• Title/Summary/Keyword: Centrifugal

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A Study on the Utilization of Trichoxanthes Kirilowii Root Starch (하늘타리(Trichoxanthes Kirilowii)의 자원화(資源化)에 관한 기초(基礎) 연구(硏究))

  • Koh, Jeong-Sam
    • Applied Biological Chemistry
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    • v.24 no.1
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    • pp.59-66
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    • 1981
  • Trichoxanthes Kirilowii with high starch-content was investigated to utilize as a food source. The weight and starch content of Trichoxanthes Kirilowii roots increased rapid1y in proporion to the growth period. The seasonal variations of the starch content were $36.5{\sim}48.0%$ (dry basis) from June to December. The chemical properties of natural growth soils of Trichoxanthes Kirilowii contained more organic matter and total nitrogen content than citrus orchard soils, but less mineral; P,K,Ca and Mg. To prepare starch with the plant root, the centrifugal method(3,000 rpm, 20 min) obtained the highest yield. The industrial-scale method, was similar to the processing of sweetpotato starch (tank precipitation method), and was good in quality. The starch granules were mainly spherical with diameters ranging from $5{\sim}16{\mu}$. The density of the starch was 1.535 and amylose content was about 26.7%. The X-ray diffraction pattern showed that the granules were of the B-type. The blue value of starch, amylose and amylopectin was 0.46, 0.80 and 0.18, respectively. The starch contained 0.05% ash, 0.35% crude protein and 34 mg% phosphorus. and had an inital pasting temperature of $63.5^{\circ}C$. The color intensity of the starch which iodine gave rise to absorption maxima at 670nm. The starch paste showed high stability during cold storage at $5^{\circ}C$.

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Effects of Controlled Photoperiod on Body Development in Growing Juvenile Rats

  • Lee, Seung-Hoon;Lee, Han-Ki;Shin, Jin-Hee;Hong, Yun-Kyung;Lee, Sang-Kil;Lee, Sang-Un;Suzuki, Takao;Kang, Tae-Young;Hong, Yong-Geun
    • Reproductive and Developmental Biology
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    • v.34 no.2
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    • pp.89-94
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    • 2010
  • Melatonin is induced by light information through the retina and leads to growth factor activation. Thus, we investigated the effects of melatonin by controlling the photoperiod of growing young rats. Male Sprague-Dawley rats (n=6; 4 weeks old) were divided into two experimental groups: the L/D group (normal photoperiod; light/dark: 12/12 h; lights on at 9:00 a.m.) and the L/L group (light/light: 24 h). Rat body weight and food consumption were measured daily for 8 weeks. After 8 weeks, the rats were anesthetized with a mixture of ketamine (50 mg/kg) and xylazine (10 mg/kg) and sacrificed. Tissue was then collected for RNA isolation (from brain, heart, liver, kidney, adrenal gland, testis, tibia, hind limb muscles). Also, serum was isolated from blood using a centrifugal separation. The L/L group had significantly lower body weight than the L/D group from 4 to 6 weeks (p<0.05). The L/D group had increased tissue mass, compared with the L/L group, but the difference was not statistically significant. The L/D group had a significantly higher melatonin concentration than the L/L group between the hours of midnight and 2:00 a.m (p<0.01). These results indicate that photoperiod length may affect the secretion of melatonin from the pineal gland. Also, the reduction of nocturnal melatonin secretion may retard the development of growing young rats. In future studies, we plan to compare exogenous melatonin administration with endogenous melatonin concentration induced by photoperiod control. Moreover, we will confirm whether the effects seen in pathological animal models can be reversed by controlling the photoperiod.

Aerodynamic Characteristics Analysis of Small Two-Stage Turbo Blower Using CFD (CFD를 이용한 소형 2단 터보블로워의 공력해석)

  • Seo, Seungjae;Ryu, Minhyoung;Cho, Leesang;Cho, Jinsoo
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.42 no.4
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    • pp.326-335
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    • 2014
  • Aerodynamic characteristics of the small two-stage turbo blower were investigated using commercial CFD tool(ANSYS CFX Ver. 14.5) in this paper. Turbo blower, which is a centrifugal type of turbomachinery, is used in various industries. It is used for application that required high static pressure rising at relatively small volumetric flow rate. In order to understand the mechanism of static pressure rising, the aerodynamic characteristics of the small two-stage turbo blower are analyzed at high rotating speed in this study. The k-${\omega}$ SST turbulence model, which is good at prediction of adverse pressure gradient flows, was applied. The CFD results of the turbo blower are validated by performance test. The static pressure rising of the turbo blower is nonlinearly increased over the first stage and the second stage. The secondary flow occurred at guide vanes, between the casing and the first impeller shroud, and the bottom of the impeller disk. As a result, It is required that whole fluid area is analyzed to predict aerodynamic characteristics of small two-stage turbo blower. and the result should be selected with considering for error from experiment and CFD.

