• Title/Summary/Keyword: Bio material

Search Result 1,225, Processing Time 0.027 seconds

A COMPARATIVE STUDY OF THE RESISTANCE TO DISLODGEMENT OF FIXED PROSTHESES USING $BIO-PIN^{(R)}$ ($Bio-pin^{(R)}$을 이용한 고정성 보철물의 탈락저항강도의 비교연구)

  • Yi Jong-Won;Cho In-Ho;Lee Jong-Hyuk;Kim Seung-Ki
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.43 no.2
    • /
    • pp.176-190
    • /
    • 2005
  • Statement of problem. The current trend in prosthodontics is the adoption of a conservative approach to preparing dental prostheses by minimizing the amount of sound tooth structure removal during preparation. Purpose. The major disadvantage of the adhesion bridge is the inherently poor resistance to dislodgement that its use in areas subjected to high occlusal load is limited. The purpose of this study was to compare the dislodgement resistance of $Bio-pin^{(R)}$, conventional 3-unit and adhesion bridges. Material and methods. The experimental groups were classified as follows : Group I : 3-unit bridge cemented using $Super-Bond^{(R)}$ C&B Group II : Adhesion bridge cemented using $Super-Bond^{(R)}$ C&B Group III : $Bio-pin^{(R)}$ design adhesion bridge without incorporation of $Bio-pin^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Group IV-1 : $Bio-pin^{(R)}$ retained adhesion bridge incorporating a single $Bio-pin^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Group IV-2 : $Bio-pin^{(R)}$ retained adhesion bridge incorporating a single $Bio-pin^{(R)}$ (cemented using $Panavia^{(R)}$ F) Group V : $Bio-pin^{(R)}$ retained adhesion bridge incorporating two $Bio-pins^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Results. The results of this study were as follows : 1. Significant differences in dislodgement resistance of the restorations were found between Group I, Group II and Group III (p<0.05). No significant differences in dislodgement resistance of the restorations were observed between Group I Group IV-1 and Group V. However, there were significant differences in dislodgement resistance between Group II and the other groups (p<0.05). 2. No significant differences in dislodgement resistance of the restorations were observed between GroupIV-1 and GroupIV-2, both of which utilized a single $Bio-pin^{(R)}$. However, significant differences were observed when Group III was compared to either GroupIV-1 or Group V (p<0.05). 3. No significant differences in dislodgement resistance relative to the type of dental cements used were found. Conclusion. From the above results, it is concluded that the dislodgement resistance of $Bio-pin^{(R)}$ bridge restorations utilizing a single $Bio-pin^{(R)}$ is similar to that of a conventional 3-unit bridge. The results also suggest that $Bio-pin^{(R)}$ bridge restorations using a single $Bio-pin^{(R)}$ are a viable alternative to the conventional 3-unit bridge when minimal removal of sound tooth structure and fulfillment of both function and esthetic aspects are considered.

The Fermentation Analysis of Mungyeong Green Apple (문경 풋사과를 활용한 발효 연구)

  • Kwon, Soon Goo;Choi, Sun Mi;Woo, Ji Hee;Supeno, Destiani;Choi, Won Sik
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.19 no.4
    • /
    • pp.231-236
    • /
    • 2016
  • In this study, Green apple from Mungyeong area was used as material in the fermentation process. In apple fruit growing process, to produce a high quality apple fruit, some Green apple should be removed. Since the removed Green apple fruit is inedible, it doesn't have any economical value. To solve this problem, this paper proposed fermentation process to increase the economical value of raw apple as a fermentation product. This research conducted seven days, and the pH and brix value analysis was done every 12 hours during fermentation process. The experimental results show that the fermentation product under blender treatment is better than cutting treatment and without cutting treatment. Initial brix 25% is the best treatment for fermentation because produce fermentation product with a good taste and aroma than other treatment.

