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EFFECT OF SURFACE ROUGHNESS ON BOND STRENGTH IN TITANIUM-PORCELAIN SYSTEM (타이타늄의 표면거칠기가 도재의 결합강도에 미치는 영향)

  • Kim, Sang-Hun;Vang, Mong-Sook;Yang, Hong-So;Park, Sang-Won;Park, Ha-Ok;Lim, Hyun-Pil;Oh, Gye-Jeong
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.2
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    • pp.182-190
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    • 2007
  • Statement of problem: Titanium has many advantages of high biocompatibility, physical properties, low-weight, low price and radiolucency, but it is incompatible with conventional dental porcelain due to titanium's oxidative nature. Many previous studies have shown that they used the method of sandblast for surface treatment prior to porcelain application, the researches are processing about the method of acid etching or surface coating. Purpose: The purpose of this research is to study the effect on bond strength of surface roughness between titanium and porcelain with the same surface topography. Material and method: In this study, we evaluated the bond strength by using 3-point bending test based on ISO 9693 after classified 8 groups - group P : polished with #1200 grit SiC paper, group S10 : $1.0{\mu}m$ surface roughness with sandblasting, group S15 : $1.5{\mu}m$ surface roughness with sandblasting, group S20 : $2.0{\mu}m$ surface roughness with sandblasting, group S25 : $2.5{\mu}m$ surface roughness with sandblasting, group S30 : $3.0{\mu}m$ surface roughness with sandblasting, group S35 : $3.5{\mu}m$ surface roughness with sandblasting, group E : $1.0{\mu}m$ surface roughness with HCl etching. Results: Within the confines of our research, the following results can be deduced. 1. In the results of 3-point bending test, the bond strength of sandblasting group showed significant differences from one of polishing group, acid etching group(P<.05). 2. The bond strength of sandblasting groups did not show significant differences. 3. After surface treatments, the group treated with sandblasting showed irregular aspect formed many undercuts, in the SEM photographs. The bond strength of sandblasting group was higher than 25 MPa, the requirement of ISO 9693. Conclusion: In above results, bond strength of titanium and low-fusing porcelain is influenced more to surface aspect than surface roughness. And titanium has clinically acceptable bond strength below surface roughness of $3.5{\mu}m$.

THE EFFECT OF PHOTODYNAMIC THERAPY ON THE VIABILITY OF STREPTOCOCCUS MUTANS ISOLATED FROM ORAL CAVITY (광역동 치료가 구강 내에서 분리한 수종의 Streptococcus mutans의 생존력에 미치는 영향)

  • Jung, Ji-Sook;Park, Ho-Won;Lee, Ju-Hyun;Seo, Hyun-Woo;Lee, Si-Young
    • Journal of the korean academy of Pediatric Dentistry
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    • v.39 no.3
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    • pp.233-241
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    • 2012
  • Photodynamic therapy (PDT) is a technique that involves the activation of photosensitizer by light in the presence of tissue oxygen, resulting in the production of reactive radicals capable of inducing cell death. The aim of this study was to evaluate the effect of PDT on Streptococcus mutans in planktonic conditions, previously treated with different photosensitive concentrations of erythrosine, using halogen and LED curing unit as a light source. And we compared the effects of PDT on six strains of S. mutans isolated from oral cavity and reference strain. As a result, S. mutans was susceptible to the combination of hand held photopolymerizer (HHP) and erythrosine. The higher concentration of erythrosine in the presence of light irradiation induced greater effects in reduction of viability of S. mutans. Isolated S. mutans showed a significant reduction in bacterial counts of the groups submitted to PDT compared to the control groups. And they appeared to be similar or slightly lower antimicrobial effect compared with reference strain. However, the difference was not significant (p < 0.05). In conclusion, PDT using erythrosine as a photosensitizing agent and HHP as a light source could be an efficient option for diseases caused by S. mutans.

