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The nanoleakage patterns of experimental hydrophobic adhesives after load cycling (Load cycling에 따른 소수성 실험용 상아질 접착제의 nanoleakage 양상)

  • Sohn, Suh-Jin;Chang, Ju-Hae;Kang, Suk-Ho;Yoo, Hyun-Mi;Cho, Byeong-Hoon;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
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    • v.33 no.1
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    • pp.9-19
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    • 2008
  • The purpose of this study was: (1) to compare nanoleakage patterns of a conventional 3-step etch and rinse adhesive system and two experimental hydrophobic adhesive systems and (2) to investigate the change of the nanoleakage patterns after load cycling. Two kinds of hydrophobic experimental adhesives, ethanol containing adhesive (EA) and methanol containing adhesive (MA), were prepared. Thirty extracted human molars were embedded in resin blocks and occlusal thirds of the crowns were removed. The polished dentin surfaces were etched with a 35 % phosphoric acid etching gel and rinsed with water. Scotchbond Multi-Purpose (MP), EA and MA were used for bonding procedure. Z-250 composite resin was built-up on the adhesive-treated surfaces. Five teeth of each dentin adhesive group were subjected to mechanical load cycling. The teeth were sectioned into 2 mm thick slabs and then stained with 50 % ammoniacal silver nitrate. Ten specimens for each group were examined under scanning electron microscope in backscattering electron mode. All photographs were analyzed using image analysis software. Three regions of each specimen were used for evaluation of the silver uptake within the hybrid layer. The area of silver deposition was calculated and expressed in gray value. Data were statistically analyzed by two-way ANOVA and post-hoc testing of multiple comparisons was done with the Scheffe's test. Silver particles were observed in all the groups. However, silver particles were more sparsely distributed in the EA group and the MA group than in the MP group (p < .0001). There were no changes in nanoleakage patterns after load cycling.

Comparison of electric and manual toothbrushes on periodontal health in fixed orthodontic patients (고정식 교정환자에서 치주건강 유지에 대한 전동치솔의 효과)

  • Park, Seong-Joon;Lee, Ki-Heon;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
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    • v.35 no.4 s.111
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    • pp.286-294
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    • 2005
  • The purpose of this study was to evaluate the efficacy of an electric toothbrush, with a specially designed orthodontic brush head, compared to a manual toothbrush on the periodontal health of patients with fixed orthodontic appliances Forty patients were randomly divided into two groups. the electric and the manual toothbrush groups, 1 month after attachment of fixed orthodontic appliances. Periodontal status was measured using a plaque index, a gingival index. a bleeding index, a pocket depth and a relative attachment loss, at baseline and after 3 months. 6 months, 9 mouths. and 12 mouths. The Braun Oral-B Plak Control with Ortho OD 15-1 brush head was used as the electric toothbrush while the Butler G.U.M 124 was given as the manual toothbrush. In the manual toothbrush group, the giugival and bleeding indices showed no statistically significant differences, but the plaque index was significantly decreased (P<0.001) and pocket depth as well as relative attachment loss were significantly increased (p<0.01). In the electric toothbrush group. the bleeding index, pocket depth and relative attachment loss showed no statistically significant differences. but the plaque and gingival indices were significantly decreased (p<0.001). In the case of the plaque. giugival and bleeding indices, there were no statistically significant differences between the electric and the manual toothbrush groups. On the contrary, in the case of pocket depth and relative attachment loss, there were statistically significant differences between the electric and the manual toothbrush groups: an increase in the manual toothbrush groups unlike the electric toothbrush group which kept the same state (P<0.05) These findings suggest that an electric toothbrush is useful for orthodontic patients with fixed appliances.

