• Title/Summary/Keyword: $\alpha-Tip$

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Carcinogenic Role of Tumor Necrosis Factor-α Inducing Protein of Helicobacter pylori in Human Stomach

  • Suganuma, Masami;Kuzuhara, Takashi;Yamaguchi, Kensei;Fujiki, Hirota
    • BMB Reports
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    • v.39 no.1
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    • pp.1-8
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    • 2006
  • Helicobacter pylori is the definitive carcinogen for stomach cancer and is known to induce proinflammatory cytokines, such as tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and interleukin-1(IL-1) in the stomach. Based on our findings that TNF-$\alpha$ is an endogenous tumor promoter, we identified the TNF-$\alpha$ inducing protein (Tip$\alpha$) gene family, and confirmed Tip$\alpha$ and HP-MP1 as new carcinogenic proteins of H. pylori. Tip$\alpha$ protein is unique to H. pylori, and this paper shows the strong tumor promoting activity of Tip$\alpha$ gene family, in cooperation with Ras protein and its mechanisms of action in relation to NF-${\kappa}B$ activation, and discusses the carcinogenic role of Tip$\alpha$ in stomach cancer. Our recent finding showing that penicillin-binding proteins of other bacteria are weak homologues of Tip$\alpha$ is also discussed.

A Study on Photoelastic Fringe Patterns in Cutting Proces(I) (切削加工 의 光彈性的 現象 에 관한 硏究( I ))

  • 김정두;이용성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.7 no.2
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    • pp.161-167
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    • 1983
  • In this study the phenomenon of cutting stress which arises on cutting tools and work pieces in cutting process is investigated by rake angle of cutting tools and feed for this measurement, P$_{s}$-1 (high modulus, photolastic Inc.) was used as a cutting tool, P$_{s}$-3 (medium modulus, photolastic Inc.) was used as work piece and reduction apparatus was attached to the head stock, and orthogonal cutting was adapted as a cutting method and transparent glass was used to block the strain in the orientation of thickness. The followings are the results of this study. (1) Photoelastic experimental equipments have made it possible to make dynamic measurement and analyze stress distribution in cutting tool and work piece surface which has hitherto been conducted only in static measurement and analyzing method. (2) The maximum stress arising at tools and work pieces in cutting process is on the tool edge tip, and the maximum stress arising on the tip of cutting tools is equal to that on the contacting area of work pieces in values. (3) The distributions of maximum shear stress on certain parts of the cutting tools and work pieces are as follows; for cutting tools, .alpha.=12.deg., .alpha.=0.deg., .alpha.=-12.deg. in order, and for work pieces, .alpha.=-12.deg., .alpha.=0.deg., .alpha.=12.deg. in opposite order.der.

유한요소법에 의한 공구인선의 응력분포에 관한 연구

  • Kim, Jeong-Du
    • Journal of the Korean Society for Precision Engineering
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    • v.1 no.1
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    • pp.50-58
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    • 1984
  • In the present paper are calculated and compared the stresses on the normal tools and the restricted tools which have three various rake angles by Least Square Method. The results obtained are summerized as follows. The tool displacement at rake angle .alpha. = 12 .deg. and .alpha. = 0 .deg. is positive value in the principal cutting direction and negative value in the feed direction. At rake angle .alpha. = -12 .deg. the displacement is negative value in both of directions. The principal stress of the restricted and normal tool is maximum at the tip of the tool, the shear stress is maximum after a certain distance from the tip. The result of FEM and P.E method shows that in the range of rapid decreasing of normal stress of the tool edge, the shear stress is maintaining a certain value. This is due to the friction characteristic of the chip.

