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Aerosol Deposition and Its Potential Use for Bioactive Ceramic Coatings

  • Hahn, Byung-Dong;Park, Dong-Soo;Lee, Jeong-Min;Choi, Jong-Jin;Ryu, Jung-Ho;Yoon, Woon-Ha;Lee, Byoung-Kuk;Choi, Joon-Hwan;Kim, Hyoun-Ee
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2009년도 추계학술발표대회
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    • pp.41.1-41.1
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    • 2009
  • Aerosol Deposition (AD) is anovel way to fabricate bioactive ceramic coatings in biomedical implants and prostheses applications. In the present work, silicon-substituted hydroxyapatite (HA) coatings on commercially pure titanium were prepared by aerosol deposition using Si-HA powders. The incorporation of silicon in the HA lattice is known to improve the bioactivity of the HA, makingsilicon-substitute HA an attractive alternative to pure HA in biomedical applications. Si-HA powders with the chemical formula $Ca_{10}(PO_4)_6-x(SiO_4)x(OH)_2-x$, having silicon contents up to x=0.5 (1.4 wt%), were synthesized by solid-state reaction of $Ca_2P_2O_7$, $CaCO_3$, and $SiO_2$. The Si-HA powders were characterized by X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), and Fourier transform infrared spectroscopy(FT-IR). The corresponding coatings were also analyzed by XRD, scanning electron microscopy (SEM), and electron probe microanalyzer (EPMA). The results revealed that a single-phase Si-HA was obtained without any secondary phases such as $\alpha$- or $\beta$-tricalcium phosphate (TCP) for both the powders and the coatings.The Si-HA coating was about $5\;{\mu}m$ thick, had a densemicrostructure with no cracks or pores. In addition, the proliferation and alkaline phosphatase (ALP) activity of MC3T3-E1 preosteoblast cells grown on the Si-HA coatings were significantly higher than those on the bare Ti and pure HA coating. These results revealed the stimulatory effects induced by siliconsubstitution on the cellular response to the HA coating.

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Phosphatidylcholine과 Sodium Deoxycholate가 지방세포 생존에 미치는 영향의 비교 분석 (Comparative Analysis about the Effect of Isolated Phosphatidylcholine and Sodium Deoxycholate for the Viability of Adipocyte)

  • 나은영;강조아;이중호;오득영;서제원;문석호;안상태;이종원
    • Archives of Plastic Surgery
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    • 제37권5호
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    • pp.531-534
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    • 2010
  • Purpose: Lipobean$^{(R)}$s, widely used in lipodissolving techniques, contain phosphatidylcholine and sodium deoxycholate as its main substances. They have been approved only as medication for liver disease by the FDA. However, they have been used under various clinical settings without exact knowledge of its action mechanism. The authors designed an in vitro study to analyze the effects of different concentrations of phosphatidylcholine and sodium deoxycholate on adipocytes and other types of cells. Methods: Human adipose-derived stem cell were cultured and induced to differentiate into adipocytes. Fibroblasts extracted from human inferior turbinate tissue, and MC3T3-E1 osteoblast lines were cultured. Phosphatidylcholine solution dissolved with ethanol was applied to the culture medium at differing concentrations (1, 4, 7, 10 mg/mL). The sodium deoxycholate solution dissolved in DMSO applied to the medium at differing concentrations (0.07, 0.1. 0.4. 0.7 mg/mL). Cells were dispersed at a concentration of $5{\times}10^3$ cells/well in 24 well plates, and surviving cells were calculated 1 day after the application using a CCK-8 kit. Results: The number of surviving cells of adipocytes, fibroblasts and osteoblasts decreased as the concentration of sodium deoxycholate increased. However, all types of cells that had been processed in a phosphatidylcholine showed a cell survival rate of over 70% at all concentrations. Conclusion: This study shows that sodium deoxycholate is the more major factor in destroying adipocytes, and it is also toxic to the other cells. Therefore, we conclude that care must be taken when using Lipobean$^{(R)}$s as a method of reducing adipose tissue, for its toxicity may destroy other nontarget cells existing in the subcutaneous tissue layer.

