• Entomological Research
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• v.48 no.6
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• pp.480-489
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• 2018

Due to the increasing interest in natural biopolymers including chitin, the exploitation of economic and easily accessible chitin sources with good physicochemical properties is nowadays required. In view of this fact, in the current study chitin was extracted and physicochemically characterized from six Cicadas (Hemiptera: Homoptera: Cicadoidea) species collected from Mediterranean region of Turkey (2014-15). Chitin was extracted using a classic extraction method that includes acid and base treatment. TGA results revealed a remarkable increase ($410-412^{\circ}C$) for all the six Cicada species compared to other chitin samples extracted from various sources. For all of the six selected species the chitin contents on the dry basis were determined as 6.7% for Cicadatra atra, 5.51% for C. hyalina, 8.84% for C. platyptera, 4.97% for Cicada lodosi, 6.49% for C. mordoganensis, and 5.88% for Cicadetta tibialis. The surface morphology of chitin isolates from Cicada species was observed to consist of nanofibers and nanopores.

• Journal of Plant Biology
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• v.30 no.3
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• pp.215-223
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• 1987

Pollen grains of six geners and six species from Korean Theaceae were observed with light and scanning electron microscopes. Pollen morphology divided the investigated species into the tricolporoidate Theoideae and the tricolporate Ternstroemiodideae. On the basis of surface sculpturing pattern, further palynological relationships and classificatin were understood. Some of the nomenclatural problems were discussed along with the palynological results.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.4 no.1
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• pp.16-27
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• 2023

Primary succession on bare rocks is a challenge for invaders, including one of which was plants. The invasion of bare rock by exotic species raises the question of whether their presence hinders or facilitates succession. This study aimed to determine the role of exotic species in primary succession in six overburden (OB) coal mines using a chronosequence approach. Vegetation analysis was undertaken using line transects. Measurements were carried out on the absolute and relative coverage of each species. Native and exotic species were identified and grouped using information from local communities, identification books, and websites. The relationship between time and number of species, time, and relative dominance of exotic and native species was analyzed using Pearson's correlation. Species number and dominance data were analyzed descriptively. The number of native species from the six OB heaps was higher (57) than that from exotic heaps (50). Neither the number of species nor the coverage showed a significant relationship with time. Exotic species predominated throughout the age of the embankment but tended to decrease over time. Temporary dominance by exotic species plays a role in assisting primary succession in the OB. This process might be prolonged without the temporary dominance of exotic species during early primary succession.

• Animal cells and systems
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• v.3 no.2
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• pp.193-197
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• 1999

A peroxidase-antiperoxidase method was used to detect the cells showing immunoreactivities to six hormone antibodies in the alimentary tracts of six frog species, Rana nigromaculata, R. rugosa, R. amurensis coreana, R. catesbeiana, Bombina orientalis, and Hyla arborea japonica, inhabiting Korea. The cells immunoreactive to gastrin and cholecystokinin-8 were observed in the pylorus of the stomachs and in the small intestines of all frog species examined. In contrast, these somatostatin-immunoreactive cells were identified in the esophagus and the whole gastrointestinal tracts, but were absent from the large intestines in R. rugosa, R. catesbeiana, B. orientalis and H. arborea japonica. The pancreatic polypeptide (PP)-immunoreactive cells represented their distribution limited to the small intestines of R. amurensis coreana and H. arborea japonica, and they were additionally identified in the pylorus of the stomachs in the other four species. Serotonin- and glucagon- Immunoreactive cells revealed different regional distributions in which the former were observed throughout the whole alimentary tracts in all frog species investigated, whereas the latter were not found in these regions at all. Endocrine cells were relatively abundant in the pyloric portion of the stomach compared to other organs. The present study showed that all endocrine cells except for PP had a similar distribution in the alimentary tracts of all frog species used.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.2
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• pp.218-230
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• 2020

The single anatomical attribute that has the greatest influence on acoustic scattering from fish is the presence or absence of a swimbladder. This study examined the effect of removing the gas from the swimbladder on the broadband backscattering characteristics of six species of swimbladdered fish: striped beakperch Oplegnathus fasciatus, black scraper Thamnaconus modestus, dark-banded rockfish Sebastes inermis, goldeye rockfish Sebastes thompsoni, black rockfish Sebastes schlegeli and panther puffer Takifugu pardalis. Before and after removing the gas from the swimbladder, the species-specific, frequency-dependent backscattered echo signals from anaesthetized individuals of each fish species were measured at approximately 1° intervals spanning a 90° aspect angle range from -45° (head down) to +45° (head up) using a broadband echo sounder operating at 100-200 kHz. The relationship between the wavelength-normalized backscattering cross section (σ/λ²) and fish length (L/λ) was calculated for each species. The average σ/λ² value for the six fish species at a L/λ range of 19.79-25.85, with a mean of 22.89, was reduced by approximately 52.3% when the gas was removed.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.272-283
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• 2023

