• 제목/요약/키워드: Release effect

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Biotin Requirement for the Growth and Sporulation of Bacillus subtilis SNU816 in a Synthetic medium (Bacillus subtilis SNU816의 合成培地에서의 성장과 포자형성을 위한 Biotin 要求性에 관하여)

  • Lee, Oh-Hyoung
    • Korean Journal of Microbiology
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    • v.22 no.3
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    • pp.135-142
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    • 1984
  • The effect of biotin on the growth and sporulation of Bacillus subtilis SNU816 was investigated. When B. subtilis SNU816 was cultured on glucose as a sole carbon source, the growth was retarded markedly and usually ceased at early log phawe. But by addition of biotin to this medium, normal, rapid growth was restored. The growth rate was increased proportionally according to the concentration of exogenous biotin until it reached to 0.05㎍/ml, at which about three fold rapid growth was achieved. Also biotin was required for optimum sporulation for it facilitated the complete utilization of both glucose(Glc) and glutamic acid(Glu). Without biotin in Glc+Glu medium, about 40% of glutamic acid was remained unutilized. The dipicolinic acid content of cells cultured in Glc+Glu medium without biotin was markedly small and sporulation was suppressed before free spore release. Since biotin could be partiallyreplaced by one of TCA cycle intermediates such as oxalacetic acid, citric acid, or glutamic acid in enhancing growth in Glc medium, it was postulated that this strain might have a defect in converting pyruvate to oxalacetate which process is known to be mediated by pyruvate carboxylase that requires biotin as a cofactor.

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A Study of Transonic Premixed Combustion in a Diverging Channel Using Asymptotic Analysis (점근해석을 이용한 확대형 채널 내의 천음속 예혼합 연소에 관한 연구)

  • Lee, Jang-Chang
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.8
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    • pp.75-83
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    • 2005
  • A steady transonic dilute premixed combustion in a diverging channel is investigated by using asymptotic analysis. This model explores the nonlinear interactions between the near-sonic speed of the flow, the small changes in geometry from a straight channel, and the small heat release due to the one-step first-order Arrhenius chemical reaction. The reactive flow is described by a nonhomogeneous transonic small-disturbance (TSD) equation coupled with an ordinary differential equation for the calculation of the reactant mass fraction in the combustible gas. Also the asymptotic analysis reveals the similarity parameters that govern the reacting flow problem. The results show the complicated nonlinear interaction between the convection, reaction, and geometry effects and its effect on the flow behavior.

Stimulating Effects of Far-infrared Ray Radiation on the Release of Antioxidative Phenolics in Grape Berries

  • Eom, Seok-Hyun;Park, Hyung-Jae;Seo, Dong-Wan;Kim, Won-Woo;Cho, Dong-Ha
    • Food Science and Biotechnology
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    • v.18 no.2
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    • pp.362-366
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    • 2009
  • This research was conducted to determine the effect of far-infrared ray (FIR) irradiation of grape berries as a potential application for manufacturing grape products with a high amount of antioxidant chemicals. Two grape cultivars, the red grape cv. Campbell Early and the white grape cv. Thompson Seedless, produced increased amounts of crude extracts, in the FIR treatments compared to a non-FIR treatment control with same temperature. However, total phenolic concentrations and antioxidant activity in a 'Campbell Early' increased in the extracts following FIR treatment, whereas those of 'Thompson Seedless' did not increase significantly. High performance liquid chromatography (HPLC) analysis indicated that functional components affecting antioxidant activity were significantly increased in the extract of 'Campbell Early' following FIR treatment. Our results indicate that application of FIR treatment in heat process of grapes increases levels of antioxidative phenolic chemicals and it may help to enhance the availability of antioxidative compounds in various grape food products.

Cytoprotective Effects of Dihydrolipoic Acid and Lipoic Acid on the Oxidative Stress in Cultured Rat Cortical Neurons

