• Title/Summary/Keyword: 전자소재

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Detection and Measurement of Nuclear Medicine Workers' Internal Radioactive Contamination (핵의학과 종사자의 방사성동위원소 체내오염 측정)

  • Jeong, Gyu-Hwan;Kim, Yong-Jae;Jang, Jeong-Chan;Lee, Jai-Ki
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.3
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    • pp.123-131
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    • 2009
  • Purpose: We tested a sample of nuclear medicine workers at Korean healthcare institutions for internal contamination with radioactive isotopes, measuring concentrations and evaluating doses of individual exposure. Materials and Methods: The detection and measurement was performed on urine samples collected from 25 nuclear medicine workers at three large hospitals located in Seoul. Urine samples were collected once a week, 100~200 mL samples were gathered up to 6~10 times weekly. A high-purity germanium detector was used to measure gamma radiations in urine samples for the presence of radioactive isotopes. Based on the detection results, we estimated the amounts of intake and committed effective doses using IMBA software. In cases where committed effective doses could not be adequately evaluated with IMBA software, we estimated individual committed effective doses for radionuclides with a very short half life such as $^{99m}Tc$ and $^{123}I$, using the methods recommended by International Atomic Energy Agency. Results: Radionuclides detected through the analysis of urine samples included $^{99m}Tc$, $^{123}I$, $^{131}I$ and $^{201}Tl$, as well as $^{18}F$, a nuclide used in Positron Emission Tomography examinations. The committed effective doses, calculated based on the radionuclide concentrations in urine samples, ranged from 0 to 5 mSv, but were, in the majority of cases, less than 1 mSv. The committed effective dose exceeded 1 mSv in three of the samples, and all three were workers directly handling radioactive sources. No nurses were found to have a committed effective dose in excess of 1 mSv. Conclusions: To improve the accuracy of results, it may be necessary to conduct a long-term study, performed over a time span wide enough to allow the clear determination of the influence of seasonal factors. A larger sample should also help increase the reliability of results. However, as most Korean nuclear medicine workers are currently not necessary to monitored routinely for internal contamination with radionuclides. Notwithstanding, a continuous effort is recommended to reduce any unnecessary exposure to radioactive substances, even if in inconsequential amounts, by regularly surveying workplace environments and frequently monitoring atmospheric concentrations of radionuclides.

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Effects of Green Tea, Cocoon Hydrolysates and Capsulated Components Mixture on Body Fat and Serum Lipid Composition in College Women in Terms of Supplemented Periods (녹차와 실크 펩타이드 및 캡슐 소재 함유 조성물이 여대생들의 복용 기간별 체지방 및 혈청 지질 성상 변화에 미치는 영향)

  • Lee, Sung-Hee;Cho, Byung-Nam;Hong, I-Jin;Lee, Min-Sook;Jew, Sang-Sup;Kim, Dong-Myung;Jin, Dong-Kyu;Rho, Sook-Nyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.5
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    • pp.715-722
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    • 2003
  • This study is to investigate effects of green tea and capsulated components mixture on body fat and serum lipid composition and fat distribution in college women students in terms of supplemented periods. During 3 months of this research, 34 college women students (average age 20.3 yr) were selected as subjects. Nutrient intake was investigated by questionnaire and 24-hr recall method. Anthropolatric assessments of the subjects were investigated by SBIA method (Segmental Bioimpedance Assay, Inbody 3.0). The results were as follows: mean body height was 162.5cm and mean body weight and mean BMI (Body Mass Index, kg/$m^2$) were 57.9kg and 21.9, respectively. Status of carbohydrate intake decreased significantly (p<0.05) and dietary fiber intake increased significantly (p<0.001) after supplementation. WHR (waist-hip ratio) decreased significantly (p<0.05) and body fat and percent body fat decreased significantly after supplementation (p<0.05). Total cholesterol and triglyceride decreased significantly after supplementation (p<0.001). Above results of this study show that green tea, silk peptide and dietary fiber supplementation-added routine diet improves body fat distribution, total cholesterol, triglyceride. Especially, declination of abdominal fat and WHR was notable, since that means diminution of risk factors for obesity and chronic degenerative diseases.