Temporal and Spatial Characteristics of Visual and Somatosensory Integration in Normal Adult Brain (정상성인의 시각 및 촉각 통합 작용 시 뇌신경세포의 전기생리적활동의 시간 및 공간적 특성: 예비실험)

  • Ju, Yu-Mi;Kim, Ji-Hyun
    • The Journal of Korean Academy of Sensory Integration
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    • v.8 no.1
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    • pp.41-49
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    • 2010
  • Objective : Multisensory integration (MSI) is the essential process to use diverse sensory information for cognitive task or execution of motor action. Especially, visual and somatosensory integration is critical for motor behavior and coordination. This study was designed to explain spatial and temporal characteristics of visual and somatosensory integration by neurophysiological research method that identifies the time course and brain location of the SI process. Methods : Electroencephalography (EEG) and event-related potential (ERP) is used in this study in order to observe neural activities when integrating visual and tactile input. We calculate the linear summation (SUM) of visual-related potentials (VEPs) and somatosensory-related potentials (SEPs), and compared the SUM with simultaneously presented visual-tactile ERPs(SIM) Results : There were significant differences between the SIM and SUM in later time epochs (about 200-300ms) at contralateral somatosensory areas (C4) and occipital cortices (O1&O2). The amplitude of the SIM was mathematically larger than the summed signals, implying that the integration made some extra neural activities. Conclusion : This study provides some empirical neural evidence of that multisensory integration is more powerful than just combing two unisensory inputs in the brain and ERP data reveals neural signature relating to multisensory integrative process. Since this study is preliminary pilot study, larger population and criteria are needed for level of the significance. Further study is recommended to consider issues including effect of internally-driven attention and laterality of interaction to make the evidence by this study solid.

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Effect of Broussonetia papyrifera L. silage on blood biochemical parameters, growth performance, meat amino acids and fatty acids compositions in beef cattle

  • Tao, Hui;Si, Bingwen;Xu, Wencai;Tu, Yan;Diao, Qiyu
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.5
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    • pp.732-741
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    • 2020
  • Objective: The study was conducted to investigate the effects of Broussonetia papyrifera L. (B. papyrifera) silage on growth performance, serum biochemical parameters, meat quality, and meat amino acids and fatty acids compositions in beef cattle. Methods: Sixty-four male Angus beef cattle were assigned to 4 groups with 4 pens in each group and 4 beef cattle in each pen, and fed with the total mixed ration supplemented with 0%, 5%, 10%, or 15% B. papyrifera silage for 100 days (control group, 5% group, 10% group and 15% group) separately. Results: Beef cattle had significantly higher final body weight (BW) in 15% group, higher average daily gain (ADG) and dry matter intake (DMI) in 5% group, 10% group and 15% group, and higher feed conversion ratio (FCR) in 10% group and 15% group. Significantly higher blood superoxide dismutase (SOD) concentration was noted in 15% group, higher blood total antioxidant capacity (TAC) in 10% group and 15% group, lower 8-hydroxydeoxyguanosine (8-OHdG) and malondialdehyde (MDA) in 15% group. Meat had lower pH in 15% group, higher Commission International DeI'Eclairage (CIE) L in 5% group, 10% group, and 15% group, and lower drip loss in 15% group. Greater concentration of meat polyunsaturated fatty acids (PUFA) was observed in 10% group and 15% group, and docosahexaenoic acid (DHA) in 15% group. Conclusion: Diet with 15% B. papyrifera silage could improve performance and increase final BW, ADG, DMI, and FCR, enhance the antioxidant functions by decreasing blood 8-OHdG and MDA and increasing blood SOD and TAC, improve the meat quality by lowing pH and drip loss and increasing CIE L, increase the meat PUFA and DHA concentration. Polyphenols and flavonoids might be the main components responsible for the antioxidant activity and anti-biohydrogenation in the B. papyrifera silage. And B. papyrifera silage could be used as a new feedstuff in beef cattle nutrition.

Quality Characteristics of Jeju Traditional Doenjang (제주 전통된장의 품질 특성)

  • Oh, Hyun-Jeong;Lim, Ja-Hun;Lee, Ju-Yeon;Jeon, Si-Bum;Kang, Hye-Young;Oh, You-Sung;Oh, Young-Ju;Lim, Sang-Bin
    • Culinary science and hospitality research
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    • v.15 no.2
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    • pp.298-308
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    • 2009
  • In order to establish the quality standard of Jeju traditional Doenjang(soybean paste), general components, free sugar, organic acid, fatty acids, amino acids, and isoflavones contents were analyzed. Moisture, crude ash, crude protein, crude lipid, acid value, pH, and salinity were 37.33~47.43%, 12.75~15.97%, 11.06~14.28%, 0.08~0.53%, 17.83~27.55 mg/g, 4.82~5.12, and 10.66~13.91% respectively. The content of amino type nitrogen was 301.06~573.89 mg%. The compositions of free sugar were glucose (0.81~10.22 mg/g), maltose(0.64~5.28 mg/g), sucrose(0.78~3.86 mg/g), and fructose(0.72~1.11 mg/g). The major organic acid was lactic acid (89.30~180.39 mg/g). Total free amino acids were from 13.89 to 15.51%, which makes no difference between the test samples. Among amino acids, glutamic acid was abundant (2.12~2.55%). The contents of isoflavones were 274.87~431.96 mg/kg, less than those of commercial soybean paste. In fatty acid composition of soybean paste, the most abundant fatty acid was found to be linoleic acid as 61.54~66.79% in Jeju traditional Doenjang. This results might be caused by the differences of brewed periods, microflora, processing methods and used soybean cultivars.

