• Title/Summary/Keyword: 3′-End formation

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Cutting Force Variation Characteristics in End Milling of Terrace Volume (계단형상 체적의 엔드밀 가공시 절삭력 변화 특성에 관한 연구)

  • Maeng, Heeyoung
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.3_1spc
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    • pp.489-495
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    • 2013
  • This study analyzed thevariation in the cutting force when the cutting area of a terrace volume is machined, which is generally left after the rough cutting of a sculptured surface. The numerically simulated results for the cutting forces are compared with cutting force measurements by considering the theoretical prediction of the cutting area formation and specific cutting volume. The variation in the cutting force is measured using a dynamometer installed on a machining center for 19 different kinds of test pieces, which are selected according to the variation in the terrace volume factor, tool diameter factor, and cutting depth factor. As a result, it is verified that the cutting forces evaluated by the numerical analysis coincide with the measured cutting forces, and it is proposed as a practical cutting force prediction model.

Validation of 3D crack propagation in plain concrete -Part I: Experimental investigation - the PCT3D test

  • Feist, C.;Hofstetter, G.
    • Computers and Concrete
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    • v.4 no.1
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    • pp.49-66
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    • 2007
  • The objective of this paper is to provide experimental data on the propagation of curved crack-surfaces and the respective load-displacement diagrams for the validation of numerical models for cracking of concrete, subjected to three-dimensional stress states. To this end beam-shaped specimens are subjected to combined bending and torsional loading, leading to the formation of a spatially curved crack-surface. The experimental data contain the evolution of the load and of the strains at selected points in terms of the crack mouth opening displacement and the propagation of the crack surface.

In vitro Formation of Tuberous Roots from Root Ends in the Rooted Tuberous stem without shoots in Cyclamen persicum MILL.

  • Lim, Jong-Gu;Junzo, Fujigaki
    • Plant Resources
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    • v.7 no.3
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    • pp.222-225
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    • 2004
  • In Japan, propagation of cyclamen is mainly from seedlings. However, seeds are expensive and germination is slow and non..uniform. Therefore, to achieve genetically uniform propagation, multiplication must be vegetative. The rooted tuberous stems without shoots as sources of explants were cultured on the media containing BA and sucrose. After 30 days cultivation, tuberous roots were produced from the root ends attached to a tuberous stem and its capability was dependent on the type of media. The highest percentage of tuberous root formation was observed in Culture on the medium of 1/3 MS containing 0.05mgL$^{-1}$ NAA, 0.5mg L$^{-1}$ BA and 5% sucrose. Growth rates of the tuberous roots were greatly influenced by the cutting positions of a root in explants. The highest growth of was observed if small amount of root end was cut at initiation of tissue culture.

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Molecular gas and star formation in early-type galaxies

  • Bureau, Martin
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.65-65
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    • 2011
  • Early-type galaxies represent the end point of galaxy evolution and, despite pervasive residual star formation, are generally considered "red and dead", that is composed exclusively of old stars with no star formation. Here, their molecular gas content is constrained and discussed in relation to their evolution, supporting the continuing importance of minor mergers and/or cold gas accretion. First, as part of the Atlas3D survey, the first complete, large, volume-limited survey of CO in normal early-type galaxies is presented. At least of 23% of local early-types possess a substantial amount of molecular gas, the necessary ingredient for star formation, independent of mass and environment but dependent on the specific stellar angular momentum. Second, using CO synthesis imaging, the extent of the molecular gas is constrained and a variety of morphologies is revealed. The kinematics of the molecular gas and stars are often misaligned, implying an external gas origin in over a third of all systems, more than half in the field, while external gas accretion must be shot down in clusters. Third, many objects appear to be in the process of forming regular kpc-size decoupled disks, and a star formation sequence can be sketched by piecing together multi-wavelength information on the molecular gas, current star formation, and young stars. Fourth, early-type galaxies do not seem to systematically obey all our usual prejudices regarding star formation (e.g. Schmidt-Kennicutt law, far infrared-radio continuum correlation), suggesting a greater diversity in star formation processes than observed in disk galaxies and the possibility of "morphological quenching". Lastly, a first step toward constraining the physical properties of the molecular gas is taken, by modeling the line ratios of density- and opacity-sensitive molecules in a few objects. Taken together, these observations argue for the continuing importance of (minor) mergers and cold gas accretion in local early-types, and they provide a much greater understanding of the gas cycle in the galaxies harbouring most of the stellar mass. In the future, better dust masses and dust-to-gas mass ratios from Herschel should allow to place entirely independent constraints on the gas supply, while spatially-resolved high-density molecular gas tracers observed with ALMA will probe the interstellar medium and star formation laws locally in a regime entirely different from that normally probed in spiral galaxies.