A Study on Trust and Commitment between Buyer and Supplier of Industrial Parts, and Their Usage of Information Technology (산업재 부품 구매자와 공급자의 신뢰와 몰입, 그리고 정보기술의 이용에 관한 연구)

  • Kim, Jong-Hun;Yun, Hui-Taek
    • Proceedings of the Korean DIstribution Association Conference
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    • 2006.08a
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    • pp.47-68
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    • 2006
  • This study aims to determine the association structure of the behavioral relationship variables, such as trust, commitment, cooperation, communication and coercive power, in the relationship between the buyers and suppliers of industrial parts. It also investigates the impact of the use of IT technologies on the relationships quality. Data was collected from 216 part suppliers of machinery, electronics and automobiles located in Incheon. Data supported all of the proposed hypotheses. First, it was confirmed that parts suppliers' trust in buyers leads to the commitment into relationships with buyers. Second, cooperation and communication showed a positive influence on parts suppliers' trust in buyers, and coercive power gave a negative influence on trust. Third, the use of IT technologies like Internet and E-Mail between parts suppliers and buyers was verified to have generally a positive influence on the quality of relationships. At the same time, cooperation and communication were confirmed to have a positive influence on each other, and cooperation and coercive power as well as communication and coercive power were confirmed to have negative influence on each other. This study is a pioneering attempt to examine the relationships between suppliers and buyers of industrial parts, and the influence IT technologies on the relationship quality. Also, the findings will be practically much helpful to find how to reinforce the relationships between parts suppliers and buyers.

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Composition of Flavonoids and Antioxidative Activity from Juice of Jeju Native Citrus Fruits during Maturation (수확시기별 제주재래종 감귤착즙액의 Flavonoids 분포 및 항산화 활성)

  • Kim, Yong-Dug;Ko, Weon-Jun;Koh, Kyung-Soo;Jeon, You-Jin;Kim, Soo-Hyun
    • Journal of Nutrition and Health
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    • v.42 no.3
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    • pp.278-290
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    • 2009
  • This study aims to evaluate the changes of flavonoid contents and antioxidants activity of Jeju native citrus fruits juice according to the harvest date. Flavonoids such as quercatagetin, narirutin, hesperidin and neohesperidin were contained most plentifully in the juice of Jigak (Citrus aur-antium) by 573.73 mg/100 mL, Sadoogam (C. pseudogulgul) by 393.99 mg /100 mL, Soyooja by 29.63 mg/100 mL and Jigak (C. aurantium) by 201.23 mg/100 mL in the late August, respectively. The highest contents of nob-iletin, sinensetin and tangeretin among polymethoxyflavones were found in the juice of Hongkyool (C. tachibana) by 7.39 mg/100 mL, 2.24 mg/100 mL, 0.63 mg/100 mL in the late August, respectively. 3,5,6,7,8,3',4'- Heptamet- hoxyflavone recorded the highest amount in Punkyool (C. tangerina) by 0.27 mg/100 mL in the late August, but the other polymethoxyflavones including 3',4',7,8-tetramethoxyflavone, 3',4'-dimethoxyflavone, 4'-methoxyflavone, 5,6,7,3',4',5'-hexamethoxyflavone, scutellarein tetramethylether were observed only trace amount in all the citrus fruits. Flavonoid contents in the citrus fruit juices were the highest during early maturation and decreased rapidly while ripening. Total polyphenol contents were the highest in the late August and decreased with ripening. However from the late December, the contents were increased again. Antioxidant activities of the fruits were evaluated as electron donating ability and were the lowest in the late September and increased with the fruit ripening. These results suggest that quercetagetin among all the flavonoids was most plentiful in Jigak and Dangyooja (C. grandis), so that the fruits could be used for industrial material of flavonoids and antioxidant agents.

Antioxidant and Antimicrobial Activities of Shark Collagens, and Inhibitory Actions on Elastase and Tyrosinase (상어 콜라겐의 항산화능, 항균성, Elastase 및 Tyrosinase 저해활성)

  • Kim, Jae-Won;Kim, Do-Kyun;Park, Jin-Soo;Lee, Ye-Kyung;Beik, Kyung-Yean;Kim, Soon-Dong
    • Food Science and Preservation
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    • v.16 no.3
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    • pp.419-426
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    • 2009
  • The antioxidant and antimicrobial effects of acid-soluble and pepsin-solubilizable shark (Isurus oxyrinchus) collagens (SC) (ASSC: acid-soluble shark skin collagen, ASMC: acid-soluble shark meat collagen, PSSC: pepsin-solubilizable shark skin collagen, PSMC: pepsin-solubilizable shark meat collagen) and standard marine collagen (STMC) as materials, and the ability of these materials to inhibit tyrosinase and elastase, were investigated. The electron-donating ability of SC ($1{\sim}5\;g/mL$) was $14.91{\sim}17.21%$, which was $3.0{\sim}3.6$-fold higher than that of STMC at the same concentration. Also, the SOD(superoxide dismutase)-like activity of SC (5.80 mg/mL) was $4.67{\sim}37.28%$, thus $3.0{\sim}3.6$-fold greater than that of STMC. The MIC values of SC against Staphylococcus aureus and Salmonella enteritidis were $5{\mu}g$/disc, which were remarkably lower than that of STMC ($200{\mu}g$/disc). There was no antimicrobial activity against Escherichia coli in STMC, but the MIC against E. coli was $200{\mu}g$/disc for acid-soluble SC and $100{\mu}g$/disc for pepsin-solubilizable SC. The inhibition of tyrosinase by SC (3-5 mg/mL) was $58.95{\sim}98.16%$, $3.34{\sim}3.74$-fold higher than that of STMC ($17.67{\sim}26.25%$). Also, elastase inhibition by SC (at 1 mg/mL) was $53.33{\sim}80.0%$, $1.1{\sim}4.0$-fold greater than that of STMC. These results indicated that shark collagens may be valuable new functional materials owing to their antioxidant and antimicrobial properties, and because the inhibitory activities against elastase and tyrosinase are better than those of standard marine collagen.

