• 한국지진공학회논문집
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• 제22권3호
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• pp.113-119
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• 2018

The probabilistic seismic safety assessment is one of the methodology to evaluate the seismic safety of the nuclear power plants. The site characteristics of the nuclear power plant should be reflected when evaluating the seismic safety of the nuclear power plant. The Korea seismic characteristics are strong in high frequency region and may be different from NRC Regulatory Guide 1.60, which is the design spectrum of nuclear power plants. In this study, seismic response of a nuclear power plant structure by Pohang earthquake (2017.11.15. (KST)) is investigated. The Pohang earthquake measured at the Cheongsong seismic observation station (CHS) is scaled to the peak ground acceleration (PGA) of 0.2 g and the seismic acceleration time history curve corresponding to the design spectrum is created. A nuclear power plant of the containment building and the auxiliary buildings are modeled using OPENSEES to analyze the seismic response of the Pohang earthquake. The seismic behavior of the nuclear power plant due to the Pohang earthquake is investigated. And the seismic performances of the equipment of a nuclear power plant are evaluated by the HCLPF. As a result, the seismic safety evaluation of nuclear power plants should be evaluated based on site-specific characteristics of nuclear power plants.

• Plant Biotechnology Reports
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• 제2권3호
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• pp.199-206
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• 2008

We have developed an efficient system of assessing the ability of a gene silencing cassette to silence transcripts from recalcitrant or poorly studied plant species by using a model plant as a host for the gene of interest. Tobacco plants transgenic for Lachrymatory Factor Synthase (LFS) enzyme activity from onion were first produced by introducing a CaMV 35S-onion-lfs gene construct. These plants were then subjected to a second transformation with an RNAi construct directed against the lfs gene sequence. LFS enzyme activity assay showed that the transgenic plants, containing both the lfs gene and the RNAi construct, had significantly reduced LFS activity. This observation was supported by Western analysis for the LFS protein and further validated by quantitative RT-PCR analysis that demonstrated a significant reduction in the lfs transcript level in the dual transformants. In this work, we have demonstrated that the RNAi construct is a suitable candidate for the development of a non-lachrymatory onion. Our model plant RNAi system has wide-reaching applications for assessment and targeting of plant secondary pathway genes, from poorly studied or recalcitrant plant species, that are important in the pharmacological, food and process industries.

• Parasites, Hosts and Diseases
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• 제57권1호
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• pp.17-20
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• 2019

A stray female cat of unknown age, presenting bright red watery diarrhea, was submitted to the Animal and Plant Quarantine Agency for diagnosis. In the small intestines extracted from the necropsied cat, numerous white oval-shaped organisms were firmly embedded in the mucosa and there was thickening of intestinal wall. Histopathological analysis revealed severe necrotizing enteritis, together with atrophied intestinal villi, exfoliated enterocytes, and parasitic worms. Recovered worms were identified as Pharyngostomum cordatum by morphological observation and genetic analysis. Although P. cordatum is known to occur widely in Korea, this is the first clinical description of an infection by P. cordatum causing severe feline enteritis.

• The Plant Pathology Journal
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• 제21권2호
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• pp.132-136
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• 2005

Two groups of phytoplasma were identified in chrysanthemum(Dendranthema grandiflorum) cv. Chunkwang showing distinct symptoms. Isolate Ph-ch1 showed symptoms of dwarf, witches'-broom, rosette and root death. The other isolate, Ph-ch2, revealed symptoms of dwarf, yellowing, leaf cupping, vein clearing and root death. The presence of phytoplasma structures in chrysanthemum leaf tissue was confirmed by transmission electron microscopy. The 16S rRNA gene was amplified from isolates Ph-ch1 and Ph-ch2 by PCR and cloned, and the nucleotide sequences were determined. In RFLP analysis, isolate Ph-ch2 showed profiles identical to Ph-ch1, except with restriction enzymes HhaI and MseI. The sequence data showed that isolate Ph-ch1 was most closely related to the aster yellows (AY) phytoplasma, and isolate Ph-ch2 was more closely related to stolbur phytoplasma than to AY phytoplasma. This is the first reported observation of stolbur phytoplasma in chrysanthemum species.

• 한국식물병리학회지
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• 제11권2호
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• pp.101-106
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• 1995

Deep blue fluorescence of resorcin blue-stained callose was observed only in the potato leafroll virus (PLRV)-infected potato plants, but not in other potato viruses investigated. The plant sections stained with aniline blue showed non-specific fluorescence regardless of PLRV infection, which means that aniline blue is not suitable for the staining of callose induces by PLRV infection. The fluorescence of resorcin blue-stained callose was more easily detectable than autofluorescence by a direct fluorescence detection method because of its deep blue color. The lateral branch of lower leaves was turned out to be the best material for fluorescence observation of all plant parts tested. In comparison of diagnostic efficacy of this technique to enzyme-linked immunosorbent assay (ELISA), PLRV infected potato plants showed corresponding increment of the fluorescence of resorcin blue stained callose as absorption values in ELISA increased. In the future, the criteria measuring the fluorescence objectively are thought to be determined for the practical application to the diagnosis of potato leafroll disease.