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Degraded Products Induced by Gamma-Irradiation of Mangiferin with Anti-Diabetic Complication Effects (감마선 조사에 의한 Mangiferin 변화물의 항당뇨합병증 활성)

  • Jeong, Gyeong Han;Kim, Tae Hoon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.11
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    • pp.1414-1418
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    • 2017
  • Inhibition of advanced glycation end product (AGE) formation is a valuable therapeutic strategy for the regulation of diabetic complications. This study was conducted to identify potential therapeutic targets of anti-diabetic complications from irradiated mangiferin using AGE formation assay. Radiolytic degradation of the xanthone glucoside mangiferin by gamma-irradiation resulted in three degraded mangiferin analogues: mangiferdiol (1), mangiferinol (2), and isomangiferinol (3). Structures of the three newly generated compounds were characterized by interpretation of nuclear magnetic resonance ($^1H$, $^{13}C$ NMR, $^1H-^1H$ COSY, HSQC, HMBC, and NOESY) and mass spectroscopic data. The anti-diabetic complication of the generated mangiferin derivatives were tested using in vitro AGE formation method. Among the tested degraded products, mangiferinol (2) and isomangiferinol (3) exhibited significantly improved potency against AGE formation inhibitory activities with $IC_{50}$ values of $5.6{\pm}0.8$ and $7.6{\pm}0.9{\mu}M$, respectively. This result implies that xanthone derivatives generated from gamma-irradiated mangiferin might be beneficial for prevention of diabetic complication and related diseases.

Surgical Management of Trachea Stenosis (기관협착증에 대한 기관 성형술)

  • 김치경
    • Journal of Chest Surgery
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    • v.25 no.12
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    • pp.1508-1515
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    • 1992
  • Between 1975 and 1992, forty five patients with trachea stenosis received tracheoplasty for relief of obstruction. The causes of airway problem are brain contusion[19 cases, 40%], cerebrovascular disease[3 cases, 7%], drug intoxication[8 cases, 18%], psychotic problem[2 cases, 4%], trachea tumor[3 cases, 7%], adult respiratory distress syndrome[9 cases, 20%] and direct trauma[1 case, 2%]. Direct causes of trachea stenosis were complications of tracheostomy[36 cases, 80%], complications of nasotracheal intubation[5 cases, 11%], tumor[3 cases, 6%] and trauma[1 case, 2%]. Thirty one patients underwent the sleeve resection and end-to-end anastomosis. Five patients performed a wedge resection and end-to-end anastomosis. Forteen patients received the Montgomery T-tube for relief of airway obstruction. Four patients have done simple excision of granulation tissue. Two, subglottic stenosis patients were received Rethi procedure[anterior division of cricoid cartilage, wedge partial resection of lower thyroid cartilage and Montgomery T-tube molding] and the other subglottic stenosis patient underwent permanent trachea fenestration. Including cervical flexion in all patients postoperatively, additional surgical techniques for obtain tension-free anastomosis were hyoid bone release technique in two cases, and hilar mobilization, division of inferior pulmonary ligament and mobilization of pulmonary vessel at the pericardium were performed in one case. Cervical approach was used in 39 cases, cervicomediastinal in 12 cases and transthoracic in one case. Complications of tracheoplasty were formation of granulation tissue at the anastomosis site[3 cases], restenosis[9 cases], trachea-innominate artery fistula[2 cases], wound infection[2 cases], separation of anastomosis[2 cases], air leakage[3 cases], injury to a recurrent laryngeal nerve[temporary 8 cases, permanent 2 cases] and hypoxemia[1 case]. Surgical mortality for resection with primary reconstruction was 6.7%, with one death due to postoperative respiratory failure and two deaths due to tracheo-innominate artery fistula.