The spider fauna of rice fields, marshes, and reclaimed lands was intensively explored in 2015-2022. During the seasonal survey, six Tibellus spiders were collected; two of them, Tibellus fengi Efimik, 1999 and Tibellus japonicus Efimik, 1999, were new to Korean spider fauna and four of them were identified as new species, Tibellus deokjeok sp. nov., Tibellus gimcheon sp. nov., Tibellus sihwa sp. nov., and Tibellus yeongdong sp. nov.. Four new species are similar to each other and known species in the shape of the genital organ and body appearance in both sexes, but can be distinguished from the other Tibellus members by the shape of embolus, conductor, retrolateral tibial apophysis, and ventral tibial apophysis in male and median septum, receptaculum, spermatheca, and copulatory duct in female. The present study taxonomically describes these six Tibellus spiders with diagnoses, measurements, and morphological photos with a key to the Korean Tibellus species.

• Animal Systematics, Evolution and Diversity
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• v.27 no.3
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• pp.246-261
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• 2011

Adult chironomid collections were carried out near Namdae stream located at Jeollabuk-do, Muju-gun, Mujueup, Dangsan-ri in 2008 and 2009. Among 21 species of the tribe Tanytarsini identified from Muju collections, six new species (Cladotanytarsus neovanderwulpi, Paratanytarsus paramikesecumdus, Rheotanytarsus parapentapodus, Rheotanytarsus sungili, Tanytarsus neotamaoctavus, and Tanytarsus synyunosecundus) and four previously unrecorded species (Cladotanytarsus vanderwulpi, Paratanytarsus inopertus, Tanytarsus tamagotoi, and Tanytarsus uresiacutus) were confirmed. They are fully described with illustrations. As a result of this report, the Korean fauna of Tanytarsini consists of 37 species, 6 genera. In total, 128 species, 52 genera, 5 subfamilies of the family Chironomidae are listed in Korea.

• Journal of the Korean Wood Science and Technology
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• v.47 no.1
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• pp.80-89
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• 2019

Pine barks are important biomass resources because they are utilised in the production of pine wood and rosins. However, no chemical study has been conducted on the hydrophilic status of pine barks in Indonesia. This aim of this study is to explore the hydrophilic extracts of the barks from six Pinus species (P. elliotii, P. caribeae, P. oocarpa, P. merkusii P. montezumae, and P. insularis). The hydrophilics of pine barks were analysed using gas chromatography-mass spectrometry. The presence of polyphenol contents in the ethanol extracts obtained from the barks of six Pinus species was determined using the tannin-formaldehyde method, Folin-Cioucalteu assay, and vanillin-HCl assay. The ethanol and hot water soluble extractives derived from inner barks were higher in quantity when compared to those derived from the outer bark samples. The polyphenol measurement showed that the highest value of total phenol content was derived from the outer bark of P. montezumae whereas those of the total phenol and tannin- formaldehyde contents were derived from the inner and outer barks of P. oocarpa. GC-MS analysis revealed that nitrogenous compounds are dominant constituents in the inner and outer barks of the six species, followed by sugars and monophenolics, respectively.

• Animal Systematics, Evolution and Diversity
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• v.25 no.1
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• pp.107-119
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• 2009

Six Ichneumonini species, Barichneumon constrictus (Uchida, 1956), Ctenichneumon albomaculatus (Uchida, 1956), Diphyus salicatorius (Gravenhorst, 1820), Ichneumon ohtaniensis Uchida, 1926, Ichneumon kuroishiensis (Uchida, 1929) and Stenichneumon odaiensis Uchida, 1932, are reported for the first time in Korea. Photographs and redescriptions are provided.

• Animal cells and systems
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• v.8 no.3
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• pp.155-163
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• 2004

Tenuidraconema koreensis, a new species of free-living marine nematodes, collected from the subtidal coarse sediments and various invertebrates of Namae, is described. The new species differs from T. fiersi Decraemer, 1989, the only other species in the genus, by having the combination of the following characters: the position of twelve cephalic adhesion tubes in both sexes (anterior six cephalic adhesion tubes inserted on the rostrum and posterior six inserted on the body annules), and the number of posterior sublateral adhesion tubes (12 in male and 13 in female) and posterior subventral adhesion tubes (15 in male and 19 in female). This paper contains the description of the new species with illustrations and scanning electron microscope (SEM) photomicrographs. This is the first discovery of the monotypic genus Tenuidraconema outside the type locality.