• Title/Summary/Keyword: abnormal transition

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Anatomical Characteristics of Bisected Compression Woods and Their Intervened Wood in a Stem of Pinus densiflora S. et Z. (소나무(Pinus densiflora S. et Z.)수간내(樹幹內)에 양분형성(兩分形成)된 압축이상재(壓縮異常材)와 그 사이에 존재(存在)하는 간재(間材)의 해부학적(解剖學的) 특성(特性))

  • Lee, Phil-Woo;Chung, Youn-Jib
    • Journal of the Korean Wood Science and Technology
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    • v.16 no.2
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    • pp.42-49
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    • 1988
  • Anatomical characteristics on abnormal type of bisected compression woods and light colored wood intervened between these dark colored compression woods on under part and their respective opposite woods on upper parts of cross section in Pinus densiflora S. et Z. stem were compared through optical microscopic investigation. and the obtained results were summarized as follows: 1. Tracheid length increased linearly as the number of rings from the pith increases in all investigated parts, but increasing tendency in tracheid length was similar within bisected two compression woods and their opposite woods. 2. Tracheids were the shortest in bisected two compression woods and tracheid length in intervened wood between these two compression woods was longer than in compression woods but shorter than in the opposite woods. 3. Bisected two compression woods and intervened wood between these two compression woods revealed similar features in tracheid transition from springwood to summerwood, intercellular space, tracheid entanglement, and cross sectional view of tracheid. but spiral check was observed only in these two compression woods, therefore the intervened wood between these two compression woods disclosed anatomical characteristics similar to, not typical of, compression woods.

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Effect of MLN8237, a Novel Aurora A Kinase Inhibitor, on the Spontaneous Fragmentation of Ovulated Mouse Oocytes

  • Park, Ji-Hun;Choi, Tae-Saeng
    • Reproductive and Developmental Biology
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    • v.35 no.4
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    • pp.499-502
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    • 2011
  • Aurora A kinase is a mitotic serine/threonine kinase whose proposed functions include the maturation of centrosomes, G2/M transition, alignment of chromosomes at metaphase, and cytokinesis. In this study, we investigated the effect of MLN8237, an aurora A kinase inhibitor, on the postovulatory aging of oocytes based on the frequency of oocyte fragmentation, cdk1 kinase activity, and cyclin B degradation. The fragmentation of ovulated oocytes during prolonged culture was inhibited by treatment with MLN8237 in a concentration-dependent manner. The frequency of fragmented oocytes was significantly lower in oocytes treated with 2 ${\mu}M$ MLN8237 (13%) than in control oocytes (64%) after two days of culture. Most of the control (non-fragmented) oocytes (91%) were activated after two days of culture. In comparison, only 22% of the MLN8237-treated oocytes were activated; the rest of the oocytes (78%) were still in metaphase with an abnormal spindle and dispersed chromosomes. Next, cdk1 activity and the level of cyclin B were examined. The level of cyclin B and cdk1 activity in MLN8237-treated oocytes were nearly equal to those in control oocytes. Our results indicate that MLN8237 inhibited the fragmentation of ovulated oocytes during prolonged culture, although it blocked the spontaneous decrease in activity of cdk1 and degradation of cyclin B. This mechanism of inhibition is different from that in oocytes treated with nocodazole, which have high levels of cdk1 activity and cyclin B.

Requirement of Bni5 Phosphorylation for Bud Morphogenesis in Saccharomyces cerevisiae

  • Nam, Sung-Chang;Sung, Hye-Ran;Chung, Yeon-Bok;Lee, Chong-Kil;Lee, Dong-Hun;Song, Suk-Gil
    • Journal of Microbiology
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    • v.45 no.1
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    • pp.34-40
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    • 2007
  • In budding yeast, G2/M transition is tightly correlated with bud morphogenesis regulated by Swel and septin that plays as a scaffold to recruits protein components. BNI5 isolated as a suppressor for septin defect is implicated in septin organization and cytokinesis. The mechanism by which Bni5 regulates normal septin function is not completely understood. Here, we show that Bni5 phosphorylation is required for mitotic entry regulated by Swel pathway. Bni5 modification was evident from late mitosis to G1 phase, and CIP treatment in vitro of affinity-purified Bni5 removed the modification, indicative of phosphorylation on Bni5. The phosphorylation-deficient mutant of BNI5 (bni5-4A) was defective in both growth at semi-restrictive temperature and suppression of septin defect. Loss of Bni5 phosphorylation resulted in abnormal bud morphology and cell cycle delay at G2 phase, as evidenced by the formation of elongated cells with multinuclei. However, deletion of Swel completely eliminated the elongated-bud phenotypes of both bni5 deletion and bni5-4A mutants. These results suggest that the bud morphogenesis and mitotic entry are positively regulated by phosphorylation-dependent function of Bni5 which is under the control of Swel morphogenesis pathway.