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Influence of Anisotropic Property Ratio of Orthotropic Material on Stress Components and Displacement Components at Crack tip Propagating with Constant Velocity Under Dynamic Mode I (동적모드 I 상태에서 직교 이방성체의 이방성비가 등속전파 균열선단의 응력성분과 변위성분에 미치는 영향)

  • 이광호;황재석;최선호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.1
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    • pp.87-98
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    • 1995
  • When the crack in orthotropic material is propagating under dynamic model I load, influences of anisotropic property ratio $E_{L}$/ $E_{T}$ on stress and displacement around propagating crack tip are studied in this paper. When M<0.55 and .alpha.=90.deg.(.alpha.; the angle of fiber direction with crack propagating direction, M; crack propagation velocity/shear stress wave velocity), the influence of $E_{L}$/ $E_{T}$ on stress .sigma.$_{x}$, .sigma.$_{y}$, .tau.$_{xy}$ and .sigma.$_{\theta}$ is the greast on .sigma.$_{y}$. Except M<0.55 and .alpha.=90.deg., it is the greast on .sigma.$_{x}$ in any situation. Increasing $E_{L}$/ $E_{T}$, stress components are increased or decreased. When maximum stress is based, the stress .sigma.$_{x}$(.alpha.=90.deg.), .sigma.$_{y}$(.alpha.=0.deg.) and .tau.$_{xy}$ (.alpha.=90.deg.) are decreased with increment of $E_{L}$/ $E_{T}$ in M=0. any stresses except .sigma.$_{*}$x/(.alpha.=0.deg.) are decreased with increment of $E_{L}$/ $E_{T}$ in M=0.9. When .alpha.=90.deg., the influence of $E_{L}$/ $E_{T}$ on displacement U and V is V>U in any velocities of crack propagation, when .alpha.=0.deg., it is VU in M>0.75 and when $E_{L}$/ $E_{T}$ is increased, U and V are decreased in any conditions.sed in any conditions.tions.tions.tions.

Photoswitching Characteristics of Biodevice Consisting of Chlorophyll $\alpha$ Langmuir-Blodgett Film

  • Nam, Yun-Suk;Choi, Jeong-Woo;Lee, Won-Hong
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.1038-1042
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    • 2004
  • The photoelectric responses of a biodevice consisting of chlorophyll $\alpha$ Langmuir-Blodgett film were investigated. Chlorophyll $\alpha$ Langmuir-Blodgett films were deposited onto ITO and Au coated glass. To confirm film formation, surface analysis of chlorophyll $\alpha$ Langmuir-Blodgett film was carried out by measurement using atomic force microscopy. The metal/insulator/metal structured biodevice was constructed by depositing aluminum onto the chlorophyll $\alpha$ Langmuir-Blodgett film surface. To investigate the photoelectric response, the current-voltage characteristic was measured by the conducting metal tip. The photoswitching function and transient photovoltage characteristics of the proposed device were measured by irradiation with Ar ion laser and $N_2$ pulse laser, respectively. This research suggested that the proposed biodevice consisting of chlorophyll $\alpha$ could be applied to the molecular scale biosensor and/or bioelectronic device.

Immunocytochemical Investigation on the Intracisternal Accumulations of Storage Protein in Pea Cotyledon Cells (완두 자엽세포의 소포체 내강에 축적된 저장 단백질에 대한 면역세포화학적 연구)

  • Jeong, Byung-Kap;Park, Hong-Duok
    • Applied Microscopy
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    • v.31 no.2
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    • pp.199-206
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    • 2001
  • In 1980s, the fragmentation or subdivision of protein deposits at the periphery of protein storage vacuole was suggested as the only route of PB development in pea cotyledon cells. Since then, other independant processes such as terminal dilation , transformation and de novo development have been discussed as alternative routes for PB development, and today, these multiple mechanisms of PB development are accepted as a result of active investigations. For analysis of the protein accumulations in the ER cisternae during seed development, immunocytochemical gold labellings were applyed on the single cells separated by enzymatic digestion from cotyledon tissue. Anti-legumin labellings at the early stage, and anti-vicilin labellings at the intermediate stage were observed on the protein-filled ER. The $\alpha-Tip$, which is the ER retention protein, was labelled somewhat at late stage, and PPase, a sort of tonoplast membrane protein, was labelled at early stage.

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An Efficient In vitro Propagation of Zanthoxylum piperitum DC.

