• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.679-683
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• 2006

The effects of dried and fermented guava (Psidium guajava L.) leaf extracts on blood glucose levels were investigated in low-dose streptozotocin(STZ)-induced diabetic mice. Fermented guava leaf extract (500 mg/kg/day) significantly decreased the fasting blood glucose levels after 2-4 weeks of treatment and improved the impaired glucose tolerance in STZ-induced diabetic mice. On the other hand, dried guava leaf extract lowered the blood glucose levels and improved glucose tolerance two weeks after treatment, but exacerbated STZ-induced high blood glucose levels three and four weeks after treatment. Histological and immunohistochemical observation showed that fermented guava leaf extract treatment improved STZ-induced pancreatic beta-cell damage, but dried guava leaf extract did not affect the damage to the beta-cells. These results suggest that fermented guava (Psidium guajava L.) leaf extracts improve the hyperglycemia by protecting the pancreatic beta-cells hom damage in STZ-induced diabetic mice.

• Advances in Traditional Medicine
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• v.6 no.1
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• pp.12-20
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• 2006

Some natural products are able to inhibit radiation effects and exert an antitumor effect with fewer adverse reactions; however, their antitumor effects are less than those of widely-used synthetic drugs. Propolis is a natural material that has been attracting attention, and we extracted this material with water and investigated the effect of continuous propolis administration on radioactivity-induced reduction of hemocytes, in addition to the antioxidant and antitumor effects of propolis. Following a 1-week adjustment period, water-soluble propolis was administered intraperitoneally to male ICR mice at a dose of 100 mg/kg every other day for 2 weeks. Following administration, 2 Gy whole-body irradiation was performed and the counts of leukocytes, lymphocytes, and granulocytes and monocytes in the peripheral blood were determined 1, 3, 7, 15 and 30 days after irradiation. These cells were considered since they are closely associated with immunity to radioactivity. In a second experiment, water-soluble propolis was similarly administered to the mice for 2 weeks after a 1-week adjustment period, and 2 Gy whole-body irradiation was performed. The antioxidant effects in hemocytes were then investigated using 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH), a radical generator. In a third experiment, $1\;{\times}\;10^6$ Sarcoma-180 cells were inoculated into the right thigh of mice, which were divided into four groups: control, water-soluble propolis-treated, 6 Gy irradiated and water-soluble propolis-treated + 6 Gy irradiated groups, and changes in tumor size were measured for 20 days. Statistical analysis was conducted using ANOVA for multiple groups. In the three experiments, administration of water-soluble propolis inhibited the reduction of hemocytes caused by whole-body irradiation, showed antioxidant effects against radioactivity, and inhibited tumor growth, respectively. In conclusion, our data suggest that the antioxidant effect of watersoluble propolis inhibits hemocyte reduction caused by whole-body irradiation and enhances immunological inhibition of tumor growth.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.454-460
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• 2009

Phyllanthus urinaria was an important species in Korea and distributed in all around of Korea. The roots and stems of this plant have been used for natural medicine for the treatment of diabetes, the hepatitis B virus and disturbances of the kidney and urinary bladder. Production of adventitious roots in P. urinaria by in vitro cultures could be used as alternatives materials. Shoot and root segments from P. urinaria seedling were cultured on Murashige and Skoog (MS) medium supplemented with 3.0 mg/L IBA and 30 g/L sucrose. After 4 weeks of culture, the highest induction of adventitious roots was obtained from the shoot part. Frequency of adventitious root formation on medium with various kinds of auxins (IAA, NAA, 2,4-D, and IBA) and various concentrations of IBA (0, 0.1, 0.5, 1.0, 3.0, and 5.0 mg/L) was tested. The maximun induction of adventitious root was obtained on medium with 0.5 mg/L IBA. In liquid culture, growth of root was best on medium supplemented with 30 g/L sucrose. Adventitious roots were cultured in 5 L bioreactor containing 1/2 MS medium supplemented with 0.5 mg/L IBA and 30 g/L sucrose and mass-production of adventitious roots was successfully achieved. These results revealed the first attempt for the production of adventitious roots in P. urinaria.

• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.7-13
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• 2010

This experiment was conducted to establish the micropropagation of Calanthe discolor through multiple shoot formation from the culture of leaf, corm and root explants. Frequency of adventitious shoot formation from leaf explants was higher than those of corms and root explants. Frequency of adventitious shoot formation on medium with various concentrations of BA (0. 1.0, 3.0, and 5.0 mg/L) and NAA (0, 0.1, 0.5, and 1.0 mg/L) was tested. The maximun induction of adventitious shoot was obtained on half strength Murashige and Skoog (MS) medium supplemented with 3.0 mg/L BA and 1.0 mg/L NAA after 6 weeks of culture. Multiple shoots were transferred onto half strength MS medium with various concentrations of GA3 (0, 0.1, 0.5, 1.0, 3.0, and 5.0 mg/L). The number and length of multiple shoots on medium were highest on medium with 3.0 mg/L GA3. All the adventitious shoot grew well and rooted on half strength MS medium with 3.0 mg/L NAA. The plantlets were acclimatized up to 100% on sand with TKS-II or pearlite with TKS-II.

