• Biomedical Science Letters
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• v.4 no.2
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• pp.77-86
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• 1998

Age-related changes in the lens capsule and epithelium of cataractous patients, ranging from 20 to 7o years old, were studied by means or LM, immunohistochemistry, and TEM. The lens capsule was divided into four zones; the anterior, subanterior, middle, and basal zone. The van Gieson staining reaction for collagen was prominent at the anterior and subanterior parts of the lens capsule. The reaction was more decreased in the elder group than the younger group. The collagen type IV reaction was prominent at the anterior zone of the lens capsule and around the cell. The reaction was more decreased in the elder group than the younger group. 3. The Periodic Acid Shiff-Alcian Blue reaction for mucopolysaccharide was prominent at the anterior zone of the lens capsule. The reaction was more decreased in the elder group than the younger group. The Apoptotic reaction was prominent at the nucleus of the lens epithelial cell. In the elder the cataractous group, the number of the apoptotic cells was more decreased. The electron microscopic change of lens epithelial cells were characterized by the increase of lateral fold and the cytoplasm with various vacuoles and Golgi complex. In the basal part, lens epithelial cell protruded toward the lens capsule in the 20-year-old group. The basal part of the 40-year-old group was flattened and covered with the cytoplasmic processes of adjacent cells. In the 60-year-old group, the mass of rough filaments separated lens capsule and the basal part of the lens epithelial cell. The electron microscopic change of the middle part of lens capsule was characterized by the aggregation of electron dense materials in the 40-year-old group, and the appearance of filamentous materials and the decrease of electron dense granules in the 60-year-old group.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1273-1279
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• 2016

The objectives of this study were to determine an optimal cultivation time for populations of yeast and lactic acid bacteria (LAB) co-cultured in fermented milk and effects of soybean meal fermented milk (SBMFM) supplementation on rumen degradability in beef cattle using nylon bag technique. The study on an optimal cultivation time for yeast and LAB growth in fermented milk was determined at 0, 4, 8, 24, 48, 72, and 96 h post-cultivation. After fermenting for 4 days, an optimal cultivation time of yeast and LAB in fermented milk was selected and used for making the SBMFM product to study nylon bag technique. Two ruminal fistulated beef cattle ($410{\pm}10kg$) were used to study on the effect of SBMFM supplementation (0%, 3%, and 5% of total concentrate substrate) on rumen degradability using in situ method at incubation times of 0, 2, 4, 6, 12, 24, 48, and 72 h according to a Completely randomized design. The results revealed that the highest yeast and LAB population culture in fermented milk was found at 72 h-post cultivation. From in situ study, the soluble fractions at time zero (a), potential degradability (a+b) and effective degradability of dry matter (EDDM) linearly (p<0.01) increased with the increasing supplemental levels and the highest was in the 5% SBMFM supplemented group. However, there was no effect of SBMFM supplement on insoluble degradability fractions (b) and rate of degradation (c). In conclusion, the optimal fermented time for fermented milk with yeast and LAB was at 72 h-post cultivation and supplementation of SBMFM at 5% of total concentrate substrate could improve rumen degradability of beef cattle. However, further research on effect of SBMFM on rumen ecology and production performance in meat and milk should be conducted using in vivo both digestion and feeding trials.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.337-345
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• 1996

This study was conducted to investigate the protox activity, the PPIX accumulation and the activity of antioxidative enzymes of the oxyfluorfen-tolerant and -susceptible rice cultivars by oxyfluorfen and oxytluorfen-similar herbicides treatment. When treated with acifluorfen, bifenox or oxadiazon, the oxyfluorfen-tolerant rice cultivars showed less decreased in fresh weight than the susceptible rice cultivars. The inhibition of protox activity was in the order of acifluorfen > oxyfluorfen > bifenox > oxadiazon, and the PPIX accumulation was in the sequence of oxadiazon > acifluorfen > oxyfluorfen > bifenox. The inhibition of protox activity and the PPIX accumulation by the herbicide was greater in the susceptible rice cultivars than in the tolerant rice cultivars. The effect inhibiting the decrease of chlorophyll content resulting from the treatment of GC, tetrapyrrole biosynthesis inhibitor, was in the order of oxyfluorfen > acifluorfen > bifenox > oxadiazon, and the tolerant rice cultivar had more than the susceptible rice cultivar. In the treatment of DPE and oxadiazon, the activities of MDAR, POX and GR was higher in the tolerant rice cultivar than in the susceptible rice cultivar, and in the case of POX isozyme the activities of main D and E bands increased in the tolerant rice cultivars at tested herbicides but they didn't in the susceptible rice cultivar.

