• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.43-50
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• 2001

The effects of cardiac ischemia-reperfusion and $\beta$-adrenergic stimulation on metabolic function and energetics were investigated in Lan gendorff-perfused spontaneously hypertensive rat (SHR) hearts. Sarcoplasmic reticulum {TEX}$Ca^{2+}${/TEX}-dependent ATPase and cardiac lactate dehydrogenase (LDH) are additionally studied. The perfusion medium (1.0 mM {TEX}$Ca^{2+}${/TEX}) contained 5 mM glucose(+5 U/L insulin) and 2 mM pyruvate as substrates. Global ischemia was induced by reducing perfusion pressure of 100 to 40 cm {TEX}$H_{2}${/TEX}O, followed by 20 min reperfusin. Isoproterenol (ISO, 1$\mu$M) was infused for 10 min. Coronary vascular resistance and myocardial oxygen consumption ({TEX}$MVO_{2}${/TEX}) of SHR were increased in parallel with enhanced venous lactate during ischemia and reperfusion compared to those of Sprague Dawley (SD) hearts. Although ischemia-induced increase in venous lactate and combined adenosine plus inosine was abolished, coronary vasodilation produced in SD during reperfusion. In SHR, depressed reactive hyperemia was associated with a fall in cardiac ATP and CrP/Pi ratio and a rise in intracellular lactate/Pyruvate ratio. On the other hand, ISO produced coronary functional hyperemia and an increase in {TEX}$MVO_{2}${/TEX}. However, these responses were less than those in SHR hearts. The ATPase activity of SHR was attenuated in free {TEX}$Ca^{2+}${/TEX} concentrations used under basal condition and with ISO compared to that of SD. Venous lactate output and cardiac LDH activity were augmented in SHR as influenced by ISO. These results demonstrate that coronary reactive and functional hyperemia was dpressed in SHR, which cold be explained by alterations in the cytosolic phosphorylation potential and the cytosolic redox state manipulated by LDH, and by abnormal free calcium handling.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.263-274
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• 1996

Titanium dioxide ($TiO_{2}$) film has been widely used as anti-reflection coating for solar cells but not as masking oxide for metallisation and diffusion of impurities. In this paper we have investigated the properties of $TiO_{2}$ for possible incorporation into solar cell processing sequence. Thus the use of a spray deposition system to form the $TiO_{2}$ film and the characterisation of this film to ascertain its suitability to solar cell processing. The spray-on $TiO_{2}$ film was found to be resistant to all the chemicals used in conjunction with solar cell processing. The high temperature anealing (in oxygen ambient) of the spray-on $TiO_{2}$ film resulted in an increased refractive index, which indicated the growth of an underlying thin film of $SiO_{2}$ film for the passivation of silicon surface which would reduce the recombination activities of the fabricated device. Most importantly, the successful incorporation of the $TiO{2}$ film will lead to the reduction of the many high temperature processing steps of solar cell to only one.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.374-374
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• 2010

본 연구는 Roll-to-Roll Sputtering 장비를 사용하여 제작된 Flexible ITO electrode 필름의 방사선 검출기로의 적용가능성을 알아보기 위해 기존의 Glass ITO electrode의 전기적 특성을 비교 평가하였다. 본 연구는 Flexible ITO electrode와 Glass ITO electrode을 하부전극으로 형성하고, 최근에 X-ray 변환체로 활발히 연구되고 있는 Powder 형태의 반도체물질인 HgI2 와 PbI2를 Binder와 일정한 비율로 혼합하여 3-Rolls-Miller를 사용하여 Powder를 일정한 미세크기로 만들고, 대면적 제작이 용이한 Screen-Printing method을 이용하여 시편을 제작하였다. 제작된 필름은 하부전극의 종류에 따른 X-ray 입사 후의 전기적신호의 차이를 측정하고, HgI2와 PbI2 중 Flexible ITO electrode와 더욱 효율적으로 반응하여 기존의 Glass ITO electrode를 대체할 수 있는 전극을 발견하여 진단용 의료영상의 왜곡 현상을 제거할 수 있는 Flexible 방사선 검출기의 제작의 초석을 제공하는 연구를 목적으로 한다. SEM(Scanning Electron Microscope) 통하여 반도체 물질의 결정구조와 크기를 알아보았고, 하부 전극의 종류에 따른 전기적 신호검출을 위해 제작된 필름의 암전류(Dark current) 와 민감도(Sensitivity)를 측정한 후, SNR (Signal -to- Noise)을 계산하여 평가하였다.

