• Development and Reproduction
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• v.10 no.1
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• pp.55-61
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• 2006

There is growing concern that dietary soy intake is associated with protection of breast cancer. However, questions persist on the potential adverse effects of the main soy constituent genistein(GS) on female reproductive physiology. In this study, we examined whether prepubertal exposure to GS affected on the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in female rats. GS(100mg/kg/day) was administrated daily from postnatal day 25(PND 25) to the day when the first vaginal opening(VO) was observed, and the animals were sacrificed on the day after VO occurred. Gross anatomy and tissue weight were compared to test the GS's effect on the cell proliferation. Furthermore, histological studies were performed to assess the structural alterations in tissues. Specific radioimmunoassay(RIA) were carried out to measure serum LH levels. To determine the transcriptional changes in progesterone receptors(PR), total RNAs were extracted from ovary and uterus and were applied to semi-quantitative reverse transcription polymerase chain reaction(RT-PCR). As a results, advanced VO was shown in the GS group(PND $31.2{\pm}0.6$) compared to the vehicle group (PND $35.3{\pm}0.7$). GS treatment significantly increased wet weight of ovaries and uteri compared to the vehicle group. Increased serum LH levels were also shown in the GS group. Graafian follicles and corpora lutea(CL) were observed only in the ovaries from GS treated animals. Similarly, hypertrophy of luminal and glandular uterine epithelium were found only in the GS group. Collectively, these effects were probably due to the estrogenic effects of GS. In the semi-quantitative RT-PCR studies, the transcriptional activities of PR in both ovary and uterus from GS-treated group were significantly higher than those from the vehicle group. The present studies demonstrated that acute exposure to GS, at levels comparable to the ranges of human exposure, during the critical period of prepubertal stage activates the reproductive system resulting precocious puberty in immature female rats.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.559-571
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• 2017

This study was conducted to determine the adhesive performances of plywoods affected by layering direction and the amounts of thermoplastic films. The face and back layers of veneer were hardwood species (Mixed light hardwood) and core layer veneer was radiata pine (Pinus radiata D. Don). Thermoplastic film used as adhesive were polypropylene (PP) film and polyethylene (PE) film. Thermal analysis and tensile strength were investigated on each films. As a result, the melting temperature of PP and PE films were $163.4^{\circ}C$ and $109.7^{\circ}C$, respectively, and the crystallization temperature were $98.9^{\circ}C$ and $93.6^{\circ}C$, respectively. Tensile strength and elongation of each films appeared higher on the width direction than length direction. Considering the characteristics of the thermoplastic films, the test for the amount of film used was carried out by layering film to the target thickness on veneer. The effecting of layering direction of film on plywood manufacturing was conducted by laminating in the length and width directions of the film according to the grain direction of veneer. Tensile-shear strength of plywood in wet condition was satisfied with the quality standard (0.7 MPa) of KS F 3101 when the film was used over 0.05 mm of PP film and over 0.10 mm of PE film. Tensile-shear strength of plywood after cyclic boiling exceeded the KS standard when PP film was used 0.20 mm thickness. Furthermore, higher bonding strength was observed on a plywood made with width direction of film according to grain direction of veneer than that of length direction of film. Based on microscopic analysis of the surface and bonding line of plywood, interlocking between veneers by penetration of a thermoplastic film into inner and cracks were observed.

• Journal of the Korean Society of Costume
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• v.36
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• pp.219-238
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• 1998