효율적인 대역폭 이용과 정진폭 신호 전송을 위한 CACB-Q2PSK 변조 (CACB-Q2PSK Modulation for Efficient Bandwidth Utilization and Constant Amplitude Signal Transmission)

  • 홍대기
    • 한국산학기술학회논문지
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    • 제9권1호
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    • pp.93-99
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    • 2008
  • 본 논문에서는 정진폭 신호 특성을 갖는 기존의 정진폭 부호화된 다중 부호 이진 직교 (CACB: Constant Amplitude Coded Multicode Biorthogonal) 변조의 구조를 유지하면서 대역폭 효율을 증가시킴으로써 전송률을 높일 수 있는 방식을 제안한다. 높은 대역폭 효율을 얻기 위한 방식으로는 기존에 제안되었던 직교위상-직교위상 변조($Q^2$PSK: Quadrature-Quadrature Phase Shift Keying), 그리고 정진폭 직교위상-직교위상 변조 (CA-$Q^2$PSK: Constant Amplitude-$Q^2$PSK) 방식을 이용한다. 먼저 가장 간단한 결합 방식인 CACB-$Q^2$PSK 방식을 제안한다. 이 방식은 대역폭 효율은 증가하지만 정진폭 특성을 얻을 수는 없기 때문에 정진폭 특성을 유지하기 위한 새로운 첫 번째 CACB-CA-$Q^2$PSK (CACB-CA-$Q^2$PSK II) 변조 방식을 제안한다. 그러나 이 방식은 정진폭을 얻기 위해 여분의 부호화 과정이 필요하므로 대역폭 효율이 낭비되는 단점이 있다. 마지막으로 대역폭 효율을 감소시키지 않는 새로운 두 번째 CACB-CA-$Q^2$PSK (CACB-CA-$Q^2$PSK II) 변조 방식을 제안한다. 컴퓨터 모의실험을 통해 제안된 시스템의 성능을 평가함으로서 제안된 CACB-CA-$Q^2$PSK II 변조 방식의 효율성을 보이도록 한다.

In vitro 검출 시스템을 이용한 한약재 추출물들의 에스트로겐 유사활성 검증 (Verification of Estrogen Like Activities of Herbal Medicines Using an In Vitro Detection System)

  • 박성환;전명제;장민경;이솔지;김보경;전명정;김서연;김미향;이동근;이태호;남재섭;허지원;이상현
    • 동의생리병리학회지
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    • 제27권6호
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    • pp.752-758
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    • 2013
  • Estrogen like activities were evaluated using ethanol and hot water extracts of herbal medicines by using an in vitro detection system. Bokryung (Poria cocos), Sanyak (root of Dioscorea batatas) and Mokdanpi (root skin of Paeonia suffruticosa) represented statistically significant estrogen-like activities (p<0.001), while Omija (fruit of Schizandra chinensis), Taeksa (root of Alisma canaliculatum A. BR.), Jihwang (root of Rhemannia glutinosa), and Sansuyu (fruit of Cornus officinalis) did not. Estrogen-like activities of Bokryung hot water extract (500 ${\mu}g/ml$) and ethanol extract (50 ${\mu}g/ml$) were almost same as that of a C M $17{\beta}$-estradiol. Furthermore, estrogen-like activities of ethanol extracts (500 ${\mu}g/ml$) of Bokryung and Mokdanpi were stronger than that of $10^{-7}$ M $17{\beta}$-estradiol. These results suggest that Bokryung, Sanyak and Mokdanpi show estrogen-like activities. Especially, Sanyak and Mokdanpi represented promotive effect on the proliferation of MC3T3-E1 osteoblastic cells. Bokryung, Sanyak and Mokdanpi also exhibited superior inhibitory effect on the viability of RAW 264.7 cells. In conclusion, these three herbal medicines might be interpreted as candidates for the further study or development of functional foods or medicine to prevent or avoid postmenopausal symptoms of women.

