• Title/Summary/Keyword: T.K.E.

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Effect of Transition Metal on the Thermal Stability and Mechanical Property of Fe-based Amorphous Alloys (Fe기 비정질합금의 열적안정성 및 기계적 성질에 미치는 천이금속의 영향)

  • Gook, Jin Seon;Yoon, Dong Joo
    • Journal of the Korean Society for Heat Treatment
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    • v.14 no.6
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    • pp.345-349
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    • 2001
  • This study has investigated the effect of thermal stability and mechanical property of $Fe_{80-X}P_{10}C_6B_4M_X$(X=2, 4, 6, M=transition metal) amorphous alloys fabricated by the melt-spun process. The glass transition temperature($T_g$), crystallization temperature($T_x$) and hardness increase with decreasing electron concentration (e/a) from about 7.38 to 7.18. The decrease of e/a implies the increase in the attractive bonding state between the M elements and other constituent element. The decrease in a/e leads to the enhancement of the attractive bonding state among the constituent elements which is favorable for the increase in $T_g$, $T_x$ and hardness.

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Effects of Six Different Starter Cultures on Mutagenicity and Biogenic Amine Concentrations in Fermented Sausages Treated with Vitamins C and E

  • Kim, Hyeong Sang;Lee, Seung Yun;Kang, Hea Jin;Joo, Seon-Tea;Hur, Sun Jin
    • Food Science of Animal Resources
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    • v.39 no.6
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    • pp.877-887
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    • 2019
  • This study was performed to determine changes in mutagenicity and biogenic amine concentrations in sausages fermented with six different starter cultures treated with vitamins C and E. Six different types of fermented sausages with different combination of starter cultures were manufactured. T1, Pediococcus acidilactici; T2, P. pentosaceus and Staphylococcus carnosus; T3, S. carnosus, S. xylosus, Debaryomyces hansenii, Lactobacillus curvatus, and P. pentosaceus; T4, S. carnosus and L. sakei; T5, S. xylosus and L. plantarum; and T6, Penicillium nalgiovensis. After treatment with vitamins C and E in fermented sausages, changes in mutagenicity and biogenic amine concentrations were measured. The sausages fermented with Staphylococcus xylosus and Lactobacillus plantarum starter cultures showed the most effective antimutagenic activity (p<0.05). The mutagenicity was further decreased in the sausages treated with vitamins C and E (p<0.05), regardless of the starter cultures. The use of Pediococcus acidilactici, S. xylosus, L. plantarum, and Penicillium nalgiovensis as starter cultures was effective in decreasing biogenic amine concentrations (p<0.05). In addition, vitamin E was more effective in decreasing the biogenic amine concentrations than vitamin C. In conclusion, we recommend the use of S. xylosus and L. plantarum as starter cultures, in addition to the use of vitamins C and E, to reduce the potential risk of meat mutagens in fermented sausages.

Changes of IgE production, splenic helper and suppressor T lymphocytes in mice infected with Paragonimus westermani (폐흡충(Paragonimus westermani) 감염이 흰쥐의 IgE 생성 및 비장림프구 아군분포에 미치는 영향)

  • Min, Deuk-Yeong;Ryu, Jae-Suk;Sin, Myeong-Heon
    • Parasites, Hosts and Diseases
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    • v.31 no.3
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    • pp.231-238
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    • 1993
  • Effects of Paragonims westermai infection were observed in mice on the change of serum IgE level, the number of peripheral eosinophils and the distribution of Thy $1.2^{+}{\;}(CD3),{\;}L3T4^{+}{\;}(CD4),{\;}and{\;}Lyt-2^{+}$ (CD8) splenic T Iymphocytes without mitogen serum IgE increased at 3 weeks after the infection and reached a peak on week 4 and maintained high levels of IgE until the 23r6 week. Peripheral eosinophil numbers Increased at the second week and attained peak level on week 9. The frequency of $L3T4^{+}$(CD4) and $Lyt-2^{+}$ (CD8) T Iymphocytes decreased slightly until 4 weeks after the infection, but not significantly. Absolute number of $L3T4^{+}{\;}and{\;}Lyt-2^{+}$ T Iymphocytes, and the ratio of L3T4/Lyt-2 were not markedly changed over the period of observation. The frequency of Thy $1.2^{+}$ (CD3) T lymphocytes in the infected group slightly decreased until 4 weeks after the infection and showed significant reductions at the 2nd and 4th week of the infection (p < 0.05).

