• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.522-530
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• 2018

Brachypodium distachyon has been developed as a monocot model plant for temperate grasses and bioenergy crops. Although B. distachyon research is moving forward rapidly, the study of photoresponses has not been explored. To extend our knowledge of responses to light in monocots, we performed photoresponse analysis of B. distachyon using two inbred lines, Bd21 and Bd21-3. In this study, we first compared growing phenotypes between the two lines and investigated coleoptile and primary leaf growths under dark, far-red, red, and white light conditions. The results showed that the growth of the two lines were similar until tillering stage, but other developmental stages from heading to senescence were much delayed in Bd21-3, which resulted in increased height and tiller numbers. Under different light conditions, primary leaf lengths were kept increasing during the growth period, whereas the coleoptile extension was inhibited 4 to 7 days after growth depending on the light conditions applied. These results suggest that the responses to light in B. distachyon can be examined by measuring coleoptile lengths approximately 7 days after seedling growth. Moreover, we selected light-responsive genes known in Arabidopsis thaliana, such as chlorophyll A/B binding protein (CAB), light-harvesting chlorophyll binding protein (Lhcb) and chalcone synthase (CHS), and confirmed their light-induced gene expression in B. distachyon. Therefore, the present study suggests that the inhibition of coleoptile growth can be used as the parameter to analyze photoresponses in the monocot model plant, and also provide the reference genes whose expression is induced by far-red and red light treatment.

• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.473-480
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• 2008

We have investigated the optimal growth conditions of carbon nanotubes (CNTs) using the chemical vapor deposition and the Ni nanoparticle arrays. The diameter of the CNT is shown to be controlled down to below 20 nm by changing the size of Ni particle. The position and size of Ni particles are controlled continuously by using wafer-scale compatible methods such as lithography, ion-milling, and chemical etching. Using optimal growth conditions of temperature, carbon feedstock, and carrier gases, we have demonstrated that an individual CNT can be grown from each Ni nanoparticle with almost 100% probability over wide area of $SiO_2/Si$ wafer. The position, diameter, and wall thickness of the CNT are shown to be controlled by adjusting the growth conditions.

• Nuclear Engineering and Technology
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• v.48 no.4
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• pp.859-869
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• 2016

Component-scale modeling of boiling is predominantly based on the Eulerian-Eulerian two-fluid approach. Within this framework, wall boiling is accounted for via the Rensselaer Polytechnic Institute (RPI) model and, within this model, the bubble is characterized using three main parameters: departure diameter (D), nucleation site density (N), and departure frequency (f). Typically, the magnitudes of these three parameters are obtained from empirical correlations. However, in recent years, efforts have been directed toward mechanistic modeling of the boiling process. Of the three parameters mentioned above, the departure diameter (D) is least affected by the intrinsic uncertainties of the nucleate boiling process. This feature, along with its prominence within the RPI boiling model, has made it the primary candidate for mechanistic modeling ventures. Mechanistic modeling of D is mostly carried out through solving of force balance equations on the bubble. Forces incorporated in these equations are formulated as functions of the radius of the bubble and have been developed for, and applied to, low-pressure conditions only. Conversely, for high-pressure conditions, no mechanistic information is available regarding the growth rates of bubbles and the forces acting on them. In this study, we use direct numerical simulation coupled with an interface tracking method to simulate bubble growth under high (up to 45 bar) pressure, to obtain the kind of mechanistic information required for an RPI-type approach. In this study, we compare the resulting bubble growth rate curves with predictions made with existing experimental data.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.146-155
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• 1983

