• Title/Summary/Keyword: Material test

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THE EFFECTS OF NANO-SIZED HYDROXYAPATITE ON DEMINERALIZATION RESISTANCE AND BONDING STRENGTH IN LIGHT-CURED GLASS IONOMER DENTAL CEMENT (광중합형 글라스아이오노머 시멘트의 탈회 저항성과 결합 강도에 대한 나노미터 입자의 하이드록시아파타이트의 효과)

  • Kim, Ji-Hee;Lee, Yong-Keun;Kim, Seong-Oh;Song, Je-Seon;Choi, Byung-Jai;Choi, Hyung-Jun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.37 no.1
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    • pp.24-34
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    • 2010
  • The aim of this study was to evaluate the effect of incorporated nano HA on the demineralization resistance and bonding strength of LC GIC in comparison with micro HA. Fuji II LC GIC was used as the control group and a base material for experimental groups. Two experimental groups were prepared. One was prepared by adding 15% micro HA to LC GIC by weight ratio (Exp. 1), and the other was prepared by adding 15% nano HA instead (Exp. 2). According to the results, the following conclusions could be obtained. 1. Observing under the CLSM, the control group showed thicker enamel demineralization layer than in the experimental groups, and the Exp. 2 group showed the thinnest demineralization layer. 2. In SEM analysis, there was greater enamel demineralization in the control group. The Exp. 2 group was more resistant to demineralization compared to the Exp. 1 group. 3. The bonding strength was found to be in the increasing order of control, Exp. 1, and Exp. 2 group (p < 0.05). 4. Observing the fractured surfaces under SEM after the bonding strength test was performed, there were bone-like apatite particles formed in HA-added experimental groups, and a greater number of bone-like apatite particles were formed in the Exp. 2 group compared to the Exp. 1 group.

Effect of Cooking methods with Various Heating Apparatus on the Quality Characteristics of Beef (가열기구에 따른 조리방법이 소고기의 품질특성에 미치는 영향)

  • Jeon, Ki-Hong;Kwon, Ki-Hyun;Kim, Eun-Mi;Kim, Young-Boong;Sohn, Dong-In;Choi, Jin-Young
    • Culinary science and hospitality research
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    • v.19 no.5
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    • pp.196-205
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    • 2013
  • This study showed the chemico-physical characteristics and sensory evaluation of beef loin and ribs with various kinds of cooking apparatus and methods like pan heating, boiling, grilling, steaming, cooking heating, charcoal heating and double layer pan heating. Double layer pan filled with Phase Change Materials(PCM) heating was also tested. Heating time of beef loin and ribs by oven heating was the longest as 55.5 and 25.7 min. Cooking loss of beef loin and ribs were 40.49%, 27.98% each and showed biggest in charcoal heating(p<0.05). In the chemical analysis, grilling resulted in the highest protein contents of 29.3% in the loin and double layer pan heating had 28.6% in the ribs. In the loin, 20.3% of crude fat was the highest in the double layer pan heating, and 21.9% of crude fat of ribs in the PCM heating(p<0.05). In the test of shearing forces, double layer pan heating had the lowest result of $9.14kg/cm^2$ in the loin and $7.03kg/cm^2$ in the ribs. In the 9 point-scale sensory evaluation, PCM treatment showed the best result of 7.67 in the juiciness of loin and single layer pan heating and grilling treatment had the highest score of 7.00 in the ribs. Loin in the PCM heating had 7.11 and ribs in the grilling had 7.13, showing the best in overall acceptability. With this experiments, we could find the chemico-physical and sensory characteristics of beef loin and ribs were affected by various cooking methods.

