• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.651-655
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• 2000

Polymerase chain reaction (PCR) was used to specifically detect Phytophthora infestans by analyzing the sequences of the ribosomal internal transcribed spacer regions (ITS) in the rDNA of the Phytophthora species. Based on the sequence data, PISP-1 together with the ITS3 primer were used to detect p. infestans. A single ca. 450 bp segment was observed in P. infestans, but not in the other fungal or bacterial isolates. Two factors, the annealing temperature and template DNA quantity, were investigated to determine the optimal conditions. Using these species-specific primers, a unique band was obtained within annealing temperatures of $55^{\circ}C$-$61^{\circ}C$ and template DNA levels of 10 pg-100 ng.

• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.183-188
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• 1999

For two engine design parameters; compression ratio and intake swirl ratio, measurement of concentrations of hydrocarbon species has been made as a function of various air-fuel ratio in order to investigate the ozone formation of HC emissions from LPG fuel. Higher compression ratio gave lower SR values due to larger aIkan species and higher BSR values because of larger NMHC generation. Swirl ratio did not affect HC emissions and ozone formation. For ${\lambda}=1.1{\sim}1.2$, higher SR values resulted from the species of aIken which has higher MIRs were highly produced. Leaner mixture showed lower SR values due to the increase of the aIkan which has a lower MIR.

• Journal of Microbiology
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• v.44 no.4
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• pp.461-465
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• 2006

The occurrence of thioredoxin reductase (NAD(P)H: oxidized-thioredoxin reductase, EC 1.6.4.5, TrxR) in five mesophilic species of Deinococcus was investigated by PAGE. Each species possessed a unique TrxR pattern, for example, a single TrxR characterized D. radiopugnans while multiple forms of TrxR occurred in other Deinococcal spp. Most of TrxRs occurring in Deinococcus showed dual cofactor specificity, active with either NADH or NADPH, although the NADPH specific-TrxR was observed in D. radiophilus and D. proteolytic us.

• Journal of Plant Biology
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• v.27 no.3
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• pp.107-127
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• 1984

An anthecological study of Tilia in Korea was undertaken for six native and one introduced species. Flowers are protoandrous with anther and stigma opening during the day-time in section(sect) Anastraea and the night-time in sect Astrophilyra. Nectar production was coincided with anther and stigma opening. It is revealed that the primary role of floral bracts was attracting pollinators especially in sect Astrophilyra. The peak of stamen and stigma function, and the production of nectar and odor were closely related with pollinator attraction. Forthy-three species of insects in 30 families were identified for the pollination studies; bees were the most commonly observed visitors in sect Anastraea, while moths were the primary visitors in sect Astrophilyra. Pollination study indicate that it is section specific. But within a section, pollination is not species specific thus interspecific hybridization occurs.

• The Plant Pathology Journal
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• v.18 no.6
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• pp.338-341
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• 2002

The potato scab is caused by several species of Streptomyces. Among these species, only pathogenic strains were found to produce thaxtomin A characterized by necrotic bioassay and HPLC. In this study, identification of the pathogenic strains of Streptomyces was performed through the polymerase chain reaction (PCR) by using specific pathogenicity primer sets derived from the nec1 gene sequences of Streptomyces scabies. The expected PCR products were obtained approximately 580 bp and confirmed by sequencing. This PCR technique can be used effectively to identify the pathogenic Streptomyces species, that cause scab on potato tubers.

• Journal of the Korean Wood Science and Technology
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• v.26 no.4
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• pp.34-42
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• 1998

Three hardwood (ash, alder and black locust) and three softwood (Japanese red pine, radiata pine and Western hemlock) specimens were dried in microwave(MlW) oven and their drying rates were obtained. Their specific permeabilities were also measured by using a modified liquid permeability measuring device. The correlation between the M/W drying rates and permeabilities of six species were statistically analyzed. It was revealed that within a species there is a logarithmic relationship between the M/W drying rates and average moisture contents and that among species there is a linear relationship between the M/W maximum drying rates and the average specific permeabilities. A exception was Western hemlock, which was of low permeability and of high drying rate. A Me-time equation, which showed a good agreement with the actual data, was derived. Thus using this equation the moisture contents of wood and the drying end points of M/W drying could be predicted. Infrared images of the thermal distribution in wood were illustrated.

