• Title/Summary/Keyword: 조직 변화

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Anti-tumor and Anti-inflammatory Effects of Ecklonia cava in CT26 Tumor-bearing BALB/cKorl Syngeneic Mice (CT26 고형암을 내포하는 BALB/cKorl Syngeneic 마우스에서 Ecklonia cava의 항암효과 및 항염증효과)

  • Yu Jeong Roh;Ji Eun Kim;You Jeong Jin;Ayun Seol;Hee Jin Song;Tae Ryeol Kim;Kyeong Seon Min;Eun Seo Park;Ki Ho Park;Dae Youn Hwang
    • Journal of Life Science
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    • v.33 no.11
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    • pp.887-896
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    • 2023
  • The inflammatory response have been considered as one of important targets for cancer treatment because they play a key role during all steps of tumor development including initiation, promotion, malignant conversion and progression. To investigate the anti-inflammatory response during anti-tumor activity of an aqueous extracts of Ecklonia cava (AEC), alterations on the distribution of mast cells and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), nuclear factor (NF)-κB, inflammasome compositional protein and inflammatory cytokines were examined in CT26 colon tumor-bearing BALB/cKorl syngeneic mice after administrating AEC for five weeks. After treatment of AEC, total weight of tumor and necrotic region of tumor section were significantly decreased compared to vehicle treated group. The number of infiltered mast cells was higher in AEC treated group than vehicle treated group, while the expression levels of COX-2 and iNOS were decreased in AEC treated group. Also, similar decrease pattern were detected in the expression levels of NF-κB, NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and caspase-1 (Cas-1) after AEC treatment although the decrease rate was varied. Furthermore, the mRNA expressions of three inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α) and interleukin-6 (IL-6) were remarkably decreased in AEC treated group compared to vehicle treated group. These results suggest that inhibition of inflammatory response may be tightly associated with anti-tumor activity of AEC in CT26 colon tumor-bearing BALB/cKorl syngeneic mice.

Effects of Korean Goldenbell (Forsythia koreana) Leaf on the Growth, Body Color and Hepatopancreatic Structure of Giant Freshwater Prawn (Macrobrachium rosenbergii) (큰징거미새우(Macrobrachium rosenbergii)의 성장, 체색 및 간췌장 구조에 미치는 개나리(Forsythia koreana) 잎의 영향)

  • Dong Woo Kim;Jeong Hee Yoon;Ji Eun Ha;Jeong Hee Min;Bo Ryung Park;Joon Yeong Kwon
    • Journal of Marine Life Science
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    • v.8 no.2
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    • pp.166-177
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    • 2023
  • The giant freshwater prawn (Macrobrachium rosenbergii) suffers economic losses in aquaculture facilities due to problems such as poor body color and carapace weakness. While this species is farmed on an animal-based diet, in the wild it consumes a detritus diet with a high proportion of plant matter. The plant matter they consume in the wild is not only a source of basic nutrients, but also carotenoids, which are responsible for body color. Korean goldenbell (Forsythia koreana) is a flowering tree widely distributed in Korea, and its leaves contain carotenoids comparable to yellow carrots. In this study, we investigated the effects of feeding Forsythia leaves to M. rosenbergii on their body color and health. The experimental diets were 100% commercial feed (control), CON, 80% commercial feed plus 20% Forsythia leaf powder, FP, and 80% commercial feed plus 20% unprocessed Forsythia leaves, FL, and each diet was fed to juvenile prawn with an average weight of 1.1 ± 0.2 g for 10 weeks. In terms of body color, the CON prawn were consistently clear ivory in color, while the FP and FL prawn changed from blue to dark brown as the days of rearing progressed. Survival and growth were not significantly different between CON and FP or FL. Histological comparison of the hepatopancreas revealed that the vacuole size of B cells, the constituent cells of the hepatopancreatic tubule, was significantly larger in FP and FL compared to CON. The vacuoles of B cells are responsible for the absorption and digestion of nutrients, suggesting that the supply of Forsythia leaves may have had a positive effect on the health of the M. rosenbergii. The above results show that the use of Forsythia leaves in the aquaculture of M. rosenbergii can be expected to improve body color and health without inhibiting growth.

