• International Journal of Naval Architecture and Ocean Engineering
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• v.2 no.1
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• pp.1-13
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• 2010

A comparative study between a computation and an experiment has been conducted to predict the performance of a Pod type waterjet for cm amphibious wheeled vehicle. The Pod type waterjet has been chosen on the basis of the required specific speed of more than 2500. As the Pod type waterjet is an extreme type of axial flow type waterjet, theoretical as well as experimental works about Pod type waterjets are very rare. The main purpose of the present study is to validate and compare to the experimental results of the Pod type waterjet with the developed CFD in-house code based on the RANS equations. The developed code has been validated by comparing with the experimental results of the well-known turbine problem. The validation also extended to the flush type waterjet where the pressures along the duct surface and also velocities at nozzle area have been compared with experimental results. The Pod type waterjet has been designed and the performance of the designed waterjet system including duct, impeller and stator was analyzed by the previously mentioned m-house CFD Code. The pressure distributions and limiting streamlines on the blade surfaces were computed to confirm the performance of the designed waterjets. In addition, the torque and momentum were computed to find the entire efficiency and these were compared with the model test results. Measurements were taken of the flow rate at the nozzle exit, static pressure at the various sections along the duct and also the nozzle, revolution of the impeller, torque, thrust and towing forces at various advance speed's for the prediction of performance as well as for comparison with the computations. Based on these measurements, the performance was analyzed according to the ITTC96 standard analysis method. The full-scale effective and the delivered power of the wheeled vehicle were estimated for the prediction of the service speed. This paper emphasizes the confirmation of the ITTC96 analysis method and the developed analysis code for the design and analysis of the Pod type waterjet system.

• Tuberculosis and Respiratory Diseases
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• v.44 no.1
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• pp.183-190
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• 1997

Tocolytics are agents widely used in the treatment of premature labor to inhibit uterine contractions. Ritodrine is most commonly used tocolytic agent and acts by increasing intracellular cyclic adenosine monophosphate, which decreases the activity of myosin light-chain kinase, the rate-limiting enzyme in the signal network leading to contraction. Physiologic effects associated with the use of ritodrine are due to their effect on bera-l as well as beta-2 receptors. Some of maternal complications of therapy are rachycardia, hyperglycemia, hypokalemia, lactic acidosis, myocardial ischemia, and pulmonary edema. Tocolytics induced pulmonary edema is a serious complication that can lead to marternal death, although infrequent, The incidence varies from 0.5% to 5% of those receiving these agents. Predisposing factors include the concommitant use of corticosteroid, twin gestation, fluid overload (particularly with saline), and anemia. Several mechanisms have been postulated, but the pathogenesis is uncertain. It is suggested that both types of mechanism, hydrostatic and permeability induced, might be involved. The association of tocolytic therapy with pulmonary edema appears to be unique to the pregnant state, because this complication has never been reported in asthmatic patients exposed to high dosages. We report a case of tocolytic induced pulmonary edema developed in 24 hours after delivery.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5350-5355
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• 2012

Human tyrosinase (hTyr) catalyzes the first and rate limiting step in the biosynthesis of a skin color determinant, melanin. Although a number of cosmetic companies have tried to develop hTyr inhibitors for several decades, absence of 3D structure of hTyr make it impossible to design or screen inhibitors by structure-based approach. Therefore, we built a 3D structure by comparative modeling technique based on the crystal structure of tyrosinase from Bacillus megaterium to provide structural information and to search new hit compounds from database. Our model revealed that two copper atoms of active site located deep inside and were coordinated with six strictly conserved histidine residues coming from four-helix-bundle. Substrate binding site had narrow funnel like shape and its entrance was wide and exposed to solvent. In addition, hTyr-tyrosine and hTyr-kojic acid, a well-known inhibitor, complexes were modeled with the guide of solvent accessible surface generated by in-house software. Our model demonstrated that only phenol group or its analogs could fill the binding site near the nuclear copper center, because inside of binding site had narrow shape relatively. In conclusion, the results of this study may provide helpful information for designing and screening new anti-melanogenic agents.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.537-543
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• 1999