Fundamental study was carried out to elucidate the mechanisms of biological degradation of dyestuff in environments. A few bacterial strains which were capable of degrading amarnath were obtained from soil through an extensive screening program and identified by microbiolological properties. Conditions for bacterial growth and amaranth degradation were characterized and optimized, and the degradation products were identified. The results were as follows. 1. The most active strain A12-1 to be capable of degradation of amaranth was identified as Pseudomonas sp. 2. Optimal conditions for growth of the strain A12-1 were:$35^{\circ}C$ and pH 7.5, and growth was markedly increaesd by aeration. 3. Degradation of amaranth by the strain was accessed under similiar conditions for growth, however significantly inhibited when the culture was aerated. 4. Both bacterial growth and amaranth degradation were gradually decreased with increased concentration of amaranth in the culture. 5. Reaction of the crude enzyme from the strain A12-1 was optimal at $35^{\circ}C$ and pH 7.5 for degrading amaranth. 6. Sodium naphthionate and R-amino salt were found to be the products of amaranth degradation by the strain A12-1.

• Korean Journal of Medicinal Crop Science
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• v.28 no.4
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• pp.254-259
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• 2020

Background: Centella asiatica is a well-known medicinal plant having a wound healing effect. In this study, the growth, asiaticoside content, and antioxidant components and activity were investigated in C. asiatica resources under different cultivation and irrigation conditions. Methods and Results: The cultivation and irrigation methods were divided as greenhouse and open field, and sprinkler and sub irrigation. respectively. Growth characteristics were measured in aerial parts of C. asiatica. Asiaticoside content was analyzed using high performance liquid chromatography. Total polyphenol, total flavonoid and 2,2-diphenyl-1picryl hydrazyl (DPPH) radical scavenging activity were analyzed for antioxidant activities. Growth was higher under greenhouse and sub irrigation than open field and sprinkler conditions. In the leaves, asiaticoside content was 53.45 mg/g (open field) and 34.38 mg/g (sub irrigation), total polyphenol was 41.14 mg/g (open field) and 25.73 mg/g (sub-irrigation), and total flavonoid was 27.26 mg/g (open field) and 23.72 mg/g (sub-irrigation). DPPH radical scavenging activity in the leaves was 85.97 mg·ascorbic acid equivalent (AAE)/g (open field) and 54.83 mg·AAE/g (sub irrigation). Conclusions: Asiaticoside and antioxidant components and activity were not accompanied with high yield, although high growth was observed under greenhouse conditions. Therefore, cultural requirements of C. asiatica should be sufficiently considered to suit each purpose.

• The Korean Journal of Mycology
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• v.49 no.1
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• pp.45-55
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• 2021

Artomyces microspora is a genus of coral fungi from the family Auriscalpiaceae that have sporophores which are clavarioid, profusely and pyxidately branched, and devoid of a conspicuous stipe. These fungi can be found in summer and fall. This study aimed to decipher fundamental information regarding optimal growth conditions of Artomyces microsporus mycelia, including pH, temperature, carbon sources, and nitrogen sources. Based on the assessment of colony diameter and mycelial density, the optimal culture medium, temperature, and pH for mycelial growth were found to be PDA, 25 ℃, and pH 5.0, respectively. Furthermore, the study revealed that the optimal carbon and nitrogen sources for mycelial growth were 1% soluble starch and 2% malt extract, respectively. The other suitable inorganic nitrogen sources were deemed to be 0.1% NH₄H₄PO₄ and 0.1% aspartic acid.

• Journal of the Korean Ceramic Society
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• v.46 no.3
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• pp.253-262
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• 2009

The purpose of this study is to find out optimum conditions for zinc crystalline glaze under variables of firing: maximum firing temperature, crystal growth temperature, temperature increasing speed, annealing speed, holding time at maximum temperature and holding time at crystal growth temperature. Ferro Frit3110, ZnO and Quartz were used as starting materials and tested by three component system. The best result of test was selected and extended to its vicinity as five glaze formulas. And then the specimens were experimented by variable firing conditions and analyzed by crystal appearance observation, XRD, FT-IR and Raman spectroscopy. In result, main crystal was willemite in the zinc glazes. Some gahnite was detected in specimens which were fired at $1230^{\circ}C$, $1250^{\circ}C$ and $1270^{\circ}C$, however gahnite was not identified at $1300^{\circ}C$. Optimum zinc crystalline glaze was gained by following firing condition: temperature increasing speed $5^{\circ}C$/min, holding 1 h at $1270^{\circ}C$, annealing speed $3^{\circ}C$/min till $1170^{\circ}C$, holding 2 h at $1170^{\circ}C$ then naturally annealed.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.301-309
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• 2011

