• The Plant Pathology Journal
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• v.36 no.4
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• pp.314-322
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• 2020

Interplay between histone acetylation and deacetylation is one of the key components in epigenetic regulation of transcription. Here we report the requirement of MoHDA1-mediated histone deacetylation during asexual development and pathogenesis for the rice blast fungus, Magnaporthe oryzae. Structural similarity and phylogenetic analysis suggested that MoHDA1 is an ortholog of Saccharomyces cerevisiae Hda1, which is a representative member of class II histone deacetylases. Targeted deletion of MoHDA1 caused a little decrease in radial growth and large reduction in asexual sporulation. Comparison of acetylation levels for H3K9 and H3K14 showed that lack of MoHDA1 gene led to significant increase in H3K9 and H3K14 acetylation level, compared to the wild-type and complementation strain, confirming that it is a bona fide histone deacetylase. Expression analysis on some of the key genes involved in asexual reproduction under sporulation-promoting condition showed almost no differences among strains, except for MoCON6 gene, which was up-regulated more than 6-fold in the mutant than wild-type. Although the deletion mutant displayed little defects in germination and subsequent appressorium formation, the mutant was compromised in its ability to cause disease. Wound-inoculation showed that the mutant is impaired in invasive growth as well. We found that the mutant was defective in appressorium-mediated penetration of host, but did not lose the ability to grow on the media containing H₂O₂. Taken together, our data suggest that MoHDA1-dependent histone deacetylation is important for efficient asexual development and infection of host plants in M. oryzae.

• Reproductive and Developmental Biology
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• v.31 no.3
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• pp.207-213
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• 2007

This study was carried out to examine gene expression altered in endometrium of Korean cattle (Hanwoo) with endometritis using microarray. In this study, 4,560 diferentially expressed genes (DEGs) were identified in the endometrium of Hanwoo. Of 4,560 DEGs, 2,026 genes were up-regulated, while 2,536 genes were down-regulated in endometritis. Of them, top 10 regulated genes were listed. Filamin A, pancreatic anionic trypsinogen, Rho GDP dissociation inhibitor alpha, collagen type VI alpha 1, butyrate response factor 2, aggrecanses-2, annexin 14, aminopeptidease A, orphan transporter v7-3, and epithelial stromal interaction 1 were up-regulated, while MHC class II antigen, integrin-binding sialoprotein, uterine milk protein precursor, down-regulated in colon cancer 1, glycoprotein 330, dickkopf-1, cfh protein, $Ca^{2+}-dependent$ secretion activator, UL16 binding protein 3, and proenkephalin were down-regulated in the endometritis. Our results suggest that these genes could be useful biomarkers for diagnosis Hanwoo's endometritis.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.201-210
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• 1998

Sex ratios, and patterns of tree size and growth variation, resource allocation, spatial and age class distribution between the sexes were investigated in natural populations of the sexual trees, R. trichocarpa and R. sylvestris, and the mainly asexual, clonal tree, R. javanica of the dioecious Rhus (Anacardiaceae) distributed in Korea. Sex ratios for three species exhibited a significant degree of female bias, but among the populations, sex ratios were seen to vary quite widely. The measurement of tree size and annual increment of male trees in R. trichocarpa and R. sylvestris were significantly higher than those of female trees, but not significantly different in R. javanica. In all of the species, flowering branch number per individual and inflorescence number per branch of males outnumbered those of females. Branch number per individual, rachis(leaf) number per branch and rachis(leaf) number per inflorescence were more in females than in males. These results were considered as reproductive efforts to increase the pollen supply in males and the fruit production in females. Spatial distribution analysis in two different populations of R. trichocarpa indicated that males and females were randomly distributed in space, but seedlings were clumped around parental trees. Analysis of age class distributions between the sexual reproduction trees, R. triclaocarpa and R. sylvestris, and the asexual, clonal tree, R. javanica showed a different distribution in frequencies of males and females in each age class. These results showed that sexual and asexual reproduction tree species had almost different preference of habitats, and different sex ratio and annual growth.

• English Language & Literature Teaching
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• v.15 no.4
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• pp.109-136
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• 2009

This study investigates English medium instruction (EMI) in an institution of higher education in Seoul, Korea to see whether this course creates cultural correction (reproduction of inequitable relations of power in EMI settings) or cultural continuity (opportunities for transporting students into a third space and enabling them to explore cultural diversity and to create new knowledge for themselves). A single site where EMI is carried out, a class on fairy tales and child education taught by a native English speaking professor, was chosen because it was hypothesized that the professor would display some of her unconscious dominant cultural orientation. The results of the study show that there more cases of cultural correction than there were of cultural continuity. Cases of cultural correction included lack of knowledge about the local context, fixing Korean classroom discourse as if it were American classroom discourse, and reproducing orientalism in the local educational setting. Cases of cultural continuity included using comparison to consider the cultural reality of the milieu, creating new knowledge for the local milieu, and learning as a dynamic ongoing process. Implications of this research are discussed including the important realization that EMI should be managed by subject specialists who are trained in language education and have knowledge of the students' needs and discourse in the L1 and in the local context.

