• Title/Summary/Keyword: Center Loss

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Study on the Effects of Flows on the Acceleration of the Grooving Corrosion in the ERW Pipe (ERW강관에서 홈부식의 가속화에 미치는 유동의 영향에 관한 연구)

  • Kim, Jae-Seong;Kim, Yong;Lee, Bo-Young
    • Journal of Welding and Joining
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    • v.26 no.4
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    • pp.85-91
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    • 2008
  • The grooving corrosion is caused mainly by the different microstructures between the matrix and weld which is formed during the rapid heating and cooling cycle in welding. By this localized corrosion reaction of pipes, it evolves economic problems such as the early damage of industrial facilities and pipe lines of apartment, and water pollution. So lots of researches were carried out already about grooving corrosion mechanism of ERW carbon steel pipe but there is seldom study for water hammer happened by fluid phenomenon and corrosion rate by flow velocity. In this study, the analysis based on hydrodynamic and fracture mechanics was carried out. ANSYS, FLUENT and STAR-CD were used for confirmation of flow phenomenon and stress on the pipe. As the results, fatigue failure is able to be happened by water hammer and grooving corrosion rate is increased cause by turbulent. Grooving corrosion is happened on the pipe, then friction loss of fluid is occurred from corroded part. Erosion can be happened enough in corroded region of microscopic size that wear "V" form. Also pipe is able to be damaged by water hammer effects because of corroded region is general acting as a notch effects. Corrosion depth was more than half of total thickness, it can be damaged from water hammer pressure.

Occurrence of Weed Flora and Their Yield Loss in Angelica gigas Upland Fields of Minor Crop in Korea (소면적 재배작물인 당귀밭에 발생하는 잡초현황과 잡초에 의한 피해)

  • Lee, In-Yong;Kim, Chang-Seok;Lee, Jeongran;Seo, Young Jin;Kim, Jong-Su;Seo, Hyun-A;Jang, Hyung-Mok
    • Weed & Turfgrass Science
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    • v.5 no.2
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    • pp.65-70
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    • 2016
  • Investigation on weed flora in Angelica gigas upland fields was conducted to understand the current status of the weed flora and establish the control measures. Investigation was conducted twice, July and October in 2015. From this investigation, 105 species of 37 families including 27 exotics were identified and classified into 53 species of annuals, 24 species of biennials and 28 species of perennials. Dominance was the highest with Digitaria ciliaris, followed by Portulaca loeracea, Chenopodium album, Cyperus iria, Conyza canadensis, Galinsoga ciliata etc. in order. Chenopodium album was the highest in importance analysis and the followings were in order of Conyza canadensis, Galinsoga ciliata, Amaranthus lividus, Taraxacum offcinale etc. The yield of A. gigas was reduced 49.6% in no weeding plots comparing in weed managed plots.

Regulations of Reversal of Senescence by PKC Isozymes in Response to 12-O-Tetradecanoylphorbol-13-Acetate via Nuclear Translocation of pErk1/2

  • Lee, Yun Yeong;Ryu, Min Sook;Kim, Hong Seok;Suganuma, Masami;Song, Kye Yong;Lim, In Kyoung
    • Molecules and Cells
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    • v.39 no.3
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    • pp.266-279
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    • 2016
  • The mechanism by which 12-O-tetradecanoylphorbol-13-acetate (TPA) bypasses cellular senescence was investigated using human diploid fibroblast (HDF) cell replicative senescence as a model. Upon TPA treatment, protein kinase C (PKC) ${\alpha}$ and $PKC{\beta}1$ exerted differential effects on the nuclear translocation of cytoplasmic pErk1/2, a protein which maintains senescence. $PKC{\alpha}$ accompanied pErk1/2 to the nucleus after freeing it from $PEA-15pS^{104}$ via $PKC{\beta}1$ and then was rapidly ubiquitinated and degraded within the nucleus. Mitogen-activated protein kinase docking motif and kinase activity of $PKC{\alpha}$ were both required for pErk1/2 transport to the nucleus. Repetitive exposure of mouse skin to TPA downregulated $PKC{\alpha}$ expression and increased epidermal and hair follicle cell proliferation. Thus, $PKC{\alpha}$ downregulation is accompanied by in vivo cell proliferation, as evidenced in 7, 12-dimethylbenz(a)anthracene (DMBA)-TPA-mediated carcinogenesis. The ability of TPA to reverse senescence was further demonstrated in old HDF cells using RNA-sequencing analyses in which TPA-induced nuclear $PKC{\alpha}$ degradation freed nuclear pErk1/2 to induce cell proliferation and facilitated the recovery of mitochondrial energy metabolism. Our data indicate that TPA-induced senescence reversal and carcinogenesis promotion share the same molecular pathway. Loss of $PKC{\alpha}$ expression following TPA treatment reduces pErk1/2-activated SP1 biding to the $p21^{WAF1}$ gene promoter, thus preventing senescence onset and overcoming G1/S cell cycle arrest in senescent cells.

