• Journal of Nutrition and Health
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• v.28 no.8
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• pp.727-736
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• 1995

The hypoglycemic effect of Polygonatum odoratum var. Pluriflorum Ohwi was investigated after extracted with methanol. The methanol extract was fractionated into 4 layers ; hexane, chloroform, butanol and aqueous. Fifty male Sprague-Dawley rats(200-300g) were induced diabetes mellitus by the streptozotocin injection(45mg/kg B.W) into the tail vein and were divided into 5 groups ; diabetic control and 4 experimental groups. All groups of the rats were fed on a AIN-76 diet, and the 4 experimental groups were orally administered with each fraction(500mg/kg B.W) for 12 days and the diabetic control group was orally administered CMC. The body weight gain was monitered and the blood levels of glucose and cholesterol were measured. Levels of protein, triglyceride, and free fatty acid in plasma were analysed. The contents of protein, triglyceride and glycogen in liver and of protein and glycogen in muscle were also determined. The body weight gain was shown significantly higher in the H2O fraction group than that in the diabetic control group and the heart weight was greater in the CHCl3 group. The extents of blood glucose decrement were greater in the BuOH and H2O groups than that in the control group. The urinary glucose excretion was shown relatively small amount in the BuOH and H2O groups. The plasma cholesterol and protein levels were not influenced by these four fractions in diabetic rats. The liver glycogen level was significantly higher in the BuOH group. The results suggest that the orally administered BuOH and H2O fraction of Polygonatum odoratum var. Pluriflorum Ohwi exhibited hypoglycemic effect in streptozotocin induced diabetic rats.

• Composites Research
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• v.33 no.1
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• pp.1-6
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• 2020

Dispersion and electrical resistance (ER) properties of polyurethane (PU) type topcoat were evaluated using carbon nanotube (CNT) with different CNT weight fraction. CNT was dispersed in PU type topcoat using ultra sonication dispersion method. CNT/PU topcoat was coated on carbon fiber reinforced epoxy composite (CFRC) surface using gravity feed spraying method. Static contact angles of CFRC and CNT/PU topcoat were performed using 4 types of solvents to calculate the work of adhesion between CNT/PU topcoat and CFRC surface. Surface resistance of CNT added PU topcoat was measured to determine CNT dispersion. Adhesion property between CNT/PU topcoat and CFRC was determined via cross hatch cutting test based on ASTM D3359. The optimized condition of CNT weight fraction was found.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.1
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• pp.37-44
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• 1995

Concentration of particulate nitrate classified by formation mechanism and particle diameter in ambient air was determined from Feb. to Oct. 1993. Sampling was carried out using a two-stage Andersen air sampler at the top of a five-story building located at Kon-Kuk University in seoul. Concentration of N $H_{4}$N $O_{3}$ in TSP was measured by pyrolysis of sample filters at 160.deg.C for 1hr. concentration of N $H_{4}$N $O_{3}$ was higher in winter time compared with that in summmer time. Also, concentration of N $H_{4}$N $O_{3}$ was higher in fine particles compared with that in coarse particle. The range of N $H_{4}$N $O_{3}$ concentration was between 2.9 and 9.9.mu.g/ $m^{3}$. Weight fraction of N $H_{4}$N $O_{3}$ in total particulate nitrate was 31.1 .sim. 59.5%, and weight fraction of N $H_{4}$N $O_{3}$ in TSP was 2.1 .sim. 11.2%. Concentration of NaN $O_{3}$, which originated from sea salt, was highest in spring time and lowest in summer time,and the concentration range was between 0.1 and 0.7.mu.g/ $m^{3}$. NaN $O_{3}$/TSP ratio was very low (0.1 .sim. 0.4%) indicating that the portion of NaN $O_{3}$in TSP was negligible. Concentration of particulate nitrate originated from soil was 2.4 .sim. 2.9.mu.g/ $m^{3}$. Weight fraction of that in total particulate nitrate was 14.0 .sim. 37.1%.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.49-59
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• 1986

To examine safety of Ganoderma lucidum, it was extracted with hot water (Fraction A). After the extract was dialyzed and freeze-dried, a polysaccharide fraction (Fraction B) was obtained and examined for acute and subacute toxicity. In the acute toxicity tests of Fr. A and Fr. B on mice, both agents did not show any serious and lethal effects. The results showed that 50% lethal doses were higher than 5,000 mg/kg. The experiments of oral administration of Fr. A (5,000 mg/kg) to mice for 30 days showed that there were no changes in body weight, hematological features and organ weight.

