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Evaluation of the Usefulness of Virtual Reality Equipment for Relieving Patients' Anxiety during Whole-Body Bone Scan (전신 뼈 검사 환자의 불안감 해소를 위한 가상현실 장비의 유용성 평가)

  • Kim, Hae-Rin;Kim, Jung-Yul;Lee, Seung-Jae;Baek, Song-Ee;Kim, Jin-Gu;Kim, Ga-Yoon;Nam-Koong, Hyuk;Kang, Chun-Goo;Kim, Jae-Sam
    • The Korean Journal of Nuclear Medicine Technology
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    • v.26 no.1
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    • pp.27-32
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    • 2022
  • Purpose When performing a whole-body bone scan, many patients are experiencing psychological difficulties due to the close distance to the detector. Recently, in the medical field, there is a report that using virtual reality (VR) equipment can give pain relief to pediatric patients with weak concentration or patients receiving severe treatment through a distraction method. Therefore, in this paper, VR equipment was used to provide psychological stability to patients during nuclear medicine tests, and it is intended to evaluate whether it can be used in clinical practice. Materials and Methods As VR equipment, ALLIP Z6 VR (ALLIP, Korea) was used and the experiment was conducted after connecting to a mobile phone. The subjects were 30 patients who underwent whole-body bone examination from September 1, 2021 to September 30, 2021. After intravenous injection of 99mTc-HDP, 3 to 6 hours later, VR equipment was put on and whole body images were obtained. After the test, a survey was conducted, and a Likert scale of 5 points was used for psychological anxiety and satisfaction with VR equipment. Hypothesis verification and reliability of the survey were analyzed using SPSS Statistics 25 (IBM, Corp., Armonk, NY, USA). Results Anxiety about the existing whole-body bone test was 3.03±1.53, whereas that of anxiety after wearing VR equipment was 2.0±1.21, indicating that anxiety decreased to 34%. When regression analysis of the effect of the patient's concentration on VR equipment on anxiety about the test, the B value was 0.750 (P<0.01) and the t value was 6.181 (P<0.01). decreased and showed an influence of 75%. In addition, overall satisfaction with VR equipment was 3.76±1.28, and the intention to reuse was 66%. The Cronbach α value of the reliability coefficient of the questionnaire was 0.901. Conclusion When using VR equipment, patients' attention was dispersed, anxiety was reduced, and psychological stability was found. In the future, as VR equipment technology develops, it is thought that if the equipment can be miniaturized and the resolution of VR content images is increased, it can be used in various clinical settings if it provides more realistic stability to the patient.

Stereospecific Analysis of the Molecular Species of the Triacylglycerols Containing Conjugate Trienoic Acids by GLC-Mass Spectrometry in Combination with Deuteration and Pentafluorobenzyl Derivatization Techniques (중수소화(重水素化), Pentafluorobenzyl화(化)와 GLC-Mass Spectrometry에 의한 Conjugate Trienoic Acid함유(含有) Triacylglycerol 분자종(分子種)의 입체특이적 분석(分析))