Effect of Exogenous Fibrolytic Enzyme Application on the Microbial Attachment and Digestion of Barley Straw In vitro

  • Wang, Y.;Ramirez-Bribiesca, J.E.;Yanke, L.J.;Tsang, A.;McAllister, T.A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권1호
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    • pp.66-74
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    • 2012
  • The effects of exogenous fibrolytic enzymes (EFE; a mixture of two preparations from Trichoderma spp., with predominant xylanase and ${\beta}$-glucanase activities, respectively) on colonization and digestion of ground barley straw and alfalfa hay by Fibrobacter succinogenes S85 and Ruminococcus flavefaciens FD1 were studied in vitro. The two levels (28 and 280 ${\mu}g$/ml) of EFE tested and both bacteria were effective at digesting NDF of hay and straw. With both substrates, more NDF hydrolysis (p<0.01) was achieved with EFE alone at 280 than at 28 ${\mu}g$/ml. A synergistic effect (p<0.01) of F. succinogenes S85 and EFE on straw digestion was observed at 28 but not 280 ${\mu}g$/ml of EFE. Strain R. flavefaciens FD1 digested more (p<0.01) hay and straw with higher EFE than with lower or no EFE, but the effect was additive rather than synergistic. Included in the incubation medium, EFE showed potential to improve fibre digestion by cellulolytic ruminal bacteria. In a second batch culture experiment using mixed rumen microbes, DM disappearance (DMD), gas production and incorporation of $^{15}N$ into particle-associated microbial N ($^{15}N$-PAMN) were higher (p<0.001) with ammoniated (5% w/w; AS) than with native (S) ground barley straw. Application of EFE to the straws increased (p<0.001) DMD and gas production at 4 and 12 h, but not at 48 h of the incubation. EFE applied onto S increased (p<0.01) $^{15}N$-PAMN at 4 h only, but EFE on AS increased (p<0.001) $^{15}N$-PAMN at all time points. Prehydrolysis increased (p<0.01) DMD from both S and AS at 4 and 12 h, but reduced (p<0.01) $^{15}N$-PAMN in the early stage (4 h) of the incubation, as compared to non-prehydrolyzed samples. Application of EFE to barley straw increased rumen bacterial colonization of the substrate, but excessive hydrolytic action of EFE prior to incubation decreased it.

근적외선 분광분석법을 이용한 낙엽송 목분의 함수율 예측 모델 개발 (Development of Moisture Content Prediction Model for Larix kaempferi Sawdust Using Near Infrared Spectroscopy)

  • 장윤성;양상윤;정현우;강규영;최준원;최인규;여환명
    • Journal of the Korean Wood Science and Technology
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    • 제43권3호
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    • pp.304-310
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    • 2015
  • 저장 또는 운송단계에서 목분에 포함된 수분의 부적절한 조절은 생물학적 열화로 인한 품질하락 및 손실을 야기할 수 있기 때문에 목분의 함수율은 정확하게 측정되어야 하고 적절하게 조절되어야 한다. 본 연구에서는 근적외선(파장 대역: 1000-2400 nm) 분광분석법을 적용하여 낙엽송(Larix kaempferi) 목분의 함수율을 측정하고자 하였다. 각 상대습도($25^{\circ}C$, RH 30~99%) 단계별로 조습된 목분의 근적외선 반사스펙트럼을 측정하고, 적정 수학적 전처리(smoothing, standard normal variate)와 부분최소자승법을 적용하여 예측모델을 개발하였다. 도출된 함수율 예측모델은 높은 신뢰도를 보였다($R^2$ = 0.94, RMSEP = 1.544). 본 연구에서 개발된 근적외선 분광분석법을 통하여 비파괴적이면서 정확하고 신속한 목분 함수율의 측정과 효율적인 목재이용을 견인할 수 있으리라 기대된다.