• Journal of Dental Rehabilitation and Applied Science
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• v.21 no.1
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• pp.59-67
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• 2005

The bond strength of denture base resin and resin teeth, is an important factor in the long term prognosis of dentures. The purpose of this study is to find an appropriate combination of commercial denture base resin and artificial resin teeth according to shear bond strength. In this study, the shear bond strength of various denture base resins (Vertex $RS^{(R)}$(Dentimax Ziest, Holland), $PERform^{(R)}$(Hedent GmbH., Germany), SR $IVOCAP^{(R)}$(Ivoclar AG, Schaan, Liechtenstein)) and resin teeth (SR Orthosit PE(Ivoclar AG, Schaan, Liechtenstein), $Trubyte^{(R)}$ $Biotone^{(R)}$(Dentsply, U.S.A.)) was evaluated. 1. In comparison of denture resin, the shear bond strength increased in the order of $IVOCAP^{(R)}$, $PERform^{(R)}$, Vertex $RS^{(R)}$. 2. In resin teeth, $Trubyte^{(R)}$ $Biotone^{(R)}$ showed higher strength, but there was no statistical difference between the groups. 3. According to loading direction, the lingual showed higher strength, but there was no statistical difference. 4. When using SR Orthosit PE, SR $IVOCAP^{(R)}$ showed significantly higher shear bond strength(p<0.05). 5. Fracture tendancy showed more cohesive fractures(59) than adhesive failures(13). $IVOCAP^{(R)}$ showed the most superior results statistically. $Trubyte^{(R)}Biotone^{(R)}$ showed the highest shear bond strength. When using the SR Orthosit PE, it is thought that $IVOCAP^{(R)}$ would present the most superior results.

• The Journal of Advanced Prosthodontics
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• v.9 no.6
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• pp.463-469
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• 2017

PURPOSE. To evaluate the fit of a three-unit metal framework of fixed dental prostheses made by subtractive and additive manufacturing. MATERIALS AND METHODS. One master model of metal was fabricated. Twenty silicone impressions were made on the master die, working die of 10 poured with Type 4 stone, and working die of 10 made of scannable stone. Ten three-unit wax frameworks were fabricated by wax-up from Type IV working die. Stereolithography files of 10 three-unit frameworks were obtained using a model scanner and three-dimensional design software on a scannable working die. The three-unit wax framework was fabricated using subtractive manufacturing (SM) by applying the prepared stereolithography file, and the resin framework was fabricated by additive manufacturing (AM); both used metal alloy castings for metal frameworks. Marginal and internal gap were measured using silicone replica technique and digital microscope. Measurement data were analyzed by Kruskal-Wallis H test and Mann-Whitney U-test (${\alpha}=.05$). RESULTS. The lowest and highest gaps between premolar and molar margins were in the SM group and the AM group, respectively. There was a statistically significant difference in the marginal gap among the 3 groups (P<.001). In the marginal area where pontic was present, the largest gap was $149.39{\pm}42.30{\mu}m$ in the AM group, and the lowest gap was $24.40{\pm}11.92{\mu}m$ in the SM group. CONCLUSION. Three-unit metal frameworks made by subtractive manufacturing are clinically applicable. However, additive manufacturing requires more research to be applied clinically.

• The Journal of Advanced Prosthodontics
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• v.10 no.4
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• pp.328-334
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• 2018

PURPOSE. To evaluate the reproducibility of scan-based abutments using a blue light model scanner. MATERIALS AND METHODS. A wax cast abutment die was fabricated, and a silicone impression was prepared using a silicone material. Nine study dies were constructed using the prepared duplicable silicone, and the first was used as a reference. These dies were classified into three groups and scanned using a blue light model scanner. The first three-dimensional (3D) data set was obtained by scanning eight dies separately in the first group. The second 3D data set was acquired when four dies were placed together in the scanner and scanned twice in the second group. Finally, the third 3D data set was obtained when eight dies were placed together in the scanner and scanned once. These data were then used to define the data value using third-dimension software. All the data were then analyzed using the non-parametric Kruskal-Wallis H test (${\alpha}=.05$) and the post-hoc Mann-Whitney U-test with Bonferroni's correction (${\alpha}=.017$). RESULTS. The means and standard deviations of the eight dies together were larger than those of the four dies together and of the individual die. Moreover, significant differences were observed among the three groups (P<.05). CONCLUSION. With larger numbers of abutments scanned together, the scan becomes more inaccurate and loses reproducibility. Therefore, scans of smaller numbers of abutments are recommended to ensure better results.

• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.164-174
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• 2014

본 연구는 양념 닭 가슴살의 양념 액에 귤 껍질 추출물(CPE, 2%), 양파 껍질 추출물(OPE, 2%), calcium lactate(2%), 난황 유래 phosvitin(0.1%)과 CPE, OPE 및 calcium lactate 복합처리를 첨가하였을 때 서로 다른 저장온도와 저장기간에 따른 항균 효과 및 품질 변화를 확인하고자 수행되었다. 모든 저장온도와 저장기간에서 CPE, OPE 및 복합 처리군의 총 호기성 세균 수는 대조구에 비해 유의적으로 낮게 확인되었으며, 가장 높은 미생물 생장 억제 효과가 있었던 처리군은 CPE 처리군이었다. 하지만, calcium lactate와 phosvitin 처리군의 미생물의 성장 억제 효과는 나타나지 않았다. pH의 경우, calcium lactate와 OPE 처리군은 모든 저장온도의 저장 0일차에서 대조구에 비해 유의적으로 낮은 값을 나타내었다. OPE 처리군은 모든 저장온도와 저장기간에서 다른 처리구들에 비해 유의적으로 높은 적색도를 나타내었고, CPE와 함께 저장온도에 따른 유의적 차이를 나타내지 않았다. 하지만 이러한 OPE 처리군은 풍미, 맛 및 종합적 기호도에서 다른 처리구들에 비해 유의적으로 낮은 값을 보였으며, calcium lactate와 phosvitin 처리군의 종합적 기호도는 대조구와 유의적 차이가 나타나지 않았다. 결론적으로, 양념 닭가슴살의 CPE, OPE 및 복합처리군에서 저장온도를 달리한 저장기간에 따른 미생물 억제 효과를 확인할 수 있었으나, 관능적 특성을 개선하는 방법의 개발이 필요하다고 판단된다.

