• Title/Summary/Keyword: material control

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THE EFFECT OF TEMPERATURE CHANGES ON THE PHYSICAL PROPERTIES OF POSTERIOR COMPOSITE RESINS (구치부용 복합 레진 가열시 물리적 성질의 변화에 관한 실험적 연구)

  • Park, Yeon-Hong;Min, Byung-Soon;Choi, Ho-Young;Park, Sung-Jin
    • Restorative Dentistry and Endodontics
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    • v.14 no.1
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    • pp.41-56
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    • 1989
  • The purpose of this study was to examine the effect of temperature dependence of the behavior on the physical properties of posterior composite resins. Three light cure posterior composite resins (Heliomolar, Litefil-P, and P-50) and one chemical cure posterior composite resin (Bisfil-II) were used as experimental materials. Composite resin was placed in a cylindrical brass mold (2.5 mm high and 6.5 mm inside diameter) that was rested on a glass plate. Another flat glass was placed on top of the mold, and the plate was tightly clamped together. After the mold had been filled with the light cure composite material, the top surface was cured for 30 seconds with a light source. Chemical cure resin specimens were made in the same manner as above. Three hundreds and twenty composite resin specimens were constructed from the four composite materials. One hundred and sixty specimens of them were placed in a heater at $50^{\circ}C$, $75^{\circ}C$, $100^{\circ}C$, $125^{\circ}C$, $150^{\circ}C$, $175^{\circ}C$ and $200^{\circ}C$ for 5 minutes or 10 minutes respectively before compressive strengths were measured. Another one hundred and sixty specimens were tested for the diametral tensile strengths in the same way as above. They were randomly divided into eight groups according to the mode of heating methods as follows and stored in distilled water at $37^{\circ}C$ for 24 hours. Group $37^{\circ}C$ - specimens were stored at $37^{\circ}C$ in distilled water for 24 hours. Group $50^{\circ}C$ - specimens were heated at $50^{\circ}C$ after curing. Group $75^{\circ}C$ - specimens were heated at $75^{\circ}C$ after curing. Group $100^{\circ}C$ - specimens were heated at $100^{\circ}C$ after curing. Group $125^{\circ}C$ - specimens were heated at $125^{\circ}C$ after curing. Group $150^{\circ}C$ - specimens were heated at $150^{\circ}C$ after curing. Group $175^{\circ}C$ - specimens were heated at $175^{\circ}C$ after curing. Group $200^{\circ}C$ - specimens were heated at $200^{\circ}C$ after curing. Twenty specimens of each of four composite resins were respectively made by insertion of materials into same mold for examining the dimensional changes between before and after heating. The final eighty specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before testing the dimensional changes. Compressive and diametral tensile strengths were measured crosshead speed 1mm/minute and 500Kg in full scale with a mechanical testing machine (DLC 500 Type, Shimadzu Co., Japan). Dimensional changes were determined by measuring the diametral changes of eighty specimens with micrometer (Mitutoyo Co., Japan). Results were as follows: 1. Diametral tensile strengths of specimens in all groups were increased with time heated compared with control group except for that in group $50^{\circ}C$ and the maximum diametral tensile strength was appeared in the specimen of Litefil-P heated for 10 minutes at $100^{\circ}C$. In heliomolar and P-50, it could be seen in the specimen heated for 10 minutes at $150^{\circ}C$, but in Bisfil-II, it could be found in the specimen heated for 5 minutes at $150^{\circ}C$. 2. Compressive strengths of specimens in all groups was tended to be also increased with time heated but that in group $50^{\circ}C$ and the maximum compressive strengths were showed in the same specimens conditioned as the diametral tensile strengths of four composite materials tested. 3. In Heliomolar, Litefil-P, and Bisfil-II, it was decreased in diameters of resin specimens between before heating and increased in diameters of resin specimens after storing in distilled water, but it was not in P-50. 4. There is little difference in diametral tensile strengths, compressive strengths, and dimensional changes followed by heating the resin specimens for 5 minutes and 10 minutes, but there is no statistical significances.

