• Korean Journal of Ichthyology
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• v.5 no.1
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• pp.96-112
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• 1993

The morphological characteristics of chum salmon Oncorhynchus keta, masou salmon. Oncorhynchus masou and rainbow trout, Oncorhynchus mykiss in Korea were studied from 1989 to 1990. It was found that 13 factors of the female and 11 factors of the male in body form, number of pyloric ceaca and gill rakers has significant specific differences. There were some differences among species in the ratios of body depth, caudal peduncle depth, dorsal fin length and anal fin length to standard length (PBL), and snout length, eye diameter, upper jaw length, and cheek to head length. In the ratio of head length to fork length of the male, chum salmon showed the highest(24.7%) value and rainbow trout the lowest(21.6%). No difference was found in the female. It was proved that number of vertebrae, gill rakers, pyloric ceaca and lateral line scales were useful taxonomical characteristics of the salmon species. In particular, the ratio of eye diameter (ED) to head length (HL) appeared to be a new taxonomic criterion for the salmons in Korean waters.

• Journal of Engineering Education Research
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• v.9 no.3
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• pp.49-61
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• 2006

The objective of this study was to propose a new framework for the creative engineering in the product family design coursework. The idea of product family design is a good solution to fulfill customer's requirements and to respond quickly for the technology change. Mass customization based on product family and product platform is a new paradigm with variety and customization through flexibility and quick responsiveness. In this study, the subjects of product family, product platform, product family map, platform leveraging strategy, morphological matrix and module based product family design were reviewed and presented. A new idea generation scheme utilizing SCAMPER method was combined with the morphological matrix approach. For the effective product family and platform design, creative efforts and approaches were utilized and implemented in the coursework process. This will help students to develop creative thinking and approaches in the engineering problem solving.

• The Korean Journal of Mycology
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• v.44 no.2
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• pp.94-99
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• 2016

Since development of the first Korean button mushroom cultivar 'Sae-Ah' in 2010, mushroom farmers have demanded an improved cultivar. Although a new cultivar, 'Saejeong', was developed in 2011, this cultivar has thus far been difficult to cultivate in typical mushroom farms. To solve this problem, another new cultivar, 'Saedo', was developed in 2012. This new cultivar was selected by genetic analysis from crossing the heterokaryon line A175 and the homokaryon line ASI1346-15. The heterokaryon A175 was a crossed line between strains ASI1038-211 and ASI1346-20. The mycelium of 'Saedo' showed good growth on compost dextrose agar at $25^{\circ}C$. The morphological traits such as the pileus (cap) and stipe of the 'Saedo' cultivar were thicker than those of the reference control 'Saejeong', and the production yield was increased by 1.89-fold compared to that of the reference control. A field experiment of the 'Saedo' cultivar has been ongoing since 2013. The yield of the 'Saedo' cultivar was found to be substantially higher than that of the reference control during the $2^{nd}$ flush.

• Toxicological Research
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• v.22 no.2
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• pp.127-133
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• 2006

Recently, we have reported that the environmental pollutant 2-bromopropane (2-BP) induces a significant embryo-fetal developmental toxicity in rats. However, the cause of developmental toxicity and the relationship between maternal and developmental toxicities could not be elucidated because the developmental toxicity of 2-BP was observed only in the presence of maternal toxicity The in vitro teratogenicity study using whole embryo culture was carried out to understand the teratogenic properties and the possible mechanism of teratogenicity induced by 2-BP in rats. Rat embryos aged 9.5 days were cultured in vitro for 48 hrs at medium concentrations of 0, 1, 3, or 10 mg/ml of 2-BP. Embryos were evaluated for growth, differentiation, and morphological alterations at the end of the culture period. At 10 mg/ml, 2-BP caused a delay in the growth and differentiation of embryos and an increase in the incidence of morphological alterations, including altered yolk sac circulation, abnormal axial rotation, craniofacial hypoplasia, open neuropore, absent optic vesicle and kinked somites. At 3 mg/ml, only a delay in the growth and differentiation of embryos was observed. There were no adverse effects on embryonic growth and development at the concentration of 1 mg/ml. The results showed that the exposure of 2-BP to rat embryos results in a developmental delay and morphological alterations at dose levels of 3 mg/ml culture media or higher and that 2-BP can induce a direct developmental toxicity in rat embryos.

• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.39-44
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• 2008

Korean cultivated bramble, which is known as Bokbunja-ddal-gi is regarded to be originated from Korea native Rubus coreanus. However, little scientific evidence and significant morphological differences between Korean cultivated bramble(KCB) and R. coreanus throw doubt on the ancestry of KCB. This study was carried out to obtain phylogenetic information on KCB by comparing its nuclear genomic background with those of R. coreanus, black(R. occidentalis) and red(R. idaeus) raspberry, blackberry(R. lanciniatus) and R. crataegifolius. A total of 99 random amplified polymorphic DNA(RAPD) markers were generated and used for phylogenetic analysis of 76 Rubus accessions. Accessions of each species were grouped into each distinct subclade by the RAPD markers at a similarity coefficient of about 0.59. The KCB subclade formed a clade with R. occidentalis and R. crataegifolius subclades at a similarity coefficient of 0.47. The R. coreanus subclade formed a clade with R. idaeus, R. lanciniatus and R. crataegifolius subclades at a similar similarity coefficient. Only one KCB accession from Hoengsung was included in R. coreanus subclade. The accession shows leaf and flower characteristics different from the rest of the KCB accessions. The phylogenetic relationship inferred from the RAPD markers suggests that the nuclear genomic background of KCB accessions which show morphological similarity to black raspberry is more closely related to black raspberry than to R. coreanus. This brings about the need for close scientific evaluations on the ancestry of KCB at both morphological and molecular levels.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.2
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• pp.77-84
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• 1988