Electron Microscopical Property of Transglutaminase Added Milk (트랜스글루타미나제를 첨가한 우유의 전자현미경적 특성)

  • 문정한;홍윤호
    • Food Science of Animal Resources
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    • v.23 no.4
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    • pp.350-355
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    • 2003
  • Raw skim milk and colloidal calcium phosphate-free skim milk were treated with microbial transglutaminase (TGase), ultracentrifuged at varying rates and were observed to contain textural properties using a scanning electron microscope (SEM). Skim milk showed irregular signs of conformation at lower centrifugal rate, and associated regular (10,000 ${\times}$g) and thin with broad holes (20,000 ${\times}$g). The associated texture became thick and irregular (40,000 ${\times}$g), and fine particles were regularly associated (100,000 ${\times}$g). When skim milk was incubated for 1 hr with TGase, casein micelles aggregated and broadened as centrifugation rate increased. When skim milk was incubated for 8 hrs with TGase, casein micelles associated to large widened aggregates, and were associated regularly which then became irregular (100,000 ${\times}$g). When colloidal calcium phosphate-free skim milk incubated for 1 hr with TGase showed no sediment, the milk incubated for 8 hrs with TGase associated together, yielding broadened and regular layers as the centrifugation rate increased. It is assumed that such phenomena could be caused by protein crosslinking reaction with TGase and conformational change of casein molecules, as well as dependencies on reaction time, temperature and ultracentrifugation rate.

Effect of Fermented Platycodon grandiflorum Extract on Cell Proliferation and Migration in Bovine Aortic Endothelial Cells (혈관내피세포의 성장 및 세포 이동에 영향을 미치는 발효도라지추출물의 효과)

  • Choi, Woosoung;Song, Jina;Park, Mi-Hyeon;Yu, Heui Jong;Park, Heonyong
    • Journal of Life Science
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    • v.26 no.1
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    • pp.59-67
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    • 2016
  • Platycodon grandiflorum A. De Candolle (Korean name, ‘Doraji’) is a perennial plant containing various triterpenoid saponins. The roots of this plant have traditionally been used as a food material in Korea. Here, we prepared a fermented P. grandiflorum extract (PG). Although it was previously reported that P. grandiflorum A. extract has a variety of physiological functionalities, including anti-inflammatory and anti-oxidant activities, little is known about its vascular functions. In this study, we executed a series of experiments to identify the effect of PG on endothelial cells. PG at a high concentration (100 μg/ml) was found to induce cell detachment, whereas PG at a low concentration (0.1 μg/ml) appeared to promote cell proliferation and migration in bovine aortic endothelial cells. The cell detachment induced by the high concentration was not associated with cell death, such as apoptosis, necrosis, and autophagy. In addition, we found that PG at the high concentration formed a small vesicular structure called an endothelial microparticle (EMP). The EMP was prepared by centrifugal fractionation and determined with flow cytometry and a microscope. Interestingly, PG-induced cell detachment was found to be mediated by EMP. We furthermore determined that PG at the low concentration activated Akt, a crucial cell-signaling molecule, and then controlled cell proliferation and migration. Overall, our findings suggest that PG at low doses maintains vascular stability by promoting endothelial cell proliferation, and enhances the efficacy of wound healing by cell proliferation and migration activity.