• Animal Systematics, Evolution and Diversity
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• v.38 no.4
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• pp.274-278
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• 2022

One marine ciliate, Diophrys quadrinucleata Zhang et al., 2020 was newly recorded from South Korea in this study. We provided morphological diagnosis and images of the Korean D. quadrinucleata population. We determined the small subunit ribosomal DNA (SSU rDNA) and cytochrome oxidase subunit I (CO1) sequence data of D. quadrinucleata, and then the sequences were compared with other Diophrys species. Intra-specific variation between the Korean and type (Chinese) populations was identical in the SSU rDNA, while the inter-specific variations between seven Diophrys species were 0.3-3.8% in the SSU rDNA and 12.6-18.2% in the CO1. In this study, we obtained 18S and CO1 data from species with identified morphology. As the importance of securing 18S and CO1 based on morphology increases in current studies, this study will contribute to ciliate studies.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.108-119
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• 1996

Several parameters of hydraulic architecture relating to hydraulic conductance in xylem vessels were investigated in the current-year shoots of six species of deciduous oak trees. The above parameters were also investigated in the sprouts of Quercus mongolica and Q. variabilis, as well as in the seedlings of Q. mongolica and Q. acutissima. The values of specific conductivity, leaf specific conductivity and Hagen-Poiseuille's relative hydraulic conductivity relating to vessel diameter of Q. dentata were the highest in all of the species studied. The above values of most of the species studied were higher in May-June than in September-October because of increasing the vessel embolism by cavitation and so on through the growing season. The estimated values of relative hydraulic conductivity of vessel by Hagen-Poiseuille's empirical equation and the real values of hydraulic conductivity presented positive relationships in most of the species studied. Huber value and leaf specific conductity using leaf area or leaf weight generally exhibited similar patterns each other even if having some exceptions. The hydraulic conductances of sprouting shoots were much better than those of normal growing shoots in Q. rnongolica and Q. variabilis. The specific conductivity and leaf specific conductivity were rapidly decreased by the vessel embolism through cavitating just after cutting the shoots in Q. mongolica and Q. acutissima seedlings. Diurnal changes of the conductivities in the seedlings of Q. mongolica and Q. acutissima presented the possibility of their self-controlling of conductance by active moisture absorption under mild water stress. Specific conductivity and leaf specific conductivity, and so on of Q. acutissima seedlings subjected to periodical moisture stress or not have decreased through the growing season, but the influences of moisture stress to the conductance were not proved definitely because of influencing similarly and simultaneously to the development of xylem and leaf having inverse relation in the influences. The values of conductivities were higher generally in middle or upper parts of stems than root collar in the seedlings.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.4
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• pp.568-572
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• 2015

Acetes chinensis is an economically important shrimp that belongs to the Sergestidae family; following fermentation, A. chinensis' economic value, however, is low in China, and much of the catch in China is exported to Korea at a low price, thus leading to potential false labeling. For this reason, we developed a simple method to identify A. chinensis' origin using allele-specific polymerase chain reaction (PCR). Ten single nucleotide polymorphisms (SNPs) were identified from partial (i.e., 570 bp) DNA sequence analysis of the mitochondrial 16s rRNA gene in 96 Korean and 96 Chinese individual shrimp. Among 10 SNP sites, four sites were observed in populations from both countries, and two sites located in the middle with SNP sites at their 3'-ends were used to design allele-specific primers. Among the eight internal primers, the C220F primer specific to the Chinese A. chinensis population amplified a DNA fragment of 364 bp only from that population. We were able to identify the A. chinensis population origin with 100% accuracy using multiplex PCR performed with two external primers and C220F primers. These results show that the 16S rRNA gene that is generally used for the identification of species can be used for the identification of the origin within species of A. chinensis, which is an important finding for the fair trade of the species between Korea and China.

• Parasites, Hosts and Diseases
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• v.60 no.2
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• pp.143-147
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• 2022

Acanthamoeba keratitis (AK) is a rare ocular disease, but it is a painful and sight-threatening infectious disease. Early diagnosis and adequate treatment are necessary to prevent serious complications. While AK is frequently diagnosis via several PCR assays or Acanthamoeba-specific antibodies, a more specific and effective diagnostic method is required. This study described the production of a polyclonal peptide antibody against the periplasmic binding protein (PBP) of A. castellanii and investigated its diagnostic potential. Western blot analysis showed that the PBP antibody specifically reacted with the cell lysates of A. castellanii. However, the PBP antibody did not interact with human corneal epithelial (HCE) cells and the other 3 major causative agents of keratitis. Immunocytochemistry (ICC) results revealed the specific detection of A. castellanii trophozoites and cysts by PBP antibodies when A. castellanii were co-cultured with HCE cells. PBP antibody specificity was further confirmed by co-culture of A. castellanii trophozoites with F. solani, S. aureus, and P. aeruginosa via ICC. The PBP antibody specifically reacted with the trophozoites and cysts of A. polyphaga, A. hatchetti, A. culbertsoni, A. royreba, and A. healyi, thus demonstrated its genus-specific nature. These results showed that the PBP polyclonal peptide antibody of A. castellanii could specifically detect several species of Acanthamoeba, contributing to the development of an effective antibody-based AK diagnostics.