• Women's Health Nursing
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• v.19 no.4
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• pp.219-229
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• 2013

Purpose: This study was conducted to identify awareness levels in regard to preconception care and gender differences targeting single undergraduate students in their 20s. Methods: The study participants were 867 single undergraduate students aged 20~29 (523 women, 344 men). This was a descriptive research, in which awareness levels of preconception care and pregnancy were identified the through questionnaire surveys. Results: Gender differences in the awareness of reproductive care before conception were found. Generally, women's awareness of issues related to preconception care and pregnancy was higher than that of men. Women recognized risk factors in pregnancy ($x^2$=22.85, p<.001) and positive behaviors ($x^2$=10.91, p=.012) better than men. Women's awareness of preconception care was significantly higher than that of men (t=8.37, p<.001). The awareness levels of the students who completed a reproduction related class (t=3.16, p=.002) and the students who knew about folic acid (t=-10.78, p<.001) in preconception care were statistically significantly higher. Conclusion: The results indicate that the ways to educate and alert students to major risk factors before pregnancy and other reproductive care content before conception is to provide education both single women and single men.

• Journal of Ecology and Environment
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• v.46 no.1
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• pp.18-30
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• 2022

Background: Bees and flowering plants associations were initially began during the early Cretaceous, 120 million years ago. This coexistence has led to a mutual relationship where the plant serves as food and in return, the bee help them their reproduction. Animals pollinate about 75% of food crops worldwide, with bees as the world's primary pollinator. In general, bees rely on flower scents to locate blooming flowers as visual clue is limited and also their host plants from a distance. In this review, an attempt is made to collect some relevant 107 published papers from three scientific databases, Google Scholar, Scopus, and Web of Science database, covering the period from 1959 to 2021. Results: Flowering plants are well documented to actively emit volatile organic compounds (VOCs). However, only a few of them are important for eliciting behavioral responses in bees. In this review, fifty-three volatile organic compounds belonging to different class of compounds, mainly terpenoids, benzenoids, and volatile fatty acid derivatives, is compiled here from floral scents that are responsible for eliciting behavioral responses in bees. Bees generally use honest floral signals to locate their host plants with nectar and pollen-rich flowers. Thus, honest signaling mechanism plays a key role in maintaining mutualistic plant-pollinator associations. Conclusions: Considering the fact that floral scents are the primary attractants, understanding and identification of VOCs from floral scent in plant-pollinator networks are crucial to improve crop pollination. Interestingly, current advances in both VOCs scent gene identification and their biosynthetic pathways make it possible to manipulate particular VOCs in plant, and this eventually may lead to increase in crop productivity.

• Korean Journal of Social Welfare Studies
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• v.44 no.2
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• pp.437-463
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• 2013

As polarization and class reproduction between generations are considered to be serious problems in Korean society, increasing number of assortative mating, which means marrying between homogeneous family background, income class, and educational background, is on the spotlight socially. Some worry that the increase of assortative mating can reinforce closure of social mobility so it deepens inequality and limits class mobility between generations. This research analyzes the effects of accomplishment characteristics of husbands and wives and ascriptive characteristics of parents which consist the concept of assortative mating, on income, consumption, and assets those represent economic status of a family. The purpose of this research is to suggest empirical understanding on the role of assortative mating that affect on inequality within generations and income mobility between generations in Korean society. In the result of multiple regression analysis on the effect of assortative mating on income, consumption, and assets, high educational background was the factor that increase income and consumption level as accomplishment characteristics of assortative mating. As ascriptive characteristics of assortative mating, educational homogeneous of fathers was the factor that increased asset level. While accomplishment characteristics affect income and consumption, ascriptive characteristics of homogeneous had significant effect on assets. Thus, it was found that transfer between generations had effects around asset rather than income. In particular, ascriptive characteristics in young husbands and wives aged 20s or 30s had significant effect only on the assets.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.1
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• pp.87-95
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• 1996

A new design scheme for the fuzzy pattern matching classifier (FPMC) is proposed. in conventional design of FPMC, there are no exact information about the membership function of which shape and number critically affect the performance of classifier. So far, a trial and error or heuristic method is used to find membership functions for the input patterns. But each of them have limits in its application to the various types of pattern recognition problem. In this paper, a new method to find the appropriate shape and number of membership functions for the input patterns which minimize classification error is proposed using genetic algorithms(GAs). Genetic algorithms belong to a class of stochastic algorithms based on biological models of evolution. They have been applied to many function optimization problems and shown to find optimal or near optimal solutions. In this paper, GAs are used to find the appropriate shape and number of membership functions based on fitness function which is inversely proportional to classification error. The strings in GAs determine the membership functions and recognition results using these membership functions affect reproduction of next generation in GAs. The proposed design scheme is applied to the several patterns such as tire tread patterns and handwritten alphabetic characters. Experimental results show the usefulness of the proposed scheme.