• The Plant Pathology Journal
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• 제18권3호
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• pp.126-129
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• 2002

Infected sweet potato (Ipomoea batatas) showing symptoms of sunken veins, stunting, mosaic, and mottling were collected from Gimje, Cochang, Iksan, and Haenam provinces in Korea. Electron microscopic (EM) observation of the infected tissue revealed rod and filamentous rod type virus particles of various lengths. Western blot analysis of the protein samples extracted from infected sweet potato and partially purified virus identified the isolates as Sweet potato feathery motile virus (SPFMV), Sweet potato latent virus (SwPLV), and Sweet potato chlorotic stint virus (SPCSV). Sweet potatoes were occasionally infected with more than one of these viruses. This is the first report of SwPLV and SPCSV in Korea.

• Corrosion Science and Technology
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• 제10권4호
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• pp.151-155
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• 2011

The iron oxide particles could be resulted from the corrosion of the circulating water system of a power plant. Because it may be one of the trouble materials which affect the power generation efficiency due to the deposition on steam generator tube and turbine blade, the continuous observation of its concentration is very important. The laser induced break-down detection (LIBD) technology was applied to monitor continuously the concentration of corrosion products with the detection limit of ppb level. The measurement system consists of a Nd:YAG pulsed laser, a polarizing beam splitter, a flow-type sample cell, an acoustic emission sensor, a high speed data acquisition board, a personal computer, etc.. The performance test results confirmed that this technology can be effective to monitor the corrosion product concentration of the circulating water system of a power plant.

• Mycobiology
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• 제42권4호
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• pp.409-411
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• 2014

In March 2014, a kohlrabi stem rot sample was collected from the cold storage room of Daegwallyong Horticultural Cooperative, Korea. White and fuzzy mycelial growth was observed on the stem, symptomatic of stem rot disease. The pathogen was isolated from the infected stem and cultured on potato dextrose agar for further fungal morphological observation and to confirm its pathogenicity, according to Koch's postulates. Morphological data, pathogenicity test results, and rDNA sequences of internal transcribed spacer regions (ITS 1 and 4) showed that the postharvest stem rot of kohlrabi was caused by Sclerotinia sclerotiorum. This is the first report of postharvest stem rot of kohlrabi in Korea.

• Journal of Plant Biology
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• 제11권1호
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• pp.27-32
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• 1968

In the present experiment as a basic study for establishing a hybrid seed orchard, an observation was made on the survivability of grafts using Pinus rigida as the stock and its hybrids as the sciion, and on the shape and germination of pollen collected from grafted plants. The results are summarized as follows: 1. The hybrid scion of P. rigida.taeda or $P. rigida{\times}(P. rigida.taeda)$ grafted into P. rigida stock showed lower survivability than the homoplastic graftings of P. rigida. 2. Five among the eight eleven-year old scions homoplastically grafted into two-year old stock for the staminate strobile one year after their grafting. 3. There was no difference in the size and germination ability between the pollen collected from homoplastically grafted plant and from the normal one. 4. The pollen collected from the grafted plant is thought to be usable for the control pollination as the germination of such pollen was considerably good.

• Environmental Analysis Health and Toxicology
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• 제29권
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• pp.14.1-14.8
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• 2014

Objectives Some plants were placed in indoor locations frequented by asthmatics in order to evaluate the quality of indoor air and examine the health benefits to asthmatics. Methods The present study classified the participants into two groups: households of continuation and households of withdrawal by a quasi-experimental design. The households of continuation spent the two observation terms with indoor plants, whereas the households of withdrawal passed the former observation terms with indoor plants and went through the latter observation term without any indoor plants. Results The household of continuation showed a continual decrease in the indoor concentrations of volatile organic compounds (VOCs) during the entire observation period, but the household of withdrawal performed an increase in the indoor concentrations of VOCs, except formaldehyde and toluene during the latter observation term after the decrease during the former observation term. Peak expiratory flow rate (PEFR) increased in the households of continuation with the value of 13.9 L/min in the morning and 20.6 L/min in the evening, but decreased in the households of withdrawal with the value of -24.7 L/min in the morning and -30.2 L/min in the evening in the first experimental season. All of the households exhibited a decrease in the value of PEFR in the second experimental season. Conclusions Limitations to the generalizability of findings regarding the presence of plants indoors can be seen as a more general expression of such a benefit of human-environment relations.