• Earthquakes and Structures
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• v.14 no.1
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• pp.33-44
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• 2018

Base-isolated nuclear power plant (BI-NPP) structures are founded on expanded basemat as a flexible floating nuclear island, are still lacking the recommendation of the consideration of incoherent motion effect. The effect of incoherent earthquake motion on the seismic response of BI-NPP structure has been investigated herein. The incoherency of the ground motions is applied by using an isotropic frequency-dependent spatial correlation function to perform the conditional simulation of the reference design spectrum compatible ground motion in time domain. Time history analysis of two structural models with 486 and 5 equivalent lead plug rubber bearing (LRB) base-isolators have been done under uniform excitation and multiple point excitation. two different cases have been considered: 1) Incoherent motion generated for soft soil and 2) Incoherent motion generated for hard rock soil. The results show that the incoherent motions reduce acceleration and the lateral displacement responses and the reduction is noticeable at soft soil site and higher frequencies.

• Journal of Plant Biology
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• v.19 no.1
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• pp.14-18
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• 1976

Inhibition of flowering in Lemna perpusilla 6746 by 30 mM sucrose was reversed by the addition of acetylcholine (>$10^{-4}M) supplemented with 10^{-4}M$ ascorbic acid to 1/10-strength Hunter's growth medium. The reversible effect of acetylcholine was found to be greater at early stages of flowering than in the later period. Promotive effects of both acetylcholine ($10^{-3}M) and eserine(10^{-5}M$) on flowering in the short-day plant under various photoperiodic conditions were studied. It was indicated that the application decreased length of the critical dark period for the floral induction, and it was also shown that the endogenous status of acetylcholine was involved in the floral response which had a correlation with phytochrome. Interruption of inductive dark periods by red irradiation (1min) immediately followed by far-red light (1 min) completely inhibited flowering, while the addition of acetylcholine and eserine to the medium under the same condition slightly promoted flowering, indicating possible involvement of phytochrome system in acetylcholine activity for photoperiodic sensitivity of floral response in Lemna perpusilla 6746.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.278-284
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• 2011

The CCR4-CAF1-NOT complex-mediated degradation of mRNA is a fundamental aspect of gene regulation in eukaryotes. We herein examined the role of AtCAF1 in the innate immune and wound responses of plants. Our results showed that overexpression of AtCAF1 significantly downregulated the transcript level of EFR but not FLS2 and BRI1, as well as abolished up-regulated expression pattern of EFR in response to wounding. Consistently, Agrobacteriummediated transient expression of GUS was highly enhanced in the transgenic plants overexpressing AtCAF. Furthermore, JA responsive genes were down-regulated by overexpression of AtCAF, causing the transgenic plants overexpressing AtCAF more susceptible to necrotrophic fungal pathogen, Botrytis cinerea. These results suggest that The CCR4-CAF1-NOT complex-mediated degradation of mRNA negatively regulates wounding-mediated disease resistance in Arabidopsis thaliana.

• Molecules and Cells
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• v.38 no.7
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• pp.651-656
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• 2015

Plant growth and development are coordinately orchestrated by environmental cues and phytohormones. Light acts as a key environmental factor for fundamental plant growth and physiology through photosensory phytochromes and underlying molecular mechanisms. Although phytochromes are known to possess serine/threonine protein kinase activities, whether they trigger a signal transduction pathway via an intracellular protein kinase network remains unknown. In analyses of mitogen-activated protein kinase kinase (MAPKK, also called MKK) mutants, the mkk3 mutant has shown both a hypersensitive response in plant hormone gibberellin (GA) and a less sensitive response in red light signaling. Surprisingly, light-induced MAPK activation in wild-type (WT) seedlings and constitutive MAPK phosphorylation in dark-grown mkk3 mutant seedlings have also been found, respectively. Therefore, this study suggests that MKK3 acts in negative regulation in darkness and in light-induced MAPK activation during dark-light transition.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.338-344
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• 2003

The seismic analysis method of spent fuel storage structures for PHWR plant is introduced in comparison with the method for PWR plant. Investigating the structural characteristics of the storage structures, the former is vertically stacked fuel storage trays, while the latter is welded honeycomb type structure. However, as both structures are submerged and free standing, the analysis methods to anticipate the seismic response of both structures are complicated. For the better estimation of actual seismic response, how to model the dynamic properties and the structural behaviour is the key issue. In this paper, the overall procedures of the seismic modelling and stability check for seismic sliding and overturning of the two different storage structures are discussed in the viewpoint of analysis reliability

• 전기의세계
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• v.18 no.1
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• pp.15-23
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• 1969

A lot of recent researches have shown that a Pseudo Random Binary Signal is a quite effective test signal to measure the impulse response of a plant. Generally speaking, however, such a response itself is not satisfactory to determine the appropriate control parameters or control inputs. Here, the author intends to estimate the unknown parameters of the First Order Plant with Dead Time by means of correlation method using M-sequence signal. The time constant T and the dead time L of the plant are eatimated with one tracking loop by automatically adjusting delay time .tau. of M-sequence signal according to variations of T and L. In this paper, a three level M-sequence signal is used as a test signal in order to avoid troublesome operations to calculate partial derivatives of a given performance index with respect to the parameters which are usually required in the Model Method. Several experiments with analogue computer using low pass filters as averaging circuits showed good results as expected.

