• Title/Summary/Keyword: reverse fraction

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SFRHPC interior beam-column-slab joints under reverse cyclic loading

  • Ganesan, N.;Nidhi, M.;Indira, P.V.
    • Advances in concrete construction
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    • v.3 no.3
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    • pp.237-250
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    • 2015
  • Beam-column joints are highly vulnerable locations which are to be designed for high ductility in order to take care of unexpected lateral forces such as wind and earthquake. Previous investigations reveal that the addition of steel fibres to concrete improves its ductility significantly. Also, due to presence of slab the strength and ductility of the beam increases considerably and ignoring the effect of slab can lead to underestimation of beam capacity and defiance of strong column weak beam concept. The influence of addition of steel fibres on the strength and behaviour of steel fibre reinforced high performance concrete (SFRHPC) interior beam-column-slab joints was investigated experimentally. The specimens were subjected to reverse cyclic loading. The variable considered was the volume fraction of crimped steel fibres i.e., 0%, 0.5% and 1.0%. The results show that the addition of steel fibres improves the first crack load, strength, ductility, energy absorption capacity and initial stiffness of the beam.

The Effect of Harder Second Phase on Mechanical Properties of Compacted/Vermicular Graphite Cast Iron (CV 흑연주철의 기계적 성질에 미치는 경질의 제2상의 영향)

  • Park, Yoon-Woo
    • Journal of Korea Foundry Society
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    • v.19 no.1
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    • pp.84-90
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    • 1999
  • In this study, CV cast iron was reverse transformed to produce harder second phase surrounding graphite nodules, and then the microstructure and related mechanical properties of the reverse transformed CV cast iron were investigated by using optical microscopy and by carrying out hardness, tension and impact test. The formation of hard second phase surrounding graphite nodules increased the hardness in CV cast iron. The marked increase in hardness was resulted from the formation of martensite surrounding graphite nodule. It is expected from these results that the formation of martensite surrounding graphite nodule would improve the wear resistance of CV cast iron. The formation of both martensite and pearlite surrounding graphite nodule improved the tensile properties. Impact properties were decreased with increasing the volume fraction of hard second phase. However, the reduced impact properties could be recovered through phase transformation of martensite into pearlite and sorbite by tempering.

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Purification and Partial Amino Acid Sequence of a Bacteriocin Produced by Lactococcus, sp. HY449 (Lactococcus sp. HY449가 생산한 Bacterisocin의 정제)

  • 오세종;이상준;김경태;김상교;박연희;백영진
    • Microbiology and Biotechnology Letters
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    • v.29 no.3
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    • pp.155-161
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    • 2001
  • A bactriocin produced by Lactrococcus sp. HY449 was purified by sequential purfication steps such as n-propanol-acetone precipitation ion -exchange chromatography using CM-Sequential CL6B. gel filtration chromatography using Sephacry HR100 and reverse-phase chromatography using pro RPC HR 5/10. Reverse-phase chromatography the final step of the purfication yielded a single symmetrical peak of bacteriocin activity The purification resulted in final yield of 3.25% and 413.35 fold increase of the specific activity of bacteriocin. The active fraction from reverse-phase chromatography was used for N-terminal amino acid analysis . The purified bacteriocin contained isoleucine, leucine, methionine, and glycine at but N-terminal end no aromatic amino acids. Calculation of the number of amino acid residues in the bacteriocin revealed that it is consisted of 32 residues assuming the molecular weight of bacteriocin to be about 3.6kDa. Edman degrandation elucidated amino acid residues of the first four of the N-terminus to be $NH_2$-Ile-Leu-Pro-GIn.

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Effects of Butanol extract from Rhois Vernicifluae Cortex (RVC) in lipopolysaccharides-induced macrophage RAW 264.7 cells (칠피(漆皮) 부탄올 분획물이 LPS로 유도된 RAW 264.7 대식세포에 미치는 영향)

