• The Korean Journal of Food And Nutrition
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• v.6 no.3
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• pp.219-230
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• 1993

This research aims to study the changes In gastrointestinal function attributed to aging In human. The thresholds for recognition and detection of flavors became elevated and salivary gland acinar cells decreased in the old age. But most esophageal function remained relatively Intact. Although gastric emptying time has been slowed with aging, the total intestinal transit time did not differ. Atropic gastritis due to H. pylori in old man decreased secretion of acid and Intrinsic factor and absorbability of calcium and iron. Pancreatic secretion is droned in older persons. Prevalence of gallstones rised with age. Liver size and portal blood flow decreased significantly with age. Mucosal surface area has been reported to be slightly diminished in the aging man. Glucose transporters decreased and Insulin tolerance Increased. Absorption of aromatic amino acid is diminished with age. Dietary protein In that aging human increased fecal nitrogen excretion. Vitamin A tolerance increased. Vitamin D receptor concentration decreased and resistance to 1,25-(OH)2D3 action increased. Permeability of aging small Intestine Increased. Zinc balance dirt not differ Copper absorption appeared not to be significantly affected by age. Neurotensin secretion decreased thus slowed colonic peristaltic movements and Intestinal mucosal growth.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.399-403
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• 1998

Absorption coefficient per mass unit of particles, specific absorption coefficient, is one of main parameters in developing algorithms for ocean color remote sensing. Specific absorption coefficient of chlorophyll (a$^*_{ph}$) and suspended sediment (SS) were analyzed by "wet filter technique" and "Kishino method" for data sets observed in the Yellow and Mediterranean Seas. A new data-recovering method for the filter technique was also developed using spectrum slopes. This method recovered the baseline of spectrum that was often missed in the Kishino method. High a$^*_{ph}$($\lambda$) values in the oligotrophic Mediterranean Sea and low values in the Yellow Sea were observed, spanning over the range of 0.02 to 0.12 $m^2$/mg, at the chlorophyll maximum absorption wavelength 440nm. The empirical relationship between a$^*_{ph}$ and chlorophyll concentration was found to fit a power function, which was slightly different from that proposed by Bricaud et ai. (1995). Absorption specific coefficients for suspended sediment (a$^*_{SS}$) didn't show any relationship with concentrations of suspended sediment. However, the average value of a$^*_{SS}$ at 440nm was close to the specific absorption coefficient of soil (loess) measured by Ahn (1990). The more-pronounced variability of a$^*_{SS}$ than a$^*_{ph}$ perhaps can explain more wide range of size-distribution for SS, which were determined by their specific gravity and agitation of water mass in the sea surface.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.270-275
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• 2012

This paper presents a portable and compact optical device which can conveniently be used to perform a functional analysis of human liver function. The proposed system employed red/green LEDs, as a light source, and CMOS image sensor, which is commonly used in cellular phones. With this system, several blood serum samples have been evaluated for liver functional analysis by measuring light absorption level through the blood serum samples depending on aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin concentration. The light absorption through the blood serum samples containing AST, ALT, or total bilirubin can provide their concentrations. The green light absorption is more sensitive to the concentration of AST or ALT, and the red light absorption is more sensitive to the total bilirubuin concentration. Additional calibration steps were performed by using a MATLAB program in order to eliminate the light scattering effects from the extraneous particles existing in each blood serum sample. From the blind test, three standard light intensity curves through each enzyme have been obtained and the enzyme concentration values have been compared to those obtained from a commercially available biochemistry analyzer (Toshiba 200 FR). The average percent difference in the obtained concentrations from two systems for AST, ALT, and total bilirubin concentration came out to be 7.79%, 7.98%. and 7.56%, respectively, with the adjusted coefficient of determination (R2) higher than 0.98. This system can possibly lead to a low-cost and simple system that can be used as a point-of-care (POC) system in a condition without advanced equipments.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.286-286
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• 1996

In order to elucidate the mechanism of action of transdermal absorption-enhancing compounds, i.e., pyrrolidone derivatives (2-pyrrolidone, 1-methyl-2-pyrrolidone, 1-ethyl-2-pyrrolidone, 1,5-dimethyl-pyrrolidone and 5-methyl-2-pyrrolidone), multilamellar liposome was prepared from the simulated stratum corneum lipid and employed as a model system for the barrier function of the stratum corneum. The liposomal membrane of the stratum corneum lipid liposome (SCLL) behaves as an osmometer and has an excellent barrier function. In addition, its phase transition temperatures are similar to those of human stratum corneum intercellular lipid region. Therefore, SCLL seems to be a useful skin model. To estimate the barrier function of SCLL, the osmotic behavior of SCLL was measured in the presence of pyrrolidone derivatives and the effect on the phase transition temperature of SCLL was also investigated using differential calorimetry. Above a certain concentration (MLAC), enhances perturb the barrier function of the liposome. The relationship between MLACs and the partition coefficient of the pyrrolidone derivatives was observed; the greater the partition coefficients, the smaller the MLAC. This suggests that the more hydrophobic enhancers penetrate into the lipid layer more easily and reduce the barrier function of membrane more effectively. The results of differential scanning thermograms of the SCLL suggest that the pyrrolidone derivatives had incorporated into the lipid layer in the liposome and increased the fluidity of the lipid layer in the liposome. Such activity might have some correlation with the transdermal absorption-enhancing activity these compounds.