Growth stage-specific changes in fruiting body characteristics of Pleurotus spp. (생육시기에 따른 느타리류의 자실체 특성 변화)

  • Jae-San Ryu;Kyeong Sook Na
    • Journal of Mushroom
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    • v.21 no.4
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    • pp.254-260
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    • 2023
  • The characteristics and spore production of Gonji7ho, Bunhong, and Sunjung fruiting bodies were assessed at different growth stages. The shape of the Pleurotus species fruiting body starts out short and small, then takes on a typical mushroom shape as it grows. Gonji7ho has a long stalk, Bunhong has a short stalk and a wide cap, and Sunjung's cap and stalk dimensions are intermediate. Each variety displayed deep color at the beginning of growth but became steadily lighter with continued growth. The shape of the linkage between the mushroom stalk and cap changed from an initial central position to a lateral position after the growing stage. Gonji7ho cap diameter increased 7-fold from 15.5 mm (5 days of growth) to 37.9 mm (9 days of growth). Growth rates for each growth day measured using the growth percentage of the previous day were 285.5% (5 → 6th day), 182.2% (6 → 7th day), 129.4% (7 → 8th day), and 103.8% (8 → 9th day). This trend was also observed in Bunhong and Sunjung, but Bunhong's growth rate was more rapid (4.9 fold on day 6, 2.7 fold on day 7) and continued to increase through day 9. Harvest yield, which is of greatest interest to farmers, displayed a similar trend spanning the growth period, as did cap diameter. Gonji7ho harvest yield increased rapidly until day 7 of growth (more than 177%), then growth slowed down beginning around day 8, and further decreased on day 9 (98%). Similar trends were observed in Bunhong and Sunjung. Bunhong showed characteristic rapid growth in harvest yield (4.9 fold compared to the previous day on day 6 and 2.7 fold on day 7), and the increase continued through day 9. A decrease in mushroom harvest yield commonly seen in the late growth stage is thought to be due to the death of some mushrooms and decomposition of cap tissue. Basidiospore content increased with number of growth days but decreased after day 8. Gonji7ho yielded the highest production on day 7 of growth, coinciding with harvest time, with 209,000,000 spores. This trend was also observed in Bunhong and Sunjung. These results will provide researchers with basal data and guide farmers in selecting the optimal harvest day.

The Evaluation of the Packaging Properties and Recyclability with Modified Acrylic Emulsion for Flexible Food Paper Coating (유연 종이 식품 포장재의 개질 아크릴 에멀젼 코팅 특성 및 재활용성 평가)

  • Myungho Lee;In Seok Cho;Dong Cheol Lee;Youn Suk Lee
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.29 no.3
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    • pp.153-161
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    • 2023
  • The worldwide effects of COVID-19 have led to a surge in online shopping and contactless services. The consumption pattern has caused the issues such as the environmental pollution together with the increase of plastic waste. Reducing the reliance on the petroleum based plastic use for the package and replacing it with environmentally friendly material are the simple ways in order to solve those problems. Paper is an eco-friendly product with high recyclability as the food packaging materials but has still poor barrier properties. A barrier coating on surface of the paper can be achieved with the proper packaging materials featuring water, gas and grease barrier. Polyethylene (PE) or polypropylene (PP) coatings which are generally laminated or coated to paper are widely used in food packaging applications to protect products from moisture and provide water or grease resistance. However, recycling of packaging containing PE or PP matrix is limited and costly because those films are difficult to degrade in the environment. This study investigated the recyclability of modified acrylic emulsion coating papers compared to PE and PP polymer matrixes as well as their mechanical and gas barrier properties. The results showed that PE or modified acrylic emulsion coated papers had better mechanical properties compared to the uncoated paper as a control. PE or PP coating papers showed strong oil resistance property, achieving a kit rating of 12. Those papers also had a significantly higher percentage of screen reject during the recycling process than modified acrylic coated paper which had a screen rejection rate of 6.25%. In addition an uncoated paper had similar value of a screen rejection rate. It may suggest that modified acrylic emulsion coating paper can be more easily recycled than PE or PP coating papers. The overall results of the study found that modified acrylic emulsion coating paper would be a viable alternative to suggest a possible solution to an environmental problem as well as enhancing the weak mechanical and poor gas barrier properties of the paper against moisture.

