• 제목/요약/키워드: Order of growth

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Efficient Phosphinothricin Mediated Selection of Callus Derived from Brachypodium Mature Seed

  • Jeon, Woong Bae;Lee, Man Bo;Kim, Dae Yeon;Hong, Min Jeong;Lee, Yong Jin;Seo, Yong Weon
    • 한국육종학회지
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    • 제42권4호
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    • pp.351-356
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    • 2010
  • Brachypodium distachyon is rapidly emerged in biological study and has been currently used as a model system for genetics and functional studies for crop improvement and biofuel production. Phosphinothricin (PPT) has been widely used as a selectable agent, which raises ammonium content and induces toxicity in non-transformed plant cells. However PPT selection is not much effective on Brachypodium callus consequently reducing transformation efficiency. In order to identify the efficient conditions of PPT selection, calli obtained from mature seeds of Brachypodium (PI 254867) were cultured on the callus inducing medium (CIM) or regeneration medium (ReM) containing serial dilutions of the PPT (0, 2, 5, 10, and 15 mg/l) in dark or light condition. Callus growth and ammonium content of each treatment were measured 2 weeks after the treatment. Although callus growth and ammonium content did not show much difference in CIM, slow callus growth and increased ammonium accumulation were found in ReM. No significant difference of ammonium accumulation in response to PPT was found between dark and light conditions. In order to identify major factors affecting increased ammonium accumulation, callus was cultured on the media in combined with phytohormones (2,4-D or kinetin) and carbon sources (sucrose or maltose) containing with PPT (5 mg/l). The highest ammonium content in callus was found in the kinetin and maltose media.

젖산균과 비피더스균에 의한 Escherichia coli O157:H7과 Salmonella typhimurium의 생장억제 (Growth Inhibition of E. coli O157:H7 and Salmonella typhimurium by Lactic Acid Bacteria and Bifidobacteria)

  • 김현욱;안영태;신필기
    • 한국식품위생안전성학회지
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    • 제12권3호
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    • pp.181-187
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    • 1997
  • Lactobacillus acidophilus NCFM, Lactobacillus casei YIT 9018, Bifidobacterium longum 8001, and Bifidobacterium longum 8025 at the level of 106 cfu/$m\ell$ were cultured with 104 cfu/$m\ell$ of Escherichia coli O157:H7 KSC 109 or Salmonella typhimurium ATCC14028, in order to verify the effects of lactic acid bacteria and bifidobacteria on the growth of the pathogens. In the mixed culture of lactic acid bacteria with E. coli O157:H7 KSC 109, Growth inhibition and atypical microcolonies of E. coli O157:H7 KSC 109 were observed. The pathogens inoculated grew for 5 hors (pH 5.3), by the time L. acidophilus NCFM reached the exponential growth phase, and then the surviving pathogens were decreased to 101 cfu/$m\ell$ after 35 hours. When L. caseiYIT 9018 was grown with the pathogens, they grew for 10 hours (pH 4.6), by the time L. casei YIT 9018 reached the end of exponential growth phase, and then the surviving pathogens were decreased drastically. Up to the stationary growth phase of lactic acid bacteria, L. acidophilus NCFM exhibited stronger inhibition against the pathogens than L. casei YIT 9018 did, which might be attributed to its faster growth. Likewise bifidobacteria inhibited the growth of the pathogens tested, bifidobaceria was weaker in the inhibitory activity than lactic acid bacteria. When Bifidobacterium longum 8001 was cultured with the pathogens, E. coli O157:H7 KSC 109 was gradually ingibited at the stationary growth phase of bifidobacteria, atypical microcolonies were formed on Levine EMB medium after 48 hours, and Salmonella grew up to 106 dfu/$m\ell$, then was drastically ingibited at the exponential growth phage of Bifidobacterium longum 8001. But when Bifidobacteriuam longum 8025 was cultured with the pathogens, the pathogens grew to the same level of Bifidobacteriuam longum 8025 was cultured with the pathogens, the pathogens grew to the same lever of Bifidobacteriuam longum 8025 after 10 hours, then the surviving pathogens were decreased drastically.