  • Hwang, Sung-Jin;Hwang, Baik
    • Korean Journal of Medicinal Crop Science
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    • v.11 no.4
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    • pp.316-320
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    • 2003
  • A protocol is described for rapid multiplication of Zanthoxylum piperitum DC. (Rutaceae), an important aromatic and medicinal plant, through shoot-tip explant cultures. Murashige and Skoog (MS) medium supplemented with various concentrations of N-6-benzyladenine (BA), N-6-benzylaminopurine (BAP) and thidiazuron (TDZ), in single or in combination with ${\alpha}-naphthaleneacetic$ acid (NAA), was used to determine the rate of shoot proliferation. N-6-benzyladenine (BA) used at 0.5mg/l, was the most effective in initiating multiple shoot proliferation at the rate of 23 microshoots per shoot-tip explants after 40 days of culture. Shoot multiplication increased 1.2-fold in each successive subculture. Induction of rooting (98%) was achieved by transferring the shoots to the same basal medium containing 2 mg/l indole-3-butyric acid (IBA). Plantlets went through a hardening phase in a controlled growth chamber, prior to in vivo transfer. These results represented that possible application for the mass production of plantlets through in vitro culture system of Zanthoxylum piperitum DC.

A Study on Photoelastic Fringe Patterns in Cutting Process(II) (切削加工 의 光彈性的 現象 에 관한 硏究 (II))

  • 김정두;이용성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.8 no.5
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    • pp.401-407
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    • 1984
  • In the previous paper, part I, the principal stresses were investigated on the normal tools and the workpieces whose materials were the same epoxy resin. In this paper, are measured and compared the stresses on the normal tools and restricted tools which have three various rake angles. Each restricted tool above has the same restricted angle. The workpieces used in this experiment are made of high quality lead. The photoelastic measuring device is attached to the saddle of the lathe and carried at the same speed as the cutting tool is feeded. The results obtained are summarized as follows; The shear stresses on the tip of the restricted tools of the rake angle .alpha.=12.deg. and .alpha.=0.deg. are less than those of normal tools. But, for the rake angle .alpha.=-12.deg., the former is greater than the latter. The result of photoelastic method shows that in the range of rapid decreasing of normal stress on the tool edge, the shear is maintaining a certain value.

Floor Field Behind an Axial Compressor Rotor ( I );Locus of Tip Leakage Vortex (축류압축기 회전익의 후방유동장(I) - 누설와류의 궤적)

  • 조강래;정의준
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.3
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    • pp.963-969
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    • 1991
  • 본 연구에서는 누설와류는 유동에 영향을 미치며 에너지 손실로 된다. 누설 와류에 의한 손실은 다른 원인에 의한 손실에 비교하여 그 비중이 크다. 따라서 누 설와류 특성을 이해하기 위해 설계영각(.alpha.=10.7˚)에서 절현비를 t/C=0.90와 2.71로 바꾸고, 또 절현비가 설계절현비 t/C=0.90일 경우에 영각을 설계 영각 .alpha.=10.7˚와 실 속점의 영각 .alpha.=18.9˚사이에서 바꾸어 회전익 후방의 회전유동장을 측정하여 누설와 류의 거동을 연구하였다.

Characteristics of Fatigue Crack Propagation and Changes in Strain Induced Martensite α' of STS 304 Stainless Steel (LNG 304 스테인레스강의 피로균열전파특성과 변형유발 마르텐사이트 함량의 변화)

  • Kim, Song-Hee;Pak, Hyung-Rae;Lee, Hyun-Seung
    • Journal of Industrial Technology
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    • v.21 no.B
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    • pp.341-348
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    • 2001
  • The effect of initial ${\alpha}^{\prime}$ in STS 304 Stainless Steel on fatigue resistance, and fatigue crack propagation behavior was studied with using C-T specimens. Higher ${\Delta}K_{th}$ was observed in the specimens with the content of 0% initial ${\alpha}^{\prime}$ than in the contents of 2% and 33% initial ${\alpha}^{\prime}$. The difference of da/dN at the same level of ${\Delta}K$ was distinctive in low and intermediate level of ${\Delta}K$ however became less different as the level of ${\Delta}K$ increased. It is because the formation of strain induced martensite occurred readily in lower ${\alpha}^{\prime}$ at the vicinity of the fatigue crack tip, which causes compressive residual stresses resulting in the enhancement of crack closure. In general fatigue cracks propagated transgranular mode and many segments of ridges were observed on the fracture surfaces. At the higher contents of initial ${\alpha}^{\prime}$ appeared the smaller size of ridge segments. Slips in austenite were blocked more frequently by the martensite colonies formed in austenite.

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