Inhibitory Effects of Acinetobacter sp. KTB3 on Infection of Tobacco mosaic virus in Tobacco Plants

  • Kim, Young-Sook;Hwang, Eui-ll;O, Jeong-Hun;Kim, Kab-Sig;Ryu, Myong-Hyun
    • The Plant Pathology Journal
    • /
    • v.20 no.4
    • /
    • pp.293-296
    • /
    • 2004
  • During the screening of antiviral substances having inhibitory effects on Tobacco mosaic virus (TMV) infection on tobacco plants, we found a bacterial isolate KTB3, and identified it as Acinetobacter sp. which strongly inhibited the infection of TMV When the culture filtrate from KTB3 was applied on the upper surface of the Xanthi-nc tobacco leaves at the same time, or 24 hours before TMV inoculation, almost complete inhibition was achieved. Likewise, 86% inhibition was achieved, when the culture filtrate was applied on the underside of the leaves. In field trials, transmission of TMV from diseased seedlings to healthy ones during transplanting work was reduced by 92%, when the culture filtrate was sprayed onto the tobacco seedlings, cv. NC82, 24 hours before transplanting. No toxic effect was observed on the tobacco plants. Antiviral substance from the culture filtrate was purified by ethanol precipitation, dialysis, DEAE-cellulose, and Sephadex G75 gel column chromatography. The partially purified active material which showed positive color reaction to sugar and protein inhibited TMV infection by 60% at 1 ${\mu}$g/ml.

Reduction of Variable Illumination Effect on Pixel Gray-levels of Machine Vision

  • Suh S. R.;Huang J. K.;Kim Y. T.;Yoo S. N.;Choi Y. S.;Sung J. H.
    • Agricultural and Biosystems Engineering
    • /
    • v.5 no.1
    • /
    • pp.5-9
    • /
    • 2004
  • This study was carried out to develop methods of reducing the effect of solar illumination on pixel gray-levels of machine vision for agricultural field use. Two kinds of monochrome CCD cameras with manual and auto-iris lenses were used to take pictures within a range of 15 to 120 klux of solar illumination. A camera having more precise automatic control functions gave much better result. Four kinds of indices using pixel gray-level of the $99\%$ white DRS (diffuse reflectance standard) as a reference were tried to compensate pixel gray-levels of an image for variable illumination. Coefficients of variation of the indices within a range of illumination were used as a criterion for comparison. The study concluded that an index of (A+B)/A, where A is gray-level of the $99\%$ DRS and B is gray-level of the tested material, gave the best consistency in the range of solar illumination.

  • PDF

TDS Removal using Bio-sorption with AGS and High Concentration Nitrogen Removal (AGS의 생물흡착을 이용한 TDS 제거 및 고농도 질소제거에 관한 연구)

  • Eom, Han Ki;Choi, Yoo Hyun;Joo, Hyun Jong
    • Journal of Korean Society on Water Environment
    • /
    • v.32 no.3
    • /
    • pp.303-309
    • /
    • 2016
  • This study aimed to assay the biological removal of TDS (total dissolved solids) from RO (reverse osmosis) rejected water. Following bio-sorption of TDS with AGS (aerobic granular sludge), the effects of TDS on biological nitrogen removal were examined. The bio-sorption of TDS after AGS treatment was confirmed by checking for TDS removal efficiency and surface analysis of microorganisms with SEM and EDS. Then, the effects of TDS on biological nitrogen removal and the denitrification efficiency were evaluated using the MBR reactor. According to the results, the bio-sorption of TDS with AGS was 0.1 mg TDS/mg AGS, and we confirmed that the microorganism surfaces had adsorbed the TDS. Biological nitrogen removal efficiency was measured at inhibiting denitrification at 4,000 mg/L of TDS-injected material. Based on this study, it is necessary to pretreat TDS-containing RO rejected water and to maintain TDS concentration lower than a specific value (≤4,000 mg/L), when considering biological nitrogen removal.