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상피세포성장인자를 함유한 동결건조-재분산 리포좀의 입도분포 및 봉입률 (Size Distribution Characteristics and Entrapment Efficiency of Dried-Reconstituted Liposomes Containing Epidermal Growth Factor)

  • 김희준;유성운;최영욱
    • 약학회지
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    • 제40권6호
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    • pp.646-652
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    • 1996
  • Epidermal Growth Factor (EGF), discovered by Stanley Cohen in 1960, has a potential healing effect for wounds and bums. Considering wound care, in order to avoid physical stress at the wound surface and efficiently apply EGF, the need for viscous spraying solutions was essential. Viscous spraying solutions containing EGF were prepared by utilizing viscosity-building polymer, poloxamer 407, and by introducing liposome systems. On the other hand, EGF is purified on reverse HPLC gradient program with the mobile solvent of acetonitrile. It is necessary to observe liposomal EGF changes as the acetonitrile contents varied in order to introduce liposome systems at the step of EGF solution (at the time of EGF purifying). By evaluating the size distribution and entrapment efficiency of EGF liposome, it was possible to detemine the limit contents of acetonitrile and establish the optimal conditions for solution formulations. It has been revealed that, as the acetonitrile content increases, mean diameter of EGF liposomes increased and the width of size distribution tends to decrease. The limit contents of acetonitrile were 10%, since there was little difference to the acetonitrile free liposomes.

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토끼에서 유산 발효유제품 급여에 의한 Escherichia coli O157:H7 및 Salmonella typhimurium의 증균억제효과 (Growth Ingibiton Effect of E. coli O157:H7 and Salmonella typhimurium by Lactic Fermented Milk Products Administrated Orally in Rabbit)

  • 신광순;김용환;손원근;석주명;김상현
    • 한국식품위생안전성학회지
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    • 제12권3호
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    • pp.188-194
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    • 1997
  • The growth inhibition effect of Orally administrated yogurt ACE and Metchnikoffupon E. coli O157:H7 and S. typhimurium inoculated into gastric lumen of rabbits was in vestigated. The rabbits challenged with each 1 $m\ell$ of suspension containing 108 CFU/$m\ell$ of the pathogens were divided into 4 groups by the interval of yogurt administration: A group; preadministrated 7 days before inoculation of the pathogens and fed daily; B group; administrated daily after inocjlation of the pathogens, C group; administrated every 3 days after inoculation of the pathogens; Control group, not fed after inoculation of the pathogens. Each 3 $m\ell$ of yogurt containing 109 CFU/$m\ell$ was orally administrated into rabbits. All yogurt administrated groups (A, B, c) chowed growth ingibition effect on E. coli O157:H7 in one day after inoculation of the pathogen by the level of 0.8~1.0 log CFU/g, compared with the result differences between the control group and the yogurt administrated groups. In the control group after 5 days of inoculation, the number of colonized pathogens was 105~106 CFU/g, whereas 103~104 CFU/g was detected in the yogurt administrated groups. After 10 days of inoculation, the viable pathogen number per gram (g) of the rabbit feces was 103 CFU/g in the control group, whereas the number below 101 CFU/g was detected in the group A, and 102 CFU/g in the control group, B and C. The growth inhibition effect of yogurt administration on E. coli O157:H7 was highly increased in the order of A, B, and C group. The same effect on S. typhimurium was observed at the level of 2 log CFU/g in the Metchnikoff yogurt administrated groups, compared with the control group result in one day after inoculation of the pathogen. In 7 days after inoculation of the pathogen, the viable number was increasingly decreased, and finally after 15 days no viable cell of S. typhimurium was discharged into the fecal samples in the group A, and the mean level of 10* CFU/g was detected in the group B, but there was no growth inhibition effect in the group C. The growth inhibition effect on S. typhimurium was observed at the same level of viable cell number between the yogurt ACE administrated groups and the control group in 5 days after inoculation. But, after 10 days of inoclation the viable cell number was started to decrease, and the viable cell of S. typhimurium was not discharged from rabbit intestinal contents after 15 days of inoculation in the yogurt ACE administrated groups. In such a case that yogurt was administrated in order to prevent the pathogens, pre-administration on a daily basis one week before inoculation of the pathogens exerted considerable effect in growth inhibition. In comparison with two kinds of yogurt tested in this study, the growth inhibition effect on two kinds of pathogens was observed more highly in the Metchnikoff administated group than the ACE administrated group.