Basic Study on the Development of Analytical Instrument for Liquid Pig Manure Component Using Near Infra-Red Spectroscopy (근적외선 분광법을 이용한 돈분뇨 액비 성분분석기 개발을 위한 기초 연구)

  • Choi, D.Y.;Kwag, J.H.;Park, C.H.;Jeong, K.H.;Kim, J.H.;Song, J.I.;Yoo, Y.H.;Chung, M.S.;Yang, C.B.
    • Journal of Animal Environmental Science
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    • v.13 no.2
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    • pp.113-120
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    • 2007
  • This study was conducted to measure Nitrogen(N), Phosphate($P_2O_5$), Potassium ($K_2O$), Organic matter(OM) and Moisture content of liquid pig manure by Near Infrared Spectroscopy(NIRS) and to develop an alternative and analytical instrument which are used for measurement of N, $P_2O_5$, $K_2O$, OM, and Moisture contents for liquid pig manure. The liquid pig manure sample's transmittance spectra were measured with a NIRS in the wavelength range of 400 to 2,500 nm. Multiple linear regression and partial least square regression were used for calibrations. The correlation coefficient(RSQ) and standard error of calibration(SEC) obtained for nitrogen were 0.9190 and 2.1649, respectively. The RSQ for phosphate, potassium, organic matter and moisture contents were 0.9749, 0.5046, 0.9883 and 0.9777, and the SEC were 0.5019, 1.9252, 0.1180 and 0.0789, respectively. These results are indications of the rapid determination of components of liquid pig manure through the NIR analysis. The simple analytical instrument for liquid pig manure consisted of a tungsten halogen lamp for light source, a sample holder, a quartz cell, a SM 301 spectrometer for spectrum analyzer, a power supply, an electronics, a computer and a software. Results showed that the simple analytical instrument that was developed can approximately predict the phosphate, organic matter and moisture content of the liquid pig manure when compared to the analysis taken by NIRS. The low predictability value of potassium however, needs further investigation. Generally, the experiment proved that the simple analytical instrument was reliable, feasible and practical for analyzing liquid pig manure.

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Effects of Administration of Pyritum on Activation of Osteoblast Cells in Human Body & on Tibia Bone Fracture in Mice (자연동(自然銅)의 투여가 인체의 뼈모세포 활성과 생쥐 정강이뼈 골절에 미치는 영향)

  • Hwang, Ji-Hye;Ahn, Ji-Hyun;Kim, Jin-Teck;Ahn, Sang-Hyun;Kim, Kyung-Ho;Cho, Hyun-Seok;Lee, Seung-Deok;Kim, Eun-Jung;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.26 no.2
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    • pp.159-170
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    • 2009
  • Backgrounds and Objectives: A fracture means a loss of continuity in the substance of bone. Bone differs from other musculoskeletal tissue due to its ability to repair and heal itself without leaving a scar. The cutter head has multinucleated osteoclast cells to resorb the dead bone. The tail, with its conical surface, is lined with osteoblast cells laying down new bone. The conjugation of fracture is a unique biological process regulated by a complex array of signaling molecules and proinflammatory cytokines. Pyritum, one of the important prescriptions in the oriental medicine, has been used for conjugation fracture. The purpose of this study is to evaluate the effects of administration of Pyritum on activation of osteoblast cells in human body & on tibia bone fracture in mice. Materials and Methods : Four weeks aged 30 female DBA mice were used for this study. They were divided three groups, normal group, control group(fracture elicitate mice: FE group) and experimental group(Pyritum administered mice group after fracture elicitation : PA group). Left tibia bones of mice in FE and PA groups were fractured by bone cutters. MG-63 cells in human body th Pyritum in the ratio of 1 mg/m${\ell}$, and the cells were further incubated for 24 hours. Activation of osteoblast was identified using osteopontin, FGF in vitro test. In vivo test, regeneration of fractured tibia through the morphological changes was observed, and also activation of inflammation through NF-${\kappa}$B p65, iNOS, COX-2, osteoblast through osteopontin, FGF and osteoblast's proliferation in each group was measured. Results and Conclusions : 1. In vitro test for activation of osteoblast cells in human body by Pyritum, osteopontin and FGF production were remarkably increased in Pyritum treated MG-63 cells. 2. In regeneration of fractured tibia by Pyritum, fractured area in external tibia morphology was decreased more in the PA group than that of the FE group. Osteogenesis in fractured area was increased more in the PA group than that of the FE group. Also, endochodrial ossification in central area of fracture and osteoid in lateral area of fracture were increased more in the PA group than those of the FE group. 3. In activation of inflammation by Pyritum administered, activation of NF-${\kappa}$B p65, increase of iNOS and COX-2 production were higher in the PA and the FE groups than those of the control group. Especially, the PA group showed higher activation and increase than those of the FE group. 4. In activation of osteoblast by Pyritum, increase of osteopontin, FGF and osteoblast's proliferation were higher in the PA and the FE groups than those of the control group. Especially, the PA group showed higher increase and proliferation than those of the FE group.