• Advances in nano research
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• v.14 no.4
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• pp.375-389
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• 2023

In this study, free vibration analysis of functionally graded (FG) porous truncated conical shell panels reinforced by graphene platelets (GPLs) has been investigated for the first time. Additionally, the effect of three different types of porosity distribution and five different types of GPLs patterns on dynamic response of the shell are also studied. Halpin-Tsai micromechanical model and Voigt's rule are used to determine Young modulus, shear modulus and Poisson's ratio with mass densities of the shell, respectively. The main novelties of present study are: applying 3D elasticity theory and the finite element method in conjunction with Rayleigh-Ritz method to give more accurate results unlike other simplified shell theories, and also presenting a general 3D solution in cylindrical coordinate system that can be used for analyses of different structures such as circular, annular and annular sector plates, cylindrical shells and panels, and conical shells and panels. A convergence study is performed to justify the correctness of the obtained solution and numerical results. The impact of porosity and GPLs patterns, the volume of voids, the weight fraction of graphene nanofillers, semi vertex and span angles of the cone, and various boundary conditions on natural frequencies of the functionally graded panel have been comprehensively studied and discussed. The results show that the most important parameter on dynamic response of FG porous truncated conical panel is the weight fraction of nanofiller and adding 1% weight fraction of nanofiller could increase 57% approximately the amounts of natural frequencies of the shell. Moreover, the porosity distribution has great effect on the value of natural frequency of structure rather than the porosity coefficient.

• Korean Journal of Animal Reproduction
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• v.21 no.2
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• pp.111-116
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• 1997

We determined the effects of follicular fluid fractions in the maturation medium on bovine oocyte maturation, fertilization and subsequent development, as well as on number of cells in blastocysts following culture. Follicular fluid and oocytes from bovine follicles less than 5 mm in diameter were collected from the ovaries of slaughtered cows. Follicular fluid was separated into different molecular weight fractions by untrafiltration through a membrane using a centrifuge at 500$\times$g, for 2h. For the maturation medium, follicular fluid fractions (30%, v/v), whole fluid (30%) or PVP(3mg/ml) were added to TCM 199(0.1$\mu\textrm{g}$/ml estradiol-17$\beta$, 100IU hCG). After maturation for 24h, oocytes were fertilized in vitro with bull frozen-thawed spermatozoa and cultured on a monolayer of granulosa cells for 9 days after fertilization. There were no differences in maturation rates or fertilization rates among any maturation conditions. The rates of development to >2-cell stage of the oocytes were significantly decreased when fraction of follicular fluid below 10,000 MW were added into maturation medium, compared with control and fraction above 10,000 MW(26.0% vs 40.8% to 64.0%, respectveily. p<0.01). Likewise, the rates of development to blastocysts of fertilized oocytes were significantly decreased in maturation medium containing fraction of follicular fluid (<10,000 MW). The average cell number of blastocysts derived from oocytes that matured in the fraction(>10,000 MW) of follicular fluid was 154.7$\pm$13.7. These embryos contained more cells than those matured in whole follicular fluid, or the fraction(<10, 000 MW) of follicular fluid or control(107.0$\pm$8.4, 91.8$\pm$11.8 and 95.8$\pm$6.2, respectively). In conclusion, we found that fractions of follicular fluid contained factors stimulating or inhibiting oocyte cytoplasmic matruation. These suggest that a factor(s) inducing cytoplasmic maturation of oocytes may exist in >10,000 MW fraction of follicular fluid.

• Journal of Nutrition and Health
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• v.31 no.9
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• pp.1385-1393
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• 1998

The hypoglycemic effects of butanol(BuOH) fraction of Polygonatum odoratum with vitamin E in streptozotocin(STZ)-induced diabetic rats were investigated. Sprague-Dawley rats weighing 200-230g were devided into five groups, and four groups induced diabetes mellitus by the STZ injection(45mg/kg b.w.) into the tail vein : Normal, diabetic-control, and three diabetic experimental groups(p. odoratum group, P. od-vit. E group and Vit. E group). All groups were fed on a AIN-76 diet, and the experimental groups were orally administered with the BuOH fraction of Polygonatum odoratum(500mg/kg b.w.) and vitamin E(10mg/kg b.w.) for 14 days. The body weight, diet intake and organ weights were monitored. The plasma levels of glucose, insulin, cholesterol, triglyceride, HDL-cholesterol and aspartate and alanine aminotransferase activities were analyzed. The levels of glycogen in liver and muscle, cholesterol in liver were determined. The malondialdehyde(MDA) levels in liver, kidney and lung were assayed. The body weight loss was seen in P. odoratum group, P. od-vit. E group, Vit. E group and diabetic control group, while the loss in P. odoratum group was much less than that in the diabetic control group. The plasma glucose levels were significantly lowered in P. odoratum group compared to diabetic control group. The plasma insulin levels were noticeably higher in P. odoratum and Vit. E groups. The rats in P. odoratum and P. od-vit. E group showed higher liver glycogen levels than in the diabetic control group. The MDA levels in liver, kidney and lung were also significantly reduced in P. od-vit. E and Vit. E groups compared to the diabetic control group. The results suggest that the administration of BuOH fraction of Polygonatum odoratum along with vitamin E reduced blood glucose levels and peroxidative tissue damage in STZ-induced diabetic rats, showing the possibility of preventive and therapeutic use of the wild edible plant to the diabetes mellitus. (Korean J Nutrition 31(9) : 1385-1393, 1998)