For the purpose of this Study, the situation of Korean costume properties in the collection of overseas museums was investigated through correspondence, interviews with their curators and persons in charge and survey. As results were made about the situation of museum science (conservation) and practical utilization of costume properties. So, the study result were drawn as follows : Krean costume properties unexplaind of 'Korean cultural Properties' could be found in the Metropolitan Museum of Art of New York(135 pieces), the Brooklyn Museum of New York(20 pieces), the Newark Museum of New Jersey(15 pieces), and the Victoria Albert Museum of London(100 pieces). Korean costume properties in the collection of over-seas museums mostly fall under the rang of period between the 19th century and the early 20th century and are classified into everyday clothing, wedding costume and armors for the most part. In 1900s, museum in several countries began to collected Korean cultural properties through foreign missionaries or diplomats as well as merchants or travellers in who bought Korean objects. Recently, scholars, traditional Korean costume designerss and diplomatic and consular offices in overseas have donated our Korean costume to many foreign museums. Korean costume properties were largely on display in the dependent display of folklore museums or in a part of exhibition gallery for Asian culture and there were the separate exhibition rooms in museums in the United Kingdom, Germany, Denmark, Austria, Japan and the United States America. But the size and level of display room for Korean cultural properties is one third as large as that for chinese or Japanese cultual properties. It was found in this study that the traditional Korean costume in the collection of overseas museums was largely recorded only as general items rather than given their proper names. The typical example of misnaming included bridal's Kimono for Wonsam(원삼) in the Metropolitan Museum of Art, Yeonroksaek-bumunsajeokori for Dangeui(당의) and Jissan-gryongwonmunsadurumagi for Kongdali(동달이) in the Okura collection of the Tokyo National Museum, and so on. And the Victoria Albert Museum modified the way of wearing Daenim(대님) and the National Museum of Ethnology in Osaka seemed to misplace the ornament of Keanggi(댕기) on Mubok(무복) and Josunjuk(조선족: Chinese-Korean) Museum also misplace hansam(한삼). On the one hand, the Newark museum of New Jersey mixed Chinese armor with the Korean one and the Photohraph of King Kojong(고종) with Chinese one. It is corrected to publish and disseminate the book concering Korean costume in order to inform foreign museums of thed proper names and wearing method of our traditional costumed. The repair of costume before cleaning in the process of conservation treatment can prevent damage likely to occur as the properties of fiber itself are weakened in liquid. It is recommended that western 8-figure stitch and tacking stitch is added to Korean traditional stitching method. Museums in the U.S.A and the U.K are concerned about the aftermath of cleaning it-self, specially conservation treatment may exert on remains and predominantly use the vacuuming method to remove dust or bits of straw before the exhibition beings. But in case of Korea, the dry cleaning and wet cleaning method are used according to the nature and state of a sample costume. This comprehensive cleaning method is gradually developing scientifically but it is expected that those concerned will make a chemical analysis of the solvent to be used and also the more precise test of costume properties will be conducted before cleaning them. A partial study was made here because the scope of study was too broad and vast. It is expected that more studies will be conducted concerning our costume culture under the long-term plan and active support at the government level.

• Development and Reproduction
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• v.10 no.2
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• pp.147-154
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• 2006

Phthalates such as di(2-ethyl hexyl)phthalate(DEHP) are industrial chemicals with wide-ranging human exposures because of their use in plastics and other common consumer products. Consequently, their adverse effects as endocrine disruptor in the reproductive physiology of both laboratory rodents and human have been studied extensively. The present study was undertaken to examine whether prepubertal exposure to DEHP affects on the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in female rats. DEHP(100mg/kg/day) was administered daily from postnatal day 25(PND 25) through the day when the first vaginal opening(VO) was observed, and the animals were sacrificed on the next day. Gross anatomy and weight of reproductive tissues were compared to test the DEHP's effects on the cell proliferation. Furthermore, histological studies were performed to assess the structural alterations in the tissues. Specific radioimmunoassay was carried out to measure serum LH levels. To determine the transcriptional changes in progesterone receptor(PR), total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction(RT-PCR). As a result, delayed VO was shown in the DEHP group(PND $37.3{\pm}0.7$) compared to the control group(PND $35.3{\pm}0.7$; p<0.05). DEHP treatment significantly decreased the wet weight of ovaries and uteri compared to the control group(p<0.05). Interestingly, elevation of serum LH levels was shown in the DEHP group(p<0.05). Graafian follicles and corpora lutea were observed only in the ovaries from the control animals. Numerous primary, secondary follicles and small atretic follicles were observed in the ovaries from DEHP-treated animals. Similarly, hypotrophy of luminal and glandular uterine epithelium was found in the DEHP-treated group. These effects were probably due to the inhibitory effects of DEHP on the synthesis and secretion of estrogen from granulosa cells. In the semiquantitative RT-PCR studies, the transcriptional activities of PR in both ovary(p<0.05) and uterus(p<0.01) from DEHP-treated animals were significantly lower than those from the control animals. The present studies demonstrated that the acute exposure to DEHP during the critical period of prepubertal stage could inactivate the reproductive system resulting delayed puberty in female rats.

