• Title/Summary/Keyword: K

Search Result 755,353, Processing Time 0.267 seconds

Studies on the Microbial Glucose Isomerase Part 1. Isolation and Characterization of Streptomyces species Producing Glucose Isomerase (미생물의 포도당 이성화효소에 관한 연구 (제1보) 포도당 이성화효소 생산균주의 분리 및 성질에 관하여)

  • Chung, Tai-Wha;Kim, Hyun U.;Moon H. Han
    • Microbiology and Biotechnology Letters
    • /
    • v.4 no.4
    • /
    • pp.138-144
    • /
    • 1976
  • five strains of Streptomyces spp. with high Productivity of glucose isomerase (15-30 units/ml) were obtained among 280 microbial strains isolated from 150 soil samples. These strains produced glucose isomerase with xylose as an inducer. These 5 strains were also identified to be different strains of Streptomyces spp.:streptomyces sp. K-14, K-53, K-71, K-77 and K-733. It was found that Streptomyces sp. K-14 produced the highest enzyme activity. The spore chains of these strains were rectiflexible and spore surface was smooth except Steptomyces sp. K-77 and K-733, with spiny surface.

  • PDF

Lignan Glycosides of Vaccinium oldhami Miquel (정금나무의 Lignan Glycoside 성분)

  • Kim, Seong-Jin;Lee, Jeong-Joo;Lee, Sa-Im;Park, Hee-Wook;Lee, Jae-Hyeok;Park, Jeong-Suk;Kim, Sung-Hoon;Baek, Nam-In;Kwon, Young-Ee;Yang, Jae-Heon;Chae, Byeong-Suk;Lim, Jong-Pil;Shin, Tae-Yong;Jeon, Hoon;Eun, Jae-Soon;Kim, Dae-Keun
    • Korean Journal of Pharmacognosy
    • /
    • v.38 no.3 s.150
    • /
    • pp.296-298
    • /
    • 2007
  • Two lignan glycoside compounds were isolated from the twigs of Vaccinium oldhami (Ericaceae) through repeated column chromatography. Their chemical structures were elucidated as lyoniside and ssioriside, respectively, by spectroscopic analysis.

The Analysis of Acoustic Emission Spectra in a 36 kHz Sonoreactor (36kHz 초음파 반응기에서의 원주파수 및 파생주파수의 음압 분포 분석)

  • Son, Younggyu
    • Journal of Soil and Groundwater Environment
    • /
    • v.21 no.6
    • /
    • pp.128-134
    • /
    • 2016
  • Acoustic emission spectra was analyzed to investigate the distribution of sound pressure in a 36 kHz sonoreactor. The sound pressure of fundamental frequency (f: 36 kHz), harmonics (2f: 72 kHz, 3f: 108 kHz, 4f: 144 kHz, 5f: 180 kHz, 6f: 216 kHz), and subharmonics (1.5f: 54 kHz, 2.5f: 90 kHz, 3.5f: 126 kHz, 4.5f: 162 kHz, 5.5f: 198 kHz, 6.5f; 234 kHz) was measured at every 5 cm from the ultrasonic transducer using a hydrophone and a spectrum analyzer. It was revealed that the input power of ultrasound, the application of mechanical mixing, and the concentration of SDS affected the sound pressure distributions of the fundamental frequency and total detected frequencies frequencies significantly. Moreover a linear relationship was found between the average total sound pressure and the degree of sonochemical oxidation while there was no significant linear relationship between the average sound pressure of fundamental frequency and the degree of sonochemical oxidation.

Effects of Prostaglandin $F_{2{\alpha}}$ on Membrane Potentials and $K^+$ Currents in Rabbit Middle Cerebral Arterial Cells

  • Kim, Na-Ri;Han, Jin;Kim, Won-Gue;Kim, Eui-Yong
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.4 no.4
    • /
    • pp.301-309
    • /
    • 2000
  • The purpose of our investigation was to examine the effects of prostaglandin $F_{2{\alpha}}\;(PGF_{2{\alpha}})$ on membrane potentials, $Ca^{2+}-activated\;K^+\;(K_{Ca})$ channels, and delayed rectifier $K^+(K_V)$ channels using the patch-clamp technique in single rabbit middle cerebral arterial smooth muscle cells. $PGF_{2{\alpha}}$ significantly hyperpolarized membrane potentials and increased outward whole-cell K currents. $PGF_{2{\alpha}}$ increased open-state probability of $K_{Ca}$ channels without the change of the open and closed kinetics. $PGF_{2{\alpha}}$ increased the amplitudes of $K_V$ currents with a leftward shift of activation and inactivation curves and a decrease of activation time constant. Our results suggest that the activation of $K_{Ca}$ and $K_V$ channels, at least in part, may lead to attenuate or counteract vasoconstriction by $PGF_{2{\alpha}}$ in middle cerebral artery.

