• Title/Summary/Keyword: growth phase

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Changes in the levels of $Ca^{2+}$/calmodulin - binding proteins and glutamate decarboxylase during the growth of tobacco suspension cells (담배 배양 세포의 성장과정 중 칼슘/칼모듈린-결합단백질 및 glutamate decarboxylase의 생성변화)

  • Han, Kwang-Soo;Oh, Suk-Heung
    • Applied Biological Chemistry
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    • v.43 no.4
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    • pp.231-235
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    • 2000
  • The changes of calmodulin levels, calmodulin-binding proteins, and $Ca^{2+}$/calmodulin-dependent glutamate decarboxylase during the growth of tobacco suspension cells were investigated. Tobacco cells exhibited a typical growth curve, including an exponential growth phase between 3 and 5 days after inoculation, and an apparent stationary phase occurring after 5 day. Although slight changes were observed from sample to sample, calmodulin protein levels remained similar during the phases of culture growth. Several $Ca^{2+}-dependent$ calmodulin-binding proteins including 56, 46, 36, and 32-kDa proteins were detected in tobacco cell extracts. The 56-kDa protein was identified as glutamate decarboxylase by Western-blot analysis using an anti-GAD monoclonal antibody. The levels of GAD protein and the specific activity of GAD enzyme were highest during the middle exponential phase of the culture growth cycle. These data suggest that $Ca^{2+}$/calmodulin-dependent glutamate decarboxylase is modulated during the growth of tobacco suspension cells.

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Action Mechanism of Chamaecyparis obtusa Oil on Hair Growth

  • Park, Young-Ok;Kim, Su-Eun;Kim, Young-Chul
    • Toxicological Research
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    • v.29 no.4
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    • pp.241-247
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    • 2013
  • This study was carried out to examine the action mechanism of Chamaecyparis obtusa oil (CO) on hair growth in C57BL/6 mice. For alkaline phosphatase (ALP) and ${\gamma}$-glutamyl transpeptidase (${\gamma}$-GT) activities in the skin tissue, at week 4, the 3% minoxidil (MXD) and 3% CO treatment groups showed an ALP activity that was significantly higher by 85% (p < 0.001) and 48% (p < 0.05) and an ${\gamma}$-GT activity that was significantly higher by 294% (p < 0.01) and 254% (p < 0.05) respectively, as compared to the saline (SA) treatment group. For insulin-like growth factor-1 (IGF-1) mRNA expression in the skin tissue, at week 4, the MXD and CO groups showed a significantly higher expression by 204% (p < 0.05) and 426% (p < 0.01) respectively, as compared to the SA group. At week 4, vascular endothelial growth factor (VEGF) expression in the MXD and CO groups showed a significantly higher expression by 74% and 96% (p < 0.05) respectively, however, epidermal growth factor (EGF) expression in the MXD and CO groups showed a significantly lower expression by 66% and 61% (p < 0.05) respectively, as compared to the SA group. Stem cell factor (SCF) expression in the MXD and CO groups was observed by immunohis-tochemistry as significant in a part of the bulge around the hair follicle and in a part of the basal layer of the epidermis. Taking all the results together, on the basis of effects on ALP and ${\gamma}$-GT activity, and the expression of IGF-1, VEGF and SCF, which are related to the promotion of hair growth, it can be concluded that CO induced a proliferation and division of hair follicle cells and maintained the anagen phase. Because EGF expression was decreased significantly, CO could delay the transition to the catagen phase.

A study on the growth behavior of AlN single crystal according to the change of N2 in HVPE propcess (HVPE(Hydride Vapor Phase Epitaxy) 법을 적용한 N2 양의 변화에 따른 AlN 단결정의 성장 거동에 관한 연구)

  • Kyung-Pil Yin;Seung-Min Kang
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.34 no.2
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    • pp.61-65
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    • 2024
  • HVPE (Hydride vapor phase epitaxy) is a method of manufacturing thin films or single crystals using gaseous raw materials. This is a method that applies the principles of chemical vapor deposition to grow a single crystal of a material with low meltability or high melting point, and is one of the methods that can obtain a gallium nitride (GaN) single crystal. Recently, much research has been conducted to grow aluminum nitride (AlN) single crystals using this method, but good results have not yet been obtained. In this study, we attempted to grow AlN single crystals using the HVPE method. Nitrogen was used as a carrier gas in the growth process, and the growth results according to changes in the amount of nitrogen (N2) were examined. Changes in growth crystals as the amount of nitrogen increased were confirmed. The shape of the grown AlN single crystal was observed using an optical microscope, and the rocking curve was measured using double crystal X-ray diffractometry (DCXRD) to confirm the creation of the AlN crystal. The crystallinity of single crystals was also investigated.

