• The Journal of the Korean dental association
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• v.50 no.6
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• pp.304-311
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• 2012

Eruption of the teeth can be disturbed by crowding, ectopic eruption path, retention for pathologic condition of follicle and periodontal ligament, local disturbances in the innervation, and delayed eruption for overlying obstacles in the eruption path. Eruption disturbance of permanent posterior teeth is taken with diverse therapeutic approaches according to the patient age, cooperation of patient, tooth position and maturity, degree of impaction, clinical features, and repercussion on the neighboring teeth. However, delayed treatment usually results in less favorable outcomes. Therefore, In order to prevent this situation, periodically radiographic examinations during the early mixed dentition period and early diagnosis of eruption disturbances of permanent posterior teeth are recommended.

• Journal of the Korean Society of Tobacco Science
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• v.6 no.2
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• pp.179-184
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• 1984

This experiment was carried out to select the suitable burley varieties for paddy field. Two varieties, two $F_1$ hybrids and three $F_1$ hybrids with pale yellow line which were all early maturing were tested in the paddy field condition. The results were as follows. 1. Va 528 and all $F_1$ hybrids flowered 4-8 days earlier than Burley 21. 2. Leaf maturity among varieties and $F_1$ hybrids were not significantly different at first priming, but significant differences were detected from second to forth primings. (MS Ky 12x JB 7802-30)Fl and (MS Br 21 x L8)$F_1$ hybrids matured 3-5 days earlier than Burley 21. Pale yellow hyorids matured early, yielded high and were favorable in physical properties, but were low in quality. 4. Va 528 and (MS Br 21 x L8) $F_1$ hybrid showed earthy maturing, high yield and good quality compared with Burley 21. So two varieties were considered suitable for paddy field cultivation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.131-132
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• 2021

According to the domestic specification, the curing of the specimen for strength management used to determine the time of the mold deformity of the structure concrete in early spring and early autumn is cured in the field structure condition. However, when the seal curing is performed in the field, the temperature of the specimen is very low compared to the temperature of the actual structure, so the strength of the structure concrete predicted based on the strength of the specimen is much undervalued than the actual one, which causes the mold to be deformed. Therefore, this study analyzed the temperature history and compressive strength characteristics of the specimen for strength management through other sealing curing at 5℃ and concrete of the actual structure, and presented the most suitable curing method.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.11
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• pp.1684-1688
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• 2007

This study examined the caponization effects on the muscle characteristics (quality and quantity) of caponized male chickens fed before or after sexual maturity. Healthy and uniform Single Comb White Leghorn chickens were caponized at 3-week-old. Feeding was conducted until 16-week-old in trial 1 or from 12-week-old to 26-week-old in trial 2. Ten sham operated male chickens (Sham) were also assigned to each trial as the control group. Chickens used in both trials were housed in individual cages with each chicken representing one replicate. The results showed that early caponization (3-week-old) significantly increased (p<0.05) body weight and pectoral major muscle weight and percentage at 16-week-old compared to the Sham in trial 1. Caponization significantly increased (p<0.05) the protein content of the pectoral major muscle, but decreased (p<0.05) the ash content. Late caponization (12-week-old) significantly decreased (p<0.05) the ash content, myofibrillar ATPase activity and emulsification capacity of the pectoral major muscle in mature capons (26-week-old) compared to the Sham in trial 2. Early caponization (3-week-old) only increased the weight and protein content of the pectoral major muscle with decreased ash content in 16-week-old capons. Late caponization (12-week-old) showed no affects on pectoral major muscle quantity, while it decreased the ATPase activity and enhanced the emulsification capacity in mature (26-week-old) capons. Hence, the muscle quality improvement was shown as capons were fed to sexual maturity.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.1
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• pp.19-24
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• 2007