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.353-360
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• 2016

Effect of heavy metals(Cd, Cu, Zn) on the survival and population growth rates(PGR) of marine rotifer, Brachionus plicatilis were examined. B. plicatilis were exposed to Cd, Cu and Zn for 24 h to determine their survival and 72 h to determine their PGR. Survival rates in the control groups were greater than 90%. They were decreased with increasing concentrations of Cd, Cu and Zn. Survival rates were reduced in a concentration-dependent manner. Significant reduction in survival rates after exposure to Cd, Cu and Zn at concentration greater than 40.00, 0.13 and $10.00mg\;L^{-1}$, respectively. PGR in the control groups were greater than 0.50. They were decreased with increasing concentrations of heavy metals. PGR were reduced in a concentration-dependent manner. Significant reduction in PGR after exposure to Cd, Cu and Zn occurred at concentration greater than 12.5, 0.06 and $1.00mg\;L^{-1}$, respectively. The order of heavy metal toxicity based on PGR was Cu>Zn>Cd, with $EC_{50}$ (50% Effective Concentration) values of 0.12, 6.15 and $21.41mg\;L^{-1}$, respectively. The lowest-observed-effective-concentrations(LOEC) of PGR after exposure to Cd, Cu and Zn were 12.50, 0.06 and $1.00mg\;L^{-1}$, respectively. The No-observed-effective-concentrations(NOEC) of PGR after exposure to Cd, Cu and Zn were 6.25, 0.03 and $0.01mg\;L^{-1}$, respectively, in marine ecosystems have toxic effects on PGR of B. plicatilis. These results suggest that the PGR of B. plicatilis are useful tool to assess the effect of heavy metals on primary consumers in marine natural ecosystems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.643-650
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• 2007

It has been known that Samultang has positive effects on blood circulation and erythrocyte formation. Samultang was composed of four ingredients, Angelica gigas Nikai, Rahmanniae Radix Preparata, Paeonia lactiflora Pallas, and Cnidium officinale Makino. Five types of bread were prepared by replacing water with Samultang for dough proportionally. Control (C) did not have Samultang and the other four experimental bread contained Samultang: S-I (25% of water was substituted by Samultang), S-II (50% substituted), S-III (75% substituted), and S-IV (100% substituted). Moisture, protein, and ash contents of Samultang were $97.34{\pm}0.11%,\;0.42{\pm}0.04%,\;and\;1.40{\pm}0.16%$, respectively. Replacing water with Samultang decreased pH and increased significantly wet gluten content of the dough. Substitution of Samultang for water incremented redness and yellowness of the dough and bread and increased hardness. It also raised the contents of ash and protein. Although it was not significant, in addition, moisture loss of the bread during storage seemed to be lessened by replacing water with Samultang. However, total volume and specific loaf volume of the bread, baking loss rate, and the other textural characteristics except hardness were not affected by substituting water with Samultang. Due to the above results, sensory evaluation of volume and gumminess of the bread were improved significantly by substituting Samultang for water. The bread replaced 25% of the water with Samultang was ranked as the best by the test of sensory evaluation. These results imply that adding Samultang instead of water to dough for bread might bring positive effects on quality characteristics of the bread without any adverse influences. Therefore, it might be worth developing functional bread using Samultang.