Crystal growth studies of $SF_6$ clathrate hydrate ($SF_6$ 하이드레이트 결정의 성장 특성에 대한 연구)

  • Lee, Yoon-Seok;Lee, Ju-Dong;Lee, Bo-Ram;Lee, Hyun-Ju;Lee, Eun-Kyung;Kim, Soo-Min;Kim, Young-Seok;Yoon, Seog-Young;Kim, Yang-Do
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.19 no.5
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    • pp.228-236
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    • 2009
  • In this study, we investigated morphological characteristics of $SF_6$ clathrate hydrate crystals to understand its formation and growth mechanism. $SF_6$ clathrate hydrate crystals were formed in high-pressure reaction cell charged with pure water and $SF_6$ gas at constant pressure and temperature. Two-phase ($SF_6$ gas/aqueous solution) and three-phase ($SF_6$ gas/aqueous solution/$SF_6$ liquid) conditions were investigated, In both conditions, dendritic shape hydrate crystals were grown as like fibriform crystals along upward growth direction at the gas/aqueous solution interface. In the case of the reaction process of three-phase condition, when the $SF_6$ gas bubbles which were generated in $SF_6$ liquid phase due to the reduction of reaction cell pressure stuck to the gas/aqueous interfaces, the hydrate phase were appeared at the surface of the bubbles. This paper presents the detail growth characteristics of $SF_6$ hydrate crystals including crystal nucleation, migration, growth and interference.

Dietary crude protein levels during growth phase affects reproductive characteristics but not reproductive efficiency of adult male Japanese quails

  • Retes, Pamela Lacombe;Neves, Danusa Gebin das;Bernardes, Laryssa Fernanda;Alves, Victoria Veiga;Goncalves, Natalia de Castro;Lima, Diego de Rezende;Alvarenga, Renata Ribeiro;Pereira, Barbara Azevedo;Seidavi, Alireza;Zangeronimo, Marcio Gilberto
    • Animal Bioscience
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    • v.35 no.3
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    • pp.385-398
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    • 2022
  • Objective: The objective was to evaluate the influence of different dietary crude protein (CP) levels during the growth phase on reproductive characteristics and reproductive efficiency as well as the body development of adult male Japanese quail. Methods: Three hundred one-day-old male quails were distributed into five treatments with diets containing different CP levels (18%, 20%, 22%, 24%, and 26%) in a completely randomized design, with six replicates of ten birds each. The CP diets were applied only during the growth phase (1 to 35 days). At 36 days of age, the birds were transferred to 30 laying cages with three males and nine females each, and all birds received the same diet formulated to meet production-phase requirements until 96 days of age. Results: The growth rate of the birds increased linearly (p<0.01) with increasing dietary CP, but the age of maximum growth decreased (p<0.05). At growth maturity, all birds had the same body weight (p>0.05). At 35 days of age, higher weight gain was obtained (p<0.05) with diets containing 22% CP or higher. No effects on feed conversion were observed in this phase. The increase in dietary CP enhanced (p<0.01) nitrogen intake and nitrogen excretion but did not affect (p>0.05) nitrogen retention. Testis size, seminiferous tubular area, number of spermatogonia, and germinal epithelial height at 35 days of age increased linearly (p<0.05) with dietary CP, while the number of Leydig cells decreased (p<0.01). The Sertoli cell number at 60 days of age increased linearly (p<0.01) with dietary CP. Dietary CP levels did not affect cloacal gland size, foam weight, foam protein concentration, semen volume, or flock fertility at 90 days of age. Conclusion: Dietary CP concentration affected body and testicular development in male Japanese quails but did not affect reproductive efficiency.

Investigation of thermodynamic analysis in GaN thick films gtowth (GaN 후막 증착의 열역학적 해석에 관한 연구)

  • 박범진;박진호;신무환
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.8 no.3
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    • pp.388-395
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    • 1998
  • This paper reports on a thermodynamic analysis for the GaN thick film growth by vapor phase epitaxy method. The thermodynamic calculation was performed using a chemical stoichiometric algorism. The simulation variables include the growth temperature in a range 400~1500 K, the gas ratios $(GaCl_3)/(GaCl_3+NH_3)$ and $(N_2)/(GaCl_3+NH_3)$. The theoretical calculation predicts that the growth temperature of GaN be in the lower range of 450~750 K than the experimental results. The difference in the growth temperature between the simulation and the experiments indicates that the vapor phase epitaxy of GaN is kinetically limited, presumably, due to the high activation energy of thin film growth.