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.2
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• pp.32-40
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• 2017

In this study, the procedures for quantitative measurement of void contents of carbon fiber/epoxy composites were suggested. Two types of the composites were considered: autoclave cured composite and filament wound composite. Void contents of the composites were evaluated by the density of the composites and their constituents, which was determined from weights in the air and water, and the weight fraction and volume fraction of the constituents obtained from the digestion method and combustion method. The surfaces of filtered carbon fibers were examined by FE-SEM in order to investigate the validity of resin removal from the composites. According to the results, the resin in the composites could be fully removed by the digestion method and combustion method. Therefore, the weight fraction and volume fraction of the constituents, and void content of the composites could be quantitatively obtained by the suggested procedures.

• Natural Product Sciences
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• v.16 no.2
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• pp.80-87
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• 2010

High performance liquid chromatography (HPLC) analysis on the MeOH extract of Ligularia stenocephala leaves identified six caffeoylquinic acids, viz. 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoyl-mucoquinic acid, 3,5-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, and 3-Ocaffeoylquinic acid using standard compounds, and determined the quantity of each extract. Percentage of total caffeoylquinic acids of the MeOH extract and its BuOH fraction were calculated as $67.83{\pm}3.79%$ and $94.52{\pm}1.84%$, respectively. Since the caffeoylquinic acid-rich MeOH extract exhibited a potent peroxynitrite-scavenging effect in vitro ($IC_{50}=0.87{\pm}0.33\;{\mu}g/ml$ (mean $\pm$ SEM)), the experiment was designed to identify whether or not that extract has an anti-obesity effect on rat obesity induced by high fat diet. Oral administration of the MeOH extract and its BuOH fraction abundant in caffeoylquinic acid decreased the rat body weight to the level of untreated group and decreased abdominal fat pad weight. The atherogenic index and thiobarbituric acid-reactive substance (TBARS) values were restored by treatment, indicating that the caffeoylquinic acid-rich extract probably inhibited hyperlipidemia and oxidative stress caused by high fat diet. These results suggest that L. stenocephala in vegetable form or its caffeoylquinic acid-rich fraction (BuOH fraction) as an agent can be used for treatment or prevention of obesity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.652-665
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• 1997

Allelopathic effects on some crops(rice, barley, wheat, Chinese cabbage, leaf mustard, onion, welsh onion, tobacco, red pepper) for extracts of Phytolacca americana and Armoracia rusticana were investigated in MS solid medium. Germination percentage, radicle length, hypocotyl length, plant height, fresh weight, dry weight, and seedling vigor were rapidly inhibited by methanol extract from Phytolacca americana according to increase of the concentration in test plants. Autotoxicity of Phytolacca americana began to appear at concentrations greater than 50$\mu$l methanol extracts per 20ml medium. The fresh weight and dry weight of Phytolacca americana were also decreased by its own methanol extract according to increase of the concentration. Initial amounts of growth of all crops were also inhibited by methanol extracts from Armoracia rusticana, but the inhibitory effects were lowered than those of methanol extracts of Phytolacca americana. Of four fractions, ethyl acetate, petroleum ether, $1^{st}H_2O, 2^{nd}H_2O$, reextracted from methanol extracts of Phytolacca americana, the ethyl acetate fraction showed the highest allelopathic effects on germination percentage and initial amounts of growth. Chlorophyll contents of rice, barley and Chinese cabbage were more inhibited in the ethyl acetate fraction than in the other fractions. Free proline content of Chinese cabbage was increased 31.2 times in the 100$\mu l$ ethyl acetate fraction, and the contents of rice and barley were also increased according to concentration levels in the ethyl acetate fraction.