The filamentous fungus Fusarium graminearum is an important cereal pathogen. Although quantitative realtime PCR (qRT-PCR) is commonly used to analyze the expression of important fungal genes, no detailed validation of reference genes for the normalization of qRT-PCR data has been performed in this fungus. Here, we evaluated 15 candidate genes as references, including those previously described as housekeeping genes and those selected from the whole transcriptome sequencing data. By a combination of three statistical algorithms (BestKeeper, geNorm, and NormFinder), the variation in the expression of these genes was assessed under different culture conditions that favored mycelial growth, sexual development, and trichothecene mycotoxin production. When favoring mycelial growth, GzFLO and GzUBH expression were most stable in complete medium. Both EF1A and GzRPS16 expression were relatively stable under all conditions on carrot agar, including mycelial growth and the subsequent perithecial induction stage. These two genes were also most stable during trichothecene production. For the combined data set, GzUBH and EF1A were selected as the most stable. Thus, these genes are suitable reference genes for accurate normalization of qRT-PCR data for gene expression analyses of F. graminearum and other related fungi.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.482-487
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• 2000

Optimization of submerged culture conditions for the production of exo-biopolymer from Paecilomyces japonica ws studied. Maltose, yeast extract, and potassium phosphate were the most suitable sources of carbon, nitrogen, and inorganic salt, respectively, for both production of the exo-biopolymer and mycelial growth. The optimal culture conditions in a flask culture were pH 5.0, $25^{\circ}C$, and 150 rpm in a medium containing (as in g/l) 30 maltose, 6 yeast extruct, 2 polypeptone, $0.5{\;}K_3HPO_4,{\;}0.2{\;}KH_2PO_4,{\;}0.2{\;}MnSO_4{\cdot}5H_2O,{\;}0.2{\;}MgSO_4{\cdot}7H_2O$. Exo-biopolymer production and mycelial growth in the above suggested medium were significantly increased in a 2.5-1 jar fermentor, where the maximum biopolymer concentration was 8 g/l. The morphological changes of the mycelium in the submerged culture were observed within pH ranges from 4.0 to 9.0; i.e., growth of the filamentous form was optimal at culture pHs of 5.0 and 6.0, whereas pellet was formed at other pHs.

• Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.133-142
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• 2007

To investigate conditions for the survival and growth of Dungeness crab zoeae in situ, spatial and monthly changes of sea surface temperature (SST), sea surface salinity (SSS), Chlorophyll ${\alpha}$ (Chl ${\alpha}$), and zooplankton biomass were measured in four transects: upper Chatham, Icy Strait, Cross Sound, and Icy Point in southeastern Alaska from May to September, 1997-2004. Monthly mean SST was coldest in May, increased throughout the summer months, and decreased in September. SST was coldest in the Cross Sound transect, intermediate in the upper Chatham and Icy Strait transects, and warmest in the Icy Point transect. SSS of northern stations in the upper Chatham and Icy Strait transects decreased throughout the summer months and increased in September, while that of other transects did not vary. Monthly mean Chl ${\alpha}$ was highest in May and decreased thereafter. Chl ${\alpha}$ in the upper Chatham and Icy Strait transects were relatively higher from May through September than those in the Cross Sound and Icy Point transects. Mean zooplankton biomass was highest in the Icy Strait transect in May and lowest in the Icy Point transect in September. This research suggests that oceanographic conditions during the season of Dungeness crab zoeae in southeastern Alaska may not constrain the survival and growth of Dungeness crab zoeae.