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Effect of Transportation Distance of Broilers on Meat Grades and PSE Incidence (육계 출하 시 수송 거리가 닭고기의 도체 등급 및 PSE육 출현에 미치는 영향)

  • Chae, H.S.;Yoo, Y.M.;Jeong, S.G.;Ham, J.S.;Ahn, C.N.;Kim, D.H.;Jang, A.
    • Korean Journal of Poultry Science
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    • v.36 no.1
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    • pp.9-14
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    • 2009
  • This study was conducted to evaluate the effect of three types of transportation distance (short: less than 40 km; intermediate: 70~80 km; long: 140~150 km) on quality of whole chicken and chicken meat cuts. In whole chicken, $1^+$ grade chicken incidence after transportation of short, intermediate, and long distance transportation was 61.3, 56.3, and 43.8%, respectively. Bruise was not shown in breast and thigh, while wings with bruise after short and long distance transportation were 16.7% and 27.3%, respectively. For chicken meat cuts, $1^+$ grade chicken breast incidence after short distance transportation was 14% higher than that after long distance transportation. Bruised chicken breast after short and long distance transportation were 10 and 12%. Pale, soft, and exudative (PSE) chicken breast incidence after long distance transportation was higher (18.3%) than that after short distance transportation (7.0%). Chicken thigh cuts with $1^+$ grade after short and long distance transportation were shown 91.2% and 88.3%, respectively. Also, chicken wing cuts showed similar result to chicken thigh cuts' and $1^+$ grade incidence of chicken wings after short distance transportation was 11% higher than that of after long distance transportation. These results suggest that shorter transportation distance from farm to slaughter house result in high grade whole chicken and chicken meat cuts.

Effect of Nitrogen Fertilization on Quality Characteristics of Rice Grain and Aroma-active Compounds of Cooked Rice (질소시비가 발의 품질 특성과 취반미의 향기 성분에 미치는 영향)

  • Je-Cheon Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.6
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    • pp.527-533
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    • 2003
  • This experiment was conducted in 2001 to investigate the effect of four nitrogen levels (0, 5.5, 11, 16.5kg/10a) on the yield and quality of vice especially with respect to eating quality. One early-maturing variety (Daejinbyeo) and two mid-late-maturing varieties (Ilpumbyeo and Chucheongbyeo) were used in this experiment. Rice yields of all varieties were increased by the higher rate of nitrogen application, mainly due to a larger number of panicles per m2. Head rice ratio was reduced significantly with an increased rate of nitrogen, while immature vice ratio was increased significantly. Increasing the nitrogen application rate, a considerable increase of protein content was found in all tested rice varieties. Palatability value of Daejinbyeo and Ilpumbyeo measured by rice taster was not affected by nitrogen application rate ranging from 0 to 11 kg/10a, but it was decreased significantly at the rate of 16.5kg/10a. In contrast, the palatability value of Chucheongbyeo was decreased significantly by increasing nitrogen application at the whole application rate. A positive correlation was found between nitrogen application rate and protein content (r=$0.88^{**}\textrm{-}0.96^{**}$), but head rice (r=$-0.84^{**}$~$-0.91^{**}$) and palatability value (r=$-0.72^{**}$~$-0.85^{**}$) showed a negative correlation with the nitrogen application rate. Regardless of the fact that eleven aroma-active volatile compounds were detected in cooked vice of Chucheongbyeo, it was concluded that the aroma-active volatile compounds of cooked rice was not affected by the different nitrogen application rate. The results of this study showed that the standard nitrogen fertilization rate of 11kg/10a could be appropriate considering both rice yield and palatability.