Antibacterial Effect of Bacteria Isolated from the Plant Rhizosphere against Pathogenic Bacteria of Fish (식물근권에서 분리한 세균의 어류질병세균에 대한 항균활성 효과)

  • Jeong, Ji-Woon;Park, So-Hyun;Kim, Dong-Hwi;Jeun, Yong-Chull;Heo, Moon-Soo
    • Journal of Life Science
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    • v.24 no.7
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    • pp.757-761
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    • 2014
  • Olive flounder (Paralichthys olivaceus) is an important aquaculture fish species in Jeju Island, South Korea. Due to the intensification of flounder fish farming, huge amounts of chemical antibiotics are used against several fish diseases. This has many harmful side effects on fish, as well as human consumers. Hence, an alternative to chemical antibiotic agents is needed for disease control. In this study, three strains of rhizobacteria (BRH433-2, TRH415-2, and THJ609-3) were isolated from the rhizosphere of plants. Assays of their antibacterial activity against fish pathogens, such as S. iniae, S. parauberis, V. anguillarum, and E. tarda, were performed with untreated broth culture (without cell separation), supernatant, and precipitated pellets separated by centrifugation. Among these, the cell suspension prepared from the precipitated pellet showed significant antimicrobial activity when compared with that of the untreated broth culture and centrifugal supernatant. These results indicate that the three isolated rhizobacterial strains exhibit antibacterial activity. Analysis of the 16S rDNA sequences of the BRH-433-2, THJ609-3, and TRH415-2 strains showed the highest similarity to Burkholderia gladioli (99.5%), Pseudomonas baetica (97.7%), and P. koreensis and P. baetica (98.4%), respectively. We suggest that the strains hold promise in disease management of fish.

CERAMIC INLAY RESTORATIONS OF POSTERIOR TEETH

  • Jin, Myung-Uk;Park, Jeong-Won;Kim, Sung-Kyo
    • Proceedings of the KACD Conference
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    • 2001.05a
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    • pp.235-237
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    • 2001
  • ;Dentistry has benefited from tremendous advances in technology with the introduction of new techniques and materials, and patients are aware that esthetic approaches in dentistry can change one's appearance. Increasingly. tooth-colored restorative materials have been used for restoration of posterior teeth. Tooth-colored restoration for posterior teeth can be divided into three categories: 1) the direct techniques that can be made in a single appointment and are an intraoral procedure utilizing composites: 2) the semidirect techniques that require both an intraoral and an extraoral procedure and are luted chairside utilizing composites: and 3) the indirect techniques that require several appointments and the expertise of a dental technician working with either composites or ceramics. But, resin restoration has inherent drawbacks of microleakage. polymerization shrinkage, thermal cycling problems. and wear in stress-bearing areas. On the other hand, Ceramic restorations have many advantages over resin restorations. Ceramic inlays are reported to have less leakage than resin restoration and to fit better. although marginal fidelity depends on technique and is laboratory dependent. Adhesion of luting resin is more reliable and durable to etched ceramic material than to treated resin composite. In view of color matching, periodontal health. resistance to abrasion, ceramic restoration is superior to resin restorationl. Materials which have been used for the fabrication of ceramic restorations are various. Conventional powder slurry ceramics are also available. Castable ceramics are produced by centrifugal casting of heat-treated glass ceramics. and machinable ceramics are feldspathic porcelains or cast glass ceramics which are milled using a CAD/CAM apparatus to produce inlays (for example, Cered. They may also be copy milled using the Celay apparatus. Pressable ceramics are produced from feldspathic porcelain which is supplied in ingot form and heated and moulded under pressure to produce a restoration. Infiltrated ceramics are another class of material which are available for use as ceramic inlays. An example is $In-Ceram^{\circledR}$(Vident. California, USA) which consists of a porous aluminum oxide or spinell core infiltrated with glass and subsequently veneered with feldspathic porcelain. In the 1980s. the development of compatible refractory materials made fabrication easier. and the development of adhesive resin cements greatly improved clinical success rates. This case report presents esthetic ceramic inlays for posterior teeth.teeth.

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The Heat Pump Application to the Food Concentration (열 펌프의 식품 농축에의 이용 연구)

  • Park, Noh-Hyun;Kim, Byeong-Sam;Kang, Tong-Sam;Shin, Dong-Hwa
    • Korean Journal of Food Science and Technology
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    • v.19 no.6
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    • pp.486-491
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    • 1987
  • The performance and applicability to food concentration of heat pump were investigated. During heating the water of spa from $43^{\circ}C$ to $51^{\circ}C$, COP's of heat pump (R-12, 150 HP) were 4.03 at heating part and 3.5 at cooling part. And, the efficiency of compressor (${\alpha}$) was 0.477 While the city water was heated to $39^{\circ}C$ by heat pump (R-22, 10 HP), its COP's were 3.0 at heating part and 1.87 at cooling part. During concentrations sucrose solution by centrifugal evaporator (ALFA-LAVAL CO, CTIB) with heat pump, heat capacity for condensating water vapor was required greater 15% than the latent heat for concentrating and then the overall heat transfer coefficient was $1196\;Kcal/m^{2}.\;h.\;^{\circ}C$. When low temperature concentration ($30-35^{\circ}C$, 28-40 Torr) of garlic extract was carried out by the water of $60^{\circ}C$ and $15^{\circ}C$ adjusted by heat pump, the ratio of heat capacity for concentrating vs. that for condensating of water vapor was 0.961.