Text Mining-Based Emerging Trend Analysis for e-Learning Contents Targeting for CEO (텍스트마이닝을 통한 최고경영자 대상 이러닝 콘텐츠 트렌드 분석)

  • Kyung-Hoon Kim;Myungsin Chae;Byungtae Lee
    • Information Systems Review
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    • v.19 no.2
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    • pp.1-19
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    • 2017
  • Original scripts of e-learning lectures for the CEOs of corporation S were analyzed using topic analysis, which is a text mining method. Twenty-two topics were extracted based on the keywords chosen from five-year records that ranged from 2011 to 2015. Research analysis was then conducted on various issues. Promising topics were selected through evaluation and element analysis of the members of each topic. In management and economics, members demonstrated high satisfaction and interest toward topics in marketing strategy, human resource management, and communication. Philosophy, history of war, and history demonstrated high interest and satisfaction in the field of humanities, whereas mind health showed high interest and satisfaction in the field of in lifestyle. Studies were also conducted to identify topics on the proportion of content, but these studies failed to increase member satisfaction. In the field of IT, educational content responds sensitively to change of the times, but it may not increase the interest and satisfaction of members. The present study found that content production for CEOs should draw out deep implications for value innovation through technology application instead of simply ending the technical aspect of information delivery. Previous studies classified contents superficially based on the name of content program when analyzing the status of content operation. However, text mining can derive deep content and subject classification based on the contents of unstructured data script. This approach can examine current shortages and necessary fields if the service contents of the themes are displayed by year. This study was based on data obtained from influential e-learning companies in Korea. Obtaining practical results was difficult because data were not acquired from portal sites or social networking service. The content of e-learning trends of CEOs were analyzed. Data analysis was also conducted on the intellectual interests of CEOs in each field.

Studies on Neck Blast Infection of Rice Plant (벼 이삭목도열병(病)의 감염(感染)에 관(關)한 연구(硏究))

  • Kim, Hong Gi;Park, Jong Seong
    • Korean Journal of Agricultural Science
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    • v.12 no.2
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    • pp.206-241
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    • 1985
  • Attempts to search infection period, infection speed in the tissue of neck blast of rice plant, location of inoculum source and effects of several conditions about the leaf sheath of rice plants for neck blast incidence have been made. 1. The most infectious period for neck blast incidence was the booting stage just before heading date, and most of necks have been infected during the booting stage and on heading date. But $Indica{\times}Japonica$ hybrid varieties had shown always high possibility for infection after booting stage. 2. Incubation period for neck blast of rice plants under natural conditions had rather a long period ranging from 10 to 22 days. Under artificial inoculation condition incubation period in the young panicle was shorter than in the old panicle. Panicles that emerged from the sheath of flag leaf had long incubation period, with a low infection rate and they also shown slow infection speed in the tissue. 3. Considering the incubation period of neck blast of rice plant, we assumed that the most effective application periods of chemicals are 5-10 days for immediate effective chemicals and 10-15 days for slow effective chemicals before heading. 4. Infiltration of conidia into the leaf sheath of rice plant carried out by saturation effect with water through the suture of the upper three leaves. The number of conidia observed in the leaf sheath during the booting stage were higher than those in the leaf sheath during other stages. Ligule had protected to infiltrate of conidia into the leaf sheath. 5. When conidia were infiltrated into the leaf sheath, the highest number of attached conidia was observed on the panicle base and panicle axis with hairs and degenerated panicle, which seemed to promote the infection of neck blast. 6. The lowest spore concentration for neck blast incidence was variable with rice varietal groups. $Indica{\times}Japonica$ hybrid varieties were infected easily compared to the Japonica type varieties, especially. The number of spores for neck blast incidence in $Indica{\times}Japonica$ hybrid varieties was less than 100 and disease index was higher also in $Indica{\times}Japonica$ hybrid than in Japonica type varieties. 7. Nitrogen content and silicate content were related with blast incidence in necks of rice plants in the different growing stage changed during growing period. Nitrogen content increased from booting stage to heading date and then decreased gradually as time passes. Silicate content increased from booting stage after heading with time. Change of these content promoted to increase neck blast infection. 8. Conidia moved to rice plant by ascending and desending dispersal and then attached on the rice plant. Conidia transfered horizontally was found very negligible. So we presumed that infection rate of neck blast was very low after emergence of panicle base from the leaf sheath. Also ascending air current by temperature difference between upper and lower side of rice plant seemed to increase the liberation of spores. 9. Conidial number of the blast fungus collected just before and after heading date was closely related with neck blast incidence. Lesions on three leaves from the top were closely related with neck blast incidence, because they had high potential for conidia formation of rice blast fungus and they were direct inoculum sources for neck blast. 10. The condition inside the leaf sheath was very favorable for the incidence of neck blast and the neck blast incidence in the leaf sheath increased as the level of fertilizer applied increased. Therefore, the infection rate of neck blast on the all panicle parts such as panicle base, panicle branches, spikelets, nodes, and internodes inside the leaf sheath didn't show differences due to varietal resistance or fertilizers applied. 11. Except for others among dominant species of fungi in the leaf sheath, only Gerlachia oryzae appeared to promote incidence of neck blast. It was assumed that days for heading of varieties were related with neck blast incidence.

