• Korean Journal of Animal Reproduction
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• v.4 no.1
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• pp.75-82
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• 1980

This experiment was carried out to improve a simple and effective procedure of egg transfer which is considered to be the most useful technique for the improvementand proliferation of domestic animals. Several experiment procedures such as superovulation, surgical recovery of ovulated egg, in vitro capacitation of ejaculated spermatozoa, in vitro fertilization and culture of embryo were conducted. The results obtained in this experiment were summarized as follows: 1. In rabbits treated with PMS in combination with estradiol and HCG, 10 to 43 eggs were obtained in one rabbit and the average ovulation number of 20 rabbits was 21 eggs. 2. Six to 24 eggs (average 13 eggs) were recovered from the removed oviducts by the methods of flushing technique and the average recovery rate of 20 rabbits was 61.9 percent. 3. Most rabbit spermatozoa ejaculated by artificial vagina were capacitated in vitro by the culture of the spermatozoa with PBI medium at 37$^{\circ}C$ for 4 hours after removal of seminal plasma. 4. Normal fetilization following in vitro fetilization was observed in 88 (42.7%) of 206 eggs. 5. The number of eggs developed to 2-, 4-, and 8-cell stage following in vitro culture with PBI medium at 37$^{\circ}C$ was 26 (70.3%), 20 (54.1%) and 17 (45.9%) of 37 eggs used for in vitro culture.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.1
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• pp.27-33
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• 2003

This study was conducted to determine the changes of nitrogen compounds in lamina and midrib during the curing process with the different curing methods, such as priming and stalk-cut curing. After KB 108 burley tobacco was cultivated by the different fetilization levels such as standard and 20% higher, only the tips and leaf were harvested. Though the contents of total alkaloid and total nitrogen were similar in lamina, midrib showed a very low contents of those components by the different curing method and fertilization levels. The content of nitrate-nitrogen in lamina increased during a middle of curing process, and then these compound was decreased during an end of curing process by stalk-cut curing method. Nitrate-nitrogen contents in the lamina by the priming curing showed a high level caused by rapid drying process during an end of curing process. That component in midrib was 5-6 times higher than that of lamina. The contents of ammonia-nitrogen in the lamina and midrib were increased during a curing process. Though those amount in tips showed a similar by a different fetilization and curing method, midrib of stalk-cut curing showed a slow increasing during a curing process.

• Journal of Embryo Transfer
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• v.7 no.1
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• pp.41-47
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• 1992

1. In vitro system, LR and FSR accelerated and facilitated meiotic progression, and LH selectively improved cytoplasmic maturation which is required to promote the formation of a male pronucleus. 2. Caffeine (2mM) in the fetilization medium was required not only for inducing zona penetrating ability of boar also for developing to the male pronucleus of the penetrat- ing spermatozoa in vitro. 3. The germinal vesicle (GV)stage was observed for the first 17.6 hr;germinal vesicle break-down (GVBD)stage between 17.6~26.4 hr ;metaphase I (M-I)from 26.4 - 30. 9hr;anaphase I(A-I)ranged from 30. 9~33.4hr;telophase I(T-I) at 33.4~34.4hr; and metaphase II(M-II) at 34.4-48hr. 4. The addition of 10%(v /v) pig follicular fluid (pFF) to maturation media significantly increased the rate of nuclear maturation of pig oocytes (p<0.01), whereas the rate of nuclear maturation of pig oocytes among three different media did not differ. 5. The presence of a primary culture of POEC promotes in vitro development of early cleavage stage pig embryos.

• Journal of Plant Biology
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• v.37 no.1
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• pp.1-8
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• 1994

The effects of fetilization on the structure and function of an early successional Miscanthus sinensis grassland were investigated in an old-field ecosystem at Honjo city, Saitama Prefecture, Japan from 1981 to 1982. Compared to control plot, life form composition of treatment plot was characterized by a decrease of phanerophytes and an increase of hemicryptophytes. Fertilization had a beneficial effect on the growth in aboveground phytomass of M. sinensis, the dominant species. However, it did not cause a change in the total number of stems of M. sinensis. Annual increment of patch diameter of M. sinensis was estimated to be 6-8 cm on an average and there was no significant differecne in the growth rate of patch size between fertilized and nonfertilized plots. To estimate the aboveground phytomass of M. sinensis, several non-destructive parameters were examined. As a result, the patch size showed a high correlation with aboveground phytomass. Thus the patch size was suggested to be most applicable to its estimation. Diversity indices based on phytomass data of component species were increased slightly by fertilizatin, because relative dominance of some other species, especially of Artemisia princeps increased, while that of M. sinensis decreased. Fertilizer application resulted in a decrease in the total number of species.