• Research in Plant Disease
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• v.23 no.2
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• pp.159-167
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• 2017

This study was conducted to evaluate the control efficacy of the organic farming materials on cucumber scab caused by Cladosporium cucumerinum PT1 (KACC 48094). The antifungal activities in vitro as well as the suppressive effect of 43 organic farming materials on the spore germination and germ tube growth by inoculating spore suspension on cucumber seedlings in vivo were investigated. Thirteen organic farming materials inhibited the mycelial growth of C. cucumerinum and nine of these were microbial agents. In the screening using cucumber seedlings, six organic farming materials were very effective with control efficacy value of 90%. Among them, Bacillus amyloliquefaciens M27 provided suppressive effect on both mycelial growth and spore germination against cucumber scab. Finally, nine organic farming materials were selected to test the protective and curative effects, and all chosen organic farming materials significantly suppressed disease incidence when applied in the preventive action, in comparison with the curative action. Especially, Bordeaux mixture I and III gave excellent protective control efficacy with control values of 96.7% and 73.3%, respectively, whereas its curative control effect was significant low. Among these, only Thymus quinquecostatus+Sophora extract showed curative activity, although the control value was as low as 50%. This study suggests that cucumber scab can be controlled by some organic farming materials in the farmhouses under comparatively cold and wet condition and protective treatment is more important and efficient.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.1
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• pp.4312-4322
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• 1977

In order to investigate the effect of the water content and the accelerated curing on the strength of the soil-cement mixtures, laboratory test of soil cement mixtures was performed at five levels of water content, four levels of accelerated curing temperatures, three levels of normal curing periods, and six levels of accelerated curing time. Also this study was carried out to investigate the effect of grain size distribution of 21 types of soils on the strength of soil-cement mixtures at four levels of cement content and three levels of curing time. The results are summarized as follows: 1. Optimum moisture content increased with increase of the cement content, but maximum dry density was changed ununiformly with cement content. Water content corresponding to the maximum strength was a little higher than the optimum moisture content along the increase of cement content. 2. In molding the specimens with the optimum moisture content, the maximum strength appeared at the wet side of the optimum moisture content. 3. According to increase of curing temperature as 30, 40, 50, and 60$^{\circ}C$, unconiiend compressive strength of soil-cement mixtures increased, the rate of increase at the early curing period was large, and approximately 120 hours was suifficient to harden soil-cement mixtures completely. 4. The strength of soil-cement mixtures at the curing temperature of 10$^{\circ}C$ decreased at the rate of 30 to 50 percent than at the curing temperature of 20$^{\circ}C$, and the strength of soil-cement mixtures at the curing temperature of 0$^{\circ}C$ increased a little with increase of curing time. 5. Although the strength of soil-cement mixtures seemed to be a little affected by the temperature difference between day time and night, it was recommended that reasonable working period was the duration from July to August of which average maximum temperature of Korea was approximately 30$^{\circ}C$. 6. Accelerated curing time corresponding to the normal curing time of 28-day was shorten with increase of curing temperature, also it was a little affected by the cement. Accelerated curing time that the strength of soil-cement mixtures for the cement of 9 percent and the curing temperature of 60was shorten with increase of curing temperature, also it was a little affected by the cement. Accelerated curing time that the strength of soil-cement mix- tures for the cement of 9 percent and the curing temperature of 60$^{\circ}C$ was 45 hours at the KY sample, 50 hours at the MH, 40 hours at the SS, and 34 hours at the JJ respectively. 7. Accelerated curing time was depended upon the grain size distribution of soil, it decreased with increase the percent passing of No. 200 sieve. 8. Relationship between the normal curing times and the accelerated curing times showed that there was a linear relationship between them, its slope decreased with increase of curing temperature. 9. The most reasonable soil of the soil-cement mixtures was the sandy loam which was a well graded soil. Assuming the base of road requiring 7-day strength of 21 kg/$\textrm{cm}^2$ being used, the soil-cement mixtures could be obtained with adding 6 percent of cement in such a sails S-7, S-8, S-9, S-10, S-11, S-12, S-13. 10. The regression equation between the 28-day and the 7-day strength was obtained as follow; q28=1.12q7,+6.5(r=0.96).