  • PDF

Characterization of Proteus vulgaris K80 Lipase Immobilized on Amine-Terminated Magnetic Microparticles

  • Natalia, Agnes;Kristiani, Lidya;Kim, Hyung Kwoun
    • Journal of Microbiology and Biotechnology
    • /
    • v.24 no.10
    • /
    • pp.1382-1388
    • /
    • 2014
  • Proteus vulgaris K80 lipase was expressed in Escherichia coli BL21 (DE3) cells and immobilized on amine-terminated magnetic microparticles (Mag-MPs). The immobilization yield and activity retention were 84.15% and 7.87%, respectively. A homology model of lipase K80 was constructed using P. mirabilis lipase as the template. Many lysine residues were located on the protein surface, remote from active sites. The biochemical characteristics of immobilized lipase K80 were compared with the soluble free form of lipase K80. The optimum temperature of K80-Mag-MPs was $60^{\circ}C$, which was $20^{\circ}C$ higher than that of the soluble form. K80-Mag-MPs also tended to be more stable than the soluble form at elevated temperatures and a broad range of pH. K80-Mag-MP maintained its stable form at up to $40^{\circ}C$ and in a pH range of 5.0-10.0, whereas soluble K80 maintained its activity up to $35^{\circ}C$ and pH 6.0-10.0. K80-Mag-MPs had broader substrate specificity compared with that of soluble K80. K80-Mag-MPs showed about 80% residual relative activity after five recovery trials. These results indicate the potential benefit of K80-Mag-MPs as a biocatalyst in various industries.

Parallel Prefix Computation and Sorting on a Recursive Dual-Net

  • Li, Yamin;Peng, Shietung;Chu, Wanming
    • Journal of Information Processing Systems
    • /
    • v.7 no.2
    • /
    • pp.271-286
    • /
    • 2011
  • In this paper, we propose efficient algorithms for parallel prefix computation and sorting on a recursive dual-net. The recursive dual-net $RDN^k$(B) for k > 0 has $(2n_o)^{2K}/2$ nodes and $d_0$ + k links per node, where $n_0$ and $d_0$ are the number of nod es and the node-degree of the base-network B, respectively. Assume that each node holds one data item, the communication and computation time complexities of the algorithm for parallel prefix computation on $RDN^k$(B), k > 0, are $2^{k+1}-2+2^kT_{comm}(0)$ and $2^{k+1}-2+2^kT_{comp}(0)$, respectively, where $T_{comm}(0)$ and $T_{comp}(0)$ are the communication and computation time complexities of the algorithm for parallel prefix computation on the base-network B, respectively. The algorithm for parallel sorting on $RDN^k$(B) is restricted on B = $Q_m$ where $Q_m$ is an m-cube. Assume that each node holds a single data item, the sorting algorithm runs in $O((m2^k)^2)$ computation steps and $O((km2^k)^2)$ communication steps, respectively.

Knowledge on Sudden Unexplained Infant Death-related Safe Sleep Practices and Infant Cardiopulmonary Resuscitation in Pediatric Nurses

