• Journal of Life Science
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• v.22 no.12
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• pp.1680-1687
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• 2012

Postmenopausal women are at an increased risk of developing coronary artery disease, primarily due to dyslipidemia that accompanies the loss of estrogen secretion. This study was performed to investigate the effects of Opuntia humifusa seed extracts on blood flow and serum lipid level in ovariectomized rats. Twenty-eight 9-week old female Sprague-Dawley rats were randomly assigned to four groups as sham-operated rats (SHAM), ovariectomized rats (OVX-CON), and ovariectomized rats that were treated with Opuntia humifusa seed extracts (OVX-OHS 2% and OVX-OHS 6%). The diets were fed to the rats for 7 weeks after operation. Serum total cholesterol and triglyceride contents decreased in the SHAM group compared to the OVX-CON group. Seven weeks of feeding of Opuntia humifusa seed extracts resulted in significant (p<0.05) lowering of serum triglyceride and a decreasing tendency in total cholesterol levels. The level of HDL-cholesterol in serum increased significantly by feeding diets containing the 2% and 6% Opuntia humifusa seed hot-water extract (p<0.05). Blood passage times were shorter in the Opuntia humifusa seed extract-supplemented groups than in the untreated group (OVX-CON). The platelet aggregation ability was lower in groups treated with Opuntia humifusa seed extracts than in the OVX-CON group. These results suggest that Opuntia humifusa seed extracts may have benefits in improving metabolic syndrome in menopausal women.

• Journal of Life Science
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• v.20 no.5
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• pp.775-781
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• 2010

The antioxidant activities of hot water extracts from fresh, red and black garlic processed in low temperatures were compared. The chromaticity value of browning garlic was between that of fresh and black garlic. Red garlic was similar in browning intensity to fresh garlic. Also, total phenol, flavonoids, total pyruvate and thiosulfate contents were similar between fresh and black garlic. DPPH, ABTs, NO radical scavenging activity and reducing power of red garlic were significantly higher than fresh garlic, but lower than those of black garlic. $\alpha$-Glucosidase inhibitory activity in red garlic was similar to that in black garlic. Antioxidant activities of red garlic were higher than fresh garlic but lower than black garlic, and it was confirmed that antioxidant activity by production of browning material through the thermal process was the main parameter of the biological activity in the aged red garlic.

• Journal of the Korean Society of Food Culture
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• v.9 no.4
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• pp.411-417
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• 1994

The extraction condition and quality attributes components in Oolong tea were investigated. Extraction yield was high in $80{\sim}85^{\circ}C$ above 50% ethanol solution. Sucrose content most high among the free sugar ranged $37.2{\sim}55.0\;mg/100\;g$, while arabinose was the least. Organic acids in ethanolic extracts were furmaric, citric and malic acid. Free amino acids were 15 kinds and contents of proline, tyrosine and glutamic acid were comparatively high. Tannin content extracted from water and 25% ethanol solution were 38.6 and $38.5\;{\mu}g/100\;g$, it decreased as ethanol concentration increase. Caffeine content did not changed as extraction conditions. Ascorbic acid content was $6.5\;{\mu}g/g$ when extracted from 25% ethanol solution, it decreased as ethanol concentration increase. Bitter and astringent taste affected to overall preference of Oolong tea. Tea manufactured from 25% ethanol solution extracts recorded most high organoleptic score than any other extraction condition.

• Journal of the Korean Society of Food Culture
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• v.19 no.1
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• pp.94-105
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• 2004

The biochemical components of Namcheondlggae, Miryangdlkkae 25, Boradlggae and Ipdlkkae 1 were measured. The samples were extracted with hot water, 60% acetone or 80% ethanol for screening physiological activity. The crude protein content (4.36%) was found in the Miryangdlkkae 25 and calcium content (497.5 mg%) was found in the Namcheondlggae among the tested 4 perilla loaves. Fructose was 30.86 mg% in the Namcheondlggae and free amino acids at all perilla leaves was detected seventeen. In Boradlggae, glutamic acid and alanine were 25.37 and 11.91 mg%. Totally nine non-volatile organic acids were also detected and the contents of malic acid and glutaric acid were 28.34 and 14.57 mg% in Boradlggae. The Miryangdlkkae 25 had the highest vitamin C amount which was 113.24 mg%. Angiotensin converting enzyme (ACE) inhibition activity of 60% acetone extract of Miryangdlkkae 25 was 39.20% when added as addition of 200 ppm level and xanthine oxidase inhibition activity of 80% ethanol extract of Boradlggae was 46.71%. Electron denoting activity of 60% acetone extract from Namcheohndlggae was the strongest inhibition activity as 98.19% when 200 ppm level of the sample extracts were added.

• Journal of the Korean Geotechnical Society
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• v.31 no.12
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• pp.17-27
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• 2015

In this study, we tried to precipitate calcium carbonate with carbonate ions decomposed from urea by plant extract and calcium ions dissolved in water. The clay particles carry a net negative charge on their surfaces. Such clay mineral was additionally mixed as a medium to improve soil strength and durability with environmentally-friendly way. The $1^{st}$ solution (plant extracts and urea) and the $2^{nd}$ solution (calcium chloride and clay) were mixed together with clean Nakdong River sand. Then, this mixed soil was compacted into a small cylindrical specimen and then air cured for 7 days in laboratory. The molar concentration of urea and calcium chloride was tested for three different conditions, 1, 5, and 7 mol. Three different clay contents (0, 1, and 3% per total weight) were mixed with sand. For each specimen, a series of unconfined compression test, a durability test, SEM, EDX and XRD analyses were carried out to evaluate its cementation and structure. As the molar concentration of the solution and clay content increased, the unconfined compressive strength and durability increased. The results of SEM, EDX and XRD analyses showed that calcite was precipitated around clay mineral. The thermogravimetry analysis indicated that calcium carbonate precipitated about 1~2% per total weight of the sample.