Functions of TET Proteins in Hematopoietic Transformation

  • Han, Jae-A;An, Jungeun;Ko, Myunggon
    • Molecules and Cells
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    • v.38 no.11
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    • pp.925-935
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    • 2015
  • DNA methylation is a well-characterized epigenetic modification that plays central roles in mammalian development, genomic imprinting, X-chromosome inactivation and silencing of retrotransposon elements. Aberrant DNA methylation pattern is a characteristic feature of cancers and associated with abnormal expression of oncogenes, tumor suppressor genes or repair genes. Ten-eleven-translocation (TET) proteins are recently characterized dioxygenases that catalyze progressive oxidation of 5-methylcytosine to produce 5-hydroxymethylcytosine and further oxidized derivatives. These oxidized methylcytosines not only potentiate DNA demethylation but also behave as independent epigenetic modifications per se. The expression or activity of TET proteins and DNA hydroxymethylation are highly dysregulated in a wide range of cancers including hematologic and non-hematologic malignancies, and accumulating evidence points TET proteins as a novel tumor suppressor in cancers. Here we review DNA demethylation-dependent and -independent functions of TET proteins. We also describe diverse TET loss-of-function mutations that are recurrently found in myeloid and lymphoid malignancies and their potential roles in hematopoietic transformation. We discuss consequences of the deficiency of individual Tet genes and potential compensation between different Tet members in mice. Possible mechanisms underlying facilitated oncogenic transformation of TET-deficient hematopoietic cells are also described. Lastly, we address non-mutational mechanisms that lead to suppression or inactivation of TET proteins in cancers. Strategies to restore normal 5mC oxidation status in cancers by targeting TET proteins may provide new avenues to expedite the development of promising anti-cancer agents.

Effects of Pumpkin (Cucurbita maxima Duch.) Fiber on Physicochemical Properties and Sensory Characteristics of Chicken Frankfurters

  • Choi, Yun-Sang;Kim, Hyun-Wook;Hwang, Ko-Eun;Song, Dong-Heon;Park, Jae-Hyun;Lee, Soo-Yeon;Choi, Min-Sung;Choi, Ji-Hun;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.32 no.2
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    • pp.174-183
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    • 2012
  • The effects of dietary fiber extracted from pumpkin (pumpkin fiber) on physicochemical properties, textural properties, and sensory characteristics of chicken frankfurters were investigated. Chicken frankfurter was supplemented with pumpkin fiber at levels of 0, 1, 2, 3, and 4%. Adding different levels of pumpkin fiber affected the proximate composition of the chicken frankfurters (p<0.05), except for protein content. In addition of different levels of pumpkin fiber influenced the physicochemical and textural properties of the chicken frankfurters (p<0.05). The yellowness, viscosity, and hardness were higher in chicken frankfurters samples containing pumpkin fiber than those in the control (p<0.05). The results showed that chicken frankfurter samples with higher pumpkin fiber levels had lower lightness values (p<0.05), as well as less cooking loss, emulsion stability, and lower color scores (p<0.05) compared to those control without pumpkin fiber treatment. The chicken frankfurters with 2% and 3% pumpkin fiber had higher overall acceptability than that of the control (p<0.05). The results show that adding pumpkin fiber produced acceptable chicken frankfurters and improved their quality characteristics.

