• Journal of Life Science
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• v.16 no.5
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• pp.812-827
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• 2006

To investigate the population structure and geographic distance among anchovies (Engraulis japonicus) in Korea, we compared and analyzed the mitochondrial DNA control region sequences (227 bp) of anchovies from 12 localities in inshore and offshore waters. The sequence analysis of 84 individuals showed 29 haplotypes, ranging in sequence divergence by pairwise comparisons from 0.3% to 3.5% (1 bp-12 bp). E9 haplotype of anchovies were found largely in inshore waters and also in offshore waters, which was regarded as the major source in Korean waters (58.3%). However, E26, E27, E28, and E29 haplotypes were found in westsouthern (locality 10, four among 7). Phylogenetic analysis using PHYLIP was divided into two clades (clade A and B). Most of the haplotypes, excluding E26, E27, E28, and E29, were strongly supported by bootstrap analysis (>75%), whereas the relationship between clade A and B was weakly supported by bootstrap analysis (51%). High levels of genetic diversity were found; haplotype diversity (H)=0.75-1.00, and nucleotide diversity $({\pi})=0.015-0.0244$. Analysis of $F_{ST}$ between populations in inshore waters ranged in 0.01-0.05, whereas those of offshore waters ranged in 0.01-0.58. A high gene flow occurred in inshore (Nm=22.61-34.22) and offshore (Nm=11.57-45.67) populations. The distribution of mitochondrial DNA haplotypes between westsouthern and other populations was suggestive of significantly different differentiation ($F_{ST}$=0.20-0.59, p<0.05; d=0.52, p=0.00; ${\phi}=0.02-0.41$, p＜0.05). These results suggested that the overall anchovy population in the Korean peninsula caused considerable migration due to the mitochondrial gene flow between inshore and offshore populations to form a genetically homogenous and panmictic structure, although a heterogeneous population was found in this study.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.83-89
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• 2012

Flavobacterium johnsoniae was isolated from farmed rainbow trout Oncorhynchus mykiss in Korea, and its biochemical and molecular characterization was determined. Yellow-pigmented bacterial colonies were isolated from 18 of 64 fish samples (28.1%) on trypticase soy agar plates, and their biochemical profiles were characterized by API 20E and API 20NE test kits. F. johnsoniae was identified by biochemical phenotyping of factors including rapid gliding motility, Gram-negative condition, oxidase- and catalase-positive status, Congo red absorption, nitrate reduction, ${\beta}$-galactosidase production, acid production from glucose, and gelatin and casein hydrolysis. PCR and subsequent sequencing of 16S rRNA confirmed that the yellow-pigmented colonies were most similar to F. johnsoniae. The alignment analysis of 16S rRNA sequences also showed that all 18 rainbow trout isolates had highly similar homologies (97-99% identity). One isolate was selected and named FjRt09. This isolate showed 98% homology with previously reported F. johnsoniae isolates, and in phylogenetic analysis was more closely grouped with F. johnsoniae than with F. psychrophilum, F. columnare, or F. branchiophilum. This is the first report on the occurrence and biochemical characterization of F. johnsoniae isolated from rainbow trout in Korea.

• Korean Journal of Plant Resources
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• v.35 no.6
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• pp.805-819
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• 2022

The taxonomic status and phylogenetic relationship of Opuntia monacantha Haw. f. jejuensis J. K. Kim ex Y. S. Yang (Jejubaiknyuncho), which is native to southern coast of Jeju Island, Korea was analyzed using DNA markers obtained from Korean Opuntia. Opuntia stricta Haw., O. humifusa Raf., and O. humifusa Raf. f. jeollaensis E. J. Kim and S. S. Whang, native or cultivated in Korea, have no stripes on the back of tepals and have a purple pulp, whereas O. monacantha f. jejuensis has purple stripes on the back of tepals and a greenish-yellow pulp color. Opuntia monacantha has purple stripes on both the front and back of its tepals, whereas stripes appear only on the back of tepals of O. monacantha f. jejuensis. Opuntia monacantha f. jejuensis was assigned to Elatae series in phylogenetic analysis and was found to be more closely related to O. monacantha subsp. arechavaletae (Speg.) Guiggi, compared with O. monacantha at a molecular level. Based on its phylogenetic and morphological differences from O. monacantha and O. monacantha subsp. arechavaletae, which are native or have been cultivated in Jeju areas, O. monacantha f. jejuensis was named as a new forma in this study.