• Journal of Environmental Health Sciences
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• v.19 no.3
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• pp.64-73
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• 1993

The study was conducted to investigate the mechanism of tumor promotion as the time courses and the doses of promoter, and the effect of plant fiavonoids on the TPA-induced ODC responses. The results are summarized as follows: 1. A single, toppical application of 17 nmole of the potent tumor promoter, 12-O-tetradecanoyl phorbol-13-acetate, resulted in an induction of mouse epidermal Ornithine Decarboxylase with a peak at 5 hours after treatment and maximized 5.1 times as large as ODC activities of control. 2. Dose-response curve indicated that the tumor promotion increases proportionally between 1.7 and 170 nmole of TPA. This dose dependency relationship indicated that the ability of TPA to stimulate ODC is linked its ability to promote tumors. 3. Naturally occurring plant fiavonoids with anticarcinogenic and antipromotional activities were tested for their abilities to inhibit ODC response induced by skin tumor promoter TPA. Intra peritoneal administration of fiavonoids compounds (rutin, naphthofiavone, baicalein, quercitrin) and herbal drugs (sophorae rios, crataegi fructus, armeniacae semen) inhibited 17 nmole TPA-induced ODC activities in mouse epidermis in vivo.

• Molecules and Cells
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• v.27 no.3
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• pp.321-327
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• 2009

Voltage-dependent anion channels (VDACs) are reported to be porin-type, ${\beta}$-barrel diffusion pores. They are prominently localized in the outer mitochondrial membrane and are involved in metabolite exchange between the organelle and the cytosol. In this study, we have investigated a family of VDAC isoforms in Arabidopsis thaliana (AtVDAC). We have shown that the heterologous expression of AtVDAC proteins can functionally complement a yeast mutant lacking the endogenous mitochondrial VDAC gene. AtVDACs tagged with GFP were localized to mitochondria in both yeast and plant cells. We also looked at the response of AtVDACs to biotic and abiotic stresses and found that four AtVDAC transcripts were rapidly up-regulated in response to a bacterial pathogen.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.1
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• pp.26-31
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• 2000

This study was carried out to obtain the basic information for breeding cold-tolerant rice varieties with high yield-productivity through wide crosses between indica and japonica rice. Genetic analysis was conducted using 55 F$_1$s obtained from half-diallel crosses among eleven cultivars of various origin including indica and japonica rice. Screening for cold tolerance was done with cold-water irrigation after transplanting until ripening stage. Both general combining ability (GCA) and specific combining ability (SCA) effects were highly significant in all characters associated with dry matter accumulation at 30 and 50days after cold-water irrigation (DAC). The variance of GCA was much larger than that of SCA in plant height, shoot dry weight per plant (DWP), crop growth rate (CGR) and cold-water response index (CRI) of these characters except CRI of shoot dry weight per plant. The DWP, CGR and CRI of these characters of Gaochan 102, Tong88-7 and TR22183 were markedly higher than those of the others. GCA effects of these varieties on DWP, CGR and their CRI were also higher than those of the others, indicating that they are useful as promising parents for breeding cold-tolerant varieties. Analysis of genetic parameters for 11$\times$11 half-diallel F$_1$s revealed that inter-locus gene interaction were concerned in the expression of plant height at 50 DAC, CRI of DWP at 50 DAC, and CRI of CGR, and that intra-locus gene interaction for plant height and the other characters were partial dominance and over-dominance, respectively. Narrow-sense heritability (h$^2$$_{N}$) was the highest in plant height as 0.729, and the lowest in CRI of DWP at 30 DAC as 0.048, suggesting that selection for cold tolerance will be quite effective in case that the selection criterion is the performance itself.f.

• Journal of Ginseng Research
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• v.47 no.6
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• pp.773-783
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• 2023

Background: Gray mold, caused by Botrytis cinerea, is one of the major fungal diseases in agriculture. Biological methods are preferred over chemical fungicides to control gray mold since they are less toxic to the environment and could induce the resistance to pathogens in plants. In this work, we try to understand if ginseng defense to B. cinerea could be induced by fungal hypovirulent strain △BcSpd1. BcSpd1 encodes Zn(II)₂Cys₆ transcription factor which regulates fungal pathogenicity and we recently reported △BcSpd1 mutants reduced fungal virulence. Methods: We performed transcriptomic analysis of the host to investigate the induced defense response of ginseng treated by B. cinerea △BcSpd1. The metabolites in ginseng flavonoids pathway were determined by UPLC-ESI-MS/MS and the antifungal activates were then performed. Results: We found that △BcSpd1 enhanced the ginseng defense response when applied to healthy ginseng leaves and further changed the metabolism of flavonoids. Compared with untreated plants, the application of △BcSpd1 on ginseng leaves significantly increased the accumulation of p-coumaric acid and myricetin, which could inhibit the fungal growth. Conclusion: B. cinerea △BcSpd1 could effectively induce the medicinal plant defense and is referred to as the biological control agent in ginseng disease management.