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Development Process for Decreasing Bitterness of Doraji (Platycodon grandiflorum) (도라지 쓴맛 개선을 위한 공정개발 연구)

  • Chang, Yoon-Je;Kim, Eunmi;Choi, Yun-Sang;Jeon, Ki-Hong;Kim, Young-Boong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.10
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    • pp.1550-1557
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    • 2015
  • This study was conducted to evaluate the improvement effects of bitter taste of doraji (Platycodon grandiflorum) with different freezing temperature conditions ($-5^{\circ}C$, $-10^{\circ}C$, $-20^{\circ}C$, and $-70^{\circ}C$). After freezing for 4 h, frozen doraji was thawed and dehydrated. Doraji frozen at $-20^{\circ}C$ showed higher contents of crude fat, crude protein, crude ash, crude fiber, and nitrogen free extract. Moisture, crude saponin, and total polyphenol contents of doraji frozen at $-5^{\circ}C$ were higher than in other samples. Weight loss of doraji was significantly different as freezing temperature decreased and the process repeated. Doraji frozen at $-5^{\circ}C$ showed higher contents of saponin and phenol than the control. Hardness of doraji increased as freezing temperature decreased. According to the preference test, Doraji frozen at $-5^{\circ}C$ showed higher preference and less bitter taste intensity than other samples. These results mean that doraji frozen at $-5^{\circ}C$ with less bitter taste could be utilized widely as a food material.

Comparative Study of the Biological Activity Effects of Manjakani (Quercus infectoria Olivier) Extract using Water and 80% Ethanol (열수 및 80% 에탄올로 추출한 만자카니(Quercus infectoria Olivier)의 생리활성 비교연구)

  • Lee, Hea-Jin;Kim, Dong-Han;Lee, Eun-Jin;Lim, Mi-Hye
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.1
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    • pp.124-132
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    • 2020
  • The purpose of this study was to investigate the biological activities such as cytotoxicity and anti-inflammation using Manjakani (Quercus infectoria Olivier) extract. Manjakani was extracted from hot DW and 80% ethanol. Cell viability was assessed using MTT assay on RAW 264.7 cells. Also, anti-inflammatory activities were measured through changes in the levels of nitric oxide (NO), prostaglandin E2 (PGE2), leukotrien B4 (LTB4), pro-inflammatory cytokines (IL-1β, IL-6 and tumor necrosis factor (TNF)-α) and transcription factor on LPS-induced RAW264.7 cells. The results confirmed that significant cytotoxicity does not appear in the concentration range of 1, 5, and 10 ㎍/㎖ of both extracts of this study. The production of NO was slowed by approximately MDE 37.2% and MEE 43.7% at 10 ㎍/㎖ concentration. Also, level of PGE2 and LTB4 was decreased MDE 30.9%/MEE 43.7% and MDE 37.1%/MEE 43.7%. In the case of inflammatory cytokine was reduced to MDE 38.8%/MEE 50.8% for IL-1β, MDE 35.0%/MEE 44.2% for IL-6 and MDE 31.9%/MEE 36.6% for TNF-α at 10 ㎍/㎖ concentration. The mRNA expression of NF-κB, iNOS and COX-2 significantly decreased by MDE 44.0%/MEE 16.0%, MDE 44.0%/MEE 55.0% and MDE 45.0%/MEE 40.0%, respectively, following the 10 ㎍/mL sample treatment when compared to the control. Both extracts were effective in anti-inflammatory activity. In addition, both extracts showed efficient changes of production of NO, PGE2, LTB4, pro-inflammatory cytokines and transcription factor. But MEE was found to have a higher inhibitory effect than MDE. In other words, Manjakani was showed significant biological activities showing anti-inflammation without cytotoxicity. These results will be provided as fundamental data for further development of the new health food and therapeutics related to the results above.

