• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.328-333
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• 2019

The proximate composition and mineral contents of 18 subtropical fish species caught off the coast of Jeju Island, Korea were determined. The mean moisture content was highest (78.0%) in the eight species of lean fish, lowest (72.6%) in the four species of medium-fat fish, and intermediate (75.4%) in the six species of low-fat fish. The lipid content was in the order of medium-fat fish > low-fat fish > lean fish. The protein content ranged from 17.7% to 18.9%. The mean macro-mineral contents in the 18 species were 290.2 mg/100 g edible portion K, 146.6 mg P, 113.5 mg Na, 67.2 mg Ca and 38.3 mg Mg. The mean value of micro-mineral contents were 2.1 mg Fe, 1.7 mg Cu and 1.5 mg Zn. These results suggest that subtropical fish from Jeju Island are good sources of protein, lipid and minerals.

• Entomological Research
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• v.48 no.6
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• pp.505-513
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• 2018

The red imported fire ant is considered one of the most notorious invasive species because of its adverse impact on both humans and ecosystems. Public concern regarding red imported fire ants has been increasing, as they have been found seven times in South Korea. Even if red imported fire ants are not yet colonized in South Korea, a proper quarantine plan is necessary to prevent their widespread distribution. As a basis for quarantine planning, we modeled the potential distribution of the red imported fire ant under current climate conditions using six different species distribution models (SDMs) and then selected the random forest (RF) model for modeling the potential distribution under climate change. We acquired occurrence data from the Global Biodiversity Information Facility (GBIF) and bioclimatic data from WorldClim. We modeled at the global scale to project the potential distribution under the current climate and then applied models at the local scale to project the potential distribution of the red imported fire ant under climate change. Modeled results successfully represent the current distribution of red imported fire ants. The potential distribution area for red imported fire ants increased to include major harbors and airports in South Korea under the climate change scenario (RCP 8.5). Thus, we are able to provide a potential distribution of red imported fire ant that is necessary to establish a proper quarantine plan for their management to minimize adverse impacts of climate change.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.39-45
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• 2019

In 2017, as a study to discover indigenous prokaryotic species in Korea, a total of 6 bacterial strains assigned to the genus Pseudomonas were isolated from soil. From the high 16S rRNA gene sequence similarity (${\geq}99.5%$) and phylogenetic analysis with closely related species, the isolated strains were identified as independent Pseudomonas species which were unrecorded in Korea. The six Pseudomonas species were Pseudomonas mandelii, P. canadensis, P. thivervalensis, P. jessenii, P. lurida, and P. brenneri. Gram reaction, culture conditions, colony and cell morphology, basic physiological and biochemical characteristics are described in the species description section.

• Journal of Korean Society on Water Environment
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• v.27 no.3
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• pp.314-321
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• 2011

The potential effects of increased water temperature on fish assemblages and their habitats were studied in the streams of the Han River watershed when the water temperature was supposed to increase by $1^{\circ}C$, $2^{\circ}C$, and $3^{\circ}C$ in each sampling site. The percent changes in suitable habitats for each species and in species number within a site were determined, based on the estimated maximum thermal tolerances of 51 fish species whose habitats were classified into four reaches: upstream, up-/midstream, midstream, and mid-/downstream. The maximum thermal tolerance ranged between $25.0^{\circ}C$ and $31.0^{\circ}C$ and significantly increased as the habitat reaches move from upstream to mid-/downstream. With the increases in water temperature, the average suitable habitats for all 51 species were decreased by 31% ($+1^{\circ}C$), 46% ($+2^{\circ}C$), and 60% ($+3^{\circ}C$). The increased water temperature, however, did not induce significant differences in the changes in suitable habitats among four reaches within each level of temperature increase. The relative frequencies of the sampling sites classified into six levels according to the percent change in the number of species in each site were significantly different among three levels of water temperature increase, with relatively greater changes in the sites where 0~20% and 61~100% of species were affected.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.625-637
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• 2022