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Role of Advanced Glycation End Products in TGF-β1 and Fibronectin Expression in Mesangial Cells Cultured under High Glucose

  • HA Hunjoo;KIM Hwa-Jung;LEE Hi Bahl
    • Biomolecules & Therapeutics
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    • v.13 no.3
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    • pp.190-197
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    • 2005
  • Advanced glycation end products (AGE) have been implicated in the pathogenesis of diabetic complications including nephropathy. However, the role of AGE in the activation of mesangial cells cultured under high glucose has not been elucidated. The effects of aminoguanidine, which prevents formation of AGE and protein cross-linking, on the synthesis of $TGF-{\beta}1$ and fibronectin by rat mesangial cells cultured under high glucose for 2 weeks were examined and compared with the effects of $N^G$-nitro-L-arginine methyl ester (NAME), a selective nitric oxide synthase inhibitor, because aminoguanidine also inhibits the inducible nitric oxide synthase. Culture of mesangial cells in 30 mM (high) glucose for 2 weeks induced 1.5-fold (ELISA) and 1.9-fold (Western blot analysis) increase in AGE in the culture media compared to 5.6 mM (control) glucose. Northern blot analysis revealed 1.5-fold increase in $TGF-{\beta}1$ and 1.7-fold increase in fibronectin mRNA expression in cells cultured under high glucose compared to control glucose. Increases in mRNA expression were followed by increased protein synthesis. Mink lung epithelial cell growth inhibition assay revealed 1.4-fold increase in $TGF-{\beta}1$ protein in high glucose media compared to control. Fibronectin protein also increased 2.1-fold that of control glucose by Western blot analysis. Administration of aminoguanidine suppressed AGE formation in a dose dependent manner and at the same time suppressed $TGF-{\beta}1$ and fibronectin synthesis by mesangial cells cultured in both control and high glucose. In contrast, NAME did not affect high glucose-induced changes. These findings support a role for AGE in high glucose-induced upregulation of $TGF-{\beta}1$ and fibronectin synthesis by mesangial cells.

A Study on the Formation Factors of Grotesque Image expressed in Fashion (복식에 표현된 그로테스크 이미지의 형성 요인에 관한 연구)

  • 남미현
    • Journal of the Korea Fashion and Costume Design Association
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    • v.4 no.3
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    • pp.43-54
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    • 2002
  • Some factors had influence upon the grotesque image formation expressed in fashion: for instance, thanatos, religions, fin de siecle (end of the century), the aesthetics of ugliness, subculture group's resistance and technology development, etc. Those factors have formed a grotesque while exchanging influence each other, and have following features: First, the thanatos, which is destructive and aggressive instinct of the inner world of human being, creates frightening object and motif to form the images of grotesque. Second, from religious point of view, the church made the Devil a tool for maintenance of power: They manipulated physical body and give a damage to it to sublimate it in holy existence, so that they could feel catharsis. Third, there was fin de siecle (end of the century) to let people have negative life attitude, such as uneasiness on following century, eschatology, skepticism and nihilism, etc. Fourth, the ugliness having unpleasantness and disharmony occupies governing position when our society becomes corrupted and uneasy, and the aesthetics of ugliness discloses the inconsistency of ideal and beautiful life in the grotesque images. Fifth, subculture groups, i.e., the lower classes, homosexual and the youth's group, etc, form the grotesque images by political and ideological resistance, complaints and specific identity, etc concerning governing culture keeping traditional ethics consciousness. Sixth, recent technology development has destroyed a boundary between human being and machinery, and bio-technology development has created transplant operation, plastic operation and other human body transformation operations, and genome research, etc has raised human being's identity.