  • Woo, Hyo-Kyeng;Kim, Seong-Jin;Joh, Yong-Goe
    • Journal of the Korean Applied Science and Technology
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    • v.18 no.3
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    • pp.214-232
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    • 2001
  • CTA ester bonds in TG molecules were not attacked by pancreatic lipase and lipases produced by microbes such as Candida cylindracea, Chromobacterium viscosum, Geotricum candidium, Pseudomonas fluorescens, Rhizophus delemar, R. arrhizus and Mucor miehei. An aliquot of total TG of all the seed oils and each TG fraction of the oils collected from HPLC runs were deuterated prior to partial hydrolysis with Grignard reagent, because CTA molecule was destroyed with treatment of Grignard reagent. Deuterated TG (dTG) was hydrolyzed partially to a mixture of deuterated diacylglycerols (dDG), which were subsequently reacted with (S)-(+)-1-(1-naphthyl)ethyl isocyanate to derivatize into dDG-NEUs. Purified dDG-NEUs were resolved into 1, 3-, 1, 2- and 2, 3-dDG-NEU on silica columns in tandem of HPLC using a solvent of 0.4% propan-1-o1 (containing 2% water)-hexane. An aliquot of each dDG-NEU fraction was hydrolyzed and (fatty acid-PFB ester). These derivatives showed a diagnostic carboxylate ion, $(M-1)^{-}$, as parent peak and a minor peak at m/z 196 $(PFB-CH_{3})^{-}$ on NICI mass spectra. In the mass spectra of the fatty acid-PFB esters of dTGs derived from the seed oils of T. kilirowii and M. charantia, peaks at m/z 285, 287, 289 and 317 were observed, which corresponded to $(M-1)^{-}$ of deuterized oleic acid ($d_{2}-C_{18:0}$), linoleic acid ($d_{4}-C_{18:0}$), punicic acid ($d_{6}-C_{18:0}$) and eicosamonoenoic acid ($d_{2}-C_{20:0}$), respectively. Fatty acid compositions of deuterized total TG of each oil measured by relative intensities of $(M-1)^-$ ion peaks were similar with those of intact TG of the oils by GLC. The composition of fatty acid-PFB esters of total dTG derived from the seed oils of T. kilirowii are as follows; $C_{16:0}$, 4.6 mole % (4.8 mole %, intact TG by GLC), $C_{18:0}$, 3.0 mole % (3.1 mole %), $d_{2}C_{18:0}$, 11.9 mole % (12.5 mole %, sum of $C_{18:1{\omega}9}$ and $C_{18:1{\omega}7}$), $d_{4}-C_{18:0}$, 39.3 mole % (38.9 mole %, sum of $C_{18:2{\omega}6}$ and its isomer), $d_{6}-C_{18:0}$, 41.1 mole % (40.5 mole %, sum of $C_{18:3\;9c,11t,13c}$, $C_{18:3\;9c,11t,13r}$ and $C_{18:3\;9t,11t,13c}$), $d_{2}-C_{20:0}$, 0.1 mole % (0.2 mole % of $C_{20:1{\omega}9}$). In total dTG derived from the seed oils of M. charantia, the fatty acid components are $C_{16:0}$, 1.5 mole % (1.8 mole %, intact TG by GLC), $C_{18:0}$, 12.0 mole % (12.3 mole %), $d_{2}-C_{18:0}$, 16.9 mole % (17.4 mole %, sum of $C_{18:1{\omega}9}$), $d_{4}-C_{18:0}$, 11.0 mole % (10.6 mole %, sum of $C_{18:2{\omega}6}$), $d_{6}-C_{18:0}$, 58.6 mole % (57.5 mole %, sum of $C_{18:3\;9c,11t,13t}$ and $C_{18:3\;9c,11t,13c}$). In the case of Aleurites fordii, $C_{16:0}$; 2.2 mole % (2.4 mole %, intact TG by GLC), $C_{18:0}$; 1.7 mole % (1.7 mole %), $d_{2}-C_{18:0}$; 5.5 mole % (5.4 mole %, sum of $C_{18:1{\omega}9}$), $d_{4}-C_{18:0}$ ; 8.3 mole % (8.5 mole %, sum of $C_{18:2{\omega}6}$), $d_{6}-C_{18:0}$; 82.0 mole % (81.2 mole %, sum of $C_{18:3\;9c,11t,13t}$ and $C_{18:3 9c,11t,13c})$. In the stereospecific analysis of fatty acid distribution in the TG species of the seed oils of T. kilirowii, $C_{18:3\;9c,11t,13r}$ and $C_{18:2{\omega}6}$ were mainly located at sn-2 and sn-3 position, while saturated acids were usually present at sn-1 position. And the major molecular species of $(C_{18:2{\omega}6})(C_{18:3\;9c,11t,13c})_{2}$ and $(C_{18:1{\omega}9})(C_{18:2{\omega}6})(C_{18:3\;9c,11t,13c})$ were predominantly composed of the stereoisomer of $sn-1-C_{18:2{\omega}6}$, $sn-2-C_{18:3\;9c,11t,13c}$, $sn-3-C_{18:3\;9c,11t,13c}$, and $sn-1-C_{18:1{\omega}9}$, $sn-2-C_{18:2{\omega}6}$, $sn-3-C_{18:3\;9c,11t,13c}$, respectively, and the minor TG species of $(C_{18:2{\omega}6})_{2}(C_{18:3\;9c,11t,13c})$ and $ (C_{16:0})(C_{18:3\;9c,11t,13c})_{2}$ mainly comprised the stereoisomer of $sn-1-C_{18:2{\omega}6}$, $sn-2-C_{18:2{\omega}6}$, $sn-3-C_{18:3\;9c,11t,13c}$ and $sn-1-C_{16:0}$, $sn-2-C_{18:3\;9c,11t,13c}$, $sn-3-C_{18:3\;9c,11t,13c}$. The TG of the seed oils of Momordica charantia showed that most of CTA, $C_{18:3\;9c,11t,13r}$, occurred at sn-3 position, and $C_{18:2{\omega}6}$ was concentrated at sn-1 and sn-2 compared to sn-3. Main TG species of $(C_{18:1{\omega}9})(C_{18:3\;9c,11t,13t})_{2}$ and $(C_{18:0})(C_{18:3\;9c,11t,13t})_{2}$ were consisted of the stereoisomer of $sn-1-C_{18:1{\omega}9}$, $sn-2-C_{18:3\;9c,11t,13t}$, $sn-3-C_{18:3\;9c,11t,13t}$ and $sn-1-C_{18:0}$, $sn-2-C_{18:3\;9c,11t,13t}$, $sn-3-C_{18:3\;9c,11t,13t}$, respectively, and minor TG species of $(C_{18:2{\omega}6})(C_{18:3\;9c,11t,13c})_{2}$ and $(C_{18:1{\omega}9})(C_{18:2{\omega}6})(C_{18:3\;9c,11t,13c})$ contained mostly $sn-1-C_{18:2{\omega6}$, $sn-2-C_{18:3\;9c,11t,13t}$, $sn-3-C_{18:3\;9c,11t,13t}$ and $sn-1-C_{18:1{\omega}9}$, $sn-2-C_{18:2{\omega}6}$, $sn-3-C_{18:3\;9c,11t,13t}$. The TG fraction of the seed oils of Aleurites fordii was mostly occupied with simple TG species of $(C_{18:3\;9c,11t,13t})_{3}$, along with minor species of $(C_{18:2{\omega}6})(C_{18:3\;9c,11t,13t})_{2}$, $(C_{18:1{\omega}9})(C_{18:3\;9c,11t,13t})_{2}$ and $(C_{16:0})(C_{18:3\;9c,11t,13t})$. The sterospecific species of $sn-1-C_{18:2{\omega}6}$, $sn-2-C_{18:3\;9c,11t,13t}$, sn-3-C_{18:3\;9c,11t,13t}$, $sn-1-C_{18:1{\omega}9}$, $sn-2-C_{18:3\;9c,11t,13t}$, $sn-3-C_{18:3\;9c,11t,13t}$ and $sn-1-C_{16;0}$, $sn-2-C_{18:3\;9c,11t,13t}$, $sn-3-C_{18:3\;9c,11t,13t}$ are the main stereoisomers for the species of $(C_{18:2{\omega}6})(C_{18:3\;9c,11t,13t})_2$, $(C_{18:1{\omega}9})(C_{18:3\;9c,11t,13t})_{2}$ and $(C_{16:0})(C_{18:3\;9c,11t,13t})$, respectively.

