• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.4
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• pp.268-276
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• 2007

Urban atmosphere may play as a harbinger for the future climate change with respect to temperature and $CO_2$ concentration. The Seoul metropolitan area is unique in rapid urbanization and industrialization during the last several decades, providing a natural $CO_2$ dome with increased temperature. This study was carried out to evaluate the feasibility of using the urban-rural environmental gradient in replacement of the IPCC mid-term scenario (after 30-50 years). For this, we measured atmospheric $CO_2$ concentration and air temperature at three sites with different degree of urbanization (Seoul, Suwon, and Icheon). Results from 11-month measurement can be summarized as follows: (1) The annual mean $CO_2$ concentration across 3 sites was in the order of Seoul (439 ppm) > Suwon (419 ppm) > Icheon (416 ppm), showing a substantial urban-rural environmental gradient. (2) The diurnal fluctuation in $CO_2$ concentration was greater in summer than in winter, showing the effect of photosynthesis on local $CO_2$ concentration. (3) The daily maximum $CO_2$ concentration was observed at 0500 LST in spring and summer, 0800 LST in autumn, and 0900 LST in winter, showing the sunrise-time dependence. (4) The observed hourly maximum $CO_2$ concentration averaged for the whole period was 446 ppm in Seoul at 0700 LST, while the minimum was 407 ppm in Suwon at 1500 LST. (5) Compared with the background atmospheric concentration of $CO_2$ in Anmyeon-do (377.4 ppm annual mean), $CO_2$ concentration of the study sites was higher by 14% in Seoul, by 10% in Suwon, and by 9% in Icheon. The observed $CO_2$ concentration in Seoul reached already 98% of the 2030-2040 projection (450 ppm) and 80% of the 2040-2050 projection (550 ppm) under the IPCC BAU scenario, showing a feasibility of using the $CO_2$ dome of Seoul as a natural experimental setting for the mid-term climate change impact assessment.

• Journal of Energy Engineering
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• v.29 no.1
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• pp.85-99
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• 2020

This article analyzes the influence of sectoral system of innovation(i.e. technological regime, market demand, networks, and institution) on innovative performances(i.e. product-, process-, organizational-, marketing-, and environmental- innovation) in Korean environmental industry, conducting a multiple regression analysis based on survey data from 201 Korean environmental companies. As the results, product innovation is positively influenced by internal technology accumulation and market demand response, while not affected by external knowledge utilization, market competition, networks among market and non-market agents, government support and regulation. Process innovation is positively influenced by internal technology accumulation, networks among non-market agents and regulation, but not by external knowledge utilization, market demand response, market competition, networks among market agents, and government support. While organizational innovation is positively influenced by internal technology accumulation, external knowledge utilization and regulation, it is not affected by market demand response, market competition, networks among market and non-market agents, and government support. While marketing innovation is positively influenced by internal technology accumulation, networks among non-market agents, and government support, it is not affected by external knowledge utilization, market demand response, market competition, networks among market agents, and regulation. Environmental innovation is positively influenced by external knowledge utilization and regulation, but negatively influenced by market competition. It is not affected by internal technology accumulation, market demand response, networks among market and non-market agents, and government support. Such results suggests the following policy implications. First, it is necessary to expand the sphere of relating markets through the application of convergence technology, new regulations, and overseas markets. Second, reinforcing ecosystems among environmental market agents through demand-linked joint R&D should be revitalized. Third, it is needed to strengthen more supporting policies rather than regulation. This article has the limitation of using the survey data. And further researches on the environmental sectoral system of innovation structure itself will be tried.

• Journal of Embryo Transfer
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• v.2 no.1
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• pp.36-46
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• 1987