The Anti-inflammatory Effect of Skipjack Tuna (Katsuwonus pelamis) Oil in LPS-induced RAW 264.7 Cells and Mouse Models (LPS 유도 RAW 264.7 세포와 마우스 모델에서 참치(Katsuwonus pelamis) 유의 항염증 효과)

  • Kang, Bo-Kyeong;Kim, Min-Ji;Kim, Koth-Bong-Woo-Ri;Ahn, Na-Kyung;Choi, Yeon-Uk;Bark, Si-Woo;Pak, Won-Min;Kim, Bo-Ram;Park, Ji-Hye;Bae, Nan-Young;Ahn, Dong-Hyun
    • Microbiology and Biotechnology Letters
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    • v.43 no.1
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    • pp.45-55
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    • 2015
  • This study was carried out to demonstrate the anti-inflammatory effect of tuna oil (TO) using LPS-induced inflammation responses and mouse models. First, nitric oxide (NO) and pro-inflammatory cytokines levels were suppressed up to 50% with increasing concentrations of TO without causing any cytotoxicity. Also, the expression of a variety of proteins, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and nuclear factor kappa B (NF-κB), was suppressed in a dosedependent manner by treatment with TO. Furthermore, TO also inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs), including c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38 protein kinase (p38). Moreover, in in vivo testing the formation of ear edema was reduced at the highest dose tested compared to that in the control, and a reduction of ear thickness and the number of mast cells was observed in histological analysis. In acute toxicity test, no mortalities occurred in mice administrated 5,000 mg/kg body weight of TO over a two-week observation period. Our results suggest that TO has a considerable anti-inflammatory property through the suppression of inflammatory mediator productions and that it could prove to be useful as a potential anti-inflammatory therapeutic material.

Development of New Mushroom Substrate of Pleurotus Ostreatus Using Foodwaste and Wormcast (남은 음식물과 지렁이 분변토를 이용한 느타리버섯의 대체 배지개발)

  • Park, Jang-Woo;Park, Ki-Byung;Lee, Eun Young
    • Journal of the Korea Organic Resources Recycling Association
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    • v.20 no.4
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    • pp.75-85
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    • 2012
  • This study was investigated to develop an alternative medium for the cultivation of oyster mushrooms. The cultivation characteristics for major cultivated varieties of oyster mushrooms were campared with the food waste medium. In addition, water control & a gap formation of food waste is being pointed out as a problem of the medium material. Therefore, certain amounts of earthworm casting were supplied to the food waste medium to overcome the water and compaction phenomenon. This study investigated the use of the total 6 cultivars of oyster mushrooms, the Suhan(PL.1), Chiak No. 5(PL.2), Chiak No. 7(PL.3), Samgu No. 5(PL.4), Samgu No. 8(PL.5), Jangan No. 5(PL.6). In terms of medium, the optimum growth of the mycelium of the oyster mushroom was observed in the beet pulp medium but in food waste, the mycelium's growth was observed as insufficient in the bulk of cultivars. The Jangan No. 5(PL.6) was superior to other cultivars relative to the mycelium's growth. The optimum concentration of earthworm casting added the foodwaste medium was 30%. When Jangan No. 5(PL.6) was incubated in the foodwaste meidum containing 30% earthworm casting, the early days to germination were long, almost double the amount of time than that of the beet pulp medium. However, it was found that the fruit body size was larger than that of the beet pulp by up to 20.5%, and the length of the fruit body was up to 6.2% longer than that of the beet plup. The total yields increased by 60.5%. The analysis results of the oyster mushroom's nutritional contents cultured using the food waste medium, shows that the protein, vitamin A and vitamin E increased 70.6%, 2.4%, 0.8% respectively, the fat decreased by 12.6% and the oleic acid increased in a very small amount compared to that of the beet pulp medium.

Fourteen-day Repeated-dose Oral Toxicity Study of the Ethanol Extracts Isolated from Oplopanax elatus in Sprague-Dawley Rat (흰쥐에서 땃두릅 에탈올 추출물의 14일 반복경구토여에 의한 독성시험)

  • Kwon, Hyuck-Se;Kim, Dae-Hwan;Shin, Hyun-Kyung;Yu, Chang-Yeon;Kim, Myong-Jo;Lim, Jung-Dae;Park, Jae-Kun;Kim, Jin-Kyung
    • Korean Journal of Food Science and Technology
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    • v.39 no.4
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    • pp.470-475
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    • 2007
  • Oplopanax elatus (O. elatus) is a tall deciduous shrub that has traditionally been used for σ eating a variety of ailments such as diabetes, coughling, rheumatism, gastro-intestinal disorders, and wounds. In order to examine the safety of the ethanol extracts of O. elatus, we performed a 14-day repeated-dose toxicity study with Sprague-Dawley rats. The rats were treated with daily doses of the D. elatus ethanol extracts by gavage at 0, 500, 1000, and 2000 mg/kg/day for 14 consecutive days. We recorded clinical signs of toxicity, body weight, hematology, organ weights, gross and histological changes in target organs, and clinical chemistry analysis data for all rats. There were no significant changes in body and organ weights during the experimental period. The hematological analysis and clinical blood chemistry data revealed no toxic effects from the O. elatus ethanol extracts. Pathologically, neither gross abnormalities nor histopathological changes were observed between the control and treated rats of both sexes. Collectively, these data suggest that the ethanol extracts of O. elatus have a high margin of safety.