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환경조건에 따른 Aphanizomenon flos-aquae (Cyanophyceae) 균주의 성장 반응 및 독소 생성 (Response of Growth and Toxigenicity to Varying Temperature and Nutrient Conditions in Aphanizomenon flos-aquae (Cyanophyceae))

  • 류희성;신라영;이정호
    • 한국물환경학회지
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    • 제33권5호
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    • pp.538-545
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    • 2017
  • The purpose of this study is to investigate growth response and toxigenicity under various temperature and nutritional conditions, in order to understand the physioecological characteristics of Aphanizomenon flos-aquae, which is a bloom-forming cyanobacterium in the Nakdong River. The strain was inoculated into media under combinations of four temperatures (4, 12, 21, $30^{\circ}C$) and three nutrients (modified CB medium, P-depleted CB medium, N-depleted CB medium) for 28 days. The algae-inhibition tests were performed to assess the potential allelopathic effects of the strains' filtrates on the growth of four algae strains (Microcystis aeruginosa, Aulacoseria ambigua f. spiralis, Aphanizomenon flos-aquae, Scenedesmus obliquus). Toxin production of a strain was measured by Enzyme-Linked ImmunoSolbent Assay (ELISA). The optimal growth temperature (Topt) of strains was $19.9^{\circ}C$ ($18.3-21.2^{\circ}C$), and the temperature range for growth was from $-0.3^{\circ}C$ to $34.3^{\circ}C$. Specific growth rate (${\mu}$) in modified CB medium varied from 0.10 to $0.16day^{-1}$, and the maximum growth rate (${\mu}_{max}$) was $0.17day^{-1}$. Although growth curves under N-existed and N-depleted conditions were almost the same, growth under N-depleted condition was relatively slowed (${\mu}=0.09$ to $0.14day^{-1}$), with a decreased maximum cell density. However, growth under the P-depleted condition was restricted for all temperatures, Two stains of Aphanizomenon flos-aquae were confirmed as not producing toxins, because saxitoxin and cylindrospermopsin were not detected by ELISA. The exudates or filtrates from the Aphanizomenon flos-aquae (DGUC003) resulted in significant inhibition of algal growth on the Aulacoseira ambigua f. spiralis (DGUD001) and Aphanizomenon flos-aquae (DGUC001) (p < 0.01).

열증착방법에 의해 제조된 Si(100)/X(500$\AA$)/Zn(1000$\AA$) 이중박막 성장에 관한 연구 (A Study on the growth of Si(001)/X(500$\AA$)/Zn(1000$\AA$) double layers deposited by thermal evaporation process.)

  • 신동원;정순종;이동윤;민복기;정원섭;송재성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.1026-1029
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    • 2001
  • Zinc films have been deposited onto various buffer layers, Al, Al-Cu, Ag and Ag-Al, by vacuum evaporation method in order to investigate the film microstructure and its consequence on the film growth. Zn films were grown onto Al buffer layers with faster rates than on Ag buffer layers, because of the presence of preferred growth orientation. Especially, in the Zn film formation on the Ag layers, intermetallic compounds AgZn was formed to cause the different growth orientation from Zn film obtained on the Al layers.

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Urban Growth Monitoring using Multi-temporal Satellite Images and Geographic Information

  • Lee, Kwang-Jae;Kim, Youn-Soo;Kim, Byung-Kyo
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.470-472
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    • 2003
  • The primary goal in this paper is to analyze urban growth patterns using multi-temporal remote sensing images and geographic information data. In order to accomplish this purpose, firstly data pre-processing is carried out, and then land-use maps are generated with ancillary data source by heads-up on-screen digitizing. Lastly, using the results of the previous stages, the patterns of land-use and urban changes are monitored by the proposed scheme. In this research, using the multi-temporal images and geographic information data, monitoring of urban growth was carried out with the application of urban land-use changes.