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Study on the Characteristics of Dalgi Mineral Water in Cheongsong (청송 달기약수의 수질특성에 관한 연구)

  • Lee, Sung-Ho
    • Journal of the Korean Chemical Society
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    • v.44 no.3
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    • pp.220-228
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    • 2000
  • This study deals with the water qualities of Dalgi mineral spring in Cheongsong district.Water samples which were taken from upper, middle and bottorn spring sites were tested for twenty eight important water quality items including minerals, essential and/or toxic trace elements, and the analytical items to affect the taste of mineral water, seasonally from May 1999 to February 2000 The results obtained wereas follows:Each spring site showed much difference in major items. Bottom spring water showed higher value of Mg and Na than others. Middle spring water showed the highest value in all of the items except Mg and Na. The concentration of Hardness, Fe and Mn in mineral water were over than the normal standard for drinking water, but these items are not specified for the mineral water. As, Cd, $Cr^{6+}$ and Hg were not found and Pb was found ln trace level. All of the items proved nearly constant during the four seasons except water temperature. The contribution of mineral water to the nutrition of human was calculated in order to investigate the health effect of drinking water on the bases of Required Daily Allowance,one liter of water drinking and the mineral concentration of the bottom spring. The percentage of consumable minerals of Ca, Mg, Na, K, Mn,Zn and Fe were 35.05,36.43,5.88∼10.63,0.19∼0.57,21.86∼43.72,0.65, and 95.l respectively. This means Dalgl mineral water is pIenty of iron mineral. The K and O indexes of mineraI water appeared to be good for healthy and delicious water.

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The Effects of Organic Manure and Chemical Fertilizer Application Levels on the Growth and Nutrient Concentrations of Yellow Poplar (Liriodendron tulipifera Lin.) Seedlings (유기질 및 화학비료 처리수준이 어린 백합나무 생장 및 양분농도에 미치는 영향)

  • Han, Si Ho;An, Ji Young;Choi, Hyung-Soon;Cho, Min Seok;Park, Byung Bae
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.5
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    • pp.37-48
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    • 2015
  • Soil nutrient management is important to maintain the constant productivity of seedling production in the nursery for successful forest restoration. This study investigated the effects of organic manure and chemical fertilizer application levels on the growth, soil properties, and nutrient concentrations of yellow poplar seedlings. One-year-old yellow poplar seedlings were treated with the combination of 3 level organic manures(0, 5 Mg/ha, 10 Mg/ha; mixture of poultry manure, cattle manure, swine manure, and sawdust) and 3 level nitrogen-phosphorus-potassium(NPK) chemical fertilizers(0, 1x(urea, $30g/m^2$; fused superphosphate, $70g/m^2$; potassium chloride, $15g/m^2$), 2x). Organic manure significantly increased the soil pH and the concentrations of nitrogen, available phosphorous, exchangeable potassium, calcium, and magnesium. In contrast, the NPK chemical fertilizer decreased the soil pH and exchangeable calcium concentration, did not affect the soil concentrations of nitrogen and magnesium, and increased the concentrations of available phosphorous and exchangeable potassium. Both organic manure and NPK chemical fertilizer treatments increased the seedling height, root collar diameter, and dry weight by 39% and 25%, respectively. The treatment with manure 5 Mg/ha and NPK 2x chemical fertilizer mostly increased seedling dry weight by 2.6 times more than that of the control. Compared to the effects of the fertilization treatments on the soil properties, the effects on nutrient concentrations in the leaves were relatively small. These findings indicate that organic manure that was derived from livestock byproducts and sawdust can be utilized with chemical fertilizer to improve seedling production as well as conserving soil quality.