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Effects of Minor Arginyl tRNA and Isoleucyl tRNA on the Expression of Clostridium botulinum Neurotoxin Light Chain in Escherichia coli

  • Kim, Jin-Sook;Seong, Hye-Young;Kim, Mi-Wha;Ku, Jong-Seo;Choi, Soon-Yong
    • Journal of Microbiology and Biotechnology
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    • v.13 no.2
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    • pp.287-291
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    • 2003
  • Botulinum neurotoxin type A (BONT/A) is an extremely potent toxin, which is produced by Clostridium botulinum. The light chain of this protein (BONT/A LC), which is known as a zinc endopeptidase, cleaves SNAP-25 involved in the exocytosis process. In this work, the expression of recombinant BoNT/A LC in E. coli is described. The BONT/A LC gene of C. botulinum contains a high frequency of the arginine AGA and isoleucine ATA codons that are rarely used in genes of E. coli, hampering the translation of recombinant protein. The argD and ilex tRNA genes were cloned into pACYC184 vector, resulting in pAAD131X plasmid. The translational stress of the toxin gene related to codon bias was reversed by fupplernentation of the AGA arginyl tRNA of T4 phage and AUA isoleucyl tRNA of E. coli. This system may be applicable for the expression of a variety of AT-rich heterologous genes in E. coli.

A NOTE ON THE ESSENTIAL SPECTRUM OF AN IRREDUCIBLE P-HYPONORMAL OPERATOR

  • Lee, Kwang-Il;Cha, Hyung-Koo
    • East Asian mathematical journal
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    • v.17 no.1
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    • pp.87-92
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    • 2001
  • In this paper, we have the extended result of Bunce's theorem. And we show that if T is an irreducible p-hyponormal operator such that T*T-TT* is compact, then ${\sigma}_{ap}(T)={\sigma}_e(T)$ and ${\sigma}_p({\phi}(T))={\sigma}_e({\phi}(T))$.

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Nitric Oxide-Induced Autophagy in MC3T3-E1 Cells is Associated with Cytoprotection via AMPK Activation

  • Yang, Jung Yoon;Park, Min Young;Park, Sam Young;Yoo, Hong Il;Kim, Min Seok;Kim, Jae Hyung;Kim, Won Jae;Jung, Ji Yeon
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.6
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    • pp.507-514
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    • 2015
  • Nitric oxide (NO) is important in the regulation of bone remodeling, whereas high concentration of NO promotes cell death of osteoblast. However, it is not clear yet whether NO-induced autophagy is implicated in cell death or survival of osteoblast. The present study is aimed to examine the role of NO-induced autophagy in the MC3T3-E1 cells and their underlying molecular mechanism. The effect of sodium nitroprusside (SNP), an NO donor, on the cytotoxicity of the MC3T3-E1 cells was determined by MTT assay and expression of apoptosis or autophagy associated molecules was evaluated by western blot analysis. The morphological observation of autophagy and apoptosis by acridine orange stain and TUNEL assay were performed, respectively. Treatment of SNP decreased the cell viability of the MC3T3-E1 cells in dose- and time-dependent manner. SNP increased expression levels of p62, ATG7, Beclin-1 and LC3-II, as typical autophagic markers and augmented acidic autophagolysosomal vacuoles, detected by acridine orange staining. However, pretreatment with 3-methyladenine (3MA), the specific inhibitor for autophagy, decreased cell viability, whereas increased the cleavage of PARP and caspase-3 in the SNP-treated MC3T3-E1 cells. AMP-activated protein kinase (AMPK), a major autophagy regulatory kinase, was activated in SNP-treated MC3T3-E1 cells. In addition, pretreatment with compound C, an inhibitor of AMPK, decreased cell viability, whereas increased the number of apoptotic cells, cleaved PARP and caspase-3 levels compared to those of SNP-treated MC3T3-E1 cells. Taken together, it is speculated that NO-induced autophagy functions as a survival mechanism via AMPK activation against apoptosis in the MC3T3-E1 cells.

An analysis of the Reacture Inutuation of falling type Impact Test for toughened Rigid Plastics (인성의 강소성 플라스틱 재료에 대한 낙하충격 시험의 파괴개시에 관한 연구)

  • 김진우
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.8 no.4
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    • pp.385-393
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    • 1984
  • 본 연구에서는 다트식 낙하충격 시험에 있어서 인성의 강소성 플라스틱 재료 의 준정적 선형의 점탄성 모델이 구성되어 해석되었다. 완화계수함수, E(t)=E$_{f}$ +(E$_{o}$ -E$_{f}$ )e$^{-t/tR}$ 형태의 점탄성 재료의 수정된 Maxwell요소모델을 근거 로 충격속도, 파괴에너지, 임계응력등의 중요변수들의 상대적 종속성이 근사계산으로 평가되었다.