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Physicochemical properties and anti-wrinkle effect of polysaccharides with different molecular weights from Gloiopeltis furcata (불등풀가사리 다당류의 분자량에 따른 이화학적 품질특성 및 피부 주름 개선 효과)

  • Lee, Dae-Hoon;Hong, Joo-Heon
    • Food Science and Preservation
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    • v.24 no.5
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    • pp.688-696
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    • 2017
  • In this study, the physicochemical properties and anti-wrinkle effect of polysaccharides with different molecular weights from Gloiopeltis furcata were investigated. Crude polysaccharides were isolated by viscozyme treatment followed by ethanol precipitation and lyophilization. Crude polysaccharides were hydrolyzed by acid (0.1 N HCl) and the molecular weight fractions were generated by centrifugal filter (<10 kDa, 10 to 100 kDa, and 100 kDa>). The yield of polysaccharides with different molecular weight fractions was 8.4-39.6%. The major constituents in molecular weight fractions were total sugar (81.37-85.82%), uronic acid (27.89-32.85 g/100 g), sulfate (33.38-39.04%), and protein (0.35-3.16%) The L, a, and b value of the 100 kDa group were decreased, but viscosity increased. The oxygen radical absorbance capacity of the 100 kDa group at $180.07{\mu}M$ was the highest among groups. The protective effects of 100 kDa group at 0.5 and $5{\mu}g/mL$ against $H_2O_2$-induced cytotoxicity in L132 cell were 87.34% and 103.85%, respectively. The matrix metalloproteinase-1 activity of 100 kDa group decreased in a dose-dependent manner. The pro-collagen synthesis activity of 100 kDa group at $0.05-0.5{\mu}g/mL$ was 64.91-77.80%. The polysaccharides with different molecular weights from Gloiopeltis furcata investigated herein are useful as a potential candidate for cosmedical materials.

Kinematical Analysis of Basket with 1/2 Turn to Handstand on Parallel Bars (평행봉 Basket with 1/2 Turn to Handstand 기술 분석)

  • Back, Jin-Ho;Park, Jong-Chul;Lee, Yong-Sik
    • Korean Journal of Applied Biomechanics
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    • v.17 no.1
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    • pp.165-174
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    • 2007
  • The subject of this study was male apparatus gymnastics athlete who had scored high points doing basket with 1/2 turn on parallel bars. Then 3D motion analysis were used to calculate & analyse kinematic variables of Basket with 1/2 turn to Handstand. 1. The total average time spent for Basket with 1/2 turn took $2.16{\pm}.08sec$, at the downward upward phase took $.58{\pm}0.00sec$, $.23{\pm}.00sec$, at flight phase took $.28{\pm}.01sec$, at connected area phase took $.72{\pm}0.21sec$, at rotation area phase took $.35{\pm}.14sec$. To have a successful performance, there should be faster speed and velocity to rotate at the downward upward phase, then the upward velocity and height must be used adequately. Moreover, the speed must be faster at the flight connect phase to stabilize Center of Mass(CM) for the body, and must secure more time at the rotation area to have more stable performance. 2. After handstand on parallel bars while moving CM to right hand side, and It must be performed with big and magnificent performance with putting both hand's center to far away from the parallel bars. 3. Furthermore, CM must be moved fast from downwards to right hand side, and CM must be moved fast in vertical movement at upward and flight phase to avoid CM from moving back and forth, and left and right. 4. At downwards, the subject must rotate as bis as possible using hip-joint as wide as possible and at upwards, must put his body to vertical to have stable performance. While rotating or turning, it is better to do with bigger shoulder angle and have to make sure that trunk angle must be not scattered. To perform better and more positive in basket with 1/2 turn on parallel bars, the centrifugal force must be used big and fast at downward, and at upward and flight phase, downward movement must change to vertical movement as soon as possible while turning movement must happen at handstand position. Time spent must be shorten at connected area to stabilize CM and turning must be natural as possible while securing the necessary time of movement to well-balanced. Also, the body must be vertically closed from the ground.