• KSBB Journal
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• v.19 no.6 s.89
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• pp.457-461
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• 2004

DO-stat fed-batch cultures of Agaricus blazei were carried out using various feeding solutions, for the production of mycelial biomass and exopolysaccharides (EPS). It was observed to be more effective to use a feeding solution containing both carbon and nitrogen sources than that containing only carbon source. The best result was obtained when a feeding solution containing 450 g/l glucose, 60 g/l yeast extract, 30 g/l soytone peptone was used. The maxium mycelial biomass and EPS concentrations were 36.5 g/l and 10.9 g/l, respectively, at 100 hours of cultivation. The mycelial and EPS productivities were 0.37 g/l-h and 0.11 g/l-h, respectively. As compared with the batch culture, the mycelial biomass concentration and its productivity were 6.0- and 2.2-folds increased, respectively. The EPS concentration and its productivity were increased by 4.7 times and 1.8 times, respectively.

• Applied Chemistry for Engineering
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• v.34 no.1
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• pp.80-85
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• 2023

New yellow quinoline-dione dye derivatives were designed and synthesized for use in image sensor color filters. The synthesized compounds have a basic chemical structure composed of quinoline and dione groups. New materials were evaluated on the basis of their optical and thermal properties under conditions mimicking those of a commercial device fabrication process. A comparison of their related performances revealed that, between the two prepared compounds, 2-(3-hydroxyquinolin-2(1H)-ylidene)-1H-indene-1,3(2H)-dione (HQIDO) exhibited the superior performance as an image sensor color filter material, including a solubility greater than 0.5 wt% in propylene glycol monomethyl ether acetate solvent and a high decomposition temperature of 298 ℃, respectively. The results suggest that HQIDO can be used as a yellow dye additive in an image sensor colorant.

• Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.26-35
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• 2010

In our previous study, we preliminarily demonstrated that Celluclast and Neutrase extracts exhibited the strongest $H_2O_2$-scavenging activities among five carbohydrases (Viscozyme, Celluclast, Termamyl, Ultraflo and AMG) and five proteases (Kojizyme, Alcalse, Flavourzyme Protamex and Neutrase) extracts. Thus, Celluclast and Neutrase extracts were selected for use in further experiments and were separated into four different molecular weight fractions (<5, 5-10, 10-30 and >30 kDa). Among them, the 5-10 kDa fraction showed the highest $H_2O_2$-scavenging activity. The 5-10 kDa fraction also strongly enhanced cell viability against $H_2O_2$-induced oxidative damage. Furthermore, the fraction reduced the proportion of apoptotic cells induced by $H_2O_2$, as demonstrated by decreased sub-G1 hypodiploid cells and decreased apoptotic body formation by flow cytometry. These results indicated that the 5-10 kDa fraction of the Celluclast and Neutrase extracts from S. coreanum exhibited strong antioxidant activity over $H_2O_2$-mediated cell damage in vitro.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.33-38
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• 2009

Recently most of A/V devices are being adopted hi-tech of A VRCP and changed to mobile environment. AVRCP is designed to provide a standard interface to control A/V devices, hi-fi equipment, or others to allow a single remote control or other device to control all the A/V equipment to which a user has access. It may be used in concert with A2DP or VDP. The AVRCP defines two roles, that of a controller and target device. In AVRCP, the controller translates the detected user action to the A/V control signal, and then transmits it to a remote Bluetooth enabled device. It can be small and mixed mobile devices using bluetooth technologies. The functions available for a conventional infrared remote controller can be realized in this protocol. The remote control described in this protocol is designed specifically for A/V control only. We designed new DSP using Adaptive Acoustic Echo Canceller for bluetooth hands free based this AVRCP standard specifications.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.4
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• pp.486-505
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• 2011

The Korean miracle of economic growth or development has been quite well known across the world up to now, while being subject to theorization of its model. Compared with this, however, it is quite surprising to see how little about the spatial aspect of Korean development has been exposed in the field of development studies. In fact, for Korea, competent regional policy has turned out to be an important success factor for the spatial upgrading of a low-tech growth regime into a hi-tech one. This paper dissects Korea's regional policy experiences in three aspects from which it draws up a three-tier lesson. The first aspect is the conventional (overall) regional spatial upgrading policy of a developmental regime put in place since the 1960s onwards. The second is the new regional policy tailored to the regionalization of technological and industrial diffusion for new knowledge-based economy. The third is the prospective regional policy for the future advancement of the Korean economy.

• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.400-413
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• 2012

The purpose of this study was to look into the formation process and characteristics of local high-tech industrial complex with an example of the Ochang Scientific Industrial Complex and analyzed the characteristics by business type and size, transfer process of the companies in the Complex. For this purpose, statistical data of the companies were analyzed and a survey of them was conducted, and the following results were obtained. First, the Ochang Scientific Industrial Complex was created for agglomeration of IT industries in early days but now there are IT industries and BT industries mixed due to internal and external economic condition. Second, there are more small and medium companies than large companies in the Ochang Scientific Industrial Complex. These companies are in the stage of developing new products and marketing, and many of them were parts and materials developers of core technology or high innovation with venture identification. Third, high rates of the companies in the Ochang Scientific Industrial Complex came from the capital area and the Chungcheong area and the companies which moved in the Complex with their head quarters accounted for more than 70 percent. Fourth, the companies were classified into 5 types according to the type of product and the level of technical innovation.