  • Kim, Won-Ki
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.4
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    • pp.427-433
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    • 1998
  • In brain hypoxic-ischemia, an excess release of glutamate and a marked production of reactive oxygen species (ROS) occur in neuronal and non-neuronal cells. The present study investigated the effect of the biological antioxidants dihydrolipoic acid (DHLA) and lipoic acid (LA) on N-methyl-D-aspartate (NMDA)- and ROS-induced neurotoxicity in cultured rat cortical neurons. DHLA enhanced NMDA-evoked rises in intracellular calcium concentration ($[Ca^{2+}]_i$). In contrast, LA did not alter the NMDA-evoked calcium responses but decreased after a brief treatment of dithiothreitol (DTT), which possesses a strong reducing potential. Despite the modulation of NMDA receptor-mediated rises in $[Ca^{2+}]_i$, neither DHLA nor LA altered the NMDA receptor-mediated neurotoxicity, as assessed by measuring the amount of lactate dehydrogenase released from dead or injured cells. DHLA, but not LA, prevented the neurotoxicity induced by xanthine/xanthine oxidase-generated superoxide radicals. Both DHLA and LA decreased the glutathione depletion-induced neurotoxicity. The present data may indicate that biological antioxidants DHLA and LA protect neurons from ischemic injuries via scavenging oxygen free radicals rather than modulating the redox modulatory site(s) of NMDA receptor.

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A Study of Contents's Effect on Intercultural Communication (콘텐츠가 문화커뮤니케이션에 미치는 영향)

  • 신정숙
    • Archives of design research
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    • v.11 no.1
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    • pp.33-42
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    • 1998
  • The movie, (Jurassic Park) made by ultramodern Computer Graphics has earned 100 million dollors admission fee in 9 days after opening release and has earned 3000 million dollors that add direct income to relative field income composed by fancy industry, theme park, and so on. If you compare the income with hollywood movies with ours total amount of export, you will know the contents industry scale Many countries weight on contents industry in national supports movies, now. All image softwares that have same target movies, computer game, animation, etc. compress to contents to entertainment and was expected to secure the superiority on the 21th ultramodern media industry. The one have hegemony 21th information period if how much have the contents by the dizital broadcasting. But meaning of intercultural communication play on important part more value of contents than value of political and economical aspect.

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Hepatic Fibrosis Inhibitory Effect of Peptides Isolated from Navicula incerta on TGF-β Induced Activation of LX-2 Human Hepatic Stellate Cells

  • Kang, Kyong-Hwa;Qian, Zhong-Ji;Ryu, BoMi;Karadeniz, Fatih;Kim, Daekyung;Kim, Se-Kwon
    • Preventive Nutrition and Food Science
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    • v.18 no.2
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    • pp.124-132
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    • 2013
  • In this study, novel peptides (NIPP-1, NIPP-2) derived from Navicula incerta (microalgae) protein hydrolysate were explored for their inhibitory effects on collagen release in hepatic fibrosis with the investigation of its underlying mechanism of action. TGF-${\beta}1$ activated fibrosis in LX-2 cells was examined in the presence or absence of purified peptides NIPP-1 and NIPP-2. Besides the mechanisms of liver cell injury, protective effects of NIPP-1 and NIPP-2 were studied to show the protective mechanism against TGF-${\beta}1$ stimulated fibrogenesis. Our results showed that the core protein of NIPP-1 peptide prevented fibril formation of type I collagen, elevated the MMP level and inhibited TIMP production in a dose-dependent manner. The treatment of NIPP-1 and NIPP-2 on TGF-${\beta}1$ induced LX-2 cells alleviated hepatic fibrosis. Moreover, ${\alpha}$-SMA, TIMPs, collagen and PDGF in the NIPP-1 treated groups were significantly decreased. Therefore, it could be suggested that NIPP-1 has potential to be used in anti-fibrosis treatment.

A Case Study of the Effect of the Manual Therapy on Patient with Posttraumatic Stress Disorder, Sleep Disturbance and CLBP (외상후 스트레스 장애를 가진 만성요통 환자에게 도수치료가 외상후 스트레스와 수면 장애 및 통증에 미치는 영향-사례 연구)

  • Yu, Seong-Hun;Kang, Yong-Ju;Kim, Tae-Won
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.20 no.1
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    • pp.47-52
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    • 2014
  • Background: This case study is to describe the manual therapy for the patient with posttraumatic stress (PTSD), sleep disturbance, and pain such as chronic low back pain (CLBP). Methods: The patient who participated in this study was a 60 year-old male PTSD patient with CLBP. His CLBP is not from any genetic or family history but a sequelae of torture that he had gone through about 30 years ago. Prior to the intervention, it was assessed that the PDS-K score was 16, PQSI-K was 12, SLR-90-R was low, VAS score was 10, and KODI socre was 25. The intervention was conducted through manual therapy (myofascial release, muscle energy technique, lumbar stabilization) twice a week for eight weeks in total. Results: After eight week-intervention, the PDS-K, SLR-90-R, VAS, and KODI score were improved whereas PQSI-K was not sufficiently fast improved. Conclusions: The manual therapy is substantially effective in dealing with PTSD and CLBP.