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The effects of proliferation and differentiation on adipocyte 3T3-L1 by prescriptions and herbs of Taeyang-In and Taeum-In (태양인(太陽人), 태음인(太陰人)의 처방(處方)과 약재(藥材)가 지방세포(脂肪細胞)(3T3-L1)의 증식(增殖)·분화억제(分化抑制)에 미치는 영향(影響))

  • Kim, Su-beom;Kho, Byung-hee;Song, Il-byung
    • Journal of Sasang Constitutional Medicine
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    • v.10 no.2
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    • pp.533-564
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    • 1998
  • In order to know the effect of proliferation and differentiation on edipocyte 3T3-L1 by prescriptions and herbs, Taeyangin(太陽人)'s Okapijangcheok-tang(五加皮壯脊湯) Mihudeungsikjangtang Acanthopanacis Cortex(五加皮) Phragmitis Rhizoma(蘆根) and Taeumin(太陰人)'s Taeumjowi-tang(太陰調胃湯) Cheongsimyonja-tang(淸心蓮子湯) Cheongpaesagan-tang(淸肺瀉肝湯) Galkeunbupyong-tang(葛根浮萍湯) Coicis Semen(薏苡仁) Rhei Undulati Rhizoma(大黃) Mori Cortex(桑白皮) Ulmi Cortex(楡根白皮) Holotrichia Vermiculus Kalopanaxii Cortex(海桐皮) Ephedrae Herba(麻黃) Imperatae Rhizoma(白茅根), were used and had some effects. 1. The proliferation effect of edipocyte 1) At the Taeyangin(太陽人)'s prescriptions and herbs, Okapijangcheok-tang(五加皮壯脊湯) Mihudeungsikjang-tang Acanthopanacis Cortex(五加皮) have a control effect at the boiling water-extract and ethyl alcohol-extract. Phragmitis Rhizoma(蘆根) have a control effect at the ethyl alcohol-extract. 2) At the Taeyangin(太陽人)'s prescriptions and herbs, Taeumjowi-tang(太陰調胃湯) Cheongsimyonja-tang(淸心蓮子湯) Cheongpaesagan-tang(淸肺瀉肝湯) Galkeunbupyong-tang(葛根浮萍湯) have a control effect at the boiling water-extract and ethyl alcohol-extract. Coicis Semen(薏苡仁) Rhei Undulati Rhizoma(大黃) Morl Cortex(桑白皮) Ulmi Cortex(楡根白皮) Kalopanaxii Cortex(海桐皮) · Ephedrae Herba(麻黃) of the boiling water-extract, Holotrichia Vermiculus Kalopanaxii Cortex(海桐皮) of ethyl alcohol-extract have a control effect on edipocytes. Rhei Undulati Rhizoma(大黃) Ulmi Cortex(楡根白皮) Ephedrae Herba(麻黃) of high-density have a cyto-toxicity. 2. The differentiation effect of edipocyte 1) At the Taeyangin(太陽人)'s prescriptions and herbs during the natural differentiation, Phragmitis Rhizoma(蘆根) of the boiling water-extract, Okapijangchek-tang(五加皮壯脊湯) Acanthopanacis Cortex(五加皮) of the ethyl alcohol-extract have a cyto-toxicity on the first-differentiation. 2) At the Taeumin(太陰人)'s prescriptions and herbs during the natural differentiation, Ulmi Cortex (楡根白皮) Kalopanaxii Cortex(海桐皮) of the boiling water-extract have a cyto-toxicity on the first-differentiation. Cheongsimyonja-tang(淸心蓮子湯) Ephedrae Herba(麻黃) of ethyl alcohol-extract have a control effect on the redifferentiation. 3) At the Taeyangin(太陽人)'s prescriptions and herbs on the first-differentiation during the induced differentiation, Acanthopanacis Cortex(五加皮) of ethyl alcohol-extract has a control effect. Okapijangchek-tang(五加皮壯脊湯) Acanthopanacis Cortex(五加皮) Phragmitis Rhizoma(蘆根) of the boiling water-extract have a cyto-toxicity. 4) At the Taeumin(太陰人)'s prescriptions and herbs on the first-differentiation during the induced differentiation, Coicis Semen(薏苡仁) Ephedrae Herba(麻黃) Imperatae Rhizoma(白茅根) of the boiling water-extract and Ephedrae Herba(麻黃) of the ethyl alcohol-extract have a control effect. Kalopanaxii Cortex(海桐皮) of the boiling water-extract and the ethyl alcohol-extract has a cyto-toxicity. Considering this result, the Taeyangin(太陽人) Taeumin(太陰人)'s prescriptions and herbs have a control effect on edipocytes during the proliferation. Acanthopanacis Cortex(五加皮), Coicis Semen(薏苡仁) Ephedrae Herba(麻黃) Imperatae Rhizoma(白茅根) have a control effect on edipocytes during the induced differentiation. In the future, for treating a obesity need a vivo assay and hope this study to help to know the mechanisms of obesity.