Covariance components and genetic parameters of weekly live body weight from hatching to six weeks of age and age of sexual maturation were estimated in a laying type Japanese quail line. The univariate and bivariate animal model analysis included hatching group and sex as fixed effects. Each trait was analysed with animal as random effect to fit the additive direct effect. Additional random effects incorporated in the models were changed according to the trait examined. The best model for a trait was chosen based on a likelihood ratio test, comparing the models with and without maternal additive genetic and maternal permanent environmental effects. Heritability estimates of live-weight at hatch and one to six weeks of age with their standard errors were 0.22${\pm}$0.088, 0.39${\pm}$0.099, 0.31${\pm}$0.086, 0.38${\pm}$0.056, 0.46${\pm}$0.055, 0.50${\pm}$0.059, and 0.56${\pm}$0.062, respectively. Direct heritability value of age of sexual maturation was moderate (0.24${\pm}$0.055). The variances due to permanent environmental effect of dam after one week of age and maternal genetic effect after two weeks of age were not important sources of variation. The correlations between direct and maternal genetic effects were negative and ranged from high to moderate values (-0.21 to -0.83). Among the weekly live weights, genetic correlations were generally high between not only successive but also early and late weightings. It suggests that selection for final weight may be based on early weight records. Genetic correlations between age of sexual maturation and live weights were low, favourable but had high standard errors. These results indicate that selection for high weight will potentially result in lower age of sexual maturation only with accurate determination of breeding values.

• Journal of the Korean Society of Costume
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• v.56 no.3 s.102
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• pp.81-90
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• 2006

The objective of the study is to review trends of clothing export in important countries of the world and thus to know the present stage of clothing export in Korea. For the purpose, changes of export amount, competitiveness and product life cycle were analysed in the countries from the 1960's to the 1990's. The results are as following: First, on the aspect of export amount, industrialized countries lost the lead to newly industrializing countries from the 1960's. Developing countries, as China, win the lead. Second, on the competitiveness aspect, industrialized countries lost competitiveness to newly industrializing countries before the 1960's. And newly industrializing countries were outpaced by China in the export competitiveness from the early 1990's. Third, on the aspect of product life cycle, industrialized countries go first through each period of product life cycle, introduction, growth, maturity and decline, and they all, excluding Japan, sustained period of Maturity for a long time. newly industrializing countries and developing countries go orderly through each period of product life cycle after industrialized countries. As to Korea, duration of each period was short. Specially characteristics of decline period appeared partly in the early 1990's. From the results, the theory of product life cycle, helping to explain changes in production and trade in new product lines, estimated to applicable to clothing export. The phenomena, Italy, Hong Kong and America sustain high competitiveness in the world clothing market for a long time, is needed to be studied carefully. The study about strong points in their clothing industries and competitiveness drive program be to influence Korean export policy in the future.

• Korean Journal of Veterinary Research
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• v.14 no.1
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• pp.1-7
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• 1974

Little work has been done on the changes in the blood picture occurring at different ages in cattle. In our country Kim (1963) and Jeong (1965) recorded the blood picture of mature Korean native cattle and, recently, Mun et al. (1974) has recorded the blood picture of Holstein cows. And a comprehensive survey of the blood picture of Korean native cattle has not been made. The object of the present investigation was to make good this deficiency, and to suggest standards for the blood picture of Korean native cattle at frequent intervals from birth to maturity. The cattle were kept under average farming conditions in this country. Observations were made at the following ages: at birth; 1, 2 and 4 days; 1, 2 and 4 weeks; 2,4,6 and 9 months; 1, 2 and 3 years of age. Blood samples were drawn from the jugular vein. Erythrocyte enumerations, concentration of hemoglobin in blood and hematocrit values were made in usual manner. Erythrocyte counts increased from $8{\times}10^6/mm^3$ during the first week to a level of $10{\times}10^6/mm^3$ at 2 months of age, showing steady state untill 6 months of age; it then fell to adult level ($8{\times}10^6/mm^3$) at 9 months of age. Concentration of hemoglobin in blood and hematocrit values were closely related to the changes of erythrocyte counts. The values increased from 10 g/100 ml and 31~35 ml/100 ml during the early life to 11 g/100 ml and 38 ml/100 ml at 2 months of age, showing steady state untill 6 months of age; these then fell to adult level (10 g/100 ml and 31~34 ml/100 ml) at 9 months of age for concentration of hemoglobin in blood and hematocrit values, respectively. Mean corpuscular volume and mean corpuscular hemoglobin showed a common pattern. The values were $42{\sim}43{\mu}m^3$ and 12.4 pg during the early life and fell a little to 6~9 months of age; these then increased to reach adult levels of $43{\mu}m^3$ and 12.6 pg for mean corpuscular volume and mean corpuscular hemoglobin, respectively. Mean corpuscular hemoglobin concentration was little affected with age.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.101-106
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• 1979