• Korean journal of food and cookery science
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• v.20 no.2
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• pp.151-157
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• 2004

This study was designed firstly to measure the job satisfaction levels of F＆B (Food ＆ Beverage) personnel in hotels by using JDI (Job Descriptive Index) and secondly to identify the effects of job satisfaction on intention to quit by job type. Of 498 respondents, there were 245 employees in the back of the house (eBOH) and 253 in the front of the house (eFOH). From an analysis on job satisfaction, total JDI, score was 136.57${\pm}$11.48 out of a maximum 210 and the payroll (14.79 out of 21, 70.4%) facet of JDI was the highest job satisfaction followed by co-workers (36.07 out of 54, 66.8%), supervision (35.37 out of 54, 65.5%), promotion (17.45 out of 27, 64.6%) and work itself (32.86 out of 54, 60.8%). In comparison between the job satisfaction of eBOH and eFOH, eFOH perceived significantly higher than eBOH for job itself (p＜.001) and total job satisfaction (p＜.01). No facets of JDI were significant by job level, but work itself (p＜.05), payroll (p＜.05), supervision (p＜.01) and promotion (p＜.05) were significant by work section in eFOH,. In addition, no facets except work itself were significant by either job level or work section in eFOH. Finally, among job satisfaction facets, payroll had a negative effect on intention to quit whereas supervision had a positive effect on it in eBOH. On the other, work itself affected intention to quit positively but promotion affected it negatively. The findings confirmed the necessity for internal marketing focusing on the lower level of job satisfaction facets and indicated that such a focus would improve organizational effectiveness.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.1
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• pp.3702-3711
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• 1975

This study was originated to investigate the imparired parts of the mist and dust blowers and intended to analyze the causes of their failures by the use of the Weibull probability paper. By the use of the paper, the parts which were needed to change the design, the force of the urgency, the mean time between failures of the parts and the basic causes of the troubles could be predicted. The survey showed that the following parts got out of order: (A) flexible rubber hose, (B) blowing fan, (C) lead valve, (D) piston ring. (E) crank main bearing, (F) coil in magneto and (G) needle valve in carburettor. The analysis of the survey indicated that the parts G, C, E and D were belonged to "wear-out failure", and that the mean time between failures became shorter in order as indicated above. To insure longer lives of those parts, it would be necessary to change the design and the material and to upgrade operators mechanical technique of the mist and dust blower. The failure of the parts A, B and F was classified as "randomfailure", and they did not seem to be the "wear-out" at that time. The parts B and F was evaluated as "initial failure". Quality controls and operating tests by the producer. and the operational training for users should be strengthened so as to eliminate these failures. Were the failures only in the parts A, C, D, E, F and G, it could be said that the "reliability" of the mist and dust blower would fall to 10 percent in the second year, and 50 percent of the mist and dust blowers would fail in all parts A, C, D, E, F and G before the blower would have control insect and disease in 58.2 hectares. The use of the Weibull probability paper for analyzing failures of the mist and dust blowers was effective in that it analyzed failure in the relationship between strength of the parts and users actual circumstanoes.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.485-493
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• 2019

Objective: This study was undertaken to investigate the genetic characteristics of Berkshire (BS), Landrace (LR), and Yorkshire (YS) pig breeds raised in the Great Grandparents pig farms using the single nucleotide polymorphisms (SNP) information. Methods: A total of 25,921 common SNP genotype markers in three pig breeds were used to estimate the expected heterozygosity ($H_E$), polymorphism information content, F-statistics ($F_{ST}$), linkage disequilibrium (LD) and effective population size ($N_e$). Results: The chromosome-wise distribution of $F_{ST}$ in BS, LR, and YS populations were within the range of 0-0.36, and the average $F_{ST}$ value was estimated to be $0.07{\pm}0.06$. This result indicated some level of genetic segregation. An average LD ($r^2$) for the BS, LR, and YS breeds was estimated to be approximately 0.41. This study also found an average $N_e$ of 19.9 (BS), 31.4 (LR), and 34.1 (YS) over the last 5th generations. The effective population size for the BS, LR, and YS breeds decreased at a consistent rate from 50th to 10th generations ago. With a relatively faster $N_e$ decline rate in the past 10th generations, there exists possible evidence for intensive selection practices in pigs in the recent past. Conclusion: To develop customized chips for the genomic selection of various breeds, it is important to select and utilize SNP based on the genetic characteristics of each breed. Since the improvement efficiency of breed pigs increases sharply by the population size, it is important to increase test units for the improvement and it is desirable to establish the pig improvement network system to expand the unit of breed pig improvement through the genetic connection among breed pig farms.