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LINAC-based Stereotactic Radiosurgery for Meningiomas (수막종에 대한 선형가속기형 정위방사선수술)

  • Shin Seong Soo;Kim Dae Yong;Ahn Yong Chan;Lee Jung Il;Nam Do-Hyun;Lim Do Hoon;Huh Seung Jae;Yeo Inhwan J;Shin Hyung Jin;Park Kwan;Kim BoKyoung;Kim Jong Hyun
    • Radiation Oncology Journal
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    • v.19 no.2
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    • pp.87-94
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    • 2001
  • Purpose : To evaluate the role of LINAC-based stereotactic radiosurgery (SRS) in the management of meningiomas, we reviewed clinical response, image response, neurological deficits for patients treated at our institution. Methods and materials : Between February 1995 and December 1999, twenty-six patients were treated with SRS. Seven patients had undergone prior resection. Nineteen patients received SRS as the initial treatment. There were 7 male and 19 female patients. The median age was 51 years (range, $14\~67\;years$). At least one clinical symptom presented at the time of SRS in 17 patients and cranial neuropathy was seen in 7 patients. The median tumor volume was $4.7\;cm^3\;(range,\;0.7\~16.5\;m^3)$. The mean marginal dose was 15 Gy (range, $10\~20\;Gy$), delivered to the $80\%$ isodose surface (range, $46\~90\%$). The median clinical and imaging follow-up periods were 27 months (range, 1-71 months) and 25 months (range, $1\~52\;months$), respectively. Results : Of 14 patients who had clinical follow-up of one year or longer, thirteen patients $(93\%)$ were improved clinically at follow-up examination. Clinical symptom worsened in one patient at 4 months after SRS as a result of intratumoral edema, who underwent surgical resection at 7 months. OF 14 patients who had radiologic follow-up of one year or longer, tumor volume decreased in 7 patients $(50\%)$ at a median of 11 months (range, $6\~25\;months$), remained stable in 6 patients $(43\%)$, and increased in one patient $(7\%)$, who underwent surgical resection at 44 months. New radiation-induced neurological deficits developed in six patients $(23\%)$. Five patients $(19\%)$ had transient neurological deficits, completely resolved by conservative treatment including steroid therapy. Radiation-induced brain necrosis developed in one patient $(3.8\%)$ at 9 months after SRS who followed by surgical resection of tumor and necrotic tissue. Conclusions : LINAC-based SRS proves to be an effective and safe management strategy for small to moderate sized meningiomas, inoperable, residual, and recurrent, but long-term follow-up will be necessary to fully evaluate its efficacy. To reduce the radiation-induced neurological deficit for large size meningioma and/or in the proximity of critical and neural structure, more delicate treatment planning and optimal decision of radiation dose will be necessary.

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The effects of fluoride releasing orthodontic sealants on the prevention and the progressive inhibition of enamel demiheralization in vitro (광중합형 및 자가중합형 교정용 전색제의 치아우식예방 및 진행억제효과에 관한 실험적 연구)

