• Journal of the Korea Concrete Institute
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• v.22 no.3
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• pp.409-417
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• 2010

This paper discusses a series of experiments including material improvement in order to ensure quality of grouting for the post-tensioned structure. In prestressed concrete, grouting refers to the construction procedure of filling empty space of duct enclosing with strands using cementitious material, To date, adequate quality control of the grouting has not been established in Korea because the relationship between the grouting and durability of post-tensioned structure is not well-recognized. The Korean standard does not consider the important material characteristic, wick effect, which is caused by strands in the ducts and current standard testing method unlikely quantify reasonable material segregation. As a result, the grout material, which meets the current material standards, may exhibit excessive bleeding water or shrinkage during construction. In this study, international codes and standards related to grouting were surveyed. The ratio of constituents and novel admixtures were suggested to meet equivalently with these standards. Performance of this enhanced grout was compared to common domestic grout using the international standard testing method. A series of mock-up specimens considering geometry of PC beam was constructed and grout flow pattern was observed as the grout was injected. It was observed that the grouting performance was highly influenced by material properties and filling characteristic can be varied depending on geometry of ducts.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.8
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• pp.1055-1062
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• 2011

The purpose of this study is to develop the shape of photocatalyst-coated module for improve the IAQ, which is installed at inside of ductwork and detachable. Including 3 column types(square, circle, diamond) and 2 fin types(diamond and square), totally 5 types are previously declared for numerical analysis and comparison, 5 types are. As the results of numerical analysis, almost the velocity varied at the range of ${\pm}0.3m$ from the module, except the Type A-3(diamond column type) which is affected to ${\pm}0.4m$ range and shows the biggest velocity differences. Among the 5 types, the diamond fin type(Type B-1) is analyzed as the most stable in velocity. And the results of local pressure drop show that the difference of pressure coefficient of Type B-1 is computed as 0.59, and that of Type A-3 is 2.44. Meanwhile, from the effect analysis of the number of module, the flow conflict happens and the pressure difference between before and after the module increases if there are over 3 modules inserted.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.1005-1012
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• 2011

This research carried out a 3-dimensional simulation using computerized fluid dynamics (CFD) for the flow characteristics, temperature distribution, velocity distribution and residence time, etc. in a reactor in order to derive the optimal combustion conditions of an innovative combustion system. The area-weighted average temperature of the outlet of a furnace during combustion at a condition of fuel input rate 1.5 ton/hr, residence time 1.25 sec and air/fuel ratio 2.1 was $1,077^{\circ}C$, which is a suitable temperature for energy recovery and treatment of air pollutants. Exhaust gas is discharged through a duct at a 40~50 m/s maximum speed along strong vortexes at the center of a combustion chamber, so strong turbulence is created at the center of a combustion chamber to enhance the combustion speed and combustion efficiency. In this system, the optimum operation conditions to prevent incomplete combustion and suppress the formation of thermal NOx were air/fuel ratio 1.9~2.1 and fuel input rate 1.25~1.5 ton/hr.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1712-1717
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• 2009

Capsaicin has been shown to affect lipid metabolism. However, it is currently not known whether capsaicin would lower the intestinal absorption of cholesterol. Thus, this study was conducted to investigate the effect of intraduodenally infused capsaicin on the lymphatic absorption of cholesterol and lipids in rats. Male Sprague-Dawley rats weighing 300-350 g were starved for 16 hr and the mesenteric lymph duct was cannulated. Each rat was infused at 3.0 mL/hr for 8 hr via the duodenal catheter with a lipid emulsion, which contained 33.3 kBq [$^{14}C$]-cholesterol, 20.7 μmol cholesterol, 452 μmol triolein, 3.1 μmol $\alpha$-tocopherol, and 396.0 μmol Na-taurocholate without (control) or with 5.0 mg capsaicin in 24 mL PBS buffer (pH 6.4). Simultaneously, lymph was collected hourly for 8 hr. There was no significant difference in lymph flow between the groups. However, the lymphatic absorption of 14C-cholesterol for 8 hr was significantly lower in rats infused with capsaicin than in those infused with no capsaicin. Also, the output of oleic acid for 8 hr was significantly decreased by capsaicin. However, the intestinal absorption of $\alpha$-tocopherol did not differ between the groups. The results indicate that the luminal infusion of capsaicin inhibits the intestinal absorption of cholesterol and lipids in rats.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.63-67
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• 2000

