• Journal of the Korean Society for Precision Engineering
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• v.25 no.1
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• pp.145-150
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• 2008

One of the unresolved questions in articular cartilage biomechanics is the magnitude of the dynamic modulus and tissue compressive strains under physiological loading conditions. The objective of this study was to characterize the dynamic modulus and compressive strain magnitudes of bovine articular cartilage at physiological compressive stress level and loading frequency. Four bovine calf shoulder joints (ages 2-4 months) were loaded in Instron testing system under load control, with a load amplitude up to 800 N and loading frequency of 1 Hz, resulting in peak engineering stress amplitude of ${\sim}5.8\;MPa$. The corresponding peak deformation of the articular layer reached ${\sim}27%$ of its thickness. The effective dynamic modulus determined from the slope of stress versus strain curve was ${\sim}23\;MPa$, and the phase angle difference between the applied stress and measured strain which is equivalent to the area of the hystresis loop in the stress-strain response was ${\sim}8.3^{\circ}$. These results are representative of the functional properties of articular cartilage in a physiological loading environment. This study provides novel experimental findings on the physiological strain magnitudes and dynamic modulus achieved in intact articular layers under cyclical loading conditions.

• Korean Journal of Medicinal Crop Science
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• v.13 no.5
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• pp.242-248
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• 2005

The present study was designed to elucidate the physiological changes with age by chronic administration of red ginseng. All rats were reared in the conventional system. Ginseng treated rats were continously supplied with ginseng water extracts together water from 6 weeks of age to the age 24 months. Rats did not show any discernible signs or the rejection symptoms by red ginseng water extracts. A long-term administration of red ginseng extracts did not cause any physiological changes in the gain of body and organs weight, food intake and general properties of urine. However, red ginseng caused to decrease the level of serum cholesterol, glucose and TBARS, and it attenuated effectively the age-dependent decline of LDH activity. Other biochemical parameters measured from blood and general properties of urine were not significantly changed. These results suggest that long-term administration of red ginseng to rat does not cause any clear physiological changes in appearance and urine, and it retards age-related deteriorations in some biochemical parameters such as LDL-cholesterol, glucose and LDH in serum.

• Korean Journal of Plant Resources
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• v.28 no.4
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• pp.533-540
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• 2015

Germination properties, leachate electrical conductivity (EC), and inorganic compound leaching were analyzed to ascertain the storage ability and change of physiological characteristics during storage of Hippophae rhamnoides seeds. Seeds were placed in an incubator at 25℃ and sown in different soil media (sand, vermiculite and horticultural substrate) after being stored for 6, 18 and 30 months at 2℃. All germination properties decreased in accordance to an increase of the seed storage period. Compared with the seed storage for 18 months, germination percentage (GP), germination performance index (GPI), and germination value (GV) of seeds stored for 30 months decreased by more than 50%. When the seeds were sown in different soil media in a greenhouse, those germination properties were similar to the seeds germinated in an incubator, and mean germination time, GPI and GV had a significant difference except GP among soil media. EC and inorganic ion concentration had a strong positive correlation with the seed storage period, but the ratios of inorganic ions from stored seeds revealed that K⁺/Mg²⁺ and Na⁺/Mg²⁺ were inversely correlated with the storage period.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.spc1
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• pp.10-24
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• 1996

[ ($1{\to}3$) ], ($1{\to}4$)-${\beta}$-D-glucans(${\beta}-glucans$) are a major component of the cell walls of grasses as a component of the cereal endosperm and aleurone cell walls. Although ${\beta}-glucans$ exist in all cereals, their concentration is highest in oats and barley. Genetic and environmental differences are found in total ${\beta}-glucan$ content. Both oats and barley ${\beta}-glucans$ have cholesterol-lowering effects. This suggests possible use as food additives. Structural characterization of ${\beta}-glucan$ is important because structure can influence physical and physiological properties. In this review, ${\beta}-glucans$ of barley and oats are discussed in details including structure, chemical and physical properties, and nutritional implications. The use of barley and oat products as well as ${\beta}-glucan$ as a food additive continues to increase. This can provide an additional market for barley and oats, thus increasing the value of the crops.

• Food Science and Preservation
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• v.5 no.2
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• pp.191-197
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• 1998

Garlic is an important condimental vegetable which has many minerals and numerous organic sulfur compounds. Owing to these components, garlic has many medicinal properties and physiological activities on human health. It can lower sect lipid levels and reduce the severity of cholesterol-induced atherosclerosis. And it appeals to protect against mutagenic and carcinogenic effects. Today's our eating habit is concentrated on the physiological function in floods rather than their taste or mutagenic. To improve garlic's value as a flood or a vegetable, further scientific researches about its volatile and nonvolatile sulfur compounds through the biochemical approach are needed. In addition to that, both areas that the development of garlic-processed goods and utilization of garlic as materials for medicine must be actively studied.

• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.273-277
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• 2002

Physiological properties of root and stolen of Gamcho (Licorice, Glycyrrhiza uralensis Fischer) were compared following irradiation at 20 kGy. The root and stolen of Gamcho were extracted with 70 % ethanol, irradiated and stoved in a 4"C refrigerator. Irradiation induced color changes, electron donating ability (EDA), and tyro-sinase inhibition effect (TIE) were investigated. The color of the non-irradiated stolen extract was darker than the non-irradiated root extract (p<0.05), but irradiation eliminated color differences between stolen and root extracts. Generally, irradiation did not affect EDA and TIE of either of the extracts. However, EDA and TIE were higher in stolen extract than in root extract, when the higher dilution factor was considered. These results indicate that the stolen of Gamcho, which is mostly wasted, is a valuable source of phytochemicals with greater EDA and TIE activities than Gamcho root.root.

• Textile Coloration and Finishing
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• v.20 no.6
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• pp.69-74
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• 2008

In this paper, a comfort evaluation system based on a product-focused process design (PFPD) has been proposed for high comforts interior seat covers. Correlations between comforts properties and physical/thermal properties of interior seat covers were examined by combining traditional regression analysis and data mining techniques. A skin sensorial comfort of leather samples was evaluated by only human tactile sensation. The adjectives of leather car seat covers are 'Soft', 'Sticky' and 'Elastic'. Thermo-physiological comfort properties of leather samples were evaluated by only human tactile sensation. The adjectives of leather car seat covers are 'Coolness to the touch' and 'Thermal and humid'. Skin sensorial comforts of cloth samples were evaluated by only human tactile sensation. The adjectives of cloth car seat covers are 'Soft', 'Smooth', 'Voluminous' and 'Elastic'. Thermo-physiological comforts of cloth samples were evaluated by only human tactile sensation. The adjectives of cloth car seat covers are 'Coolness to the touch' and 'Thermal and humid'.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.2
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• pp.53-61
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• 2013

The present study elucidated the growth properties of Sasa borealis communities distributed in the lower layer of deciduous broadleaf forests in temperate zones and analyzed the correlation between the growth properties of S. borealis and positional environmental factors. The higher the culm height of S. borealis was, the higher the values of the leaf number, leaf area, and foliage layer thickness became. This might be because as the culm height of S. borealis increased, the acquisition of light sources became easier so that the biomass of leaves increased simultaneously for smooth anabolism. S. borealis seem to change their growth mode for smooth acquisition of light resources. The culm density of S. borealis and the leaf number, leaf area and foliage layer thickness of S. borealis did not show any clear correlation. The values of the culm height, leaf number, leaf area, and foliage layer thickness of S. borealis as the above altitude of the location of S. borealis increased. It seems like that growth conditions such as temperatures and winds are deteriorated as the above altitude of the location of S. borealis increased so that S. borealis becomes smaller. No clear correlations were shown between the physiochemical properties of soil and S. borealis' growth properties. It seems like that the growth of S. borealis complexly intertwined with diverse environmental factors and that due to the physiological integration of S. borealis, certain physiochemical properties do not unilaterally affect S. borealis' growth properties.

• Journal of Mechanical Science and Technology
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• v.17 no.2
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• pp.296-309
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• 2003

The periodicity of the physiological flow has been the major interest of analytic research in this field up to now Among the mechanical forces stimulating the biochemical reaction of endothelial cells on the wall, the wall shear stresses show the strongest effect to the biochemical product. The objective of present study is to find the effects of velocity waveform on the wall shear stresses and pressure distribution along the artery and to present some correlation of the velocity waveform with the clinical observations. In order to investigate the complex flow phenomena in the bifurcated tube, constitutive equations, which are suitable to describe the rheological properties of the non-Newtonian fluids, are determined, and pulsatile momemtum equations are solved by the finite volume prediction. The results show that pressure and wall shear stresses are related to the velocity waveform of the physiological flow and the blood viscosity. And the variational tendency of the wall shear stresses along the flow direction is very similar to the applied sinusoidal and physiological velocity waveforms, but the stress values are quite different depending on the local region. Under the sinusoidal velocity waveform, a Newtonian fluid and blood show big differences in velocity. pressure, and wall shear stress as a function of time, but the differences under the physiological velocity waveform are negligibly small.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.266-274
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• 2001

The chemical properties and physiological activities of the freeze-dried stromata of Cordyceps militaris were examined. A proximate analysis exhibited that the stromata consisted mainly of crude carbohydrate (74.3%), crude protein (11.5%), and moisture content (8.7%), with a low content of crude ash (4.%) and fat (1.3%). The carbohydrate was mostly composed of glucose (88.6%). A large quantity of essential fatty acids, including linolenic acid (33.8%) was also observed. An analysis of the component amino acid showed a relatively high ratio of the essential amino acids, lysine (101.2 mg/g), methionine (62.7 mg/g), and acidic amino acids of glutamic aicd (57.5 mg/g) and aspartic acid (43.9 mg/g), whereas a low of tyrosine content (4.7 mg/g). An examination of the cordycepin content indicated tht the stromata and mycelium-embedded media (silkworm pupae) contained 0.2% and 0.5%, respectively. From the examination of the physiological activities, based on methanol extract (M), ethylacetate extract (EA), and hot-water extract (HW) fractions of the stromata, the hot-water extract (HW) fraction showed the most potent intestinal immune modulating activity, anticoagulant activity, and anticomplementary activity, whereas the ethylacetate extract (EA) fraction exhihited a radical scavenging activity. Therefore, the results from the present study indicate that the stromata of C. militaris contain various healthy chemical ingredients, and that especially boiled water extract of whole body would apprear to provide beneficial physiological activities.