• Food Science of Animal Resources
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• v.34 no.2
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• pp.221-229
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• 2014

Chicken breast meat was injected with calcium chloride alone and in combination with lactic acid (0.01% and 0.002%, respectively). The inhibitory effects of the treatments on microbial growth were determined in the injected chicken breast meat stored at $4^{\circ}C$ under aerobic packaging condition for 0, 3, and 7 d. Calcium chloride combined with 0.002% and 0.01% lactic acid reduced microbial counts by 0.14 and 1.08 Log CFU/g, respectively, however, calcium chloride alone was unable to inhibit microbial growth. Calcium chloride combined with 0.01% lactic acid was the most effective antimicrobial treatment and resulted in the highest initial redness value. Calcium chloride alone and combined with lactic acid suppressed changes in pH and the Hunter color values during storage. However, injection of calcium chloride and lactic acid had adverse effects on lipid oxidation and sensory characteristics. The higher TBARS values were observed in samples treated with calcium chloride and lactic acid when compared to control over the storage period. Addition of calcium chloride and lactic acid resulted in lower sensory scores for parameters tested, except odor and color, compared to control samples. Therefore, the formulation should be improved in order to overcome such defects prior to industrial application.

• The Journal of Advanced Prosthodontics
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• v.10 no.5
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• pp.347-353
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• 2018

PURPOSE. The purpose of this study was to evaluate the marginal discrepancy of heat-pressed ceramic veneers manufactured using a CAD/CAM system. MATERIALS AND METHODS. The ceramic veneers for the abutment of a maxillary left central incisor were designed using a CAD/CAM software program. Ten veneers using a microstereolithography apparatus (AM group), ten veneers using a five-axis milling machine (SM group), and ten veneers using a traditional free-hand wax technique (TW group) were prepared according to the respective manufacturing method. The ceramic veneers were also fabricated using a heat-press technique, and a silicone replica was used to measure their marginal discrepancy. The marginal discrepancies were measured using a digital microscope (${\times}160$ magnification). The data were analyzed using a nonparametric Kruskal-Wallis H test. Finally, post-hoc comparisons were conducted using Bonferroni-corrected Mann-Whitney U tests (${\alpha}=.05$). RESULTS. The $mean{\pm}SD$ of the total marginal discrepancy was $99.68{\pm}28.01{\mu}m$ for the AM group, $76.60{\pm}28.76{\mu}m$ for the SM group, and $83.08{\pm}39.74{\mu}m$ for the TW group. There were significant differences in the total marginal discrepancies of the ceramic veneers (P<.05). CONCLUSION. The SM group showed a better fit than the AM and TW groups. However, all values were within the clinical tolerance. Therefore, CAD/CAM manufacturing methods can replace the traditional free-hand wax technique.

• The Journal of Advanced Prosthodontics
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• v.12 no.5
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• pp.299-306
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• 2020

PURPOSE. The aim of this study was to evaluate the accuracy of six recently introduced intraoral scanners (IOSs) for single crown preparations isolated from the complete arch, and to determine the effect of scanning sequence on accuracy. MATERIALS AND METHODS. A complete arch with right and left canine preparations for single crowns was used as a study model. The reference dataset was obtained by scanning the complete arch using a highly accurate industrial scanner (ATOS Core 80, GOM GmbH). Six different IOSs (Trios, iTero, Planmeca Emerald, Cerec Omnicam, Primescan, and Virtuo Vivo) were used to scan the model ten times each. The scans performed with each IOS were divided into two groups, based on whether the scanning sequence started from the right or left quadrant (n=5). The accuracy of digital impression was evaluated using three-dimensional analyzing software (Geomagic Studio 12, 3D Systems). The Kruskal Wallis and Mann- Whitney U statistical tests for trueness analysis and the One-way ANOVA test for precision analysis were performed (α=.05). RESULTS. The trueness and precision values were the lowest with the Primescan (25 and 10 ㎛), followed by Trios (40.5 and 11 ㎛), Omnicam (41.5 ㎛ and 18 ㎛), Virtuo Vivo (52 and 37 ㎛), iTero (70 and 12 ㎛) and Emerald (73.5 and 60 ㎛). Regarding trueness, iTero showed more deviation when scanning started from the right (P=.009). CONCLUSION. The accuracy of digital impressions varied depending on the IOS and scanning sequence used. Primescan had the highest accuracy, while Emerald showed the most deviation in accuracy for single crown preparations.