The southern coast of the East Sea is an important area affected by large warm currents as it connects the coastal waters of Jeju Island, the South Sea, and Dokdo. From 2017 to 2021, the average catch per unit effort (CPUE; kg/day/ship) of set net fishery at six ports in the Gyeongbuk region off the southern coast of the East Sea was the highest in Gampo, Gyeongju, and the lowest in Hupo, Uljin. Although the seasonal variation in the CPUE differed by region and year, it was generally high in autumn. In the set net fishery in Pohang from 2019 to 2021, we identified 72 species, which decreased to 56 species in 2019, 46 in 2020, and 41 in 2021. The species diversity index slightly increased over the three-year periods. We found positive correlations between the total catch (kg) of subtropical species in autumn and the water temperature at 50 m. Among the most abundant species, we found substantially positive correlations between the CPUE of Scomber japonicus, Scomberomous spp. and Carangids. We also noted positive correlations between the CPUE of Todarodes pacificus, Seriola spp. and Carangids.

• Microbiology and Biotechnology Letters
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• v.51 no.1
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• pp.93-98
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• 2023

Nuruk is a starter culture of Korea manufactured by spontaneous fermentation of grains. We isolated bacteria of the genera Bacillus and Staphylococcus, and lactic acid bacteria (LAB) from eight commercial nuruk samples collected from four districts of Korea using selective agar media and identified them based current taxonomic standards. Bacillus was detected in all samples, but Staphylococcus or LAB were not detected in three samples. In seven samples, except one sample scored the highest cell number of LAB, Bacillus and Staphylococcus were counted as the highest and the lowest numbers, respectively. Six species of Bacillus were identified, and B. subtilis, B. velezensis, and B. licheniformis were predominant species. Nine species of coagulase-negative Staphylococcus were identified, and the predominance of S. pseudoxylosus and S. saprophyticus was confirmed. Ten species of LAB including Enterococcus, Lactobacillus and close relatives, Pediococcus, and Weissella were identified. P. pentosaceus was identified as the predominant species.

• Journal of Forest and Environmental Science
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• v.39 no.1
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• pp.1-12
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• 2023

To understand the health conditions and growth patterns of forest estate for environmental resilience and climate change mitigation, assessment of structure and species diversity is paramount. This study aimed at assessing the structure, alpha, and beta diversities of tree species in three ecological zones in Taraba, Nigeria for management purposes. In recent time, no research has been reported on the structure and beta diversity of the study areas. A systematic sampling design was used for data collection. Five sample plots of 50×50 m were laid in each of the six natural forest areas. The result showed a mean DBH (42.5 cm) and a tree height (15.0 m) from the forests. The forests have a structure of an inverse "J-shape," which is typical of natural forests in the tropics. The southern Guinea savanna zone had the highest mean Shannon-Weiner diversity index (2.8). The least beta diversity index (0.02) was between Baissa and Jen Gininya forest areas. Baissa and Bakin Dutse Protected Forest Areas (PFAs) contained 76.5% of the tree species. There is a high chance of all tree species to be found in these 2 forest areas. Proximity to a location influences how similar two tree species are, according to the least beta diversity index (0.02) recorded. The Federal Government's method of management for the forest, known as Gashaka Gumti National Park, may be responsible for the high beta diversity index in the Montane ecozone. Therefore, it should be strongly encouraged to practice strict oversight of natural areas, as their contributions to reducing climate change in Taraba State, Nigeria, cannot be overstated.

• Journal of Oral Medicine and Pain
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• v.47 no.1
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• pp.10-26
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• 2022