Present studies were carried out to get a basic information for biological control of soybean rod borer, Grapholitha glycinivorella Matsumura, causing main injury in soybean cultivation in Korea. 1474 native strains were cultivated in field to evaluate the pod borer damage. Pubescence density and color, maturity group, seed coat color, aphid and general leaf damage and seed damage by pod borer were investigated, and determined among their relationships. As another basic study for ecological control of insect, 6 leading varieties were planted on different planting date with 3 levels of plant spacing, on which pod borer damage and some related agronomic characters were studied. The results obtained one summarized as follows: Average injury of soybean pod borer was $5.2\%$ ranging $0-38\%$ in 1474 strains planted on 20 May. Non-significant correlations were found between pod borer damage and pubescence density and color, while pod borer damage closely related with maturity groupand aphid damage at $5\%$ level ofttests. Most severe damage was found in green seed coast color and maturity group V. Late and sparse plantings tend to have more damages to the pod borer than those of early and dense plantings. Pod setting date and period of pod maturing seemed related with pod borer damage. Bongeui and Chungbuk-baik cultivars were resistance to soybean pod borer, while Clark and Kumkang-daerip were susceptible in field tests.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.312-319
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• 2020

Precocious puberty (PP) is defined as the early development of secondary sexual characteristics (before the ages of 8 years in girls and 9 years in boys). The aim of this study is to identify characteristics of the dental maturity in girls with PP that discriminate them from normal healthy girls. This study included 99 girls aged 6 - 8 years with PP and 99 girls without past medical history of same chronological age (control group). The study was performed on 198 panoramic radiographs (99 PP girls, 99 control group girls). Demirjian method was used to evaluate the panoramic radiographs and determine dental maturity. Difference in dental maturity score and tooth formation stages between the two groups were analyzed. The PP group showed significant higher maturity score than control group. Among mandibular teeth, mandibular 2nd premolar and 2nd molar were significantly more mature in the PP group than control group. Logistic regression analysis showed that mandibular 2nd molar was only significant predictor for PP girls.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.4
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• pp.327-337
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• 1996

A field experiment was conducted at SNU Experimental Livestock Farm, Suweon in 1995 to determine effect of planting date on forage performance of wm hybrids of four different maturity groups. A split-plot design replicated three times was used, with com hybrids representing four maturity groups (115, 118, 121 and 125 days) being the main plots and planting dates (3124, 415, 415, 425, 515 and 5/15) the sub-plots. 1. Days to emergence and percent emergence from the March 24 planting were, on the average, 36 days and 58%, respectively, but those from the April 5 to May 15 planting averaged 12 days and 92%, respectively. 2. Plant and ear heights increased gradually as the dates of planting were delayed except the May 15 planting, however, percent ear was decreased as the dates of planting were delayed. There was a trend for the mean lodging percentage of the hybrids to be higher as the planting date was delayed. 3. The 115-and 118-day mediumearly maturing hybrids harvested on August 18 produced silages with a dry matter content between 27 and 30% at all planting dates except the May 15 planting, while the 121-and 125-day medium-late maturing hybrids produced silages with a dry matter wntent less than 27% regardless of any planting dates. 4. There were no significant differences in mean dry matter yield among the hybrids, but significant mean TDN yield differences were found. The 115-, 118- and 125-day hybrids had significantly higher mean TDN yield than the 121-day hybrid. There were significant differences in mean dry matter and TDN yields among the planting dates. The mean dry matter and TDN yields from the April 5, 15 and 25 plantings were significantly higher than those of other plantings, however, there were no significant differences in mean TDN yield among the April 5, April 15 and April 25 plantings. No significant planting date $\times$ maturity interactions were found for both the dry matter and TDN yields. 5. Mean stover NDF and ADF contents of the 115- and 118day hybrids were higher than those of the 121- and 125-day hybrids, but the reverse was true for mean stover IVDMD and RFV. Mean stover NDF an ADF contents increased with earlier plantings, but mean stover IVDMD and RFV increased when planting was delayed. Results of this experiment indicate that for corn planting in central and northern areas of Korea, early to mid-April may be the right time with the 115-to 118-day maturity hybrids when silage making before August 20 is taken into consideration.