Autometallography for Zinc Detection in the Central Nervous System (중추신경계통내 분포하는 Zinc의 조직화학적 동정)

  • Jo, Seung-Mook;Gorm, Danscher;Kim, Sung-Jun;Park, Seung-Kook;Kang, Tae-Cheon;Won, Moo-Ho
    • Applied Microscopy
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    • v.30 no.4
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    • pp.347-355
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    • 2000
  • Zinc is one of the most abundant oligoelements in the living cell. It appears tightly bound to some metalloproteins and nucleic acids, loosely bound to some metallothioneins or even as free ion. Small amounts of zinc ions (in the nanomolar range) regulate a plentitude of enzymatic proteins, receptors and transcription factors, thus rolls need accurate homeostasis of zinc ions. Zinc is an essential catalytic or structural element of many proteins, and a signaling messenger that is released by neural activity at many central excitatory synapses. Growing evidences suggest that zinc may also be a key mediator and modulator of the neuronal death associated with transient global ischemia and sustained seizures, as well as perhaps other neurological disease stoles. Some neurons have developed mechanisms to accumulate zinc in specific membrane compartment ('vesicular zinc') which can be evidenced using histochemical techniques. Substances giving a bright colour or emitting fluorescence when in contact with divalent metal ions are currently used to detect them inside cells; their use leads to the so called 'direct' methods. The fixation and precipitation of metal ions as insoluble salt precipitates, their maintenance along the histological process and, finally, their demonstration after autometallographic development are essential steps for other methods, the so called 'indirect methods'. This study is a short report on the autometallograhical approaches for zinc detection in the central nervous system (CNS) by means of a modified selenium method.

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Bottom electrode optimization for the applications of ferroelectric memory device (강유전체 기억소자 응용을 위한 하부전극 최적화 연구)

  • Jung, S.M.;Choi, Y.S.;Lim, D.G.;Park, Y.;Song, J.T.;Yi, J.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.8 no.4
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    • pp.599-604
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    • 1998
  • We have investigated Pt and $RuO_2$ as a bottom electrode for ferroelectric capacitor applications. The bottom electrodes were prepared by using an RF magnetron sputtering method. Some of the investigated parameters were a substrate temperature, gas flow rate, RF power for the film growth, and post annealing effect. The substrate temperature strongly influenced the surface morphology and resistivity of the bottom electrodes as well as the film crystallographic structure. XRD results on Pt films showed a mixed phase of (111) and (200) peak for the substrate temperature ranged from RT to $200^{\circ}C$, and a preferred (111) orientation for $300^{\circ}C$. From the XRD and AFM results, we recommend the substrate temperature of $300^{\circ}C$ and RF power 80W for the Pt bottom electrode growth. With the variation of an oxygen partial pressure from 0 to 50%, we learned that only Ru metal was grown with 0~5% of $O_2$ gas, mixed phase of Ru and $RuO_2$ for $O_ 2$ partial pressure between 10~40%, and a pure $RuO_2$ phase with $O_2$ partial pressure of 50%. This result indicates that a double layer of $RuO_2/Ru$ can be grown in a process with the modulation of gas flow rate. Double layer structure is expected to reduce the fatigue problem while keeping a low electrical resistivity. As post anneal temperature was increased from RT to $700^{\circ}C$, the resistivity of Pt and $RuO_2$ was decreased linearly. This paper presents the optimized process conditions of the bottom electrodes for memory device applications.