Variation in Growth Characteristics of Pinus densiflora S. et Z. at Eight Experimental Plantations of Korea (8개(個) 시험지(試驗紙)에서 소나무 산지별(山地別) 생장특성(生長特性) 변이(變異))

  • Kim, Kyu Sick;Han, Young Chang
    • Journal of Korean Society of Forest Science
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    • v.86 no.2
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    • pp.119-127
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    • 1997
  • Japanese red pines growing along the Taebaek mountains have been called "Kangsong" and considered to be superior in growth and wood quality. An attempt was made to determine whether their boundaries for planting may be expanded by testing their early growth at eight experimental plantations of the Republic of Korea. Seeds were collected from the six different natural populations including Uljin in Kyongbuk province. For the provenance test, they were planted in eight different regions including Taean in the spring of 1987. Experimental planting was a randomized complete block design with 3 replications. Height growth was measured at the ages of 2, 4, and 6 after planting, and the diameter at root collar at the age of 6 after planting. Significant variation in height growth was observed among the plantations. The height growth measured at the age of 6 after planting showed a positive correlation with the latitude of the test plantation, and the contents of phosphate, potassium and calcium in the soil. A negative correlation, however, was observed between the longitude of the test plantation and height growth. Ponghwa provenance appeared to be the best among the provenances in that the trees from the area grew 16% better in volume growth than the average of all the trees tested in the study, while the worst one was Kyongju from which trees grew 11% less than the average.