Preservation of Noodles Adding the Wheat Flour Ferment Cultured by Lactobacillus acidophilus (Lactobacillus acidophilus를 배양한 밀가루 발효물이 면의 저장성에 미치는 영향)

  • Cha, Wook-Jin;Lee, Jeong-Hoon;Lee, Si-Kyung
    • Korean Journal of Food Science and Technology
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    • v.39 no.2
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    • pp.164-168
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    • 2007
  • The principal objective of this study was to determine the effects of wheat flour ferment cultured with Lactobacillus acidophilus, specifically with regard to the preservation of noodles. The results showed that the addition of ferment to wheat flour during noodle preparation reduced the pH of the noodles, and no significant difference was observed in the L and ${\Delta}E$ values of the noodles adding 5% ferment. Total bacterial levels were decreased in the wet noodles to which more than 10% ferment was added, by a factor of log $10^3$ as compared to the levels seen in the control during storage. Deterioration became apparent at 4 days of storage in regular wet noodles, but did not occur until 6 days in the wet noodles to which 5% ferment was added, and not until 8 days of storage in the noodles to which 10% ferment was added. Cooked noodles deteriorated at 8 days after the beginning of storage, but the addition of 5% and 10% ferment extended that time to 12 days and 14 days, respectively. It was concluded that flour ferment cultured with L. acidophilus exerts favorable preservation effects on noodles and breads.

Changes of Nutritive Value and Productivity According to Stockpiled Period in Mixed Orchardgrass-Tall Fescue Pasture of Jeju Region (제주지역 오차드그라스 및 톨 페스큐 혼파초지의 비축시기별 사초 생산성 및 사료가치 변화)

  • Chae, Hyun Seok;Kim, Nam Young;Woo, Jae Hoon;Back, Kwang Soo;Lee, Wang Shik;Kim, Si Hyun;Hwang, Kyung Jun;Park, Seol Hwa;Park, Nam Gun
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.35 no.2
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    • pp.93-98
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    • 2015
  • This study was conducted to investigate the effect of different stockpiled periods on the nutritive value and productivity of mixed orchardgrass tall-fescue pasture (MOTP). This experiment was conducted at Jeju (island), South Korea, from Sep. 2012 to Nov. 2012. The DM yield of the MOTP had the highest in treatment in late August (2,983 kg/ha). The DM yields of swards were increased significantly by shortening the stockpiled period. The CP of the MOTP was 16.5% to 18.16%, and there did not appear to be a consistent trend in accordance with the duration of the stockpiled periods. The NDF and TDN content of the MOTP increased with the delay of the stockpiled periods, but there is a significant difference between the short- and long-stockpile periods; however, the ADF content of the MOTP decreased with shortened stockpile periods, but again, there is a significant difference between the two periods. In addition, P, Ca, Mg, Na, and Zn of MOTP increased by delaying the stockpile period, but Mn and Cu of MOTP decreased. As shown in the results of this research, the yield of MOTP was not increased by the atrophy of the growth of MOTP due to high temperatures in case where the MOTP was stockpiled from the beginning of August. The stockpile period of MOTP should therefore be started at the end of August to yield a stockpile of MOTP in the autumn.

Evaluation of Efficacy of Bacteriophage CJø07 against Salmonella enteritidis Infection in the SPF Chicks (박테리오파아지 CJø07의 Salmonella enteritidis 감염에 대한 SPF 병아리에서의 효능 평가)

  • Lim, Tae-Hyun;Lee, Hyun-Jeong;Kim, Myeong-Seob;Kim, Byoung-Yoon;Yang, Si-Yong;Song, Chang-Seon
    • Korean Journal of Poultry Science
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    • v.37 no.3
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    • pp.283-287
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    • 2010
  • In the present study we report in vivo inhibitory potential of single strain of bacteriophage ($CJ{\phi}07$) in day-old SPF chicks experimentally infected with Salmonella enteritidis (SE). The bacteriophages prepared by feed additives and drinking water were given to chicks for 20 days starting prior 10 days before challenge with SE. Chicks were euthanized at 10 days after challenge for quantitative salmonella isolation from intestine and determination of environmental contamination level of salmonella. Bacteriophage therapy as additives in feed and drinking water resulted in significant inhibition of the SE replication in intestines of SPF chickens (P<0.05). In addition, environmental contamination by SE fecal shedding was decreased in bacteriophage-treated birds. Therefore, bacteriophage $CJ{\phi}07$ examined in this study may be a plausible alternative to antibiotics for the reduction of salmonella infection both in poultry.