Fate of Donor Centrosome and Microtubule Dynamics of Porcine Somatic Cell Nuclear Transfer Embryos

  • Kwon, Dae-Jin;Park, Choon-Keun;Yang, Boo-Keun;Cheong, Hee-Tae
    • Reproductive and Developmental Biology
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    • v.34 no.2
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    • pp.73-79
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    • 2010
  • We investigated the microtubule dynamics, including the inheritance of donor centrosomes and the mitotic spindle assembly occurring during the first mitosis of somatic cell nuclear transfer (SCNT) embryos in pigs. SCNT embryos were fixed 15 min and 1 h after fusion in order to assess the inheritance pattern of the donor centrosome. The distribution and dynamic of the centrosome and microtubule during the first mitotic phase of SCNT embryos were also evaluated. The frequency of embryos evidencing $\gamma$-tubulin spots (centrosome) was 93.2% in the SCNT embryos 15 min after fusion. In the majority of the SCNT embryos (61.5%), however, no centrosome was observed 1 h after fusion. The frequency of the embryos with no or abnormal mitotic spindles 20 h after fusion was 19.6%. The $\gamma$-tubulin spots were detected near the nuclei of somatic cells regardless of cell cycle phase, whereas $\gamma$-tubulin spots in the SCNT embryos were observed only during the inter-anaphase transition. These results showed that the donor centrosome is inherited into the SCNT embryos, but failed to assemble the normal mitotic spindles during first mitotic phase in some SCNT embryos.

A Study on Aesthetic Characteristics of Fur Fashion (모피 패션의 미적 특성에 관한 연구)

  • Hwang, Jae-Yun;Kim, Jeong-Mee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.19 no.1
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    • pp.55-70
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    • 2017
  • This study researched transition process of fur costume from ancient times to 20th century, extracted esthetic characteristics, and then understood how the esthetic characteristics appear in the recent fur collection. The result is as follows. First, magical meaning was revealed on leopard fur that ancient chief priests wore on top of shenti to symbolize immorality and fur tunics to which christian symbol was added in Byzantine. During middle age and the Renaissance, extravagance appeared on sable and amin jackets that the noble decorated to show off their high status. During the rococo age and mid-20th century, sensuality and elegance appeared on the fur dresses that the female body was emphasized. Second, in recent collection, extravagance appeared on over-sized and voluminous fox-coat, sexsuality and elegance were revealed through mink-dresses and jackets with soft touch and gloss that curved-silhouette was emphasized. In addition, practicality and functionality were shown through short length and light, soft material, and activeness was in the mink jacket to which functional elements such as zippers and rubber were added. To pursue uniqueness and fun, fox jackets were made with over-sized vivid green color. Besides, abnormality and vulgarness appeared through the fashion with abnormal and distracted images with ambiguous forms and new processing methods applied.

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Differential Scanning Calorimetric and Thermogravimetric Analysis of Silk Fibroin / poly (Vinyl pyrrolidone) (견단백질 / Poly (Vinyl pyrrolidone)의 열특성)

  • Kweon, Hae-Yong;Lee, Kwang-Gill;Yeo, Joo-Hong;Woo, Soon-Ok;Han, Sang-Mi
    • Journal of Sericultural and Entomological Science
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    • v.49 no.2
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    • pp.77-80
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    • 2007
  • Silk fibroin/poly (vinyl pyrrolidone) conjugates were prepared and characterized through differential thermal calorimeter and thermogravimetry. The glass transition temperature (Tg) of poly (vinyl pyrrolidone) was not changed by reaction with silk fibroin. However, abnormal exothermic peak was observed at the silk fibroin/poly (vinyl pyrrolidone) conjugates. Thermogravimetric analysis showed that thermal stability of silk fibroin was relatively increased by reaction with PVP.

Effect of Heat Treatment on the Martensitic Transformation and Tensile Deformation Behavior in Ti-Ni-B shape Memory Alloy (Ti-Ni-B 형상기억합금의 마르텐사이트변태 및 인장변형거동에 미치는 열처리의 영향)

  • Lee, O.Y.;Park, Y.K.;Ahn, H.K.
    • Journal of the Korean Society for Heat Treatment
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    • v.8 no.1
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    • pp.75-83
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    • 1995
  • The purpose of this study is to investigate the effect of heat treatments on the martensite transformation and tensile deformation behavior in Ti-Ni-B alloys with various boron concentration. Three types of heat treatment are given to the specimens; i) solution treatment ii) aging iii) thermo-mechanical treatment. In solution treated specimens. R-phase transition which is related to abnormal increase of electrical resistance prior to martensitic transformation has been formed at a boron content of 0.2at % and the $M_s$ temperature has been decreased with the increasing of boron content. However. It has not been affected by aging, while that of thermo-mechanically treated specimens has been remarkably increased in the vicinity of recrystallization temperature. The thermo-mechanically treated specimen has showed a good thermal fatigue characteristics, shape memory effect and superelasticity in comparison with the solution treated specimen.