도시 주차장내 수목그늘의 경제적 이익 연구 -미국 캘리포니아 데이비스 대학 주차장을 사례로- (A Study on the Economic Benefit of Urban Parking Lot Tree Shading -In the Case of University of California Davis Parking Lot-)

  • 장동수
    • 한국조경학회지
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    • 제33권6호
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    • pp.98-108
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    • 2006
  • The climate of urban area is an unstable type with considerable seasonal variation in precipitation wind speed, and temperature and it grows worse. Besides, ozone is a serious air pollutant in most of large cities. So worldwide, some of large cities are investing in forestry options to offset their climate problems, but lack of information has hindered comparisons of urban un cost effectiveness to other options. This research intends to study the economic benefits of tree shading of 19 parking lots in UCD campus. The economic benefits of tree shading are air conditioning savings, air quality, stormwater run-off, and other benefits. Especially, this study focuses how much the economic benefit of parking lot shading has been increased from 1995 to 2003 year by aerophoto. Some data on dimensions of parking lots and the number, size, tree species, and location of trees around each parking lot was inventoried. Two aerophotos(1995,2003) were used in order to analyze the increasement of tree canopy in 19 parking lots for 8 years. However, increasing coverage of trees and managing them for healthy growth would not be sufficient for avoiding adverse impacts by future climate change. Additional measures should be followed such as an increase of energy use efficiency and development of substitute energy. For example, coverage of trees help to save cooling energy by blocking solar radiation reaching parking cars and building structures through shading, and creating cool micro-climates through evapotranspiration. They also reduce heating demand by decreasing air infiltration and heat conduction out of the interior of buildings. Proper arrangement of vegetation over the parking lots can reduce cooling and heating costs. So proper planting design around hard space paving including species selection and location can significantly save cooling and heating energy. And a reduction in car and building's heating and cooling costs results in the reduction in energy demand which causes to emissions of air pollutants. Total increased tree canopy from 1995 to 2003 is $8,470.45m^2$ and the economic benefits is US$ 5,282.10. The economic benefit of one tree has been US$ 7.21 for 8 years. And an annually increased benefit is US$ 0.9 per a tree. If this kind of study is applied to studying the economic benefits of tree canopy in parking lots of Korea, it could result in guidelines of tree planting of parking lots. Because the trees selected for planting in parking lots were not suitable for an environment, the guidelines should contain a recommended list of trees. The guidelines should propose the shading percentage of parking lot when we plan a parking lot and contain the maintenance of trees in order to maximize the economic benefits of tree canopy.

Effects of Plant Extracts on Microbial Population, Methane Emission and Ruminal Fermentation Characteristics in In vitro

  • Kim, E.T.;Kim, C.H.;Min, K.S.;Lee, S.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권6호
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    • pp.806-811
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    • 2012
  • This study was conducted to evaluate effects of plant extracts on methanogenesis and rumen microbial diversity in in vitro. Plant extracts (Artemisia princeps var. Orientalis; Wormwood, Allium sativum for. Pekinense; Garlic, Allium cepa; Onion, Zingiber officinale; Ginger, Citrus unshiu; Mandarin orange, Lonicera japonica; Honeysuckle) were obtained from the Plant Extract Bank at Korea Research Institute of Bioscience and Biotechnology. The rumen fluid was collected before morning feeding from a fistulated Holstein cow fed timothy and commercial concentrate (TDN; 73.5%, crude protein; 19%, crude fat; 3%, crude fiber; 12%, crude ash; 10%, Ca; 0.8%, P; 1.2%) in the ratio of 3 to 2. The 30 ml of mixture, comprising McDougall buffer and rumen liquor in the ratio of 4 to 1, was dispensed anaerobically into serum bottles containing 0.3 g of timothy substrate and plant extracts (1% of total volume, respectively) filled with $O_2$-free $N_2$ gas and capped with a rubber stopper. The serum bottles were held in a shaking incubator at $39^{\circ}C$ for 24 h. Total gas production in all plant extracts was higher (p<0.05) than that of the control, and total gas production of ginger extract was highest (p<0.05). The methane emission was highest (p<0.05) at control, but lowest (p<0.05) at garlic extract which was reduced to about 20% of methane emission (40.2 vs 32.5 ml/g DM). Other plant extracts also resulted in a decrease in methane emissions (wormwood; 8%, onion; 16%, ginger; 16.7%, mandarin orange; 12%, honeysuckle; 12.2%). Total VFAs concentration and pH were not influenced by the addition of plant extracts. Acetate to propionate ratios from garlic and ginger extracts addition samples were lower (p<0.05, 3.36 and 3.38 vs 3.53) than that of the control. Real-time PCR indicted that the ciliate-associated methanogen population in all added plant extracts decreased more than that of the control, while the fibrolytic bacteria population increased. In particular, the F. succinogens community in added wormwood, garlic, mandarin orange and honeysuckle extracts increased more than that of the others. The addition of onion extract increased R. albus diversity, while other extracts did not influence the R. albus community. The R. flavefaciens population in added wormwood and garlic extracts decreased, while other extracts increased its abundance compared to the control. In conclusion, the results indicated that the plant extracts used in the experiment could be promising feed additives to decrease methane gas emission from ruminant animals while improving ruminal fermentation.