Manufacturing System of Centrifugal Cast Metal Bearing by Dehydrogenation (탈수소 열처리 공정에 의한 원심주조 메탈베어링의 제조 시스템)

  • Kim, Jeung-Hun;Kim, Chung-Gu;Byen, Jea-Young;Lee, Eun-Suk;Yang, Ji-Yung;Choi, Won-Sik
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.19 no.5
    • /
    • pp.111-117
    • /
    • 2020
  • Centrifugal casting is suitable for producing hollow-products using centrifugal force. Bush type metal bearings are the key parts that facilitate the rotational movement of various machinery. Metal bearings produced by conventional centrifugal casting machines show rotational imbalance. Therefore, after injecting a large amount of material, the product's precision is secured in the secondary processing. Rotational imbalance is caused by the force acting on the rotary disc plate. In order to minimize rotational imbalance, NASTRAN was used for the optimal design and structural analysis. It was concluded that the rotating plate of the conventional centrifugal casting machine should be prevented from tilting. For this purpose, the location & thickness of the stiffeners were obtained through the optimum design. In the conventional centrifugal casting machine, both ends of the product are lower in temperature than the center part, so internal stress occurs. This solves this problem by inserting a heating coil into the rotating plate.

Bio-film Composites Composed of Soy Protein Isolate and Silk Fiber: Effect of Concentration of Silk Fiber on Mechanical and Thermal Properties

  • Prabhakar, M.N.;Song, Jung Il
    • Composites Research
    • /
    • v.27 no.5
    • /
    • pp.196-200
    • /
    • 2014
  • A novel, simple and totally recyclable method has been developed for the synthesis of nontoxic, biocompatible and biodegradable bio-composite films from soy protein and silk protein. Bio films are defined as flexible films prepared from biological materials such as protein. These materials have potential application in medical and food as a packaging material. Their use depends on various parameters such as mechanical (strength and modulus), thermal, among others. In this study, prepare and characterization of bio films made from Soy Protein Isolate (SPI) (matrix) and Silk Fiber (SF) (reinforcement) through solution casting method by the addition of plasticizer and crosslinking agent. The obtained SPI and SPI/SF composites were subsequently subjected to evaluate their mechanical and thermal properties by using Universal Testing Machine and Thermal Gravimetric Analyzer respectively. The tensile testing showed significant improvements in strength with increasing amount of SF content and the % elongation at break of the composites of the SPI/SF was lower than that of the matrix. Though the interfacial bonding was moderate, the improvement in tensile strength and modulus was attributed to the higher tensile properties of the silk fiber.

Current perspectives of bio-ceramic technology in endodontics: calcium enriched mixture cement - review of its composition, properties and applications

  • Utneja, Shivani;Nawal, Ruchika Roongta;Talwar, Sangeeta;Verma, Mahesh
    • Restorative Dentistry and Endodontics
    • /
    • v.40 no.1
    • /
    • pp.1-13
    • /
    • 2015
  • Advancements in bio-ceramic technology has revolutionised endodontic material science by enhancing the treatment outcome for patients. This class of dental materials conciliates excellent biocompatibility with high osseoconductivity that render them ideal for endodontic care. Few recently introduced bio-ceramic materials have shown considerable clinical success over their early generations in terms of good handling characteristics. Calcium enriched mixture (CEM) cement, Endosequence sealer, and root repair materials, Biodentine and BioAggregate are the new classes of bio-ceramic materials. The aim of this literature review is to present investigations regarding properties and applications of CEM cement in endodontics. A review of the existing literature was performed by using electronic and hand searching methods for CEM cement from January 2006 to December 2013. CEM cement has a different chemical composition from that of mineral trioxide aggregate (MTA) but has similar clinical applications. It combines the biocompatibility of MTA with more efficient characteristics, such as significantly shorter setting time, good handling characteristics, no staining of tooth and effective seal against bacterial leakage.

The Effect of Pretest Speed on Probe Tack in SIS-based Hotmelt PSA and Water-borne Acrylic PSA (핫멜트 점착제 및 아크릴 점착제에 대한 접촉속도(pretest speed)가 택에 미치는 영향)

  • Lim, Dong-Hyuk;Kim, Sung-Eun;Kim, Birm-Jun;Do, Hyun-Sung;Kim, Hyun-Joong
    • Journal of Adhesion and Interface
    • /
    • v.4 no.4
    • /
    • pp.7-14
    • /
    • 2003
  • "Tack" is defined as "the property that enables an adhesive to form a bond with the surface of another material upon brief contact under light pressure". The tack depends on a number of experimental parameters. We can control various experimental factors (contact force, dwell time, pretest speed) using probe tack tester. We are here concerned with pretest speed of experimental factors using SIS-based hotmelt PSA and water-borne acrylic PSA.

  • PDF