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Challenges for the realization of carbon neutrality and air pollution improvement in major Northeast Asian countries: The importance of transitioning to eco-friendly EV industry and the necessity of developing lightweight materials

  • Sung-Hyung Lee;Hitoshi Yashiro;Song-Zhu Kure-Chu
    • Journal of Surface Science and Engineering
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    • v.56 no.1
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    • pp.12-39
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    • 2023
  • Diseases caused by air pollution and abnormal climate are occurring worldwide due to global warming. Accordingly, the international community has established a strategy to respond to climate change, and major countries have shifted their economic policies to eco-friendly industries. In this study, we investigate the current status of the renewable energy industry and that of responses to carbon neutrality and PM2.5 (air pollution) in the three major Northeast Asian countries of Japan, Korea, and China, covering changes in the corporate perceptions of Environment, Social, Governance and RE100. In more detail, the three major Northeast Asian countries, referred to as the climate villains in the international community, explain the importance of successful entry into the electric vehicles (EV) industry for a rapid transition to an eco-friendly industry. Moreover, we study the application of lightweight materials for vehicles to improve mileage in the EV industry and technical problems to be solved in the future.

Comparative Evaluation of Reproducibility for Spatio-temporal Rainfall Distribution Downscaled Using Different Statistical Methods (통계적 공간상세화 기법의 시공간적 강우분포 재현성 비교평가)

  • Jung, Imgook;Hwang, Syewoon;Cho, Jaepil
    • Journal of The Korean Society of Agricultural Engineers
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    • v.65 no.1
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    • pp.1-13
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    • 2023
  • Various techniques for bias correction and statistical downscaling have been developed to overcome the limitations related to the spatial and temporal resolution and error of climate change scenario data required in various applied research fields including agriculture and water resources. In this study, the characteristics of three different statistical dowscaling methods (i.e., SQM, SDQDM, and BCSA) provided by AIMS were summarized, and climate change scenarios produced by applying each method were comparatively evaluated. In order to compare the average rainfall characteristics of the past period, an index representing the average rainfall characteristics was used, and the reproducibility of extreme weather conditions was evaluated through the abnormal climate-related index. The reproducibility comparison of spatial distribution and variability was compared through variogram and pattern identification of spatial distribution using the average value of the index of the past period. For temporal reproducibility comparison, the raw data and each detailing technique were compared using the transition probability. The results of the study are presented by quantitatively evaluating the strengths and weaknesses of each method. Through comparison of statistical techniques, we expect that the strengths and weaknesses of each detailing technique can be represented, and the most appropriate statistical detailing technique can be advised for the relevant research.

Effects of In Situ YAG on Properties of the Pressurless Annealed Sic-$TiB_2$ Electroconductive Ceramic Composites (무가압 어닐드한 Sic-$TiB_2$ 전도성 복합체의 특성에 미치는 In Situ YAG의 영향)

  • Shin, Yong-Deok;Ju, Jin-Young;Ko, Tae-Hun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.5
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    • pp.808-815
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    • 2008
  • The composites were fabricated 61[vol.%] ${\beta}$-SiC and 39[vol.%] $TiB_2$ powders with the liquid forming additives of 8, 12, 16[wt%] $Al_2O_3+Y_2O_3$ as a sintering aid by pressureless annealing at 1650[$^{\circ}C$] for 4 hours. The present study investigated the influence of the content of $Al_2O_3+Y_2O_3$ sintering additives on the microstructure, mechanical and electrical properties of the pressureless annealed SiC-$TiB_2$ electroconductive ceramic composites. Reactions between SiC and transition metal $TiB_2$ were not observed in the microstructure and the phase analysis of the pressureless annealed SiC-$TiB_2$ electroconductive ceramic composites. Phase analysis of SiC-$TiB_2$ composites by XRD revealed mostly of ${\alpha}$-SiC(6H), ${\beta}$-SiC(3C), $TiB_2$, and In Situ YAG($Al_2Y_3O_{12}$). The relative density of SiC-$TiB_2$ composites was lowered due to gaseous products of the result of reaction between SiC and $Al_2O_3+Y_2O_3$. There is another reason which pressureless annealed temperature 1650[$^{\circ}C$] is lower $300{\sim}450[^{\circ}C]$ than applied pressure sintering temperature $1950{\sim}2100[^{\circ}C]$. The relative density, the flexural strength, the Young's modulus and the Vicker's hardness showed the highest value of 82.29[%], 189.5[Mpa], 54.60[Gpa] and 2.84[Gpa] for SiC-$TiB_2$ composites added with 16[wt%] $Al_2O_3+Y_2O_3$ additives at room temperature. Abnormal grain growth takes place during phase transformation from ${\beta}$-SiC into ${\alpha}$-SiC was correlated with In Situ YAG phase by reaction between $Al_2O_3$ and $Y_2O_3$ additive during sintering. The electrical resistivity showed the lowest value of 0.0117[${\Omega}{\cdot}cm$] for 16[wt%] $Al_2O_3+Y_2O_3$ additives at 25[$^{\circ}C$]. The electrical resistivity was all negative temperature coefficient resistance (NTCR) in the temperature ranges from $25^{\circ}C$ to 700[$^{\circ}C$]. The resistance temperature coefficient of composite showed the lowest value of $-2.3{\times}10^{-3}[^{\circ}C]^{-1}$ for 16[wt%] additives in the temperature ranges from 25[$^{\circ}C$] to 100[$^{\circ}C$].