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Effects of Dietary Astragalus membranaceus, Ginseng and Onion Complex on Growth Performance and Carcass Characteristics in Finishing Pigs (비육돈에 있어 황기, 인삼, 양파 혼합물의 급여가 성장 밑 도체 특성에 미치는 영향)

  • Hong, Jong-Wook;Kim, In-Ho;Kim, Ji-Hoon;Kwon, Oh-Suk;Lee, Sang-Hwan;Seo, Wan-Soo;Kim, Chul;Kim, Eul-Sang;Chung, Yun-Hwa
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.1
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    • pp.149-154
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    • 2002
  • Seventy two Duroc $\times$ Yorkshire $\times$ Landrace pigs (75.66$\pm$1.86 kg average initial body weight) were used in a 45 days growth assay to determine the effects of Astragalus membranaceus, ginseng and onion complex on growth performance and carcass characteristics of finishing pigs. Dietary treatments included 1) Control (basal diet), 2) AGO 0.25 (basal diet + 0.25% Astragalus membranaceus, ginseng and onion complex), 3) AGO 0.50 (basal diet+0.50% Astragalus membranaceus. ginseng and onion complex). For overall period, average daily weight gain increased as the concentration of Astragalus membranaceus, ginseng and onion complex in the diets was increased (linear effect, p<0.01). Gain/feed improved without significant difference (p>0.05) as the concentration of Astragalus membranaceus, ginseng and onion complex in the diets was increased. As adding level of Astragalus membranaceus, ginseng and onion complex increased in the diets, A grade appearances of carcass tended to increase (linear effect, p<0.01). The total and LDL+VLDL cholesterol concentrations in serum of pigs fed AGO 0.25 diet were lower than them of pigs fed Control and AGO 0.50 diets without significant difference (p>0.05). $L^{*}$-, $a^{*}$-, and $b^{*}$- value of M. longissimus dorsi muscle were not significantly different among the treatments (p>0.05). Total feed cost per kg of weight gain was lower in the AGO 0.50 treatment (813 won) than in the Control (830 won). The results obtained from this feeding trial suggest that the Astragalus membranaceus, ginseng and onion complex supplementation for finishing pigs had improved growth performance. However, carcass characteristic was not affected by supplemental Astragalus membranaceus, ginseng and onion complex.lex.x.

A Study on the Current Status of Calcium fortification in the Processed Foods in Korea (우리나라 가공식품의 칼슘강화 현황에 관한 조사 연구)

  • 김욱희;김을상;유인실
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.1
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    • pp.170-176
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    • 2002
  • The objective of this study was to investigate the current status of calcium fortification in processed foods for obtaining basic data on nutrition fortification policy and nutrition labeling, Surveyed samples were the products fortified wish calcium among processed products sold in department store and large mart in Seoul from Aug. 1998 to Aug. 1999. But supplementary health food or special nutritious food and weaning food and infant formula were excluded from them. We examined the kinds and numbers of added nutrients except calcium and the amounts of calcium per 100 g product and nutrient labeling of calcium-fortified foods. Surveyed products were 81 foods and they were grouped in grain products, milk and milk products, processed meat and fishes, ramyuns, retort pouch foods, fruit juice and drinks. and others. Calcium fortification was found in wide food groups, especially in snack foods and carbonated beverages. In relation to surveyed products, most of them were fortified with only calcium. The number of added nutrients in the product were relatively various in comparison with each food groups. In addition to calcium, the most frequently added nutrient was DHA, and were followed vitamin, mineral, oligosacchride, fiber, etc. This result showed that the kind(s) and the number(s) of nutrient added to product did not consider nutrition balance of calcium-fortified foods. Units of calcium content were decided by companies, therefore consumers confused labelled content with mouth dose of calcium and the comparison of the amounts added calcium among products was difficult. The amounts of calcium in products were from 16.4 to 1226 mg Per 100 and from 2.5 to 27.6% RDA (recommended daily allowance) per serving size. The amounts of calcium in many products were less than 10% RDA per serving size, whole appraisal about fortified content was needed. And for nutrient labeling on calcium, they used various term whether it is approved by law or not.