• Journal of Korea Foresty Energy
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• v.24 no.1
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• pp.13-27
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• 2005

In order to design new fertilizers for forests, seedlings of Pinus densiflora, Larix leptolepis Betula platyphylla var. japonica, and FQuercus acutissima were treated with different fertilizers, and nutrient concentrations in seedling components were analyzed. In general, nitrogen (N) and phosphorus (P) concentrations in seedling components increased after N and P application. Potassium (K) concentration in seedling components of Pinus densiflora and Quercus acutissima increased after N, P and K application. However, there were no significant changes in calcium (Ca), sodium (Na) and magnesium (Mg) concentrations. Nitrogen and P concentrations in seedling components increased with the amount of solid combination fertilizer and UF combination fertilizer. Potassium concentration for Pinus densiflora and Na and Ca concentrations for Larix leptolepis also increased with the amount of combination fertilizers. However, nutrient concentrations in seedling components showed no significant changes with different combination fertilizers.

• Journal of The Korean Society of Grassland and Forage Science
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• v.3 no.2
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• pp.58-66
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• 1983

This experiment was carried out to investigate the effects of the nitrogen rates and cutting heights on the appearance dry weight and death of new bud (branch and tiller) of sorghum-sudangrass hybrid (Sorghum bicolor (L.) Moench). The cultivar used in the present study was Pioneer 988. The experiment was arranged as a split plot design and undertaken in the Experimental Livestock Farm of Agriculture Coll., Seoul Nat'l Univ. in Suweon, 1981 and 1982. The results obtained are summarized as follows: 1. The appearance and death of branch and tiller were not influenced with high nitrogen fertilization. 2. The frequency of the branching was decreased as the low stubble height, and the rate of the tillering was decreased in the high stubble height. 3. The yield of forage mostly depended on the tiller regardless of cutting height, and minor portion of the yield was resulted from the branch. 4. The low cutting height resulted in the increased number of dead bud (p<0.05).

• Korean Journal of Health Education and Promotion
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• v.1 no.1
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• pp.57-71
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• 1983

Sex education is necessary for the youth that they should have an adequate sexual knowledge, attitudes and behaviors in their adolescent period. Four major objectives of this study are as follows; 1. To know the level of sexual knowledge of commercial girl's high school students in Seoul. 2. To know their actual state for the attitudes and behaviors toward sex. 3. To compare the sexual knowledge, attitudes and behaviors of day time school students with those of night time school students. 4. To compare the factors associated with their sexual knowledge, attitudes and behaviors with the individual level. Data were collected on 986 students in Seoul from April 1 to April 10, 1983. As the result of this survey, the following conclusions were obtained. 1. The level of sexual knowledge. (1) The level of knowledge of day time high school students about the physiology of female and pregnancy is shown higher than those of night time students. 64.2% of the respondents are aware of the organ producing ovum. 56.4% the ovulation period. 95.6% the cause of pregnancy. 74.5% the pregnantable period and 12.7% the place of fetilization. (2) Out of 986 respondents. 71.8% knew about contraceptive method correctly, and day time school students knew litter better than night time school students, by showing 73.9% and 69.7% respectively. They knew about contraceptive method with 'oral pills'. 'menstrual cycles', 'condoms'. and 'loops' in the same order. 3) Kinds of veneral disease was correctly known by 37.9%. Day time students knew much better than night time school students. by showing 67.8% and 7.9%. respectively. Transmission method of veneral disease was correctly known by 28.3%. Day time students knew much better than night time students, by showing 51.2% and 5.3%, respectively. (4) The major information source of sexual knowledge was 'book and magazine' (39.9%) and 'friends' (27.4%). 2. Actual state of attitudes and behaviors toward sex. (1) Out of 986 respondents, 84.0% answered that premarital purity should be kept. (2) Out of 986 respondents, 60.8% had an acquaintance of the opposite sex. 45.2% of students with opposite sex reported introduction of their friends as the main channel of making an acquaintance of the opposite sex. (3) Of those who responded to this study 13.8% reported having masturbation, 21.5% kissing, 6.2% petting and 3.7% sex intercourse. (4) 64.8% had sexual problems, which was mensturance (27.2%), aquaintance of the opposite sex (25.4%). The main method to solve the problems were consultation with 'friends' and 'books and magazine' percentage being 39.1% and 30.8%, respectively, whereas very small students discussed with 'teachers' and 'parents' percentages being 0.3% and 5.9%, respectively. (5) Out of 986 respondents, 62.2% had experience in educating about sex, the percentage of day time school was higher than that of night time school. (6) 88.2% of students wanted sex education in school, which were 'general information about sex' (35.4%), 'sexual morality and solution of sexual desire' (18.5%), 'aquaintance of the opposite sex' (13.3%) and 'marriage and role of man and woman' (12.4%) in the same order. They wanted to be instructed about sexes in the lecture of physical education, home economics, biology, military training (59.9%), regular curriculum (17.5%), special lecture (16.9%) and by the counselor or school nurse (5.7%). 3. Analyse concerning the factors about the knowledge, attitudes and behaviors. (1) The better school record was, the higher the level of sexual knowledge. (2) Those who have the religion considered the permarital purity more important than those who have not, the percentage showing 86.7% and 80.7%, respectively. (3) The result of dyad analysis of making acquaintance of the opposite sex in the friendship network showed that a high index of the acquaintance of the opposite sex tends to be a high adoption of making one at the individual level in the group, while the low index tends to be a low adoption of making one in the group.