Effects of Thermal Treatment on Structural Properties of DLC Films Deposited by FCVA Method (FCVA 방법으로 증착된 DLC 박막의 열처리에 따른 구조적 물성 분석)

  • 김영도;장석모;박창균;엄현석;박진석
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.52 no.8
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    • pp.325-329
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    • 2003
  • Effects of thermal treatment on the structural properties of diamond-like carbon (DU) films were examined. The DLC films were deposited by using a modified filtered cathodic vacuum arc (FCVA) deposition system and by varying the negative substrate bias voltage, deposition time, and nitrogen flow rate. Thermal treatment on DLC films was performed using a rapid thermal annealing (RTA) process at $600^{\circ}C$ for 2min. Raman spectroscopy, x-ray photoemission spectroscopy (XPS), atomic force microscope (AFM), and surface profiler were used to characterize the I$_{D}$I$_{G}$ intensity ratio, sp$^3$ hybrid carbon fraction, internal stress, and surface roughness. It was found for all the deposited DLC films that the RTA-treatment results in the release of internal compressive stress, while at the same time it leds to the decrease of sp$^3$ fraction and the increase of I$_{D}$I$_{G}$ intensity ratio. It was also suggested that the thermal treatment effect on the structural property of DLC films strongly depends on the diamond-like nature (i.e., sp$^3$ fraction) of as-deposited film.ed film.

Effect of Nitrogen Ion Implantation on Wear Behavior of Biocompatible Ti Implant (질소이온 주입이 생체적합성 티타늄 임플란트의 마모특성에 미치는 영향)

  • Byeon, Eung-Seon;Kim, Dong-Su;Lee, Gu-Hyeon;Jeong, Yong-Su
    • 연구논문집
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    • s.30
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    • pp.137-145
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    • 2000
  • Since the concept of osseointegration was introduced, titanium and titanium-based alloy materials have been increasingly used for bone-anchored metal in oralmaxillofacial and orthopedic reconstruction. Successful osseointegration has been attributed to biocompatibility and surface condition of metal implant among other factors. Although titanium and titanium alloys have an excellent over the metal ion release and biocompatibility, considerable controversy has developed over the metal ion and wear debris in vivo and vitro. In this study, nitrogen ion implantation technique was used to improve the corrosion resistance and wear property of titanium materials, ultimately to enhance the tissue reaction to titanium implants As ion implantation energy was increased, projected range of nitrogen ion the Ti substrate was gradually increased. Under condition of constant ion energy. atomic concentration of nitrogen was also increased with ion doses. The friction in Hank's solution was increased with ion doses. The friction coefficient of ion implanted specimens in HanK's solution was increased from 0.39, 0.47 to 0.52, 0.65 respectively under high energy and ion dose conditions. As increasing ion energies and ion dose, amount of wear was reduced.

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An Analysis of Flow Phenomena in Shock Tube System Design(I)-Comparison of Experimental and Computation Result- (충격파관 장치설계를 위한 유동현상의 해석(1)-계산치와 실험치의 비교-)

  • 정진도;수곡행부
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.5
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    • pp.1218-1226
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    • 1994
  • The shock tube is a useful device for investigating shock phenomena, spray combustion, unsteady gas dynamics, etc. Therefore, it is necessary to analyze exactly the flow phenomena in shock tube. In this study, the mechanics of its reflected shock zone has been investigated by using of the one-dimensional gas dynamic theory in order to estimate the transition from initial reflection of shock wave region. Calulation for four kinds of reflected shock tube temperature (i.e. (a) 1388 K (b) 1276 K (c) 1168 K (d) 1073 K) corresponding to the experimental conditions have been carried out sumarized as follows. (1) The qualitative tendency is almost the same as in that conditions in region of reflected wave region. (2) High temperature period (reflected shock wave temperature) $T_{5}$, exists 0-2.65 ms. (3) Transition period from temperature of reflection shock wave is far longer than the calculated one. This principally attributed to the fact that the contact surface is accelerated, also, due to the release of energy by viscoity effect. This apparatus can advance the ignition process of a spray in a ideal condition that involved neither atomization nor turbulent mixing process, where, using a shock tube, a column of droplets freely from atomizer was ignited behind a reflected shock.