  • Chae, Seung-Won;Cho, Jae-O;Yoon, Young-Jooh;Kim, Kwang-Won
    • The korean journal of orthodontics
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    • v.27 no.6 s.65
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    • pp.979-995
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    • 1997
  • The purpose of this study was to identify the preventive and the progressive inhibitory effects of enamel demineralization with fluoride releasing light-and self-cured orthodontic sealants(FluoroBond), in vitro, under the polarizing light microscope and the scanning electon microscope. The polarizing light microscopic group was subdivided into seven groups(Group A-Group G). The scanning electron microscopic group was also subdivided into seven groups(Group A'-Goup G'). For polarizing light microscopic evaluation, longitudinal sections were made longitudinally by Maruto cutter(Maruto Co., Japan) and Maruto grinding machine(Maruto Co., Japan). Sections were examined and photographed by the polarizing light microscope(Olympus Optical Co., Japan) using crossed polars and with the enamel rod longitudinal axis oriented at $45^{\circ}$ to the extinction position. For scanning electron microscopic evaluation, the specimens were coated with a highly conducting layer of gold palladium in a model Hus-4 high-vacuum evaporator and examined in an ISI-100B scanning electron microcope operated at 20kV. The results of this study were as follows : 1. The mean depths of artificial carious lesions under a polarized light microscope were $Group\;A(5.08{\mu}m),\;Group\;B(47.82{\mu}m,\;Group\;C(8.42{\mu}m),\;Group\;D(7.20{\mu}m),\;Group\;E(85.41{\mu}m),\;Group\;F(60.38{\mu}m),\;Group\;G(60.13{\mu}m)$. 2. There were statistically significant differences in Group B compared with Group A, C, and D(p<0.05), and also, in Group I compared with Group F and Group G(p<0.05). 3. Light-and self-cured orthodontic sealants had the preventive effects of enamel demineralization. 4. Light-and self-cured orthodontic sealants had the progressive inhibitory effects of enamel demineralization. 5. The time progress of demineralizing agent had no influence on the samples of light-and self-cured orthodontic sealants under the scanning electron microscope. 6. There was no difference between the specimens of light-and self-cured orthodontic sealants both in the polarized light microscopic group and in the scanning electron microscopic group.

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Experimental Investigation of Stannite-Sphalerite System In Relation to Ores (황석석일섬아연석계(黃錫石一閃亞鉛石系)의 실험연구(實驗硏究)와 천연건물(天然鍵物)에의 활용(活用))

  • Lee, Jae Yeong
    • Economic and Environmental Geology
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    • v.8 no.1
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    • pp.1-23
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    • 1975
  • The subject of this study deals with phase relations between stannite ($Cu_2FeSnS_4$) and sphalerite (${\beta}-ZnS$)/wurtzite (${\alpha}-ZnS$). The phase relations were systematically investigated from liquidus temperature to $400^{\circ}C$ under controlled conditions. ${\beta}-stannite$ (tetragonal) is stable up to $706{\pm}5^{\circ}C$, where it inverts to a high-temperature polymorph ${\alpha}-stannite$ (cubic) melting congruently at $867{\pm}5^{\circ}C$. Sphalerite (cubic, ${\beta}-ZnS$) inverts at $1013{\pm}3^{\circ}C$ to wurtzite, which is the hexagonal hightemperature polymorph of ZnS. Between ${\alpha}-stannite$ and sphalerite a complete solid solution series exists above approximately $870^{\circ}C$ up to solidus temperature. The melting temperature of ${\alpha}-stannite$ rises towards sphalerite and reaches a maximum at $1074{\pm}3^{\circ}C$, which is the peritectic with the composition of 91 wt. % sphalerite and 9 wt. % ${\alpha}-stannite$. At this temperature, wurtzite takes only 5wt. % ${\alpha}-stannite$ in solid solution which decreases with increasing temperature. The inverson temperature of ${\alpha}/{\beta}-stannite$ is lowered with increasing amounts of sphalerite in solid solution down to $614{\pm}7^{\circ}C$, which is the eutectoid with the composition of 13 wt. % sphalerite and 87 wt. % ${\alpha}-stannite$. Here, ${\beta}-stannite$ contains only 10wt. % sphalerite in solid solution. With decreasing temperature, the ranges of the solid solution on both sides of the system narrow. The phase relations in the above pure system changed due to the FeS impurities in the sphalerite solid solution. The eutectoid increased from $614{\pm}7^{\circ}C$ up to $695{\pm}5^{\circ}C$ (5 wt. % FeS) and $700{\pm}5^{\circ}C$ (10wt. % FeS), while the peritectic decreased from $1074{\pm}3^{\circ}C$ down to $1036{\pm}3^{\circ}C$ (wt. %FeS) and $987{\pm}3^{\circ}C$ (10wt. %FeS). A most notable change is the appearance of non-binary regions. An important feature is the combination of this study system with the experimental results reported by Sprinfer (1972). If a stannite-kesterite solid solution is used in the place of stannite as a bulk composition, the inversion temperature is lowered to less than $400^{\circ}C$ which belongs to temperatures of the hydrothermal region.

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