Purpose: Biliary atresia, one of the major causes of neonatal cholestais, is an idiopathic, serious disorder, affecting the newborn that results in complete obstruction of biliary tract. Successful reestablishment of bile flow is dependent on early surgical intervention, early diagnosis is imperative. The authors evaluate the utility of Tc-99m-labeled diisoprpyliminodiacetic acid (DISIDA) hepatobiliary scintigraphy in the diagnosis of biliary atresia. Methods: From January, 1995 to August, 1999, total 60 patients with neonatal cholestasis underwent Tc-99m DISIDA hepatobiliary scintigraphy at Asan Medical Center. Results: The undelying causes of neonatal cholestasis were biliary atresia in 14, neonatal hepatitis in 33, intrahepatic bile duct paucity in 9, and total parenteral nutrition induced cholestasis in 4. All patient with biliary atresia were interpreted correctely in DISIDA hepatobiliary scintigraphy, showing 100% sensitivity. Of the 46 patients with neonatal hepatitis and other causes, 37 patients had intestinal radioactivity showing 80% specificity. Conclusion: Visualization of DISIDA in the intestinal tract indicates patency of the biliary ducts and excludes the diagnosis of biliary atresia. But the absence of intestinal excretion on the DISIDA hepatobiliary scintigraphy dose not necessarily indicate biliary atresia.

• Food Science and Preservation
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• v.21 no.1
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• pp.91-96
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• 2014

Evidence suggests that dietary indole, particularly rich in cruciferous vegetables, may reduce the risk of cardiovascular diseases. Endosulfan is a residual organochlorine pesticide, which is detected in fruits, vegetables, and crops. In this study, we investigated the effect of luminal indole on endosulfan transport in the small intestine in mesenteric lymph duct-cannulated rats. The duodenum was also cannulated and a fasting phosphate buffered saline-glucose solution was infused overnight at 3 mL/hr. After recovery, a lipid emulsion containing [2,3-$^{14}C$] endosulfan ($^{14}C$-endosulfan) was infused into the duodenum for 8 hours. The tested rats were infused with the same lipid emulsion, but with indole. Samples from the lymph-fistula were collected hourly, and the luminal contents and mucosa were collected at the end of the infusion. The lymph flow in the mesenteric lymph did not differ between the two groups. However, the intestinal absorption of both endosulfan and cholesterol were significantly decreased by indole. The amount of radioactive endosulfan, which remained in the mucosa, was greater in the indole-infused rats due to the decreased transport of endosulfan into the lymph. This study indicates that the indole decreases the intestinal transport of endosulfan into the mesenteric lymph.

• Korean Journal of Clinical Pharmacy
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• v.8 no.2
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• pp.122-132
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• 1998

SB-31 which contains Pursatilla, Licoris and Ginseng extracts was recently proved as an anticancer agent. In a preclinical effort to be applied this drug to human, pharmacokinetics of SB-31 was carried out in rats and rabbits. Glycyrrhizin(GZ), a saponin of Licoris was used as a standard ingradient for the pharmacokinetics of SB-31. The rat's blood, bile and urine samples were serially collected in femoral vein, common bile duct and bladder, respectively, after bolus i.v. injection at a dose of 1 or 1/5 ampul/rat and rabbit's blood samples from the marginal ear vein at a dose of 1 or 3 amp./rabbit. GZ and glycyrrhetic acid(GA), a major metabolite of GZ in the physiological samples were analysed by HPLC with UV detection. The decline of GZ in plasma concentration was generally biexponential at each dose. GZ was almost completely recovered in bile within 18 hour. GA wasn't detected in the samples with UV detector. In the rat, Vss and Kel at a dose of 1 and 1/5 ampul of SB-31 were $98.06\pm6.07\;ml,\;0.33\pm0.05\;hr^{-1}\;and\;65.46\pm11.19\;ml,\;0.68\pm0.25\;hr^{-1}$, respectively. Those in rabbits at a dose of 3 and 1 ampul of SB-31 were $235.24\pm30.72\;ml,\;0.13\pm0.36\;hr^{-1}\;and\;341.32\pm28.58\;ml,\;0.27\pm0.04\;hr^{-1}$, respectively. 'WinNonlin' was utilized for the compartmental analysis. A two-compartment model was chosen as the most appropriate pbarmaco-kinetic model. The data were best described by using a weighting factor of $1/y^2$. To evaluate the effect of SB-31 on cardiovascular system, serially diluted SB-31 was directly injected into coronary artery in the isolated perfused rat heart and the effect of PSF, PSH, saponins of Pursatilla, and SB-31 on PT, APTT of healthy human plasma was examined. Except the positive inotropic effect of ten times diluted solution of SB-31, there was no significant effect on LVDP, (- dp/dt)/(+dp/dt), heart rate and coronary flow in comparision with that of vehicle. SB-31 had no effect on PT but slightly delayed APTT about $6.9{\sim}11.5\%$. There was no significant effect of PSF and PSH on PT & APTT. Conclusively, SB-31 did not show any notable toxic effects on cardiovascular system.