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Characterization of a PyrR-deficient Mutant of Bacillus subtilis by a Proteomic Approach (프로테옴 분석에 의한 Bacillus subtilis PyrR 돌연변이체의 특성)

  • Seul, Keyung-Jo;Cho, Hyun-Soo;Ghim, Sa-Youl
    • Microbiology and Biotechnology Letters
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    • v.39 no.1
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    • pp.9-19
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    • 2011
  • The Bacillus subtilis pyrimidine biosynthetic (pyr) operon encodes all of the enzymes for the de novo biosynthesis of Uridine monophosphate (UMP) and additional cistrones encoding a uracil permease and the regulatory protein PyrR. The PyrR is a bifunctional protein with pyr mRNA-binding regulatory funtion and uracil phosphoribosyltransferase activity. To study the global regulation by the pyrR deletion, the proteome comparison between Bacillus subtilis DB104 and Bacillus subtilis DB104 ${\Delta}$pyrR in the minimal medium without pyrimidines was employed. Proteome analysis of the cytosolic proteins from both strains by 2D-gel electrophoresis showed the variations in levels of protein expression. On the silver stained 2D-gel with an isoelectric point (pI) between 4 and 10, about 1,300 spots were detected and 172 spots showed quantitative variations in which 42 high quantitatively variant proteins were identified. The results showed that production of the pyrimidine biosynthetic enzymes (PyrAA, PyrAB, PyrB, PyrC, PyrD, and PyrF) were significantly increased in B. subtilis DB104 ${\Delta}$pyrR. Besides, proteins associated carbohydrate metabolism, elongation protein synthesis, metabolism of cofactors and vitamins, motility, tRNA synthetase, catalase, ATP-binding protein, and cell division protein FtsZ were overproduced in the PyrR-deficient mutant. Based on analytic results, the PyrR might be involved a number of other metabolisms or various phenomena in the bacterial cell besides the pyrimidine biosynthesis.

Preparation of Conjugated Linolenic Acid from Urea Fractionated Perilla Seed Oil Hydrolysate (우레아 분별된 들기름 가수 분해물을 이용한 Conjugated Linolenic Acid(CLnA)의 합성)

  • Lee, Kyung-Su;Shin, Jung-Ah;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.12
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    • pp.1734-1742
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    • 2011
  • Conjugated linolenic acid (CLnA) and conjugated linoleic acid (CLA) are positional geometric isomers with three and two double bonds, respectively. In this study, perilla seed oil containing 60% ${\alpha}$-linolenic acid (C18:3) and 30% linoleic acid (C18:2) was used as a reaction substrate. After the perilla seed oil was hydrolyzed, conjugated fatty acids were synthesized using different reaction parameters, such as reaction time and concentration of sodium hydroxide. As a result, CLnA, CLA, and other newly synthesized conjugated isomers were present at levels of 14.5%, 14%, and 42.2%, respectively, when the reaction was performed with 20% NaOH, at $180^{\circ}C$, and for 1 hr. The results of GC-MS and fourier transform infrared spectroscopy (FT-IR) showed that CLnA isomer of cis-9, trans-11, and trans-13 octadecatrienoate, CLA isomer of cis-9, trans-11, and trans-10, cis-12 octadecadienoate, and other conjugated isomers were produced. Using urea, ${\alpha}$-linolenic acid could be concentrated from perilla seed oil hydrolysate. After concentration by urea, the concentration of ${\alpha}$-linolenic acid reached about 70%. After alkaline-isomerization was performed on the urea fraction containing 70% ${\alpha}$-linolenic acid, the content of CLnA increased up to 16.6%.

Ichthyofauna and Fish Community Structure in the Hoecheon Stream and Some Adjacent Tributaries of the Nakdonggang River, Korea (회천 및 인접 소하천들의 어류상과 군집 구조)