The present work was designed to understand the mechanism of superovuiation and the cause of early embryo loss and Implantation failure in the superovulating immature female rats which were elaborated by a pituitary gland transplantation. A pituitary gland obtained from the orchidectomized rats was transplanted under the right kidney capsule of 28 day old female rats (PGT group) on the starting day of experiment which was designated as Day 2. The grafted pituitary glands were removed at 6h (RPGT 6h group), 12h (RPGT 12hgroup) and 24h (RPGT 24h group) after the transplantation. Control rats were treated with 41U PMSG on Day 2 (PMSG group). The estrous cycle and the levels of plasma progesterone and estradiol-17$\beta$ were observed on Day 0, Day 5, respectively. The implantation sites, the weights of ovary and uterus, and the number of corpora lutea were examined in all group on Day 8. The resuft obtained were summarized as follows: 1. The percentages of the number of the rats in proestrus and estrus were 93.0%, 82.6%, 0%, 90.7% and 89.5% in PMSG, PGT, RPGT6h, RPGT12h and RPGT24h group, respectively. The synchronization of estrus cycle was dchieved in all groups. 2. The mating rates of each group were 80.2, 75.0, 0, 56.4, 57.8% in PMSG, PGT, RPGT6h, RPGT12h, RPGT24h group, respectively. 3. The numbers of copora lutea on Day 8 were 47.1 i 4.9, 18.1 $\pm$0.5, 14.1 i 0.3 and 8.9 $\pm$ 0.3 in PGT, RPGT24h, RPGTl2h and PMSG group, respectively. There were signIficantly difference between all groups (P<0.05). 4. The numbers of implantation sites (18.1 +- 4.0) in PGT group on Day 8 were higher than those of PMSG (8.5 $\pm$ 2.5), RPGT 12h (9.8 i 0.2) and RPGT 24h group (10.8 i 0.2) (P<0.05). 5. The ovarlan weights in PGT (95.2 $\pm$ 14.3mgIlOOg BW), RPGT 12h (51.7 $\pm$ 0.6mgIlOOg BW), and RPGT24h (57.9 $\pm$ 0.9mg/l00g 8W) groups were significantly higher than those of PMSG group (30.4 $\pm$7.4mg/l00g BW) (P<0.05). 6. The uterine weights in PMSG (672.4 $\pm$ 4.7mg/l00g 8W), and PGT (660.7 $\pm$7.8mg/l00g BW) groupswere greater than those of RPGT 12h (403.0 $\pm$ 1.lmg/lOOg BW) and RPGT 24h (490.1 $\pm$ 0.9mg/l00g BW) group (P<0.05). 7. The plasma progesterone levels in PGT groups (15 lng/ml) on Day 5 were higher than those of PMSG (83ng/ml), RPGT 12h (S7ng/ml), RPGT24h (8lng/ml) group (P<0.05). 8. The plasma estradiol-17$\beta$ levels in PMSG group (lBSpg/ml) on Day S were higher than those of RPGT 24h (l3pg/ml) group (P<0.05). But estradiol-17$\beta$ levels in PGT and RPGT 12h group were too low to discuss.

• Parasites, Hosts and Diseases
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• v.34 no.1
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• pp.59-68
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• 1996

This study investigated the enzyme histochemical localization and characteristics of lactate (LDH) and malate dehydrogenase (MDH) related with the oxidation-reduction metabolism in the sparganum and adult of 5. erinacei. By enzyme histochemical assay, activity of LDH was strong in the tegument and subtegumental muscle layers of the adult and sparganum. Activity of MDH was strong in the tegument of the sparganum and subtegumental muscle layers of the adult. However it was weak in the tegument of the adult. By electrophoresis, 45 kDa band was major and common in LDH of adults and spargana. The 150 kDa molecule was the major and common band in MDH of adults and r -spargana (from experimentally infected rats) . By isoelectrofocusing, isoelectric points (Pl) or 4 MDH isogyme from adult worm were 6.0.6.5, 6.7 and 7.1, respectively. Pl 6.0 was the major band. The active range of pH for MDH was about pH 6-8 and the optimum pH was pH 7 The effective temperature on the MDH was about $30^{\circ}C$∼$50^{\circ}C$ and the optimum temperature was about 40℃ in spargana md adult worm. In the stability against heat, when MDH was heated at 85℃ for 10 seconds, the activity was denatured perfectly. Maximum activity or MDH was 19.4 unit in the s-sparganum (from snakes), 24.5 unit in the r-sparganum (from rats) and 108.0 unit in the adult worm. The maximum activity was higher in adults than in spargana. The present result showed us that the nutrients absorbed through the tegument were transferred into inner tissues and were utilized as the source of metabolism. According to the habitat of the parasite, the isozymes of LDH and MDH are activated differently, and by this different activation the sparganum and adult can adapt themselves to parasitic circumstances.