Whole horse beans (Vicia faba cv. Alfred) (WHB) were pressure toasted at different temperatures of 100, 118 and $136^{\circ}C$ for 3, 7, 15 and 30 minutes in order to determine an optimal heating conditions to increase bypass starch (BPSt) as glucose source which is usually limiting nutrient in highly producing dairy cows in the Netherlands. Starch (St) Ruminal Degradative Kinetics and Fermentation Characteristics of (SRDC) of WHB were determined using in sacco technique in 4 lactating dairy cows fed 47% hay and 53% concentrate according to Dutch dairy cow requirements. Measured characteristics of St were soluble fraction (S), potentially degradable fraction (D) and rate of degradation (Kd) of insoluble but degradable fraction. Based on measured characteristics, percentage bypass starch (BPSt) was calculated according to the Dutch new feed evaluation system: the DVE/OEB system. Pressure toasting temperatures significantly affected starch gelatinization (p<0.01). Degradability of Starch in the rumen was highly reduced by pressure toasting (p<0.01). S varied from 58.2% in the raw WHB (RWHB as a control) to 19.6% in $136^{\circ}C/15min$. S was reduced rapidly with increasing time and temperature (p<0.01). D varied from 41.8% in RWHB to 80.5% in $136^{\circ}C/15min$. D fraction was enormously increased with increasing time and temperature (p<0.01). Kd varied from 4.9%h in RWHB to 3.4%/h in $136^{\circ}C/15min$. All these effects resulted in increasing %BPSt from 29.0% in RWHB to 53.1% in $136^{\circ}C/15min$. Therefore BPSt increased from 93.5 g/kg in RWHB to 173.5 g/kg in $136^{\circ}C/15min$. The effects of pressure toasting on %BPSt and BPSt seemed to be linear up to the highest values tested. Therefore no optimal pressure toasting conditions could be determined at this stage. But among 10 treatments, The treatment of $136^{\circ}C/15min$was the best with the highest BPSt content. It was concluded that pressure toasting was effective in shifting starch degradation from rumen to small intestine to increase bypass starch.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.503-509
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• 1998

Whole faba beans (WFB) were dry roasted at different temperatures of 110, 130 and $150^{\circ}C$ for 15, 30 and 45 minutes (min) to determine the optimal heating conditions to increase bypass starch as glucose source which may be a limiting nutrient in high producing dairy cattle. Ruminant degradation characteristics of starch (St) of WFB were determined using in sacco method in 6 dairy cows fed 60% hay and 40% concentrate. Measured characteristics of St were soluble (washable) fraction (S), potentially degradation fraction (D) and the rate of degradation (Kd) of the insoluble but degradable St fraction. Based on measurement of these characteristics, percentage bypass starch (%BSt) and bypass starch (BSt) were calculated. Degradability of starch in the rumen was reduced by dry roasting at temperature of 130 and $150^{\circ}C$ and increased at $110^{\circ}C$. S varied from 50.0% in the raw whole faba beans (RWFB) and 53.7% in $110^{\circ}C$/15 min to 18.2% in $150^{\circ}C$/45 min. D varied from 49.9% in RWFB and 46.3% in $110^{\circ}C$/15 min to 81.8 % in $150^{\circ}C$/45 min. Kd varied from 9.8% in RWFB and 11.0% in the $110^{\circ}C$/30 min to 4.2 in $150^{\circ}C$/45 min. All these effects resulted in increasing %BSt from 22.1% in the $110^{\circ}C$/45 min and 23.9% in RWFB to 49.9% in the $150^{\circ}C$/45 min. Therefore BSt increased from 91.4 g/kg and 98.4 g/kg to 199.9 g/kg respectively. Dry roasting at $110^{\circ}C$ increased the starch rumen degradation. Treatment at higher temperature (130 and $150^{\circ}C$) decreased rumen degradation of starch and seemed to be linear up to highest values tested. No optimal dry roasting conditions of treatment could be determined at this stage. It may be concluded that dry roasting at temperatures of 130 and $150^{\circ}C$ was effective in shifting starch degradation from rumen to intestine to increase bypass starch.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.144-151
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• 2017

This study examined the anti-inflammatory and whitening effects of Amaranth (Amaranthus spp L.) seed extract. Amaranthus spp L. seeds were extracted using 70% ethanol and then fractionated sequentially with n-hexane, dichloromethan, ethyl acetate and butanol. For the study of anti-inflammatory activity in RAW 264.7 cells, EtOAc fraction of Amaranthus spp L. seeds significantly inhibited nitrogen oxide production as well as the protein level of iNOS. Furthermore, EtOAc fraction of Amaranthus spp L. seeds inhibited expression of $TNF-{\alpha}$, PGE2 and the protein level of COX-2 in a dose-dependent manner. Inaddition, the tyrosinase inhibitory activities of the Amaranthus spp L. seed 70% ethanol extract and subfractions were also measured to see if these extracts can be used as an ingredient for whitening cosmetics. Tyrosinase is an oxidase that is a rate-limiting enzyme for controlling the production of melanin. Therefore, tyrosinase inhibitors have become increasingly important in cosmetics and medical products with regards to hyperpigmentation. EtOAc fraction of Amaranthus spp L. seeds showed mushroom tyrosinase inhibitory activity in a dose-dependent manner. This activity was more potent than that of a positive control cynandione A. These results suggest that Amaranthus spp L. seeds may be a valuable natural ingredient for the food and cosmetics industries.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.2
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• pp.33-41
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• 2018

Large amounts of leaves from street trees fall onto the streets annually and need to be cleaned and treated. Cherry trees are common street trees in Korea. The adsorption characteristics of Pb(II) by cherry leaf (CL) and cherry leaf-derived biochar (CB) were studied through a series of batch experiments. CB was produced through the carbonization of CL at $800^{\circ}C$ for 90 min. Carbonization increased the C content and pH value, while decreased H and O contents. Well developed pore structure was observed at the surface of CB. The pseudo-second order model better described the kinetics of Pb(II) adsorption onto CL and CB, indicating that the rate-limiting step of the heavy metal sorption is chemical sorption. Fast adsorption rates and high adsorption capacities were obtained by the carbonization from CL to CB. Langmuir models better adequately described the Pb(II) adsorption onto CL and CB. Maximum adsorption capacities of Pb(II) expressed by Langmuir constant, $Q^0$ were 37.31 mg/g and 94.34 mg/g, when CL and CB were used as adsorbents, respectively.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.5
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• pp.595-605
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• 2000