• Corrosion Science and Technology
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• v.2 no.5
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• pp.212-218
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• 2003

Electronic properties of passive films formed on Ti at film formation potentials $(E_f)V_{SCE}$ in pH 8.5 buffer solution and in an artificial seawater were examined through the photocurrent measurement and Mott-Schottky analysis. The passive films formed on Ti in pH 8.5 buffer solution exhibited a n-type semiconductor with a band gap energys $(E_g);E_g^{n=2}=3.4$ eV for nondirect electron transition, and $E_g^{n=0.5}=3.7$ eV for direct electron transition. These band gap values were almost same as those for the passive films formed in artificial seawater, indicating that chloride ion ($Cl^-$ in solution did not affect the electronic structure of the passive film on Ti. $E_g$ for passive films formed on Ti were found to be greater than those ($E_g^{n=0.5}=3.1$ eV, $E_g^{n=2}=3.4$) for a thermal oxide film formed on Ti in air at $400^{\circ}C$. The disorder energy of passive film, determined from the absorption tail of photocurrent spectrum, was much greater than that for the thermal oxide film farmed on Ti in air at $400^{\circ}C$. The greater $E_g$ and the higher disorder energy for the passive film compared with those for the thermal oxide fIlm suggest that the passive film on Ti exhibited more disorded structure than the thermal oxide film. The donor density (about $2.4{\times}10^{20}cm^{-3}$) for the passive film formed in artificial seawater was greater than that (about $20{\times}10^{20}cm^{-3}$) formed in pH 8.5 buffer solution, indicating that $Cl^-$ increased the donor density for the passive film on Ti.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.487-493
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• 2016

The moment analysis of lysozyme was implemented using chromatograms that were obtained from weak cation exchange column in high performance liquid chromatography system. Three elution sodium phosphate buffers containing 1.0, 0.75, 0.5M sodium chloride were used. Experiments were conducted by varying flow rate, elution sodium chloride concentration, and lysozyme solute concentration. The general rate (GR) model was employed to calculate the first moment and the second moment. By plotting $L/u_0$ vs. $({\mu}_1-t_0)/(1-{\varepsilon}_e)(1-{\varepsilon}_i)$] equilibrium constants (K) were obtained from first moment analysis. Intra-particle diffusivity was obtained from theoretical plate number data. Based on the results of moment analysis, van Deemter plots were drawn in order to investigate the contributions of $H_{ax}$, $H_f$, and $H_d$ to total Height Equivalent to a Theoretical Plate (HETP, $H_{total}$). The effect of intra-particle diffusion ($H_d$) was the most dominant factor contributing to HETP while external mass transfer ($H_f$) was negligible factor.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.637-642
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• 2020

Fusarium wilt in tobacco caused by the fungus Fusarium oxysporum f. sp. nicotianae is a disease-management challenge worldwide, as there are few effective and environmentally benign chemical agents for its control. This challenge results in substantial losses in both the quality and yield of tobacco products. Based on an in vitro analysis of the effects of different phenylpropanoid intermediates, we found that the early intermediates trans-cinnamic acid and para-coumaric acid effectively inhibit the mycelial growth of F. oxysporum f. sp. nicotianae strain FW316F, whereas the downstream intermediates quercetin and caffeic acid exhibit no fungicidal properties. Therefore, our in vitro screen suggests that trans-cinnamic acid and para-coumaric acid are promising chemical agents and natural lead compounds for the suppression of F. oxysporum f. sp. nicotianae growth.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.138-143
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• 2005

Finite Element analysis is widely applied to elevated temperature forging processes and shows a lot of information of plastic deformation such as strain, stress, defects, damages and temperature distributions. In highly elevated temperature deformation processes, temperature of material and tool have significant influence on tool life, deformation conditions and productivities. To predict temperature related properties accurately, adequate coefficients of not only contact heat transfer between material and dies but also convection heat transfer due to coolants are required. In most F.E analysis, too higher value of contact heat transfer coefficient is usually applied to get acceptable temperature distribution of tool. For contact heat transfer coefficients between die and workpiece, accurate values were evaluated with different pressure and lubricants conditions. But convection heat transfer coefficients have not been investigated for forging lubricants. In this research, convection heat transfer coefficients for cooling by emulsion lubricants are suggested by experiment and Inverse method. To verify acquired convection and contact heat transfer coefficients, tool temperature was measured for the comparison between measured tool temperature and analysis results. To increase analysis accuracy, repeated analysis scheme was applied till temperature of the tool got to be in the steady-state conditions. Verification of heat transfer coefficients both contact and convection heat transfer coefficients was proven with good accordance between measurement and analysis.