  • Cho, Jung Ae;Sohn, Min;Lee, Sangmi;Ahn, Young Mee
    • Child Health Nursing Research
    • /
    • v.26 no.4
    • /
    • pp.454-462
    • /
    • 2020
  • Purpose: Sudden unexplained infant death (SUID) is a major contributor to infant mortality, and pediatric nurses have the responsibility to educate parents on SUID-reducing strategies. This study was conducted to measure pediatric nurses' knowledge of SUID-related safe sleep practices (K-SSSP) and infant cardiopulmonary resuscitation (K-ICPR). Methods: In total, 136 pediatric nurses were administered a survey including K-SSSP (13 items), K-ICPR (5 items), confidence in K-SSSP education (1 item; 5 points), and other factors relating to SUID experiences or education. Results: The correct answer rates of the K-SSSP and K-ICPR were 62.6% and 62.5%, retrospectively. The mean score for confidence in K-SSSP education was 2.6±0.9. Only 18 nurses (13.2%) responded that they educated parents on the content of the K-SSSP, while 76 nurses had received education on SUID. Positive relationships were observed between K-SSSP scores and higher education, between K-ICPR scores and having own child(ren) and clinical experience, and between confidence in K-SSSP education and higher education or having one's own child(ren). Nurses caring for newborns performed more SUID education than nurses working in other units. Conclusion: There is a profound need to implement a systemic educational program on SUID and strategies to reduce SUID for pediatric nurses.

A 2' QCIF Flexible OTFT driven AM-OLED Display

  • Suh, Kyung-Soo;You, In-Kyu;Kang, Seung-Youl;Ahn, Seong-Deok;Oh, Ji-Young;Kim, Gi-Hyun;Baek, Kyu-Ha;Kim, Chul-Am;Hwang, Chi-Sun;KoPark, Sang-Hee;Yang, Yong-Suk;Chung, Sung-Mook;Lee, Jeong-Ik;Do, Lee-Mi;Chu, Hye-Yong;Kang, Kwang-Yong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.181-185
    • /
    • 2006
  • The flexible 2-inch AMOLED with $176{\times}144$ pixels has been demonstrated using top emission OLED driven by organic thin film transistors (OTFTs). For the development of AMOLED display on plastic substrate, we have developed several integration and unit process technologies. Through the optimization of the process based on plastic substrate, OTFT backplane with 2 transistors and 1 capacitor in a pixel has been fabricated and integrated with top emission OLED. The active addressing by OTFT driving circuit has been achieved and green light with 15 $cd/m^2$ at 15V has been observed.

  • PDF

BAFFLE DESIGN OF FIMS (과학기술위성 1호 원자외선 분광기 FIMS의 배플 설계)

  • Yuk, I.S.;Seon, K.I.;Ryu, K.S.;Jin, H.;Park, J.H;Nam, U.W.;Lee, D.H.;Oh, S.H.;Rhee, J.G.;Han, W.Y.;Min, K.W.;Edelstein, Jerry;Korpela, Eric
    • Publications of The Korean Astronomical Society
    • /
    • v.18 no.1
    • /
    • pp.87-95
    • /
    • 2003
  • FIMS (Far-ultraviolet IMaging Spectrograph) is the main payload of STSAT-1 satellite which was successfully launched on September 27, 2003. The optical system of FIMS consists of two sets of parabolic cylinder mirror, slit, ellipsoidal reflection grating, and baffle system. We designed two types of baffle system for the FIMS: FOV baffle and order baffle. FOV baffle in the mirror house controls the field of view, and the order baffle in the vacuum box blocks the rays reflected rays by different orders.

The maintenance record of the KSTAR helium refrigeration system

  • Moon, K.M.;Joo, J.J.;Kim, N.W.;Chang, Y.B.;Park, D.S.;Kwag, S.W.;Song, N.H.;Lee, H.J.;Lee, Y.J.;Park, Y.M.;Yang, H.L.;Oh, Y.K.
    • Progress in Superconductivity and Cryogenics
    • /
    • v.15 no.4
    • /
    • pp.6-9
    • /
    • 2013
  • Korea Superconducting Tokamak Advanced Research (KSTAR) has a helium refrigeration system (HRS) with the cooling capacity of 9 kW at 4.5 K. Main cold components are composed of 300 tons of superconducting (SC) magnets, main cryostat thermal shields, and SC current feeder system. The HRS comprises six gas storage tanks, a liquid nitrogen tank, the room temperature compression sector, the cold box (C/B), the 1st stage helium distribution box (DB#1), the PLC base local control system interconnected to central control tower and so on. Between HRS and cold components, there's another distribution box (DB#2) nearby the KSTAR device. The entire KSTAR device was constructed in 2007 and has been operated since 2008. This paper will present the maintenance result of the KSTAR HRS during the campaign and discuss the operation record and maintenance history of the KSTAR HRS.