Kim, Yangmee 부산대학교 유전공학연구소 2000 분자생물학 연구보 Vol.16 No.-

Mastoparan B (MP-B), an antimicrobial cationic tetradecapeptide amide isolated from the venom of the hornet Vespa basalis, is an amphiphilic x-helical peptide. MP-B possesses a mariety of biological activities, such as mast cells degradation histamine release, erythrocyte lysis and inhibition of the growth of Gram-positive and Gram-negative bacteria. In order to study the relationship between the structure and the biological activity of MP-B, we used four analogs by replacing amino acids with alanine. Tertiary structures of MP-B and its analogs in 2,2,2-trifluoroethanol (TFE)-containing aqueous solution have been determined by NMR spectroscopy and molecular modeling. The results indicate that [Ala^4]MP-B and [Ala^12]MP-B with higher hydrophobicity adopt a higher content of amphiphilic helical structures, and have better antimicrobial and hemolytic activities than MP-B. However, [Ala^3]MP-B and [Ala^9]MP-B and hydrophobicity have disordered structures. [Ala^3]MP-B and [Ala^9]MP-B have low antimicrobial activity and much less hemolytic activity relative to MP-B. It is likely that tryptophan residue in MP-B and appropriate hydrophobicity of MP-B to induce x-helical structure is essential for the antibacterial and hemolytic activity of MP-B. This study can aid understanding of the structure-activity relationship of MP-B and to design peptides to possess lytic activity.

공압작동식 랙-피니언 회전실린더의 성능개선 연구

이역규,남효덕 嶺南大學校 工業技術硏究所 2002 工業技術硏究所論文集 Vol.30 No.2

This paper describes the performance of the rack-pinion rotating cylinder after the material of the piston gear was substituted aluminum alloy for nylon plastic with 30 % glass fiber. The on-off control system of rack-pinion rotating cylinder was designed for measuring output torque, efficiency and on-off time depending on working pressure and inner radius of cylinder. By replacing aluminum alloy with nylon plastic, of this research results showed the output torque enhancement by 0.5∼3.0 %, the on-off time reduction by 0.1∼2.0 second, and the efficiency improvement by 0.2∼1.8 %. Improving output torque from ths research enabled rack-pinion rotating cylinder to small size and reduction of the on-off time enlarged the range of speed regulation.

獻花歌의 硏究

劉六禮 한국고시가문학회 2003 한국시가문화연구 Vol.0 No.12

This is a study on a collection of songs named Hun-hwa-ga. It mainly examined a status of the writer and a symbolic meaning of a flower named Chuk-chok-hwa. Il-yeon, a monk, collected poems and published them in a book titled Hun-hwa-ga. Therefore, this study connected the two subjects with buddhism. So far, the writer has been considered as a Taoist, a hermit a monk or Buddha. This study considered the writer as Buddha as it is believed that humans are not able to pick flowers on the cliff. And Il-yeon is not a hermit or Taoist as he is a Buddhist. So, Gyeon-woo-no-ong was thought as Buddha. The flower on the cliff is such a lolly world that anyone can not approach. The world is the land of happiness and peace without suffering which was pursued by Silla people.

공압 회전실린더의 재질특성 연구

장호경,이역규 경산대학교 기초과학연구소 2001 基礎科學 Vol.5 No.2

본 연구에서는 공압작동식 랙-피니언 회전실린더의 피스톤 기어 재질 특성에 관하여 연구하였다. 랙-피니언 회전실린더의 동작 성능에 중요한 피스톤 기어의 재질을 알루미늄 합금에서 유리섬유가 첨가된 나일론 플라스틱으로 교체하였다. 나일론 플라스틱은 알루미늄 합금에 비해 상대적으로 낮은 비중과 가공공정의 용이성 및 원가절감의 효과를 기대할 수 있지만, 내구성에 문제가 있다. 따라서 내구성에 대한 타당성 검증과 최적의 유리섬유 첨가량을 결정하기 위해 나일론 플라스틱에 유리섬유 첨가량을 변화시켜 인장강도, 충격강도 및 굽힘 강도를 측정하였다. The characteristics of material for the piston gear of the pneumatically operated rack-pinion rotating cylinder were studied. The material of piston gear was replaced aluminum alloy with nylon plastic for the operation performance of rack-pinion rotating cylinder. The properties of nylon plastic were the low specific gravity, easiness of manufacturing process and effect of cost reduction. In this paper, the tensile strength, impact strength and flexural strength were measured according to glass fiber percentage for the feasibility inspection of the fabricated piston gear.

One-way membrane for transdermal drug delivery systems : Ⅱ. System optimization

Yuk, Soon Hong,Lee, Seung Jin,Okano, Teruo,Berner, Bret,Kim, Sung Wan 梨花女子大學校 藥學硏究所 1992 藥學硏究論文集 Vol.- No.2

Effective flux of steroid solute through skin can be achieved by the use of ethanol as a co-solvent and penetration enhancer. To maintain constant drug release from a reservoir-type transdermal device and permeation through the skin, the composition of ethanol in the reservoir must remain constant. Ethanol permeability is much higher than that of either drug or water; any decrease in ethanol content may result in decreased drug flux. In an attempt to design a transdermal delivery device with constant ethanol enhancing activity, a model system was designed with separate ethanol reservoir, drug/solvent reservoir and receiver compartments. The ethanol and drug/solvent reservoir compartments were separated by a polydimethylsiloxane copolymer laminate membrane. This 'one-way' rate-controlling membrane(Yuk et al., Int. J. Pharm., 77(1991) 2210229) optimized ethanol flux while preventing drug and water back flux. Permeation studies with model steroid solutes in this system demonstrated consistent ethanol enhancing activity with constant solute flux across the skin.

External reinforcement of hydrocarbon membranes by a three-dimensional interlocking interface for mechanically durable polymer electrolyte membrane fuel cells

Yuk, Seongmin,Yuk, Jinok,Kim, Tae-Ho,Hong, Young Taik,Lee, Dong-Hyun,Hyun, Jonghyun,Choi, Sungyu,Doo, Gisu,Lee, Dong Wook,Kim, Hee-Tak Elsevier 2019 Journal of Power Sources Vol.415 No.-

<P><B>Abstract</B></P> <P>Although, the use of hydrocarbon membranes is one of the ways to reduce the cost of polymer electrolyte membrane fuel cells, it cannot be practically adopted due to its low mechanical durability under a dynamic wet/dry operation. Here, we present an externally-reinforced hydrocarbon membrane achieved by a three dimensional interlocking interfacial layer which forms a strong interfacial bonding between the hydrocarbon membrane and the catalyst layers. Although a conventional hydrocarbon membrane is easily delaminated from gas diffusion electrodes, the use of the three dimensional interlocking interfacial layer, prepared with a polystyrene nanoparticle template method, enhances the interfacial adhesion by 207 times. The hydrocarbon membrane, tightly connected to the gas diffusion electrodes by the three dimensional interlocking interfacial layers, has a humidity cycling durability that is 1.9 times higher in the membrane electrode assembly level by restricting the dimensional change of the membrane. Furthermore, due to the proton conducting property of the three dimensional interlocking interfacial layer, the external reinforcement does not cause any power performance losses.</P> <P><B>Highlights</B></P> <P> <UL> <LI> An externally-reinforced hydrocarbon (HC) membrane is demonstrated. </LI> <LI> 3D interlocking interface tightly binds the HC membrane and gas diffusion electrode. </LI> <LI> The mechanical stability of the HC membrane is improved by 3D interlocking interface. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>