• Food Science and Preservation
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• v.13 no.6
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• pp.754-761
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• 2006

This study was to investigate the effect of chitosan-ascorbate (CA) prepared with different molecular weight (223, 746, 1110 and 2025 kDa) on the fermentation and quality of mul-kimchi, and also, the effect of the mul-kimchi juice fermented with 0.1% chitosan-ascorbate prepared with 2025 kDa chitosan (CA2025) on the serum lipids of rae fed with high cholesterol diet (HC). The mul-kimchi fermented in 0.1% CA2025 has lower turbidity, longer shelf-life, higher glucosamine content and SOD activity than those of control and the other treatments. In the animal experiment the HC-CA2025 and HC-2CA2025 groups which were administered 0.5 mL per 100 g body weight of mul-kimchi juice fermented with 0.1% CA2025 and administered the same volume of the juice concentrated 112 per nay fed for 5 week, respectively. The average body weight of the HC-CA2025 and HC-2CA2025 group was lower 6.9% and 8.4% than that of HC control group respectively. Total serum cholesterol contents of these groups were 88.33 and 85.00 mg/uL, which were 17.45% and 20.56% lower than HC control group respectively. While, HDL-cholesterol content of these groups were 7% and 23%, higher the LDL-cholesterol content were 13% and 26% lower than those of HC control group respectively. And also, though the atherogenic index, AST and ALT activities were not reached to normal control group, the values were remarkably lower than those of HC control group. This study indicates the possibility of utility for kimchi industry by adding chitosan-ascorbate, especially CA2025 showing not only quality enhancing and shelf-life prolongation but also improving serum lipids and atherogenic index in rats fed with high cholesterol diet.

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.409-417
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• 2001

The purpose of this study was to investigate the influence of light irradiation over self-priming adhesive on dentin bonding. After acid etching the exposed dentin, a self-priming adhesive (Prime&Bond$^{\circledR}$NT dental adhesive system Dentsply DeTrey, GmbH, Konstanz, Germany) was applied and light irradiation was done for 20 sec with regular intensity (600 mW/$\textrm{cm}^2$) in group I and for 3 sec with ultra-high intensity (1930 mW/$\textrm{cm}^2$) in group III. No light irradiation was done over self-priming adhesive in groups II and IV. Composite resin was added on the self-priming adhesive and irradiated for 40 sec with regular intensity (600 mW/$\textrm{cm}^2$) in groups I and II and for 3 sec with ultra-high intensity (1930 mW/$\textrm{cm}^2$) in groups III and IV. To see the effect of light curing time on dentin bonding, another 3 group specimens were prepared. Without light-irradiation over self-priming adhesive, added composite resin was irradiated for 3, 6, or 12 sec with ultra-high intensity light. After bonded specimens were stored in 37$^{\circ}C$ distilled water for 24 hours, shear bond strength were measured using a universal testing machine (4202, Instron, Instron Co., U.S.A.) and fractured surfaces were examined under a stereomicroscope (SZ-PT Olympus, Japan). Statistical analysis were done with one-way, two-way ANOVA and chi-square test. The results were as follows : 1. The shear bond strengths from the groups irradiated over self-priming adhesive were significantly higher than those from the groups without irradiation (p<0.05). 2. There was no significant shear bond strength difference between regular intensity light irradiation groups and ultra-high intensity ones (p>0.05). 3. There was no significant shear bond strength difference among various irradiation time groups with ultra-high intensity ones (p>0.05). 4. In stereomicroscopic examination of fractured surfaces, adhesive-cohesive mixed failure mode was mostly seen in all groups, and there was no significant difference in failure mode among groups (p>0.05).

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.199-211
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• 1994

Butachlor applied pre-emergence at 3.6kg ai/ha inhibited the growth and developments of shoot of barnyardgrass under dry condition, whereas rice was unaffected. Growth of rice and barnyardgrass under water condition was severely inhibited by treatment of butachlor but that of transplanted rice was not affected. The inhibition rate was higher under water condition, in broadcast rice and direct seeded rice than under dry condition, drilled rice and transplanted rice, respectively. The major anatomical response of stem of barnyardgrass seedling to butachlor under dry condition were partial reduction in thickness and collapse of leaf sheath, while not in rice. Broadcast rice on soil under water condition appeared reduction and constriction of leaf primordia thickness, and barnyardgrass formed tubular-like leaves and showed inhibited elongation of apical meristem. On the other hand, transplanted rice did not show these responses.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.38-46
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• 2005