Effect of Pre-rigor Salting Levels on Physicochemical and Textural Properties of Chicken Breast Muscles

  • Kim, Hyun-Wook;Hwang, Ko-Eun;Song, Dong-Heon;Kim, Yong-Jae;Ham, Youn-Kyung;Yeo, Eui-Joo;Jeong, Tae-Jun;Choi, Yun-Sang;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.35 no.5
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    • pp.577-584
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    • 2015
  • This study was conducted to evaluate the effect of pre-rigor salting level (0-4% NaCl concentration) on physicochemical and textural properties of pre-rigor chicken breast muscles. The pre-rigor chicken breast muscles were de-boned 10 min post-mortem and salted within 25 min post-mortem. An increase in pre-rigor salting level led to the formation of high ultimate pH of chicken breast muscles at post-mortem 24 h. The addition of minimum of 2% NaCl significantly improved water holding capacity, cooking loss, protein solubility, and hardness when compared to the non-salting chicken breast muscle (p<0.05). On the other hand, the increase in pre-rigor salting level caused the inhibition of myofibrillar protein degradation and the acceleration of lipid oxidation. However, the difference in NaCl concentration between 3% and 4% had no great differences in the results of physicochemical and textural properties due to pre-rigor salting effects (p>0.05). Therefore, our study certified the pre-rigor salting effect of chicken breast muscle salted with 2% NaCl when compared to post-rigor muscle salted with equal NaCl concentration, and suggests that the 2% NaCl concentration is minimally required to ensure the definite pre-rigor salting effect on chicken breast muscle.

Effect of Oyster Shell Calcium Powder on the Quality of Restructured Pork Ham

  • Choi, Jung-Seok;Lee, Hyun-Jin;Jin, Sang-Keun;Lee, Hyun-Joo;Choi, Yang-Il
    • Food Science of Animal Resources
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    • v.34 no.3
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    • pp.372-377
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    • 2014
  • This study was conducted to evaluate the effects of oyster shell calcium powder (OSCP) as a substitute for phosphates in curing agent, on the quality of restructured pork ham. Restructured pork ham was processed under six treatment conditions: T1 (no additives), T2 (0.3% sodium tripolyphosphate), T3 (1.5% NaCl+0.5% whey protein), T4 (1.5% NaCl+0.5% whey protein+0.15% OSCP), T5 (1.5% NaCl+0.5% whey protein+0.3% OSCP), and T6 (1.5% NaCl+0.5% whey protein+0.5% OSCP). Addition of OSCP significantly increased the ash content and pH of restructured pork ham (p<0.05), but did not affect the cooking loss and water holding capacity values of restructured pork ham. Addition of OSCP had no effect on Hunter a and b surface color values of restructured pork ham, but did decrease the Hunter L surface color value (p<0.05). The addition of 0.5% OSCP showed significantly higher chewiness and springiness values of restructured pork ham, compared with the addition of phosphates (p<0.05). In conclusion, the addition of OSCP combined with low NaCl and 0.5% whey protein can be considered a viable substitute for phosphates in the curing agent, when processing restructured pork ham.

Comparison of Physicochemical and Functional Traits of Hanwoo Steer Beef by the Quality Grade

  • Lim, Dong-Gyun;Cha, Ju-Su;Jo, Cheorun;Lee, Kyung Haeng;Kim, Jong-Ju;Nam, Ki-Chang
    • Food Science of Animal Resources
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    • v.34 no.3
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    • pp.287-296
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    • 2014
  • The physicochemical and functional traits for loin muscles of Hanwoo steers were compared by quality grade (QG). A total of 500 Hanwoo steers were slaughtered, their carcasses were categorized into four groups (QG 1++, 1+, 1, and 2), and the longissimus dorsi muscles were analyzed. QG 1++ group had the highest fat and lowest moisture content (p<0.05). QG 1++ showed higher $L^*$ and $b^*$ color values, higher cooking loss, and lower shear force values, compared with the other groups (p<0.05). The flavor, tenderness, juiciness, and preference scores by sensory evaluation were highly ranked for premium QG groups (1++ and 1+). Regarding the micro compounds, QG 1 and QG 2 had greater amounts of inosine monophosphate, and QG 2 had greater amounts of anserine, carnosine, and creatine, than QG 1++ (p<0.05). QG 1++ and 1+ had higher percentages of oleic acid (C18:1) than QG 2 (p<0.05). Within premium QG 1++ and 1+, the results of the nucleotides, free amino acids, dipeptides, and fatty acids did not show any distinctive differences. Hanwoo beef as determined by the current grading system was not significantly different in terms of functional components; the only significant difference was in intramuscular fat content.