• Journal of Pharmaceutical Investigation
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• v.7 no.1_4
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• pp.22-27
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• 1977

Absorption of sulfisoxazole after oral administration was significantly increased by small dose(60mg/kg) of alloxan but not increased significantly by large dose (160mg/kg) of alloxan from that of normal rabbits. Pretreatment with alloxan did not give any effect on clearance of sulfisoxazole. As the results, It could come to conclusion that in creased absorption of the sulfisoxazole administered small dose of the alloxan was influenced by transport of intestinal membrane or intestinal enzyme activation or increase of intestinal absorption function.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.11
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• pp.34-41
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• 2001

This study is to investigate the energy absorption characteristics of CFRP(Carbon-Fiber Reinforced Plastics) tubes on static and dynamic tests. Axial static compression tests have been carried out using the static testing machine(Shin-gang buckling testing machine) and dynamic compression tests have been utilized using an vertical crushing testing machine. When such tubes are subjected to crushing loads, the response is complex and depends on the interaction between the different mechanisms that could control the crushing process. The collapse characteristics and energy absorption have been examined for various tubes. Energy absorption of the tubes are increased as changes in the lay-up which may increase the modulus of tubes. The results have been varied significantly as a function of ply orientation and interlaminar number.

• Korean Journal of Optics and Photonics
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• v.4 no.3
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• pp.347-353
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• 1993

A picosecond transient absorption kinetic spectrometer using a pump-probe method is presented and compared with other methods of picosecond transient absorption measurements. This constructed kinetic spectrometer detects the transient transmittance of sample using a lock-in amplifier as a function of delay time between pump and probe pulses generated from a picosecond mode-locked cw dye laser. Typical transient absorption and ground state bleach recovery kinetic profiles measured with this spectrometer are shown. Excellent kinetic curves of transient absorption or ground state bleach recovery may be obtained at single wavelengths with this spectrometer.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.622-629
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• 2011

This study was performed to investigate the effect of rice bran dietary fiber powder on serum lipid levels, bowel function, and mineral absorption in rats. Four weeks old male Sprague Dawley rats(SD rat) were divided into four groups : control group fed 5% cellulose as a fiber source, RB10 fed 5% of cellulose and 10% of rice bran dietary fiber powder, RB20 and RB30. The animals were fed the experimental diets for 4 weeks. Serum lipid levels were not significantly different among the groups. But, fecal total cholesterol(TC), triglycerides(TG), and high density lipoprotein cholesterol(HDL-c) excretion increased in the RB30 group. Fecal weight and fecal water content were higher in the rice bran added groups than those in the control group. Transit time was significantly shorter in the rice bran fiber-added groups than that in the control. Weight of the stomach and large intestine in the RB20 and RB30 groups were significantly greater than those in the other groups. Absorption rates of Ca, Mg, P, and Zn decreased significantly in the RB30 group compared to those in the other groups. A high amount of rice bran increased fecal lipids, including TC, TG and HDL-c. Rice bran increased fecal weight and fecal water content and shortened gastrointestinal transit time. However, a high level of rice bran diet decreased mineral absorption rates.

• Journal of the Korean Wood Science and Technology
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• v.40 no.1
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• pp.38-43
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• 2012

Sound absorption capability and mechanical properties such as MOE and MOR in bending of miscanthus particle based board were estimated by the two microphone transfer function method and three point bending method, respectively. The results are summarized as follows: The sound absorption coefficients of miscanthus particle based board was higher than those of commercial gypsum board which is well used as sound absorbing barrier. The MOR and MOE of miscanthus particle based board increased with increasing of board density. The sound absorption coefficients of miscanthus particle based board were 50~80% in the frequency range of about 1~2.5 Khz. In entire frequency range, those value increased with target board density decreasing.

• Journal of the Korean Wood Science and Technology
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• v.47 no.3
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• pp.290-298
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• 2019

The sound absorption coefficient and transmission loss of several types of rice hull mats with varying apparent densities and thicknesses are estimated in this paper using the transfer function and matrix methods, respectively, to evaluate the possibility of using rice hull as an acoustic construction material. The mean sound absorption rates of 10-cm-thick rice hull mats with target densities of $0.10g/cm^3$, $0.12g/cm^3$, and $0.14g/cm^3$ were 0.91, 0.92, and 0.95, respectively, while those of the 1-cm-thick plywood attached to the back of the rice hulls were 0.90, 0.92, and 0.92, respectively. The means of the sound transmission loss of the 10 cm-thick rice hull mats with the target densities of $0.10g/cm^3$, $0.12g/cm^3$, and $0.14g/cm^3$ were 7.66 dB, 10.49 dB, and 14.14 dB, respectively, while those of the 1 cm-thick plywood attached to the back of the rice hulls were 33.34 dB, 36.72 dB, and 38.95 dB, respectively. In conclusion, a rice hull mat could be used as acoustic construction materials because of its high sound absorption coefficient and sound transmission loss.