• Korean Journal of Animal Reproduction
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• v.14 no.3
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• pp.183-190
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• 1990

These studies were carried out ot investigate the effects of estrous cow serum(ECS), fetal calf serum(FCS), bovine follicular fluid(BFF) and matured cumulus cell(MCC) on in vitro maturation and fertilization of bovine follicular oocytes. The ovaries were obtained from slaughtered Korean native cows. The follicular oocytes surrounded with cumulus cells were recovered by aspirating follicular fluid from the visible follicles of diameter 3-5mm. The follicular oocytes were cultured in TCM-199 medium containing hormones, FCS, ECS, BFF and MCC for 24~48 hrs. in a incubator with 5% CO2 in air at 38.5$^{\circ}C$ and then matured oocytes were again cultured for 18$^{\circ}C$20 hrs. with motile capacitated sperm in the TCF(Tyrode calcium-free) solution containing 200$\mu\textrm{g}$/ml of heparin. The results obtained in these experiments were summarized as follows : 1. The oocytes classified as "A, B, C, D and Degenerative" depending morphological integrity and those were 61.4%, 12.1%, 19.2%, 4.2% and 3.0% of the total oocytes harvested, respectively. The maturation and fertilization rate of the A, B, C class follicular oocytes, cultured in the TCM-199 medium supplemented with 10% FCS were 89.1%, 78.0%, 52.6% and 78.1%, 33.3%, respectively. 2. The maturation and fertilization rate of the follicular oocytes cultured in TCM-199 medium supplemented with 5%~20% ECS and FCS were 74.0%~80.6, 26.2%~30.0% and 71.7%~76.9%, 51.9%~58.0%, and those values were higher the supplement of ECS than FCS. 3. The maturation rate(68.0%~64.6%) and fertilization rate(59.6%~60.4%) of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and 20~30% BFF were higher than those of follicular oocytes cultured TCM-199 medium supplemented with 10% FCS and 10% and 50% BFF. 4. The maturation rate(76.5%) and fertilization rate(61.7%) of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and 1$\times$106/ml cumulus cells were higher than those of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and 1$\times$104~5/ml and 1$\times$108/ml cumulus cells.lus cells.

• Korean Journal of Animal Reproduction
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• v.14 no.4
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• pp.237-244
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• 1990

These studies were carried out to investigate the effects of the follicles size, hormone supplementation, semen types and capacitation methods on in vitro maturation and fertilization of bovine follicular oocytes. The ovaries were obtained from slaughtered Korean Native cows. The follicular oocytes surrounded with cumulus cells were recovered by aspirating follicular fluid from the visible follicles of diameter 3~5mm. The follicular oocytes were cultured in TCM-199 medium containing hormones, FCS, ECS, BFF and MCC for 24~48hrs. in a incubator with 5% CO2 in air at 38.5$^{\circ}C$ and then matured oocytes were again cultured for 18~20hrs. with motile capacitated sperm in the TCF(Tyroide calcium-free) solution containing 200$\mu\textrm{g}$/ml of heparin. The results obtained in these experiments were summarized as follows : 1. The oocytes classified as "A, B, C, D and Degenerative" depending morphological integrity and those were 61.4%, 12.1%, 19.2%, 4.2% and 3.0% of the total oocytes recovered, respectively. The maturation and fertilization rate of the A, B, C class follicular oocytes, cultured in the TCM-199 medium supplemented with 10% FCS were 89.1%, 78.0%, 52.6% and 78.1%, 66.1%, 33.3%, respectively. 2. The average number of the follicular oocytes recovered from follicles size, 1~2mm, 3~5mm and above 5mm in dimeter were 67, 98 and 63, respectively. The maturation and fertilization rate of the follicular oocytes, cultured in the TCM-199 medium were 56.7%, 82.5%, 46.0% and 44.8%, 71.4%, 28.6%, respectively. 3. The maturation and fertilization rate of follicular oocytes, cultured in the TCM-199 medium supplemented with 5%, 10%, 15%, 20% FCS and hCG, HCG, $\beta$-estradiol were 76.0%~82.3% and 26.2%~70.0%, and those values were higher the supplementation of the hormone than the non-supplementation. 4. The fertilization and cleavage rate of the follicular oocytes, inseminated with spermatozoas of epididymis cauda, neat and frozen semen were 63.3%, 73.3%, 70.0% and 32.7%, 37.8%, 38.3, respectively. 5. The fertilization and cleavage rate of follicular oocytes, fertilized with capacitated spermatozoas by heparin, BFF and HIS methods were 70.0%, 53.8%, 34.2% and 38.3%, 23.1%, 17.1%, respectively. And the fertilization and cleavage rate were higher method of heparin than other methods.r methods.