Dental ceramics have good aesthetics, biocompatibility, low thermal conductivity, abrasion resistance, and color stability. However poor resistance to fracture and shrinkage during firing process have been limiting factors in their use, particularly in multiunit ceramic restorations. A new method for making all-ceramic crowns that have high strength and low processing shrinkage has been developed and is referred to as the Vita In-Ceram method. This study was performed to investigate the effect of $CeO_2$ addition in borosilicate glasses on the strength of alumina-glass composites. Porous alumina compacts were prepared by slip casting and sintered at $1,100^{\circ}C$ for 2 hours. Dense composites were made by infiltration of molten glass into partially sintered alumina at $1,140^{\circ}C$ for 4 hours. Specimens were polished sequentially from #800 to #2000 diamond disk. and the final surface finishing on the tensile side was received an additional polishing sequence through $1{\mu}m$ diamond paste. Biaxial flexure test was conducted by using ball-on-three-ball method at a crosshead speed of 0.5mm/min. To examine the microstructural aspect of crack propagation in the alumina-glass composites, Vickers-produced indentation crack was made on the tensile surface at a load of 98.0 N and dwell time of 15 sec, and the radial crack patterns were examined by an optical microscope and a scanning electron microscope. The results obtained were summarized as follows; 1. The porosity rates of partially sintered alumina decreased with the rising of firing temperature. 2. The maximum biaxial flexure strength of 423.5MPa in alumina-glass composites was obtained with an addition of 3 mol% $CeO_2$ in glass composition and strength values showed the aspect of decrease with the increase of $CeO_2$ content. 3 The biaxial flexure strength values of alumina-glass composites were decreased with rising the firing temperature. 4. Observation of the fracture surfaces of alumina-glass composites indicated that the enhancement of strength in alumina-glass composites was due to the frictional or geometrical inter-locking of rough fracture surfaces and ligamentary bridging by intact islands of materials left behind the fracture front.

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1011-1018
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• 1997

Background : To evaluate how efficaciously and safely we can make transthoracic lung biopsy with an 18-gauge automated biopsy device. Methods : We performed 130 transthoracic needle biopsies including 16 repeat biopsies in 114 patients with a pulmonary mass using an l8-gauge biopsy device (ASAP 18, Microvasive-. Eighty-three biopsies were performed by an experienced radiologist and 47 by several less experienced radiologists. All biopsies were guided by biplane fluoroscopy. Results : We successfully obtained sufficient tissue(>2-mm in the length) in 128(985) of 130 biopsies. Biopsy provided the specific diagnosis in 97 (85%) of 114 patients including 78 (88%) of 89 patients with a malignant tumor and 19 (90%) of 21 patients with a benign condition. The diagnosis could not be made in the remaining four patients. Of interest to note was the superb capability (74/74) of biopsy to make a distinction between small cell carcinoma and non-small cell carcinoma. There was no significant difference in the diagnostic yields between the experienced and less experienced radiologists. Of the total 130 biopsies, pneumothorax appeared in 13 (10%), among which treatment was required in 2 (2%), Mild, self-limiting hemoptysis was nod in seven (5%), but in no case was the treatment required. Conclusion : We conclude transthoracic lung biopsy with an 18-gauge automated device is an effective procedure for the specific diagnosis of benign and malignant lung disease. It is safe with the complication rate comparable to that of fine-needle aspiration biopsy as well.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.492-496
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• 2001

Microsomal triglyceride transfer protein(MTP) activity and mRNA level were investigated in the liver and small intestine of rats fed on di-(2-ethylhexyl)phthalate(DEHP) and orotic acid(OA) as serum triglyceride-reducing agents. The concentration of liver triglyceride was significantly increased in the OA group, but that was not increased in the DEHP group compared with the control group. The concentration of serum triglyceride was significantly decreased in the OA and DEHP groups compared with the control group, but this reduction was more pronounced in the OA group. MTP activity and mRNA level in liver were decreased in the OA group compared with the control group, while MTP activity in the small intestine was increased in the OA group compared with the control group. MTP activities and MTP mRNA levels in both liver and small intestine had no influence by the DEHP dietary feeding, despite the triglyceride-lowering action, compared with the control dietary feeding. The activity of liver microsomal phosphatidate phosphohydrolase(PAP), the rate-limiting enzyme in triglyceride synthesis, was increased in the OA group compared with the control group, but that of cytosolic PAP was decreased in the DEHP group compared with the control group. The result suggest that MTP activity and MTP mRNA level are involved in the triglyceride-lowering action of OA, but those are not involved in that of DEHP.