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A Study on the Influence of Finishing and Polishing Methods on the Gap between Denture Base Resin and Soft Liner (의치의 마무리와 연마법이 의치상 레진과 연성 이장재 간의 공극에 미치는 영향에 관한 연구)

  • Jung, Seung-Hwan;Lee, Joon-Seok
    • Journal of Dental Rehabilitation and Applied Science
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    • v.24 no.4
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    • pp.325-335
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    • 2008
  • The junction between resilient denture liner and the denture base is difficult to finish and polish due to difference of the physical property of the materials. Gaps tend to be formed during finishing and polishing procedures. The purpose of this study was measuring the width of junctional gap between $Molloplast-B^{(R)}$ and denture base material after finishing and polishing procedure, and evaluating the effect of method and direction on gap width. $Molloplast-B^{(R)}$ was processed (according to the manufacturer's instruction) against Lucitone $199^{(R)}$ acrylic resin. 50 specimens were fabricated with a raised center section. All of specimens were examined and photographed with a stereoscopic microscope(x120), and the largest gap along the junction of $Molloplast-B^{(R)}$ and acrylic resin on each specimen was measured. One-way analysis of variance(ANOVA) and independent t-test at 95% confidence level were used to analyze the data and to compare groups. The results of this study were as follows. In comparison with finishing tools, the gap width was the largest in $Molloplast^{(R)}$-Cutter and the smallest in FSQ-cross cut bur. There was statistically significant difference between FSQ-cross cut bur and $Molloplast^{(R)}$-Cutter(p<0.05). There was no significant difference in gap width between the direction of polishing. The mean value of gap width was the smallest in case of no polishing, and the largest in case of polishing with pumice & tin oxide. There was statistically significant difference between pumice and pumice & tin oxide. From the results, it is concluded that the use of $Molloplast^{(R)}$-Cutter in clinic need serious consideration even though it has good cutting ability. Further careful study is needed for finishing and polishing methods for decreasing gap width in junction of two materials.

Improving Corsican pine somatic embryo maturation: comparison of somatic and zygotic embryo morphology and germination

  • Wtpsk, Senarath;Shaw, D.S.;Lee, Kui-Jae;Lee, Wang-Hyu
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2003.04a
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    • pp.61-62
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    • 2003
  • Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

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Cognitive-enhancing Effects of a Fermented Milk Product, LHFM on Scopolamine-induced Amnesia (발효유 산물인 LHFM의 인지기능 개선 효과)

  • Jeon, Yong-Jin;Kim, Jun-Hyeong;Lee, Myong-Jae;Jeon, Woo-Jin;Lee, Seung-Hun;Yeon, Seung-Woo;Kang, Jae-Hoon
    • Korean Journal of Food Science and Technology
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    • v.44 no.4
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    • pp.428-433
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    • 2012
  • Probiotics and their products, such as yogurt and cheese have been widely consumed in many countries with proven health benefits including anti-microbial activity and anti-diarrheal activity. LHFM (Lactobacillus helveticus - fermented milk) is a processed skim milk powder, fermented by a probiotics, L. helveticus IDCC3801. In the present study, we aimed to investigate the neuroprotective effects and the cognitive improvements of LHFM. LHFM itself did not show any cytotoxicity to the human neuroblastoma cell line, SH-SY5Y; however, it dose-dependently protected against glutamate-induced neuronal cell death. LHFM also attenuated scopolamine-induced memory deficit in Y-maze and Morris-water maze. In the analysis of hippocampus after a behavior test, LHFM significantly increased the acetylcholine level and also inhibited acetylcholine esterase activity. Therefore, the raised acetylcholine release partially contributes to the improvement of learning and memory by a treatment with LHFM. These results suggest that LHFM is an effective material for prevention or improvement of cognitive impairments caused by neuronal cell damage and central cholinergic dysfunction.

Preparation of Functional Healthy Drinks by Acanthopanax senticosus Extracts (가시오가피를 이용한 기능성 건강음료의 제조)

  • Sung, Mi-Sun;Jung, Hoe-Yune;Choi, Jun-Hyeok;Lee, Sung-Cheol;Choi, Bo-Hwa;Park, Sung Sun
    • Journal of Life Science
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    • v.24 no.9
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    • pp.959-966
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    • 2014
  • This study was carried out to develop a functional healthy drink using 60% ethanol of dried Acanthopanax senticosus stem extract (ASE). The preparation, physical activity, anti-oxidant activity, and sensory properties of ASE were investigated. The moisture, crude protein, crude lipid, and ash contents of dried ASE were $6.50{\pm}0.12%$, $5.89{\pm}0.16%$, $1.18{\pm}0.11%$, and $3.03{\pm}0.40%$ respectively. The 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was $87.42{\pm}1.63%$ at 1/10 folds diluted ASE. In total, 40 male ICR mice were divided into five groups including the control (PBS), positive control (Red ginseng 200 mg/kg/day), and ASE-treated groups at doses of 35, 70, and 140 mg/kg/day for five weeks, respectively. ASE was administrated orally one time per day for five weeks before treadmill exercises, and normal and positive controls were fed PBS and red ginseng extract. In the treadmill test, ASE-treated mice (140 mg/kg/day) could run 1.4 times longer than the control mice. Healthy drinks were prepared with the addition of ASE at levels of 0.97% or 0.49% (A, B, and C type). Among the healthy drinks, the B type (ASE, 0.97%) was revealed to have the highest level of taste and overall acceptability through a sensory evaluation. The brix and pH of the ASE health drink (B type) were 14.9 and 4.51, respectively. These results indicated that the dried stem of Acanthopanax senticosus could be used as a functional material in the health drink industry.