  • Chae, Byung Soo;Kim, Sang Ki;Kang, Yeong Hoon;Heo, Nam Soo;Yoo, Dong Uk;Park, Jae Min;Ha, Heon Uk
    • Korean Journal of Ichthyology
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    • v.29 no.3
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    • pp.205-217
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    • 2017
  • Fauna of freshwater fish and community structure were investigated at 24 stations in the Hoecheon Stream and some adjacent tributaries of the Nakdonggang River, Korea from July 2016 to August 2017. During the period 42 species and 4 types belonging to 32 genera and 11 families were collected. In this collection fishes of Cyprinidae were 24 species and 4 types, most numerous possessing 59.1% of all. There were 16 Korean endemic species including Acheilognathus yamatsutae and Odontobutis platycephala, 3 endangered species such as Pseudobagrus brevicorpus and Koreocobitis naktongensis (rank I) and Culter brevicauda (rank II) and 2 exotic species such as Micropterus salmoides and Lepomis macrochirus. Fish species transferred from other native rivers were 4 species including Opsariichthys uncirostris amurensis, Hemiculter eigenmanni, Odontobutis interrupta and Tridentiger brevispinis. Dominant species was Zacco koreanus NS type (19.2%) and sub-dominant species was Z. platypus R type (16.1%). The structure of fish community in the Hoecheon Stream was very stable and diverse in having diversity 2.91, evenness 0.77, dominance 0.35 and species richness 4.67. Fish community was divided into 4 groups such as upper, middle, midlower and lower reach group based on similarity among surveyed stations.

3-Dimensional Performance Optimization Model of Snatch Weightlifting

  • Moon, Young-Jin;Darren, Stefanyshyn
    • Korean Journal of Applied Biomechanics
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    • v.25 no.2
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    • pp.157-165
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    • 2015
  • Object : The goals of this research were to make Performance Enhanced Model(PE) taken the largest performance index (PI) through artificial variation of principle components calculated by principle component analysis for trial data, and to verify the effect through comparing kinematic factors between trial data (Raw) and PE. Method : Ten subjects (5 men, 5 women) were recruited and 80% of their maximal record was considered. The PI is a regression equation. In order to develop PE, we extracted Principle components from trial position data (by Principle Components Analysis (PCA)). Before PCA, we made 17 position data to 3 row matrix according to components. We calculated 3 eigen value (principle components) through PCA. And except Y (medial-lateral direction) component (because motion of Y component is small), principle components of X (anterior-posterior direction) and Z (vertical direction) components were changed as following. Changed principle components = principle components + principle components ${\times}$ k. After changing the each principle component, we reconstructed position data using the changed principle components and calculated performance index (PI). A Paired t-test was used to compare Raw data and Performance Enhanced Model data. The level of statistical significance was set at $p{\leq}0.05$. Result : The PI was significantly increased about 12.9kg at PE ($101.92{\pm}6.25$) when compared to the Raw data ($91.29{\pm}7.10$). It means that performance can be increased by optimizing 3D positions. The difference of kinematic factors as follows : the movement distance of the bar from start to lock out was significantly larger (about 1cm) for PE, the width of anterior-posterior bar position in full phase was significantly wider (about 1.3cm) for PE and the horizontal displacement toward the weightlifter after beginning of descent from maximal height was significantly greater (about 0.4cm) for PE. Additionally, the minimum knee angle in the 2-pull phase was significantly smaller (approximately 2.7cm) for the PE compared to that of the Raw. PE was decided at proximal position from the Raw (origin point (0,0)) of PC variation). Conclusion : PI was decided at proximal position from the Raw (origin point (0,0)) of PC variation). This means that Performance Enhanced Model was decided by similar motion to the Raw without a great change. Therefore, weightlifters could be accept Performance Enhanced Model easily, comfortably and without large stress. The Performance Enhance Model can provide training direction for athletes to improve their weightlifting records.

만덕봉 일대의 자원식물상과 식생

  • 박완근
    • Korean Journal of Plant Resources
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    • v.10 no.1
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    • pp.64-85
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    • 1997
  • This study was to establish the floristic composition and vegetation of resources vascular plants of Mt. Mandukbong(1,035.3 m; $128^{\circ}$54'24'E, $37^{\circ}$36'53'N). This work were investigated during the period of 1996. Resources vascular plants were composed of 97 families, 298 genera, 406 species, 70 varieties and 8 formae, Totaling 484 taxa. Among the investigated resources plants. 15 taxa(2.6%) were Korean endemic species. The forest were comparatively well conservated by Pteridophyta calculation(Pte-Q), 1.1 Useful of resources plants were Edible source(46.7%), Pasture source(37.2%), Medicinal source(35.5%), Ornamental source(12.1%)and Timber source(5.9%) respectively. The forest vegetion was classified into 1 order, 1 alliances, 1 suballiances and 4 communities; Rhododendro - Quercetalia mongolicae Kim 1990 Lindero - Quercion mongolicae Kim 1990 A. Typical community B. Quercus variablilis - Quercus mongolica Community Callicarpo - Quercenion serratae Kim 1990 C. Carex humilis v. nana - Pinus densiflora Community D. Juglans mandshurica - Urtica angustifloia community