Studies on the Desalinization and Improvement of Physical-chemical Characteristics of Saline and Alkali Soils by CHP Treatment (CHP에 의(依)한 간척지(干拓地) 토양(土壤)의 제염(除鹽) 및 이화학성질개량(理化學性質改良)에 관(關)한 시험연구(試驗硏究))

  • Lee, S.H.;Oh, J.S.;Im, C.N.
    • Applied Biological Chemistry
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    • v.8
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    • pp.65-73
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    • 1967
  • For the study of method for salt elimination aimed at reforming tidal land into normal paddy fields in a short period with reduction of periods requiring for elimination of saline, CHP (a kind of Ca-hum ate), a soil conditioner made of peat as a main material was tried. In the pot experiment, effect on elimination of salt, improvement of physical-chemical characteristics and rice cultivation test were studied. The results of these tests are as follows: 1, CHP treatment somewhat improves aggregation state with some effect on aggregation. 2. CHP treatment is remarkably effective in permeability which increases with 1.0 percent treatment by three times in percolation rate, and by 4.5 times in volume of leached water respectively. 3. With the increase of CHP amounts, salt was eliminated in short period. When 80% of the total Na was leached in 1.0% CHP-A treated pot, control pot begins permeable. 4. CEC and phosphorous absorption capacity are not influenced by CHP treatment. 5. Growing state of rice is greatly influenced by rainfalls. Growth of rice in tidal land however are almost similar to those in normal paddy fields with layer amounts of CHP treatment. With salt content in the soils, saline hazard and numbers of ineffective stems, amounts of unmatured grain are increased. 6. With the treatment of CHP yields of rough rice were increased. With 0.5% CHP treatment the yields were similar to those of the normal paddy fields. With 1.0% CHP-A treatment, the yields were increased by 15 times more than those of none treated soil and by 25 percent more than normal paddy soils.

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Soil Physical Properties and Organic Matter (토양(土壤)의 물리성(物理性)과 유기물(有機物))

  • Im, Jeong-Nam
    • Korean Journal of Soil Science and Fertilizer
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    • v.11 no.3
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    • pp.145-160
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    • 1979
  • The effects of organic material application on soil physical properties were reviewed in relation to soil productivity. The organic matter contents and soil physical properties of the cultivated land in Korea were summarized and the effects of organic matter were compared in terms of land uses and soil types. Soil physical properties related to crop yield potential, such as soil aggregation, permeability, water holding capacity, erodibility, and compactibility, were used in evaluating the effects of organic materials as a soil physical amendment. The benefical effects of organic matter addition on soil physical conditions include (1) better aeration and increased infiltration in silty and clayey soils, (2) increased water holding capacity and moisture availability in sandy soils, (3) decreased soil erodibility, and (4) increased resistance to compaction. It is, therefore, concluded that continuous application of organic materials could greatly improve the various soil physical properties and favor the growth and yield of crops. A high rate of organic matter addition could contribute to reducing not only the soil erosion on sloping land, but also the possible detrimental effect of farm mechanization. In general, the effects of organic matter on soil physical improvement were estimated to be much higher in upland than in paddy. Organic matter would have a more pronounced effect on low productive lands such as heavy clayey or sandy soils and newly reclaimed soil. The optimum level of soil organic matter content was estimated to be about 3.0 to 3.5% for the best soil physical condition. Since the organic matter contents of the cultivated lands in Korea are much lower than optimum level, it would be desiable to use more organic materials to soil for the increase of soil productivity, continuation of stabilized high productivity and soil erosion control.