Effect of Water Quality of Artificial Sewage on E. coli Disinfection Using Electrolysis Process (전기분해 공정을 이용한 E. coli 소독에 미치는 인공하수 수질의 영향)

  • Park, Young-Seek;Kim, Dong-Seog
    • Journal of Environmental Science International
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    • v.20 no.9
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    • pp.1115-1124
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    • 2011
  • There is an increasing incidence in health problems related to environmental issues that originate from inadequate treatment of sewage. This has compelled scientists to engage in innovative technologies to achieve a effective disinfection process. Electrolysis has emerged as one of the more feasible alternatives to conventional disinfection process. The objectives of the present paper were to investigate the effect of chemical characteristics on oxidant formation and Escherichia coli (E. coli) disinfection in synthetic sewage effluents. The influence of parameters such as COD, SS, T-N and T-P were investigated using laboratory scale batch reactor. The results showed that the higher COD, T-N and T-P concentration, the lower N, N-Dimethyl-4-nitrosoaniline (RNO, indicator of the generation of OH radical) degradation and E. coli disinfection was observed. The order of effect of RNO degradation and E. coli disinfection was T-P > COD > T-N > SS. When 4 parameter of water quality were worked simultaneously, oxidants formation and disinfection was decreased with increase of the concentration of sewage. To increase of the disinfection performance, the increase of disinfection time or electric power was need.

Variation of Inclusion Selectivities of the Cadmium Host Complexes with Ammonium Oniums for Aromatic Guest Molecules (암모니움 이온을 가진 카드뮴 호스트 착물의 방향족 게스트 분자에 대한 포접선택성 변화)

  • Kim, Chong-Hyeak;Lee, Sueg-Geun
    • Analytical Science and Technology
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    • v.17 no.3
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    • pp.282-288
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    • 2004
  • Inclusion selectivities of the cyanocadmate host complexes with ammonium oniums, $[Cd_x(CN)_{2x}][onium{\cdot}zG]$ (onium = $NMe_3Et^+$, $NMeEt{_3}^+$ and $NEt{_4}^+$, G = guest), have been investigated for $C_6H_6$ (B), PhMe (T), PhEt (E), ortho (O), meta (M), and para (P) isomers of $C_6H_4Me_2$ as the aromatic guest molecules. From the binary, ternary, quaternary and quinary mixed guests of B, T, E, O, M and P, the order of preference in the $NMe_3Et+$-host is $B{\gg}$T>P${\fallingdotseq}O{\fallingdotseq}M$ and E>O${\gg}P{\fallingdotseq}M$; in the $NMeEt{_3}^+$-host is T>B>P${\gg}O{\fallingdotseq}M$ and E>P${\gg}$M>O; in the $NEt{_4}^+$-host is $B{\gg}T{\fallingdotseq}O{\fallingdotseq}M{\fallingdotseq}P$. However, the $NEt{_4}^+$-host complexes of E, O, M and P mixed-guests were not obtained. These inclusion selectivities were compared to our previous results of the $NMe{_4}^+$-host; T>B>P${\gg}$M>O and E>P${\gg}$M>O.

Applicability Evaluation after Treated with Consolidant of 0.8T0.2E1G_3wt0.08% and 1T1G_7wt0.08% on Marble Surface (강화제 0.8T0.2E1G_3wt0.08%와 1T1G_7wt0.08%의 대리암에 대한 적용성 평가)

  • Do, Jin Young;Kim, Jeong Jin
    • Journal of the Mineralogical Society of Korea
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    • v.30 no.4
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    • pp.187-194
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    • 2017
  • In this study, marble that consist mainly of calcite were used for applicability evaluation after treated with consolidant such as alkoxysilane series of 0.8T0.2E1G_3wt0.08% and 1T1G_7wt0.08%. The position and intensity of X-ray diffraction peaks are no change and increasing trend after treated with two consolidants. The results of scanning electron microscopic analysis, morphology of rope type and homogeneous surface of platy or leaflike form observed on the marble after treated with 0.8T0.2E1G_3wt0.08% and 1T1G_7wt0.08%, respectively. Brightness of surface after treated with consolidant are changing slightly dark. Shore hardness and ultrasonic velocity values show increasing after treated on the marble surface with two consolidants.