Validation of QF-PCR for Rapid Prenatal Diagnosis of Common Chromosomal Aneuploidies in Korea

  • Han, Sung-Hee;Ryu, Jae-Song;An, Jeong-Wook;Park, Ok-Kyoung;Yoon, Hye-Ryoung;Yang, Young-Ho;Lee, Kyoung-Ryul
    • Journal of Genetic Medicine
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    • v.7 no.1
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    • pp.59-66
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    • 2010
  • Purpose: Quantitative fluorescent polymerase chain reaction (QF-PCR) allows for the rapid prenatal diagnosis of common aneuploidies. The main advantages of this assay are its low cost, speed, and automation, allowing for large-scale application. However, despite these advantages, it is not a routine method for prenatal aneuploidy screening in Korea. Our objective in the present study was to validate the performance of QF-PCR using short tandem repeat (STR) markers in a Korean population as a means for rapid prenatal diagnosis. Material and Methods: A QF-PCR assay using an Elucigene kit (Gen-Probe, Abingdon, UK), containing 20 STR markers located on chromosomes 13, 18, 21, X and Y, was performed on 847 amniotic fluid (AF) samples for prenatal aneuploidy screening referred for prenatal aneuploidy screening from 2007 to 2009. The results were then compared to those obtained using conventional cytogenetic analysis. To evaluate the informativity of STR markers, the heterozygosity index of each marker was determined in all the samples. Results: Three autosomes (13, 18, and 21) and X and Y chromosome aneuploidies were detected in 19 cases (2.2%, 19/847) after QF-PCR analysis of the 847 AF samples. Their results are identical to those of conventional cytogenetic analysis, with 100% positive predictive value. However, after cytogenetic analysis, 7 cases (0.8%, 7/847) were found to have 5 balanced and 2 unbalanced chromosomal abnormalities that were not detected by QF-PCR. The STR markers had a slightly low heterozygosity index (average: 0.76) compared to those reported in Caucasians (average: 0.80). Submicroscopic duplication of D13S634 marker, which might be a unique finding in Koreans, was detected in 1.4% (12/847) of the samples in the present study. Conclusion: A QF-PCR assay for prenatal aneuploidy screening was validated in our institution and proved to be efficient and reliable. However, we suggest that each laboratory must perform an independent validation test for each STR marker in order to develop interpretation guidelines of the results and must integrate QF-PCR into the routine cytogenetic laboratory workflow.

Screening of High-Palatability Rice Resources and Assessment of Eating Quality Traits of Korean Landraces and Weedy Rice Germplasms (우리나라 재래벼와 잡초벼의 식미 특성 평가 및 고식미 우수자원 탐색)

  • Kim, Choon-Song;Park, Hyun-Su;Baek, Man-Kee;Jeong, Jong-Min;Kim, Suk-Man;Park, Seul-Gi;Suh, Jung-Pil;Lee, Keon-Mi;Lee, Chang-Min;Cho, Young-Chan
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.4
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    • pp.299-310
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    • 2019
  • The eating quality of rice is one of the main concerns of rice breeding programs in many countries, especially in japonica rice cultivation areas. To select new resources with high eating quality from Korean native japonica rice, we evaluated a total of 76 varieties, including 47 native rice resources (26 landraces + 21 weedy rice) of Korea. In this study, all eating quality traits varied widely among the native resources, and some of the native resources revealed a high evaluation score in the palatability, expected eating quality, and physicochemical traits among the tested whole-plant materials. From the results, we selected two landraces (Sangdo and Waebyeo) and three weedy rice varieties (Hoengseongaengmi3, Namjejuaengmi6, and Wandoaengmi6) as promising resources for improvement of rice eating quality. Specifically, Wandoaengmi6 presented potential as a key breeding material for improving the eating quality of Korean rice cultivars, having the best evaluation results in palatability score (PS 0.83) from the sensory test and glossiness value (GV 81.8) from the Toyo taste meter of cooked rice. Given the urgent need to overcome the constraint of the narrow genetic background of Korean japonica rice, the results could be a practical solution for exploring new opportunities for improving rice eating quality through the expansion of genetic resources.