This experiment was conducted to investigate the morphological and structual characters and the dry weight of plant (DW/pl.) concerned vegetational structure of orchardgrass pastures by the times of year, from 1 year to 7 year previous, 1986 through 1980, alternately. this experiment was carried out on the experimental fields of Yonsei University. The results are summarized as follows: 1. Population density (PD) was extremely decreased by the times of year. 2. Pasture productivity was highest at 3 year old pasture, was lowest at 5 year old pasture and was recovered at 7 year old pasture. 3. Recovery of pasture productivity was followed the increase of dry weight of plant (DW/pl.) and number of tillers per plant (NT/pl.) 4. The population density of 7 year old pasture was 14 plants per square meter. 5. The number of tillers per plant (NT/pl.), dry weight of plant (DW/pl.) plant length (PL), and plant size (PS) was frequently showed the highest values by the times of established year. 6. The stubble diameter (DIA), stubble area (SB), plant size (PS), distance between neibour plant (DIS) and leaf area index (LAI) was increased according to the times of year. 7. The dry weight of plant (DW/pl.) was positively significant correlations with the number of tillers per plant (NT/pl.) all of the established pastures, but the dry weight of a tiller (WT) was tended to increase of correlations with the dry weight of plant (DW/pl.) by the times of year. 8. Differences between morphological and structual characters was recognized according to the times of year.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.474-482
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• 2015

This study aims to investigate the patterns and incidence rates of morphological deformities during artificial fingerling production of blackhead seabream (BSB, Acanthopagrus schlegeli) juveniles by visual and soft X-ray observations of BSB juveniles (n=881) collected from four industrial hatcheries. Using both methods, we observed seven types of external deformity ($11.2{\pm}4.4%$) and eight types of skeletal deformity ($53.4{\pm}5.1%$). Lordosis occurred in all hatcheries with the highest frequency and the mean frequency was $13.1{\pm}4.4%$ (24.5% in total abnormal) by soft X-ray. Although they had a similar standard length (SL), juveniles with lordosis had a significantly lower condition factor and body weight than normally developed juveniles (P<0.05); normal distribution curves of histogram of body proportions, i.e., body height (BH)/head length (HL) and trunk (=SL-HL)/BH, indicated differences between normally developed juveniles and those with lordosis. In addition, 59% of juveniles with lordosis had vertebral curvature of less than $20^{\circ}$, generally at the $17^{th}$ vertebrae. It is expected that the above results will be used as basic data necessary for determining the cause of lordosis and for developing techniques to prevent this symptom in the fingering production industry of BSB juveniles.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.11-16
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• 2011

This study was conducted to identify the morphological characteristics and variations level by site environment of native bermudagrass (Cynodon spp.) from costal and island region in South Korea. Soil chemical properties and morphological characteristics were investigated. There were significant differences in plant height, leaf width, leaf length, cotton on leaf blade, stolon, and number of seed per spike depending on where they were collected from natural habitat. We have discovered a variety of variation among the investigated traits in Korean native bermudagrass ecotypes. There were broad leaf and fine leaf types of native bermudgarass in S. Korea. Adaptability was in very high on inadequate environment in bermudagrass with broad leaf types, it has also been suggested that management worth in terms of use. These results may provide basic information for bermudagrass breeding development and the collected types during this investigation would be worth being preserved as genetic resources for further breeding purposes.

• Korean Journal of Plant Resources
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• v.33 no.1
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• pp.40-49
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• 2020

The objectives of this study were to evaluate total phenolic content (TPC) and individual phenolic compounds in leaves of perilla genetic resources, assess whether they could be used as distinguishing factor among germplasms, and evaluate their relationship with some quantitative and qualitative morphological characters. TPC and individual phenolic compounds were determined using Folin-Ciocalteu method and UPLC-PDA system, respectively. Wide variations in TPC (7.99 to 133.70 mgGAE/g DE), rosmarinic acid (ND to 21.05 mg/g DE), caffeic acid (ND to 1.17 mg/g DE), apigenin-7-O-diglucuronide (ND to 2.21 mg luteolin equivalent (mgLUE)/g DE), scutellarein-7-O-glucuronide (ND to 5.25 mg LUE/g DE), and apigenin-7-O-glucuronide (ND to 2.81 mg LUE/g DE) were observed. Intensities of green pigment at abaxial and adaxial leaf surfaces were positively correlated with phenolic compounds whereas leaf length and width had negative correlation. Purple pigmented accessions were shorter in leaf length and width but exhibited higher amount of phenolic compounds compared to green pigmented accessions in most cases. Leaf shape was not related with content of phenolic compounds, color of leaves, and length/width of leaves. TPC and individual phenolic compounds along with morphological characters could be useful distinguishing factors for perilla genetic resources.

• Korean Journal of Ichthyology
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• v.23 no.3
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• pp.217-224
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• 2011

The seven leptocephali (14.6~68.0 mm in total length) of the family Ophichthidae, from the East Sea of Korea, were identified using 12S rRNA 861-bp sequences and their morphological development were described. Our seven leptocephali were identified to Echelus uropterus based on genetic distance (d=0.000) being well consistent with that of adult E. uropterus. Our seven leptocephali of E. uropterus are characterized by morphological combinations: caudal fin present; the melanophores present in series of nine gut swellings; total myomeres 154~158; body depth in total length less than 10%; eight black horizontal bands present from anus to caudal fin base. Our morphological and molecular results suggest that E. uropterus may be an intermediate group between subfamily Ophichthinae and Myrophinae.