• Development and Reproduction
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• v.11 no.3
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• pp.245-251
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• 2007

Vinclozolin(VCZ), a systemic dicarboximide fungicide, has been used in the control of diseases caused by microorganism of some species in fruits, vegatables and ornamental plants. Although VCZ itself is a very weak antagonist for androgen receptor binding, both melabolites M1 and M2 are effective antagonists. The present study was undertaken to examine whether prepubertal exposure to VCZ affects on the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in female rats. VCZ(10 mg/kg/day) was administered daily from postnatal day 21(PND 21) through the day when the first vaginal opening(V.O.) was observed. Gross anatomy and weight of reproductive tissues were compared to test the VCZ's effects on the cell proliferation. Furthermore, histological studies were performed to assess the structural alterations in the tissues. To determine the transcriptional changes in progesterone receptor(PR), total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction(RT-PCR). As a result, delayed V.O. was shown in the VCZ group(PND $34.00{\pm}1.22$) compared to the control group(PND $38.20{\pm}1.92$; p<0.01). VCZ treatment significantly decreased the wet weight of ovaries and uteri compared to the control group(p<0.01). Graafian follicles and corpora lutea were observed only in the ovaries from the control animals, while numerous primary, secondary follicles and small atretic follicles were observed in the ovaries from VCZ group. Similarly, hypotrophy of luminal and glandular uterine epithelium was found in the VCZ group. In the semi-quantitative RT-PCR studies, the transcriptional activity of PR in ovary(p<0.01) from VCZ group were significantly lower than those from the control group while in uterus were similar compared with the control group. The present studies demonstrated that the acute exposure to VCZ during the critical period of prepubertal stage could inactivate the reproductive system resulting delayed puberty in female rats.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.1-10
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• 1982

Degree of grain shattering which is of varietal character is an important determinant for the magnitude of field loss of grains during harvest and threshing. Seven Indica \times Japonica progeny varieties and four Japonica varieties were subjected to measurements of tensile strength of grains, degree of grain shattering when panicles were dropped at 1.5m above concrete floor, and moisture content of grains (wet basis) during a period 35 to 63 days after heading. In addition, two varieties were tested for the relation of tensile strength of grains to the magnitude of field loss of grains in actual binder harvest. The 11 varieties differed conspicuously in tensile strength of grains and the degree of grain shattering: the weakest average tensile strength of grains of a variety was about 90g and the strongest about 250g with varying standard deviation of 30 to 60g. Three Indica \times Japonica varieties and one Japonica variety shattered I to 30% of the grains under the falling test. The threshold tensile strength of grains allowing grain shattering was estimated to be 180g on average for a sampling unit of 10 panicles, but only the grains having tensile strength weaker than 98g within the samples shattered. A decrease in average tensile strength by 10g below the threshold value corresponded to an increase of 3 to 5% in grain shattering. Most varieties did not change appreciably the tensile strength of grains and degree of grain shattering with delay in time of harvest and showed a negative correlation between the tensile strength and the moisture content of grains. The average tensile strength of grains was negatively correlated linearly with field loss in binder harvest. The average tensile strength for zero field loss in binder harvest was estimated to be 174g and a decrease in the average tensile strength by 10g corresponded to an increase of 40kg per hectare in field loss of grains. Instead of the average tensile strength of grains, the percentage of grains having tensile strength weaker than 100g is recommended as a criterion for the estimation of field loss of grains during harvesting operations as well as a basis of variety classification for grain shattering, since the standard deviation of tensile strength of grains varies much with variety and time of harvest, and individual grains having tensile strength stronger than 98 did not shatter practically.