• Journal of the Economic Geographical Society of Korea
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• v.3 no.2
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• pp.43-61
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• 2000

This study investigate the spatial characteristics and corporate networks of foreign business service firms in Korea. Specifically intrafirm and extrafirm organization of foreign firms are addressed utilizing the corporate network perspective. For this purpose, this study conducted questionnaire and interview surveys for the foreign firms. Parent-subsidiary relationships are focused on the mechanisms by which Transnational Corporations (TNCs) headquarters control and coordinate their foreign affiliates and subsidiaries in order to achieve investment purpose in Korea (overseas market expansion). But extrafirm networks of foreign business services firms in Korea do not appear to play an important role in regional development to date. A low proportion of foreign firms is engaged in academics-industry linkages, and a low number o( foreign firms is formally linked with government organizations, research institutes, and trade associations. To conclude, Foreign direct investment firms in business services in Korea are characteristics by globalized intrafirm networks and localized interfirm and extrafirm networks. It is understood that regional development can be vitalized when Korean local firms have close relationships with technologically advanced foreign firms in tacit knowledge capacity. Foreign firms are able to play an important role in the development of business services in Korea. This study suggests that regional foreign direct investment policy should be targeted towards the corporate networking with foreign firms and domestic firms and incrementation of the potential of foreign firms as a knowledge-intensive industry.

• Journal of Environmental Health Sciences
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• v.36 no.5
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• pp.351-359
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• 2010

The objectives of this study were to understand the characteristics of residents in industrial areas and factors affecting exposure to the Volatile Organic Compounds(VOCs : Benzene, Toluene, Xylene) as well as to assess exposure levels according to house-type, and whether residents were indoors or outdoors. This research was designed to assess the differences in exposure levels to indoor, outdoor and personal VOCs in a case group and a control group across all areas, as well as in each different area, from May to October 2007, in. 110 residents of the G, Y and H industrial areas of the Jun-nam province. The geometric mea-levels of airborne benzene for the case group 1.31part per billion(ppb) indoor, 1.29 ppb outdoor, and 1.32 ppb for personal exposure were significantly higher than for the control group 0.99, 0.87 and 0.57 ppb, respectively. The geometric mean level for toluene personal exposure across the G, Y and H areas was 5.70 ppb for the case group and 6.31 ppb for the control group. While the outdoor level was 4.27 ppb for the case group and 5.06 ppb for the control group, The indoor level for the case group was 4.78 ppb, similar to that of the control group 4.69 ppb. The geometric mean levels for airborne xylene across the G, Y and H areas were 0.16 ppb(outdoor), 0.12 ppb(personal exposure) and 0.10 ppb(indoor) for the case group, and for the control group were 0.17(personal exposure) and 0.09 ppb(indoor and outdoor). The indoor/outdoor(I/O) ratio for case group is 1.19, while that of the control group is 1.15, indicating that the indoor level was higher than the outdoor level. The interrelationship differences among the three different types of levels in the air in the G, Y and H areas are statistically significant, except for the difference between the indoor and outdoor figures for xylene. In terms of the different types of houses and energy type uesd, the geometric mean level for airborne benzene, toluene and xylene for houses were 1.61, 5.39 and 0.12 ppb, respectively. while the figures for flats were 0.67, 3.32 and 0.05 ppb, respectively. Outdoors, the levels of benzene and toluene in flats were 0.71 and 2.62 ppb, respectively. and 1.58 and 5.35 ppb in houses. For personal exposure, the house levels of benzene, toluene and xylene were all higher than for flats. Houses using oil for heating have significantly higher levels than flats, which use gas for heating.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.29-34
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• 1987

The number of regrown shoots per plant for 2 weeks after mowing sharply increased in response to late mowing until June 6, and then the increments were slow. The number of regrown shoots for July 30 were many with early mowing until May 14, and then the numbers were rapidly decreased. The plant height regrown for 2 weeks after mowing was increased until May 14, and then decreased. The plant height regrown for July 30 was not sensitive to mowing time and the development was linearly shown. The fresh weight regrown for July 30 was only increased by late mowing. The regrowth rate of shoots for 2 weeks after mowing was much higher than untreated control and the ratio was decreased with late mowing and the ratio to untreated for control for July 30 was decreased up to 50% by late mowing. The regrowth rate of plant height for 2 weeks after mowing was rapidly decreased, but slowly decreased for July 30 mowing. The regrowth rate of fresh weight was higher until May 22, and then rapidly decreased by late mowing. The decreasing tendency for 2 weeks after mowing was more prominent them for July 30. The annual regrowth rates in shoots and plant height were slowly decreased, but the decreasing rate in fresh weight was rapidly done until May 15, and then decrement became up to 30% by late mowing.