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THE INITIAL CONDITIONS AND EVOLUTION OF ISOLATED GALAXY MODELS: EFFECTS OF THE HOT GAS HALO

  • Hwang, Jeong-Sun;Park, Changbom;Choi, Jun-Hwan
    • Journal of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.1-32
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    • 2013
  • We construct several Milky Way-like galaxy models containing a gas halo (as well as gaseous and stellar disks, a dark matter halo, and a stellar bulge) following either an isothermal or an NFW density profile with varying mass and initial spin. In addition, galactic winds associated with star formation are tested in some of the simulations. We evolve these isolated galaxy models using the GADGET-3 N-body/hydrodynamic simulation code, paying particular attention to the effects of the gaseous halo on the evolution. We find that the evolution of the models is strongly affected by the adopted gas halo component, particularly in the gas dissipation and the star formation activity in the disk. The model without a gas halo shows an increasing star formation rate (SFR) at the beginning of the simulation for some hundreds of millions of years and then a continuously decreasing rate to the end of the run at 3 Gyr. Whereas the SFRs in the models with a gas halo, depending on the density profile and the total mass of the gas halo, emerge to be either relatively flat throughout the simulations or increasing until the middle of the run (over a gigayear) and then decreasing to the end. The models with the more centrally concentrated NFW gas halo show overall higher SFRs than those with the isothermal gas halo of the equal mass. The gas accretion from the halo onto the disk also occurs more in the models with the NFW gas halo, however, this is shown to take place mostly in the inner part of the disk and not to contribute significantly to the star formation unless the gas halo has very high density at the central part. The rotation of a gas halo is found to make SFR lower in the model. The SFRs in the runs including galactic winds are found to be lower than those in the same runs but without winds. We conclude that the effects of a hot gaseous halo on the evolution of galaxies are generally too significant to be simply ignored. We also expect that more hydrodynamical processes in galaxies could be understood through numerical simulations employing both gas disk and gas halo components.

Skin Wrinkle Improvement Effect of Paeoniae radix and processed Paeoniae radix Through inhibition of Advanced glycation end products (AGEs) (작약 및 포제작약의 최종당화산물 억제를 통한 피부 주름 개선 효과)

  • Kim, SuJi;Lee, AhReum;Kim, SooHyun;Kim, KyeongJo;Kwon, OJun;Choi, JoonYoung;Koo, JinSuk;Roh, Seong-Soo
    • The Korea Journal of Herbology
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    • v.32 no.4
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    • pp.53-60
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    • 2017
  • Objectives : Collagen decrease of Skin appears through various path ways. One of causes may be the Advanced glycation endproducts (AGEs) that combine formation of glucose and protein. The aim of this study was to explore the prevent wrinkle formation of Paeoniae radix (PR) and heated Paeoniae radix (HPR) via AGEs path way. Methods : AGEs formation inhibitory activities of PR and HPR measured using bovine serum albumin, glucose, and fructose. To evaluate the protective effects of PR and HPR in diabetic rats induced with streptozotocin (STZ) and methyl glyoxal (MGO), SD rat were distributed into four groups. Normal rats (Nor), AGEs-induced rats (Con), AGEs-induced rats treated with 100 mg/kg PR(PR), AGEs-induced rats treated with 100 mg/kg HPR (HPR). To induce AGEs, streptozotocin (50 mg/kg) was administered intraperitoneally and after 3 days administrated 100mM methyl glyoxal for 3 weeks. Results : The oral administration of HPR inhibited AGEs in skin tissues compared with PR. The increased reactive oxygen species (ROS) levels in the serum were diminished by HPR treatment. The analyses of kidney and skin tissues proteins indicated that HPR treatment effectively reduced AGEs related protein levels as compared to that by PR treatment. Also, HPR decreased anti-oxidant related protein levels in skin tissues such as catalase, glutathione peroxidase. Moreover, it inhibited the reduction of COL1A2 by decreasing MMP-1. Conclusion : Based on these results, it was suggested that PR and HPR could have Improving effects on wrinkle formation. These evidences provide useful information for the development wrinkle formation treated agent.