임플랜트에 연결한 영구자석이 임플랜트 주위 뼈모세포의 분포와 부착에 미치는 영향에 관한 연구 (THE EFFECT OF PERMANENT MAGNET CONNECTING WITH DENTAL IMPLANT ON DISTRIBUTION AND ATTACHMENT OF OSTEOBLAST-LIKE CELL AROUND THE DENTAL IMPLANT)

  • 오나희;최부병;권긍록;백진;이성복
    • 대한치과보철학회지
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    • 제43권4호
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    • pp.511-518
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    • 2005
  • Purpose: The purpose of this study is to find the effect of rare earth magnet's magnetic field of to the osteoblast around the implant by the means of observation number, and distribution around the implant which is connected to the permanent magnet but not, counted and compared by the number of cells attached to the surface of the implant. Material and method: The permanent magnets, made in the healing cap form, were connected to the implant future, and placed on the culture plate, The osteoblast-like cell: MC3T3-E1 were used for cell culture. As the control group, the implant were connected to normal healing cap, and cultured in the same conditions. 48 hours later, using inverted microscope, the number and distribution of osteoblast around the implant were observed, and 72 hours later, the number of the cells attached to the implant were counted. Results: As a result, the implant connected to the permanent magnet had proved to have a more concentrated cell distribution rate than the control group. The implant connected to the permanent magnet, neck area : which has about 10 gauss magnetic force, had more cells than apex area. The implant connected to the permanent magnet had proven to attach to the osteoblast more productively than control group's implant. Conclusions: This research showed that the magnetic field of the permanent magnet affected the distribution and growth rate of the osteoblast around the implant. In order to support this study, it also had need to monitor the progress of the permanent magnet specifically shown on the neck area, which has10 gauss magnetic force. So after additional research on the distribution and attachment of the cells, and further more, on bone formation, it will be concluded that the clinical applications ,such as immediate loading of implant treatment are possible.

식염용액에서 휴지(休止) 미생물 세포의 사멸 (Death of Non-growing Microbial Cells in Saline)

  • 강영미;경규항;박세원;유양자;김연순
    • 한국식품과학회지
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    • 제30권3호
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    • pp.660-664
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    • 1998
  • 식염용액에서 휴지미생물(non-growing microorganisms)의 사멸현상과 식염용액에서 미생물의 보호작용이 있다고 알려진 물질의 작용을 시험하였다. L. mesenteroides LA10, S. aureus B3l와 E. coli B34를 완충용액으로 제조한 0, 10, 20, 30%의 식염용액에서 배양하였을 때 각각 pH 6, 7, 5 부근에서 가장 높은 생존율을 나타내었고, 이 pH로부터 산성 또는 염기성쪽으로 변화시키거나 식염농도가 증가할 수록 생존율이 감소하였다. 젖산균 5종과 일반세균 9종 및 효모 2종의 균주를 pH 5, 6, 7로 조절한 10% 식염용액에서 실험해 본 결과 식염에 내성이 강한 pH는 미생물마다 달라 이는 균주의 특성에 속하는 것으로 사료되며 그람양성균이 그람음성균에 비해 식염내성이 높았으며 그람양성균 중에서도 젖산균이 식염에 대한 내성이 두드러지게 컸고 일반세균에서는 S. aureus가 큰 것으로 나타났다. 식염농도의 영향은 물론 pH가 식염용액에서 미생물의 사멸에 큰 영향을 미치는 것으로 나타났다. 식염의 미생물 생육저해작용으로부터 미생물을 보호한다고 알려진 물질들의 보호작용은 관찰되지 않았다.

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