Purpose: The purpose of this study was to investigate whether various saliva collection methods affect the observed salivary microbiome and whether microbiomes of stimulated and unstimulated saliva and plaque differ in richness and diversity. Methods: Seven sampling methods for unstimulated saliva, stimulated saliva, and plaque samples were applied to six orally and systemically healthy participants. Bacterial 16S ribosomal RNA genes of 10 major oral bacterial species, namely, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Prevotella intermedia, Prevotella nigrescens, Streptococcus mitis, Streptococcus sobrinus, and Lactobacillus casei, were analyzed by real-time polymerase chain reaction. We comprehensively examined the dependence of the amount of bacterial ribosomal DNA (rDNA), bacterial-community composition, and relative abundance of each species on sample collection methods. Results: There were significant differences in the bacterial rDNA copy number depending on the collection method in three species: F. nucleatum, P. nigrescens, and S. mitis. The species with the highest richness was S. mitis, with the range from 89.31% to 100.00%, followed by F. nucleatum, P. nigrescens, T. denticola, T. forsythia, and P. intermedia, and the sum of the proportions of the remaining five species was less than 1%. The species with the lowest observed richness was P. gingivalis (<0.1%). The Shannon diversity index was the highest in unstimulated saliva collected with a funnel (4.449). The Shannon diversity index was higher in plaque samples (3.623) than in unstimulated (3.171) and stimulated (3.129) saliva and in mouthwash saliva samples (2.061). Conclusions: The oral microbial profile of saliva samples can be affected by sample collection methods, and saliva differs from plaque in the microbiome. An easy and rapid technique for saliva collection is desirable; however, observed microbial-community composition may more accurately reflect the actual microbiome when unstimulated saliva is assayed.

• Journal of People, Plants, and Environment
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• v.22 no.6
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• pp.575-582
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• 2019

Moss is used as an important material in indoor landscaping as well as outdoor landscaping. Moss is vivid green during growth and excellent in ornamental value. But when temperature drops, moss stops growth, turns brown or loses its ornamental value. In the present experiment, for the purpose of classifying native mosses according to the growth response to low temperature, the temperature of the plant growth chamber was set to 15℃/5℃ (16h/8h, day/night) and 5℃ (24h) for 8 weeks using nine native moss species. Thereafter, the temperature of the plant growth chamber was set to 20℃, and then the changes of moss block area and moss color were measured. The changes of moss block area and moss color were measured using a Photoshop program, after each moss block was photographed. As a result, Atrichum undulatum (Hedw.). Beauv., Etodon luridus (Griff.) A. Jaeger, Bachythecium plumosum (Hedw.) Schimp, Plagiomnium cuspidatum (Hedw.) T.J. Kop, and Hypnum plumaeforme Wilson showed a small decrease in moss block area at low temperature, and their recovery were the fastest at 20℃. These three species had higher green values at low temperature compared to other species, and the greenness increased rapidly at 20℃. On the other hand, Atrichum undulatum (Hedw.). Beauv., Marchantia polymorpha L., and Thuidium cymbifolium (Mitt.) A. Jaeger showed the smallest block area at low temperature and the lowest recovery even at 20℃. Their green values also decreased significantly at low temperature, and maintained low green value even at 20℃. These results showed that these three moss species are sensitive to low temperature. The remaining Myuroclada maximowiczii, Plagiomnium cuspidatum, and H. erectiusculum showed moderate responses to low temperature compared to other six species of mosses.

• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.663-672
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• 2010

The pollen morphology of eleven species and three forms of the genus Rhododendron (Ericaceae) in Korea was examined using light, scanning electron and transmission electron microscopy. The pollen grains are grouped in permanent tetrahedral tetrads; viscin threads are present on the tetrads. The hexacolporate tetrads are of tricolporate monads whereby the apertures form in pairs at six points in the tetrad. The exine sculpture pattern is rugulate, scabrate or verrucate on mesocolpium but psilate, rugulate or microscabrate around the aperture on apocolpium. The exine of Korean Rhododendron pollen consists of tectum, columella, foot layer and endexine. The surface of viscin threads is more or less smooth. The threads are sometimes tangled together and occasionally divided into strands. Six types are recognized based on the pollen morphology. The types are: (1) Micranthum-type (rugulate mesocolpium and psilate apcolpium), (2) Tomentosum-type (rugulate mesocolpium and apocolpium), (3) Aureum-type (scabrate mesocolpium and rugulate apocolpium), (4) Brachycarpum-type (scabrate mesocolpium and rod shaped-microscabrate apocolpium), (5) Schlippenbachiitype (scabrate mesocolpium and round-microscabrate apocolpium) and (6) Weyrichii-type (verrucate mesocolpium).