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Estimation of Covariance Functions for Growth of Angora Goats

  • Liu, Wenzhong;Zhang, Yuan;Zhou, Zhongxiao
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권7호
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    • pp.931-936
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    • 2009
  • Body weights of 862 Angora goats between birth and 36 months of age, recorded on a semiyearly basis from 1988 to 2000, were used to estimate genetic, permanent environmental and phenotypic covariance functions. These functions were estimated by fitting a random regression model with 6th order polynomial for direct additive genetic and animal permanent environmental effects and 4th and 5th order polynomial for maternal genetic and permanent environmental effects, respectively. A phenotypic covariance function was estimated by modelling overall animal and maternal effects. The results showed that the most variable coefficient was the intercept for both direct and maternal additive genetic effects. The direct additive genetic (co)variances increased with age and reached a maximum at about 30 months, whereas the maternal additive genetic (co)variances increased rapidly from birth and reached a maximum at weaning, and then decreased with age. Animal permanent environmental (co)variances increased with age from birth to 30 months with lower rate before 12 months and higher rate between 12 and 30 months. Maternal permanent environmental (co)variances changed little before 6 months but then increased slowly and reached a maximum at about 30 months. These results suggested that the contribution of maternal additive genetic and permanent environmental effects to growth variation differed from those of direct additive genetic and animal permanent environmental effects not only in expression time, but also in action magnitude. The phenotypic (co)variance estimates increased with age from birth to 36 months of age.

Mutagenesis of Streptomyces kasugaensis for Kasugamycin Production

  • Cho, Hoon;Choi, Du-Bok;Lim, Chae-Kyu
    • 환경위생공학
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    • 제23권4호
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    • pp.23-29
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    • 2008
  • This study was performed to develop mutant strain using a combination of UV irradiation procedures with protoplast mutagenesis in order to achieve an effective kasugamycin production from Streptomyceskasugaensis. Whenlessthan 1.0g/lof Linoleic acid was used, the cell growth was not inhibited. On the other hand, the cell growth was greatly inhibited when more than 1.6 g/l of linoleic acid was used. Among the various mutant strains, SK-12 was obtained in medium containing 1.6g/l of linoleic acid, showing the highest rate of both cell growth and kasugamycin production. In order to compare kasugamycin production with the SK-12 and the parent strain using soybean oil, cultures were performed in a flask. The production of kasugamycin was increased with the increase time. The maximum kasugamycin concentration was 1.2g/l after 6 days of culture. The product yield from soybean oil was 0.05g/l/g consumed carbon source, which was roughly 5.0 fold higher than the parent strain. These results show that it was effective method for obtaining a mutant resistant to linoleic acid for the effective production of kasugamycin from soybean oil.

Forecasting the Environmental Change of Technological Innovation System in South Korea in the COVID-19 Era

  • Kim, Youbean;Park, Soyeon;Kwon, Ki-Seok
    • Asian Journal of Innovation and Policy
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    • 제9권2호
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    • pp.133-144
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    • 2020
  • Korean economy has experienced a very rapid growth largely due to the change of the innovation system since the last half century. The recent outbreak of COVID-19 impacts the global economy as well as Korea's innovation system. In order to understand the influence of the shock to the Korean technological system, we have forecast the future of the system combining qualitative and quantitative techniques such as expert panel, cross impact analysis, and scenario planning. According to the results, we have identified 39 driving forces influencing the change of Korea's technological innovation system. Four scenarios have been suggested based on the predetermined factors and core uncertainties. In other words, uncertainties of emergence of the regions and global value chains generate four scenarios: regional growth, unstable hope, returning to the past, and regional conflicts. The 'regional growth' scenario is regarded as the most preferable, whereas the 'regional conflicts' scenario is unavoidable. In conclusion, we put forward some policy implications to boost the regional innovation system by exploiting the weakened global value chains in order to move on to the most preferable scenario away from the return to the past regime.