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The Cell Cycle Dependence and Radiation-induced Apoptosis in SCK Mammary Adenocarcinoma Cell Line (SCK선암 세포주에서 방사선에 의한 Apoptosis와 세포 주기)

  • Lee Hyung Sik;Park Hong Kyu;Hur Won Joo;Seo Su Yeong;Lee Sang Hwa;Jung Min Ho;Park Heon Joo;Song Chang Won
    • Radiation Oncology Journal
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    • v.16 no.2
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    • pp.91-98
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    • 1998
  • Purpose : The relationship between environmental PH on the radiation induced-apoptosis in SCK mammary adenocarcinoma cells and cell cycle dependence was investigated. Material and Methods : Mammary adenocarcinoma cells of A/J mice(SCK cells) in exponential growth phase were irradiated with a $l37^Cs$ irradiator at room temperature. The cells were irradiated 1 hour after the media was replaced with fresh media at a different pHs. After incubation at $37^{\circ}C$ for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Bssults : The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. When the cells were irradiated and maintained in pH 7.5 medium, the percentage of cells in $G_2/M$ phase rapidly increased to about $70\%$ at 12 h after an exposure to 120y and returned to control level by 36 h. The percentage of cells in G1 phase decreased as the percentage of cells in $G_2/M$ increased. On the other hand, in pH 6.6 medium the percentage of cells in G2/M phases gradually increased to about $45\%$ at 24 h after 12Gy irradiation and then slowly recessed and consequently, as much as $30-35\%$ of the cells were still in the Ga/M phase 48 h after irradiation. The percentage of cells in G1 phase then increased as the Ga/M arrest began to recede. The radiation-induced Ga/M arrest in PH 0.0 medium lasted markedly longer than that in pH 7.5 medium. Conclusion : Radiation-induced apoptosis in SCK tumor cells are reversely suppressed in an acidic environment. Radiation-induced Ga/M arrest is prolonged in an acidic environment indicating that the suppression of radiation-induced apoptosis and prolongation of radiation-induced Ga/M arrest in an acidic environment are related.

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The Effects of Packed Red Blood Cell Washing and Circuit Precirculation-Ultrafiltration on the Production of Cytokines by Open Heart Surgery (충전용 농축적혈구의 세척 및 체외순환로의 전순환-초여과법이 개심수술에 의한 사이토카인 형성에 미치는 영향)

  • 전태국;노준량
    • Journal of Chest Surgery
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    • v.35 no.3
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    • pp.199-208
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    • 2002
  • Background: The washing of packed red blood cells could remove pro-inflammatory mediators, cell debris, and micro-particles contained in packed red blood cells, and the preci-rculation-ultrafiltration (recirculation and ultrafiltration of circuit itself before cardiopulmonary bypass) could attenuate the initial inflammatory reaction and remove the initial proinflam-matory mediators. This study was performed to evaluate whether the washing of packed red blood cells and precirculation-ultrafiltration can reduce the production of cytokines that have an important role in myocardial reperfusion injury. This study investigated the effects of washing the packed red blood cells and precirculation-ultrafiltration on the production of cytokines during and after cardiopulmonary bypass and open heart surgery. Material and Method: Forty eight infants with VSD undergoing open heart surgery under cardiopulmonary bypass were randomized into control group (group C, n=12), washing group (group W, n= 12), precirculation-ultrafiltration group (group F, n: 12), and combined group(washing and precirculation-ultrafiltration, group WF, n=12). Blood samples were obtained before, during, and after the bypass to assess plasma level of tumor necrosis factor-$\alpha$(TNF-$\alpha$), interleukin-6(IL-6), and interleukin-8 (IL-8). Results: Expressions of TNF-$\alpha$ were significantly reduced in combined group (group WF) compared with group C, group W, and group F (p<0.05). Expression of IL-6 were significantly reduced in group W, group F, and group WF compared with group C (p<0.05), but similar among group W, group F, and group WF (p=0.053). Expression of IL-8 were reduced in group W and group WF compared with group C (p<0.05), but similar among group W, group F, and group WF (p=0.067). Conclusion: In conclusion, the washing of packed red blood cells and precirculation-ultrafiltration blunted the increase of TNF-$\alpha$ , IL-6, and IL-8 during and after open heart surgery with cardiopulmonary bypass. However, the clinical benefits of these treatments remains unproven.