To determine the actual hygienic status of domestic chicken meats sold in public markets (conventional markets and department stores), microbial contamination levels (Total cells, Coliforms and Staphylococcal cells) and zoonotic pathogens (Salmonella species, Campylobacter species, Listeria species, and Staphylococcus aureus) isolation tests were conducted. Chicken meats and eggs tested were collected from the conventional markets (Si-Jang) and department-stores located in Seoul and Kyung-gi regions in 1996. In total cells and coliforms contamination tests, chicken meats sold in department stores were much lesser contamination status than those of Si-Jang, but staphylococcal cells level was much more higher than that of conventional markets. Salmonella isolation frequency was investigated as $68.8\%$, but Campylobacter jejuni and Listeria monocytogenes isolation frequency were appeared both $64.0\%\;and\;63.3\%$. In case of eggs sold in public markets, one of S. gallinarum strain $(0.7\%)$ was isolated only on the egg-shell part among the four-hundred and fourty-six. In comparison with foreign imported chicken meats, there were no big differences in microbial contamination status. On the other hand, both Salmonella and L. monocytogenes were isolated only in the chicken wings from Korea and China, but not from U.S.A. This data suggest that more hygienic control system in order to produce the safe and hygienic chicken meats and eggs is need in our country as soon as possible.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1055-1061
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• 2007

Caesalpinia sappan L. is an indeciduous tree distributed in China, India, Miyanmar and Vietnam. Its heartwood has long been used in oriental folk medicines to treat diseases. In this study, antioxidative activities of Caesalpinia sappan L. and the effect of gamma irradiation on its chemical and biological properties were investigated. The ethyl acetate fraction (EtOAc fr.) of Caesalpinia sappan L. was irradiated with 100 kGy of gamma ray. The dark red color of EtOAc fr. was significantly (p<0.05) removed by irradiation (Hunter L and b values increased and a value decreased). The total phenolic content of EtOAc fr. was 865 mg/g and it was increased to 1195 mg/g by gamma irradiation. DPPH radical and superoxide anion radical scavenging activities and lipid peroxidation inhibitory activity of EtOAc fr. were very high and its activities were also increased by gamma irradiation. EtOAc fr. also inhibited the irradiation-induced DNA damage of lymphocyte as determined by comet assay. In conclusion, EtOAc fr. of Caesalpinia sappan L. extract showed high antioxidative activities in vitro. Furthermore, gamma irradiation on EtOAc fr. ameliorated the color and antioxidative properties. Therefore, it can be suggested that Caesalpinia sappan L. may be a good material for antioxidant function and gamma irradiation may be applied for the improvement of chemical and biological properties of Caesalpinia sappan L.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.18-28
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• 1991

The optimal pH of the extraction buffer was 7.5 considiering AChE stability and its buffer capacity when AChE was isolated and extracted from the housefly(Musca domesitca L.)and three other insect species with 0.01 M sodium phosphate buffer. Also, the optimal pH of the reaction buffer was 7.5 considering enzyme activity and its buffer capacity when AChE activity was measured with the substrate in 0.1 M sodium phosphate buffer. The Potter Elvehjem type homogenizer with Teflon pestle was used to homgenize the tissues. When preparing a AChE suspension by centrifuging the homogenate, 700 g supernatant of adult head for the housefly, 700 g supernatnat of 5th instar nymphal whole body for the brown planthopper, lipid-eliminated 10,000 g supernatant of 5th instar larval whole body for the diamondback moth, and 700 g supernatant of 4th instar larval head for the tobacco cutworm were considered satisfactory as enzyme sources in view of mass preparation, extraction efficiency and stability of enzyme activity during evaluation. When AChE suspensions of 4 insect species were stored at $-18^{\circ}C$, more than 90% of activity was maintained up to 3 weeks. Km values of AChEs of the housefly, the brown planthopper, and the diamondback moth were 0.042, 0.037 and 0.043 mM, respectively and AChE-specific substrate inhibition was observed at high concentration. Km value of the tobacco cutworm ChE was 1.15 mM and BuChE characteristics was observed, though further study is needed. The optimal substrate concentration for the AChE inhibition tests was 0.5 mM for the housfly, the brown planthopper, and the diamondback moth and 12 mM for the tobacco cutworm.