• Journal of Embryo Transfer
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• v.19 no.2
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• pp.101-112
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• 2004

Chloride($Cl^-$) channels play critical roles in cell homeostasis and its specific functions such as volume regulation, differentiation, secretion, and membrane stabilization. The presence of these channels have been reported in all kinds of cells and even in frog oocytes. These essential role of $Cl^-$­ channels in cell homeostasis possibly play any role in egg homeostasis and in the early stage of development, however, there has been no report about the presence of $Cl^-$­ channel in the mammalian oocyte. This study was performed to elucidate the presence of $Cl^-$­ channels in hamster eggs. When allowing only $Cl^-$­ to pass through the channel of the egg membrane by using impermeant cation such as N-methyl-D-glucamine(NMDG), single channel currents were recorded. These channel currents showed typical long-lasted openings interrupted by rapid flickering. Mean open $time({\tau}o)$ was 43${\pm}$10.14 ms(n=9, at 50 mV). The open probability(Po) was decrease with depolarization. The current-voltage relation showed outward rectification. Outward slop conductance(32${\pm}$5.4 pS, n=22) was steeper than the inward slop conductance(10${\pm}$1.3 pS). Under the condition of symmetrical 140 mM NaCl, single channel currents were reversed at 0 mV(n=4). This reversal potential(Erev) was shifted from 0 mV at 140 mM concentration of internal NaCl(140 mM [Na+]i) to ­9.8${\pm}$0.5 mV(n=4) at 70 mM [Na+]i and 11.5${\pm}$1.9 mV at 280 mM [Na+]i(n=4) respectively, strongly suggesting that these are single $Cl^-$­ channel currents. To examine further whether this channel has pharmacological property of the $Cl^-$­ channel, specific Cl­ channel blockers, IAA-94(Indanyloxyacetic acid-94) and DIDS(4, 4'-diisothiocyan ostillben- 2-2'disulfonic acid) were applied. IAA-94 inhibited the channel current in a dose-dependent manner and revealed a rapid and flickering block. From these electrophysiological and pharmacological resluts, we found the novel $Cl^-$­ channel present in the hamster oocyte membrane. The first identification of $Cl^-$­ channel in the hamster oocyte may give a clue for the further study on the function of $Cl^-$­ channel in the fertilization and cell differentiation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.2
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• pp.61-65
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• 2009

In this paper, we report on the growth and optical characteristics of white-LED without fluorescent material. The growth of DH(double heterostructure) with AlGaN active layer was performed on a n-GaN/(0001) $Al_{2}O_{3}$ by the mixed-source HVPE and multi-sliding boat. The CRI(color rendering index) of packaging device charged in the range 72-93 with CIE chromaticity coordinates(x=$0.26{\sim}0.34$, y=$0.31{\sim}0.40$). And CCT(correlated color temperature) values was measured $5126{\sim}10406K$ with increasing injection current. The CIE point of conventional phosphor white LED shifts blue region, but cm point of non-phosphor white LED shifts opposite direction. These results show the mixed-source HVPE can be possible to newly fabricate method of phosphor free white LED with high CRI value.

• The Journal of Engineering Geology
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• v.11 no.1
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• pp.63-79
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• 2001

This study is aimed for estimating hydraulic parameters using the Cooper-Bredehoeft-Papadopulos, the Hvorslev, and the Bouwer & Rice methods at nineteen test holes in Me. Geumjeong area composed of Bulguksa granites, and for characterizing hydraulic properties at the test holes with relatioll to drill core data. The relation among hydraulic Dammeters obtained by the three methods is also considered. The study area is divided into four sub-areas to consider the hydraulic characteristics. The difference of hydraulic conductivity estimates between the injection and the withdrawal slug test may be due to penncable fracture distlibutions around the test hole and/or the disturbance of fine mateIials in the fractures induced by the pressure variation due to different mechanisms of test initiation. The hydraulic conductivity estimates detennined by the Cooper-Bredehoeft-Papadopulos, the Hvorslev and the Bouwer & Rice methods ranges from 10$^{-8}$ to lO$^{-5}$m/sec, and the ranges of average values are from 10$^{-7}$ to 10$^{-6}$m/sec. Also, the transmissivity ranges from 10$^{-7}$ to 10$^{-5}$$m^2$/sec. Comparing average hydraulic conductivity by the Cooper-Bredehoeft-Papadopulos, the Hvorslev and the Bouwer & Rice methods, by the Hvorslev method has the highest values, then the Bouwer & Rice method, and the Cooper-Bredehoeft-Papadopulos method has the lowest.

• The Korean Journal of Mycology
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• v.9 no.2
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• pp.93-97
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• 1981

The new strains of Mycogone perniciosa which could attack cream colored mushroom were collected and tested to find out their characteristics in comparison with the original strains. The optimum temperature for mycelial growth was $25^{\circ}C$, showing no difference between strains, but optimum pH was 6.0 for the original strains and pH 7.0 for the new ones. New strains did not survive at $50^{\circ}C$ for 60 minutes while original ones 40 minutes. Delan and Hamai were effective for controlling new strains and the mushroom strains which have scales showed resistance to the new strains of Mt. perniciosa regardless of the mushroom colors.