  • Song, Saeng-Yeop;Sim, Sung-Yong;Kim, Kyung-Jun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.20 no.1 s.32
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    • pp.1-15
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    • 2007
  • Objectives : RVC has long been used for a useful natural agent ameliorating inflammation related symptoms in the folk medicine recipe. This study was performed to investigate effects of RVC on the inflammation and oxidation in RAW 264.7 cells. Methods : The RVC was extracted with 80% ethanol and sequentially partitioned with solvents in order to increase polarity. With the various fractions, we determined the activities on the inflammation and oxidation in RAW 264.7 cells. Results : 1. Among the various solvent extracts of RVC, the butanol fraction showed the most powerful inhibitory ability against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells without affecting cell viability. 2. Butanol fraction showed a oxidation inhibition effect by decreasing the DPPH and OH radicals. 3. Butanol fraction exhibited the inhibitory avilities against iNOS and COX-2. 4. Reverse transcriptase polymerase chain reaction (RT-PCR) and Westem blotting analysis revealed that the BuOH fraction provided a primary inhibitor of the iNOS protein and mRNA expression in LPS-induced RAW 264.7 cells. Among the up-regulater molecules of iNOS and COX-2, the BuOh fraction of RVC was shown the inhibitory activity of phoshporylation of c-Jun N-terminal kinase (JNK) 1/2 and threonine protein kinase (AKT), the one of the MAPKs pathway. Conclusion : Thus, the present study suggests that the response of a component of the BuOH fraction to NO generation via iNOS expression provide a important clue to elucidate anti-inflammatory and anti-oxidation mechanism of RVC.

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Effect of Heat Treatment Temperature on Amount of Stress-Induced ${\varepsilon}$ Martensite in an Fe-Mn Baesd Alloy (Fe-Mn계 합금에서 응력유기 ${\varepsilon}$ 마르텐사이트의 양에 미치는 열처리 온도의 영향)

  • Jee, K.K.;Han, J.H.;Jang, W.Y.
    • Journal of the Korean Society for Heat Treatment
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    • v.17 no.6
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    • pp.342-345
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    • 2004
  • In this work, a new method of measuring volume fraction of deformation-induced ${\varepsilon}$ martensite is proposed using endothermic heat on reverse transformation. As grain size increases, the amount of ${\varepsilon}$ martensite forming on cooling increases. However, with a decrease in grain size, more ${\varepsilon}$ is induced by deformation, improving shape memory effect.

Detection of Phagocytosis-Promoting Factor of Culture Supernatant from Feline Peripheral Blood Mononuclear Cells Cultured with Egg White Derivatives (계난백유래물질로 배양한 고양이 말초혈액 단핵구세포 배양상층액중의 탐식촉진인자 검출)

  • 양만표;김기홍
    • Journal of Veterinary Clinics
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    • v.16 no.1
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    • pp.31-36
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    • 1999
  • The aim of this study is to determine the phagocytosis-promoting factor(s) for feline peripheral blood polymorphonuclear cells (PMN) by culture supernatant from mono-nuclear cells (MNC) treated with egg white derivatives (EWD). The phagocytic activity of PMN was analyzed by a flow cytometry system. The EWD did not show direct effect on the phagocytic response of PMN. The phagocytic activity of PMN was enhanced by culture supernatant from MNC but not PMN treated with EWD. Therefore, it was suggested that the enhanced phagocytic activity of feline PMN could be mediated by humoral factor(s) released from MNC treated with EWD. Thus, the phagocytosis-promoting factor(s) in supernatant fraction from MNC culture treated with EWD were isolated by reverse phase high pressure liquid chromatography. The resulting supernatant fraction on 29.02 minutes of retention time showed high phagocytic activity of PMN. The molecular weight of this supernatant fraction was 16 to 18 kDa when analyzed by capillary electrophoresis. The isoelectric point was pH 5.76 when assessed by ion-exchange chromatography. These results suggest that EWD stimulates feline MNC to elaborate a phagocytosis-promoting factor, 16 to 18 kDa of molecular weight, which could be an important mediator for the enhancement of phagocytic activity of feline peripheral blood phagocytes. Further study will be needed to elucidate this phagocytic factor.

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Leaves of Raphanus sativus L. Shows Anti-Inflammatory Activity in LPS-Stimulated Macrophages via Suppression of COX-2 and iNOS Expression.

  • Park, Hye-Jin;Song, Minjung
    • Preventive Nutrition and Food Science
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    • v.22 no.1
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    • pp.50-55
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    • 2017
  • Raphanus sativus L. (RS) is a cruciferous vegetable that is widely consumed in Korea. The anticancer activity of leaves of RS (RSL) extract has been investigated; however, no studies focused on its anti-inflammatory effects. Therefore, the aim of the current study was to evaluate the anti-inflammatory effects of RSL extract. In brief, RSL powder was fractionated into n-hexane, chloroform, ethyl acetate, n-butanol, and water-soluble fractions. Lipopolysaccharide (LPS)-stimulated RAW264.7 cells were treated with each fraction for initial screening. It was found that the chloroform fraction significantly inhibited nitric oxide release in LPS-stimulated RAW264.7 cells with a half maximal inhibitory concentration value of $196{\mu}g/mL$. In addition, the mRNA and protein expression levels of inducible nitric oxide synthase, measured using reverse transcriptase-polymerase chain reaction and western blotting, respectively, were reduced in a concentration-dependent manner. Moreover, the inflammatory cyclooxygenase-2 enzyme expression decreased. Furthermore, the expression of nuclear factor-kappa B ($NF-{\kappa}B$), the key regulator of the transcriptional activation of the inflammatory cytokine genes, was reduced by the RSL chloroform fraction. Therefore, the results of our study suggest that RSL exhibits anti-inflammatory effects in LPS-stimulated macrophages via $NF-{\kappa}B$ inactivation.