A Determination of the Moisturizing Effect and Stability of a Cream Containing Lespedeza cuneata G. Don Extracts (비수리 추출물 함유 크림의 보습 효능 및 안정성 평가)

  • Lee, Hye Jin;Gu, Hyun A;Park, Soo Nam
    • Microbiology and Biotechnology Letters
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    • v.40 no.3
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    • pp.237-242
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    • 2012
  • In this study, the skin moisturing effect and stability of cream containing L. cuneata G. Don extract (ethyl acetate fraction) were evaluated. The skin hydrating effect of the cream containing extract was 1020% higher than the placebo cream, and the TWEL of the cream containing extracts was decreased to $7.7g/m^2h$ compared to the control ($10.2g/m^2$) and placebo cream ($8.9g/m^2$). The pH, viscosity, and absorbance were measured under the 4, 25, 37, $45^{\circ}C$ and the sun light during the 12 weeks. The pH change between cream containing extract and placebo cream did not show the significant difference under the 4, 25, 37, $45^{\circ}C$ except for the sun light. Both creams showed high decrease (about 59%) of viscosity at $45^{\circ}C$. However, there was no significant change under other conditions. The absorbance of the cream containing the extract and the placebo cream was decreased similarly at all conditions. This decrease in absorbance was relatively small compared to the decrease of absorbance of the extract in ethanol solution under the sun light (Fig. 7). In addition, any change in color or smell of the cream was not observed during the 12 weeks. Also physical changes as creaming and cohesion were not shown. These results indicate that the cream containing L. cuneata extract has the skin moisturizing effect and is relatively stable. Therefore, it is suggested that the ethyl acetate fraction of L. cuneata extract could be applicable to cosmetics as a new cosmetic material with its antioxidative and antibacterial activities reported previously.

The dose distribution and DVH change analysis wing to effect of the patient setup error (환자 SET-UP ERROR에 따른 선량분포와 DVH 변화 분석)

  • Kim KyoungTae;Ju SangGyu;Ahn JaeHong;Park YoungHwan
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.2
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    • pp.81-89
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    • 2004
  • Introduction : The setup error due to the patient and the staff from radiation treatment as the reason which is important the treatment record could be decided is a possibility of effect. The SET-UP ERROR of the patient analyzes the effect of dose distribution and DVH from radiation treatment of the patient. Material & Methode : This test uses human phantom and when C-T scan doing, It rotated the Left direction of the human phantom and it made SET-UP ERROR , Standard plan and 3mm, 5mm, 7mm, 10mm, 15mm, 20mm with to distinguish, it made the C-T scan error. With the result, The SET-UP ERROR got each C-T image Using RTP equipment It used the plan which is used generally from clinical - Box plan, 3Dimension plan( identical angle 5beam plan) Also, ( CTV+1cm margin, CTV+0.5cm margin, CTV+0.3,cm margin = PTV) it distinguished the standard plan and each set-up error plan and The plan used a dose distribution and the DVH and it analyzed Result : The Box4 the plan and 3Dimension plan which it bites it got similar an dose distribution and DVH in 3mm, 5mm From rotation error and Rectilinear movement( $0\%{\sim}2\%$ ). Rotation error and rectilinear error 7mm, 10mm, 15mm, 20mm appeared effect it will go mad to a enough change in treatment ( $2\%{\sim}^11\%$ ) Conclusion : The diminishes the effect of the SET-UP ERROR must reduce move with tension of the patient Also, we are important accessory development and the supply that it reducing of reproducibility and the move

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