• Journal of Integrative Natural Science
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• v.16 no.1
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• pp.13-31
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• 2023

The sesarmid crab Muradium tetragonum, inhabiting the mangrove, are considered as a key consumer of litter and thereby play an important role in the detritus food chain and energy flow in the mangrove ecosystem. The present investigation was carried out with objectives to enlighten the reproductive system of Muradium tetragonum through histological and histochemical studies. Histological organization of the testis of M. tetragonum revealed that each testis has a lobular structure consisting of several testicular lobules arranged around the collecting duct. Histology of the deferens of M. tetragonum revealed it to be composed of three-layer of tissues along the entire length:the outer connective tissue, the middle muscular and the inner epithelial layer. Based on the histological architecture these three regions are recognized as proximal vas deferens (PVD), middle vas deferens (MVD) and distal vas deferens (DVD). Histological characteristics of the ovary of M. tetragonum during different phases of ovarian development were studied. Based on the colour changes of the ovary and diameter of the oocytes five stages of ovarian development can be pronounced. Histochemical analysis of the male reproductive tissues of M. tetragonum signifies the secretion of a different biomolecule by specifying their origin in the reproductive tissue and their possible transformation into spermatophores. In the female reproductive tissues, histochemical evaluation envisaged the secretory products during different stages of ovarian development The secretory substances of the spermatheca expound on the significance of its secretion in dehiscing the spermatophore wall and in nourishing as well as protecting the spermatozoa.

• Journal of the Korean Society of Radiology
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• v.83 no.5
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• pp.991-1002
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• 2022

Biliary atresia is a rare but significant cause of neonatal cholestasis. An early and accurate diagnosis is important for proper management and prognosis. To diagnose biliary atresia, various imaging studies using ultrasonography, MRI, hepatobiliary scans, and cholangiography can be performed, although ultrasonography is more important for initial imaging studies. In this article, we review the findings of biliary atresia from various imaging modalities, including ultrasonography, MRI, hepatobiliary scans, and cholangiography. The known key imaging features include abnormal gallbladder size and shape, periportal thickening visible as a 'triangular cord' sign, invisible common bile duct, increased hepatic arterial flow, and combined anomalies. Aside from the imaging findings of biliary atresia, we also reviewed the diagnostic difficulty in the early neonatal period and the role of imaging in predicting hepatic fibrosis. We hope that this review will aid in the diagnosis of biliary atresia.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.1
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• pp.39-46
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• 2011

NO oxidation is an important prerequisite step to assist the selective catalytic reduction (SCR) at low temperatures ($<200^{\circ}C$). Therefore, we conducted the lab- and bench-scales experiments appling the sodium chlorite powder ($NaClO_2(s)$) for the oxidation of NO to $NO_2$ and the carbon-based catalyst for the reduction of $NO_x$ and $SO_2$; the lab- and bench-scales experiments were conducted in laboratory and iron-ore sintering plant, respectively. In the lab-scale experiment, known concentrations of $NO_x$ (200 ppm), $SO_2$ (75 ppm), $H_2O$ (10%) and $NH_3$ (400 ppm) in 2.6 L/min were introduced into a packed-bed reactor containing $NaClO_2(s)$, then gases produced by the reaction with $NaClO_2(s)$ were fed into the carbon-based catalyst (space velocity = $2,000hr^{-1}$) at $130^{\circ}C$. In the bench-scale experiment, flue gases of $50Nm^3/hr$ containing 120 ppm NO and 150 ppm $SO_2$ were taken out from the duct of iron-ore sintering plant, then introduced into the flow reactor; $NaClO_2(s)$ were injected into the flow reactor using a screw feeder. Gases produced by the reaction with $NaClO_2(s)$ were introduced into the carbon-based catalyst (space velocity = $1,000hr^{-1}$). Results have shown that, in both lab- and bench-scales experiments, NO was oxidized to $NO_2$ by $NaClO_2(s)$. In addition, above 90% of $NO_x$ and $SO_2$ removal were obtained at the carbon-based catalyst. These results lead us to suggest that the combination of $NaClO_2(s)$ with the carbon-based catalyst has the potential to achieve the simultaneous removal of $NO_x$ and $SO_2$ at low temperature ($<200^{\circ}C$).