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Batch Time Course Behaviors of Growth and Berberine Production in Plant cell suspension Cultures of Thalictrum rugosum. (Thalictrum rugosum 식물세포배양에 있어서 시간에 따른 세포성장 및 Berberine 생산의 변화)

  • 김동일
    • KSBB Journal
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    • v.4 no.3
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    • pp.271-275
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    • 1989
  • Batch growth of plant cell suspension cultures of Thalictrum rugosum was studied to clarify the kinetic behaviors. It was found that the product formation was growth associated. The specific growth rate was $0.20-0.25\;day\;^{-1}$/TEX> at the growth phase and the FW/DCW ratio was an interesting parameter which represented the status of the cells or the status of sugar concentration. The cell yield was 0.36 g cells/g sugar. The maximum berberine level was 139 mg/L of which 120 mg/L was intracellular. In terms of the specific content of berberine, the product was 1.10% of dry cell weight. At the growth phase, the relationship between the specific growth rate and sugar concentration was described well by Monod kinetics.

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An Empirical Study on the Critical Success Factor of Technological Innovation of Small-Medium Sized enterprises by growth stages - Focusing on the Case Study (기술혁신형 중소·중견기업의 성장단계별 핵심성공요인에 관한 실증연구 - 사례연구를 중심으로)

  • Kim, Hong-Cheul;Lee, Sun-Kyu
    • Journal of Digital Convergence
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    • v.12 no.10
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    • pp.1-20
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    • 2014
  • For the most domestic small and medium sized enterprises, having found no solution of the growth. For most companies do overcome stagnation phenomenon in the growth phase, stratagy of the technical innovation is very important. In this paper, we will study the concept of growing pains and stagnation cause of domestic small and medium sized enterprises. Through this, classifying small and medium sized enterprises growing step and find out the factors that to lead technical innovation for growth. we suggest plan for stratagy to continue the growth of small enterprises to mid-sized enterprises a standpoint of the technical innovation at each growth step.

Observation of Unusual Structural Phase Transition in $VO_2$ Thin Film on GaN Substrate

  • Yang, Hyeong-U;Son, Jeong-In;Cha, Seung-Nam;Kim, Jong-Min;Gang, Dae-Jun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.573-573
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    • 2012
  • High quality $VO_2$ thin films were successfully grown on GaN substrate by optimizing oxygen partial pressure during the growth using RF sputtering technique. The $VO_2$ thin film grown on GaN substrate exhibited an unusual metal insulator transition behavior, which was known to be observed only either in doped sample or under uniaxial stress. Raman spectra also confirmed that metal insulator transition occurred from monoclinic M1 to rutile R phase via monoclinic M2 phase with increasing temperature. We believe that large lattice mismatch between $VO_2$ and GaN substrate may cause M2 phase to be thermodynamically stable. Optical transmittance and its electrical switching behavior were carefully investigated to elucidate the underlying physics of its metal insulator transition behavior. This study may lead to a unique opportunity to better understand the growth mechanism of M2 phase dominant $VO_2$ thin films.

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A Study on Phase Transformation and Microstructure Control of $Al_2O_3$ ($Al_2O_3$의 상전이 및 그에 따른 미세구조 제어에 관한 연구)

  • 신상현;오창섭;최성철
    • Journal of the Korean Ceramic Society
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    • v.34 no.6
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    • pp.553-560
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    • 1997
  • A fine $\alpha$-Al2O3 powder was prepared by sol-gel process for membrane application. And it was carried out by adding 1.5wt% $\alpha$-Al2O3 powders(mean size : 87 nm) as seeds to the prepared sols and by controlling the heating schedule (the heating rate and the soaking time) to prevent the microstructural change, which occured during $\theta$-to $\alpha$Al2O3 phase transformation. The seeded $\alpha$-Al2O3 particles acted as the heterogeneous nucleation sites for the $\alpha$-Al2O3 nucleation during the transformation of $\theta$- to $\alpha$-Al2O3 and resulted in increasing the driving force of phase transformation to activate the formation of $\alpha$-Al2O3 phase at 82$0^{\circ}C$. By $\alpha$-Al2O3 seeding and controlling of heating condition the phase transformation of $\theta$- to $\alpha$-Al2O3 was accomplished at low temperature and the grain growth process was depressed. Therefore, the unsupported membrane could be fabricated in $\alpha$-Al2O3 . The average diameter of pores in the fabricated membrane was 7 nm and the porosity was 47%.

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