• Journal of the Korean Geotechnical Society
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• v.33 no.7
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• pp.55-64
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• 2017

A geological repository has been considered one of the most adequate options for the disposal of high-level radioactive waste. A geological repository will be constructed in a host rock at a depth of 500~1,000 meters below the ground surface. The geological repository system consists of a disposal canister with packed spent fuel, buffer material, backfill material, and intact rock. The buffer is very important to assure the disposal safety of high-level radioactive waste. It can restrain the release of radionuclide and protect the canister from the inflow of groundwater. High temperature in a disposal canister is released into the surrounding buffer material, and thus the thermal transfer behavior of the buffer material is very important to analyze the entire disposal safety. Therefore, this paper presents a thermal conductivity prediction model for the Kyungju compacted bentonite buffer material which is the only bentonite produced in Korea. Thermal conductivity of Kyungju bentonite was measured using a hot wire method according to various water contents and dry densities. With 39 data obtained by the hot wire method, a regression model to predict the thermal conductivity of Kyungju bentonite was suggested.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.621-628
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• 2005

Recently, it is noticed that autogenous shrinkage of high-performance concrete causes early crack in high performance concrete structures. The purpose of the present study is to derive a realistic equation to estimate the autogenous shrinkage of high performance concrete and to apply to structural analysis. For this purpose, several series of concrete specimens have been tested. When water-binder ratio is fixed to $30\%$, major test variables were the type and contents of mineral admixture. The autogenous shrinkage of HPC with fly ash slightly decreased than that of OPC concrete, but the use of blast furnace slag increased with the autogenous shrinkage. A prediction equation to estimate the autogenous shrinkage of HPC with mineral admixture was derived and proposed in this study. The proposed equation show reasonably good correlation with test data on autogenous shrinkage of HPC with mineral admixture. The finite element program developed in this study provides the useful tool for the flexural analysis including the autogenous shrinkage model. By this program, we know that the tensile stress considering the autogenous shrinkage of reinforced concrete structures increase $20\~27\%$ than that not considering.

• Journal of the Korean earth science society
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• v.27 no.3
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• pp.313-327
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• 2006

This study investigated the geochernical characteristics of Mn scale formed in groundwater wells at the Damyang area. The composition of Mn scale consists mainly of MnO and $SiO_2$. The content of Mn ranges from56.61wt.% to 68.69wt.%, and $SiO_2$ content ranges from 1.56wt.% to 10.45wt.%. The contents of Mo and Ba in Mn scale increased with increased depth; whereas, the content of Zn and Pb decreased with increased depth. Birnessite, quartz and feldspars were identified in Mn scales using x-ray powder diffraction studies. The IR absorption bands for Mn scales show major absorption band due to OH stretching, adsorbed molecular water, and birnessite stretching, respectively. In the SEM and EDS analysis, the Mn scale consists of botryoidal, spherical, spherulite, and empty straw structure. Those structure may be precipitated simply due to oversaturation with concentrated Mn content or may be formed through biogenic precipitation by Lepthothrix discophora. Under microanalysis using EDS on those structure surface of Mn scales, the Mn atomic percent range from 28 to 44, and such elements revealed the presence of Si, K, Na, Ca, Cl, Cu, Zn, and Ba.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.924-928
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• 2005

Toxin profiles of the paralytic shellfish poison (PSP) detected from domestic shellfishes collected at the market and imported. shellfishes were invested by fluorometric HPLC. Total 9 components in PSP were analysed from the imported ark shell, such as saxitoxin (STX), decarbamoylsaxitoxin (dcSTX), gonyautoxin (GTX) - 1,2,3,4,5, Cl and C2. Among those toxins, 7 components except for GTX1,4 were detected from domestic shellfishes and showed different toxin contents and toxin compositions by species. Only C group toxin (Cl +2) contained in short necked clam and hard clam $(0.06\~0.56\;nmole/g)$ which living under soil but, in the blue mussels and oysters which cultured in the open sea water, showed more higher toxicity and complicate toxin compositions. Toxin compositions in bloody clam and purplish washington clam were very different in some samples even in same species. GTX4 and GTX5 were higher in imported scallop and STX was higher in imported ark shell than other species.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.33-39
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• 2017

This study was carried out in order to closely examine the growth and the physiological response by shading levels of a container seedling of Daphniphyllum macropodum which is known as the species of having shade tolerance in a warm temperature evergreen broad-leaved tree. The shading treatment was regulated with the shading level of full sunlight, and 35%, 55%, 75% of full sunlight. As a result of surveying the height and the root collar diameter growth by the shading level, the height was the highest with 13.2 cm under 35% of shading. The root collar diameter was the highest with 4.99 mm under full sunlight. The organ-based (leaves, shoot and root) dry mass production and the whole dry mass production were higher with 1.38 g, 0.47 g, 0.87 g, 2.72 g, respectively, in order of 35% shading. As for chlorophyll a, b, and the total chlorophyll content, the highest chlorophyll content was shown under 75% of shading with the relatively highest shading level. The ratio of chlorophyll a to chlorophyll b (a/b) was the highest under 35% of shading. The photosynthetic rate, stomatal conductance and water use efficiency were the highest with $12.3{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$, $0.27molH_2O{\cdot}m^{-2}{\cdot}s^{-1}$, $3.53{\mu}molCO_2{\cdot}mmol^{-1}H_2O$, respectively, under 35% of shading. As a result of surveying the whole experiment, D. macropodum grows nicely by maintaining 35% shading.