Antiinflammatory and antioxidative effects of Agrimonia pilosa Ledeb

  • Sim, SY;Kim, GJ;Ko, SG
    • Advances in Traditional Medicine
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    • v.7 no.3
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    • pp.217-228
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    • 2007
  • Agrimonia pilosa Ledeb. has long been used for a useful natural agent ameliorating inflammation related symptoms in the folk medicine recipe. This study was performed to investigate effects of Agrimonia pilosa Ledeb.(AP) on the expression of inflammation related genes such as the inducible nitric oxide synthase (iNOS) in macrophage cell line, RAW 264.7 cells. The AP (whole plants) was extracted with 80% ethanol and sequentially partitioned with solvents in order to increase polarity. Among the various solvent extracts of AP, the n-butanol (BuOH) fraction showed the most powerful inhibitory ability against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells without affecting cell viability. Reverse transcriptase-polymerase chain reaction and Western blot analysis revealed that the BuOH fraction provided a primary inhibitor of the iNOS protein and mRNA expression in LPS-induced RAW 264.7 cells. The DPPH and OH radical scavenging activities of the several fractions of 80% ethanol extracts of AP significantly increased by EtOAC and BuOH fractions. Thus, the present study suggests that the response of a component of the BuOH fraction to NO generation via iNOS expression provide an important clue to elucidate anti-inflammatory mechanism of AP.

Separation of X-and Y-Bearing Spermatozoa IV. Separtion of bull spermatozoa by the combination of density Gradient Centrifugation and Sephadex Gel filtration (X-정자와 Y-정자의 분류에 관한 연구 IV. Sephadex Gel여과법과 Percoll중층원심분류법의 병용에 의한 우 정자의 분류)

  • 이주영;정길생;김종배
    • Korean Journal of Animal Reproduction
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    • v.12 no.3
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    • pp.141-147
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    • 1988
  • These experiments were carried out to develop new techniques for in vitro separation of x-and Y-bearing spermatozoa. The results obtained in these experiments were summarized as follows: 1. Following centrifugation of discontinuous percoll density gradient, populatin of spermatozoa increased progressively from low to high density. The highest concentration of spermatozoa was observed at the 4th fraction which included 36.6% of spermatozoa. 2. As increasing percoll concentration, the higher motility index was obtained and the highest motility index(74.2) was obtained at the 5th fraction. 3. The percentage of B-body bearing spermatozoa following percoll density gradient centrifugation was decreased from 39.7% to 25.6%. 4. The sperm population following chromatography by sephadex gel and percoll density gradient centrifugation was decreased in 1st, 5th and 6th fractions but the reverse was turn for 2nd, 3rd and 7th fractions, and the highest sperm concentration was observed at the 7th fraction which included 37.4% of spermatozoa. 5. Motility index of spermatozoa was increased from 77.6 to 79.4 after the sephadex gel filtration, however it was decreased at all fractions after percoll density gradient centrifugation. The lowest motility index(33.2) was obtained from the 7th fraction. 6. The rate of B-body bearing spermatozoa was shown the trend to decrease by the sephadex gel filtration and the trend was accelerated by the percoll density gradient centrifugation. The lowest percentage of B-body bearing spermatozoa, 12.0% was obtained from the 5th fraction.

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Bacterial Reverse Mutation Test of Clean Natural using Salmonella typhimurium (천연소독제 Clean Natural의 Salmonella typhimurium에 대한 복귀돌연변이시험)

  • Chun Myung-Sun;Han Sang-Wook;Cho Yoon-Hee;Lim Yeong-Yun;Kim Eui-Gyung;Lee Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.20 no.3
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    • pp.175-178
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    • 2005
  • Clean Natural is a new disinfectant of which main components are propolis and wood vinegar from Quercus mongolica. To evauate the bacterial reverse mutation of Clean Watural, the in vitro Ames test using Salmonella typhimurium TA98, TA100, TA102, TA1535 and TA1537 were performed with clean natural at the concentrations 0, 5, 2.5, and 1.25 mg/ml/plate. Clean Natural was negative in Ames test with Salmonella typhymuyium with and without rat liver microsomal enzyme (S-9 fraction). These results indicate that Clean Watural does not cause bacterial reverse mutation.