Physicochemical Traits, Fatty Acid and Free Amino Acid Compositions of Two-way Crossbred Pork Belly

  • Lim, Dong-Gyun;Kim, Kyung-Tai;Lee, Kyung-Haeng;Seo, Kang-Seok;Nam, Ki-Chang
    • Food Science of Animal Resources
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    • v.33 no.2
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    • pp.189-197
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    • 2013
  • This study was conducted to determine the meat quality characteristics of pork belly from 3 different two-way crossbreeds of Yorkshire${\times}$Landrace (YL), Yorkshire${\times}$Berkshire (YB), and Yorkshire${\times}$Chester White (YC), which were domesticated for Korean consumers. Twenty pigs from each crossbreed (total n=60) were randomly selected when they reached the 110-120 kg range of market weight, slaughtered, and cooled at $0^{\circ}C$ for 24 h. The pork bellies on the left side of the cooled carcasses were then sampled and analyzed. The pH of pork bellies was the lowest in YC among the crossbreds. There was no significant difference in fat content by crossbred, but YB bellies had the lowest moisture content (p<0.05). The cooking loss of YB bellies was lower than those of others (p<0.05). The TBARS values in YB was significantly higher than those of the others at 14 d. YL bellies had a higher percentage of stearic acid, oleic acid, and MUFA than the other breeds, while YB and YC had a higher percentage of myristic acid, linoleic acid, linolenic acid, and n-6 fatty acids than the YB (p<0.05). PUFA content and P/S were significantly higher in YC compared with YL. Except for arginine, the concentrations of most free amino acids were higher in YB bellies than in others, (p<0.05). Sensory evaluation scores of bellies were higher for YC than for other breeds (p<0.05).

Comparison of Meat Quality and Fatty Acid Composition of Longissimus Muscles from Purebred Pigs and Three-way Crossbred LYD Pigs

  • Choi, Yeong-Seok;Lee, Jin-Kyu;Jung, Ji-Taek;Jung, Young-Chul;Jung, Jong-Hyun;Jung, Myung-Ok;Choi, Yang-Il;Jin, Sang-Keun;Choi, Jung-Seok
    • Food Science of Animal Resources
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    • v.36 no.5
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    • pp.689-696
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    • 2016
  • This study was conducted to find pork quality to meet the needs of consumers. Thus, the meat quality and fatty acid composition of longissimus muscles from purebred pigs (Landrace, Yorkshire, and Duroc) and three-way crossbred LYD pigs were compared and evaluated. Chemical compositions of longissimus muscles were significant (p<0.05) different among pigs. Duroc contained significant (p<0.05) higher fat contents than other pigs, whereas significant (p<0.05) higher moisture contents were observed in Landrace, Yorkshire, and LYD pigs compared to those of Duroc pigs. The values of pH24 h and pH14 d were the highest in Landrace pigs. Myoglobin contents of LYD pigs were higher (p<0.05) than those of purebred pigs. Regarding meat color, Duroc and Yorkshire pigs had higher redness values than Landrace and LYD pigs, while Landrace pigs had the lowest (p<0.05) color values among all pigs. There was no significant difference in shear force or water holding capacity (WHC). Duroc pigs maintained the lowest drip loss during 14 d of cold storage. In sensory evaluation, the marbling scores of Duroc pigs were higher (p<0.05) than other pigs. Regarding fatty acid compositions, total USFA, poly-, n-3, and n-6 contents were the highest (p<0.05) in LYD pigs, while total SFA contents were the highest (p<0.05) in Duroc pigs. Based on these results, purebred pigs had superior overall meat quality to crossbred pigs.