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Thermal Process Evaluation and Simulation in a Pilot Scale Kimchi Pasteurizer (Pilot Scale 김치순간살균장치(瞬間殺菌裝置)에서의 살균효과분석(殺菌效果分析) 및 Simulation)

  • Gil, Gwang-Hoon;Kim, Kong-Hwan;Chun, Jae-Kun
    • Applied Biological Chemistry
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    • v.27 no.2
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    • pp.55-63
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    • 1984
  • Lethal effect on Chinese radish Kimchi was investigated by using a pilot scale Kimchi pasteurizer. A simulation model was presented so as to predict the change in viable cell concentration of the Kimchi during pasteurization. D values of microorganisms in the Kimchi were found to be 2.21, 1.62, 0.73, 0.39 and 0.21min at 60, 64, 70, 75 and $80^{\circ}C$, correspondingly, and thereby z value was $19^{\circ}C$. One cycle time required was 0.99min at flow rate of 4 l/min. The ratio of lethality in preheating section to total lethality was 0.3 and the ratio of lethality in holding, precooling and cooling sections to total lethality was 0.7. The experimental data were in good agreement with the values simulated by two model equations to which linear and exponential temperature profiles were applied at $65^{\circ}C\;and\;70^{\circ}C$ in holding section.

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AN EXPERIMENTAL STUDY ON THE SHEAR BOND STRENGTHS OF COMPOSITE RESIN TO AIR-ABRADED ENAMEL AND DENTIN (표면처리방법에 따른 복합레진의 결합강도에 관한 실험적 연구)

  • Shin, Jae-Ho;Jang, Ki-Taeg;Hahn, Se-Hyun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.24 no.1
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    • pp.112-124
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    • 1997
  • According to extensive use of composite resin which have superior esthetic property, every effort on improving bonding strength between a tooth and composite resin has been continued. Acid etching technique is a method that micro-etches the tooth surface which provides bonding with composite resin possible. Recently, there were several reports that mechanical treatment obtained from air-abrasion can provide similar bonding strength with acid etching technique. So, this experimental study was designed to compare the shear bonding strength between using air-abrasion technique and using acid etching technique. Initially, bovine teeth were divided into enamel and dentin experimental groups. Respectively each group was categorized into three subgroups. One subgroup was acid etched with 35% phosphoric acid, then bonded with composite resin. The other subgroup was air-abraded with $50{\mu}m$ $Al_2O_3$ particles sprayed with 160psi air pressure using air abrasion unit(KCP-1000, A.D.T., U.SA), and composite resin was bonded. In another subgroup, composite resin was bonded after acid etching following air-abrasion. So, enamel experimental groups were made of E1 (acid etched only), E2(air-abraded only), E3(acid etched following air-abraded), and dentin experimental groups were made of D1(acid etched only), D2(air-abraded only), D3(acid etched following air-abraded). Each subgroup had 10 specimens. Dentin bonding system(Scotchbond Multi-purpose, 3M Co., U.S.A.) and composite resin(Z-100, 3M Co., U.S.A.) were applied on treated surface using 5mm diameter gelatin capsule as manufacturer's direction. After 1200 times thermocycling between $5^{\circ}C$ and $55^{\circ}C$, shear bond strength was measured in 5mm/min crosshead speed with Instron(Instron Co., U.S.A.), and also treated enamel and dentin were observed with SEM(JEOL Co., Japan). The following results were obtained: 1. In the enamel experimental groups, acid etched following air-abraded group had highest shear bond strength, but there was no significant difference compared to acid etched group. Air-abraded only group had lowest shear bond strength, and there was significant difference compared to the rest of groups. 2. In the dentin experimental groups, acid etched following air-abraded group had highest shear bond strength, but there was no significant difference compared to acid etched group. Air-abraded only group had lowest shear bond strength, and there was significant difference compared to the rest of groups. 3. In the SEM study, air-abraded enamel and dentin had irregular and rough surfaces.

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