Electrochemical Characteristics of LiMn2O4 Cathodes Synthesized from Various Precursors of Manganese Oxide and Manganese Hydroxide (다양한 형태 및 구조의 망간산화물 및 망간수산화물 전구체로부터 합성한 LiMn2O4양극의 전기화학적 특성 연구)

  • Lee, Jong-Moon;Kim, Joo-Seong;Hong, Soon-Kie;Lee, Jeong-Jin;Ahn, Han-Cheol;Cho, Won-Il;Mho, Sun-Il
    • Journal of the Korean Electrochemical Society
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    • v.15 no.3
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    • pp.172-180
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    • 2012
  • The $LiMn_2O_4$ cathodes for lithium ion battery were synthesized from various precursors of manganese oxides and manganese hydroxides. As the first step, nanosized precursors such as ${\alpha}-MnO_2$ (nano-sticks), ${\beta}-MnO_2$ (nano-rods), $Mn_3O_4$ (nano-octahedra), amorphous $MnO_2$(nano-spheres), and $Mn(OH)_2$ (nano-plates) were prepared by a hydrothermal or a precipitation method. Spinel $LiMn_2O_4$ with various sizes and shapes were finally synthesized by a solid-state reaction method from the manganese precursors and LiOH. Nano-sized (500 nm) octahedron $LiMn_2O_4$ showed high capacities of 107 mAh $g^{-1}$ and 99 mAh $g^{-1}$ at 1 C- and 50 C-rate, respectively. Three dimensional octahedral crystallites exhibit superior electrochemical characteristics to the other one-dimensional and two-dimensional shaped $LiMn_2O_4$ nanoparticles. After 500 consecutive charge discharge battery cycles at 10 C-rate with the nano-octahedron $LiMn_2O_4$ cathode, the capacity retention of 95% was observed, which is far better than any other morphologies studied in this work.

Effects of Jeju Citrus unshiu Peel Extracts Before and After Bioconversion with Cytolase on Anti-Inflammatory Activity in RAW264.7 Cells (면역세포에서 Bioconversion 전후 제주 감귤 과피 추출물의 항염증 효과)

  • Seo, Jieun;Lim, Heejin;Chang, Yun-Hee;Park, Hye-Ryeon;Han, Bok-Kyung;Jeong, Jung-Ky;Choi, Kyoung-Sook;Park, Su-Beom;Choi, Hyuk-Joon;Hwang, Jinah
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.3
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    • pp.331-337
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    • 2015
  • Citrus and its peels, which are by-products from juice and/or jam processing, have long been used in Asian folk medicine. Citrus peels show an abundant variety of flavanones, and these flavanones have glycone and aglycone forms. Aglycones are more potent than glycones with a variety of physiological functions since aglycone absorption is more efficient than glycones. Bioconversion with cytolase converted narirutin and naringin into naringenin and hesperidin into hesperetin. Therefore, this study aimed to investigate the anti-oxidant and anti-inflammatory effects of bioconversion of Citrus unshiu (CU) peel extracts with cytolase (CU-C) in RAW264.7 cells. HPLC chromatograms showed that CU and CU-C had 23.42% and 29.39% total flavonoids, respectively. There was substantial bioconversion of narirutin to naringenin and of hesperidin to hesperetin. All citrus peel extracts showed DPPH scavenging activities in a dose-dependent manner, and CU-C was more potent than intact CU. RAW264.7 cells were pre-treated with $0{\sim}500{\mu}g/mL$ of citrus peel extracts for 4 h and then stimulated by $1{\mu}g/mL$ of lipopolysaccharide (LPS) for 8 h. All citrus peel extracts showed decreased mRNA levels and protein expression of LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose-dependent manner. Especially, CU-C markedly inhibited mRNA and protein expression of iNOS and COX-2 compared to intact citrus peel extracts. All citrus peel extracts showed decreased NO production by iNOS activity. This result suggests that bioconversion of citrus peel extracts with cytolase may provide potent functional food materials for prevention of chronic diseases attributable to oxidation and inflammation by boosting the anti-inflammatory effects of citrus peels.

A Study on the Application Direction of Finite Element Analysis in the Field of Packaging through Research Trend Analysis in Korea (국내 연구 동향 분석을 통한 포장분야에서 유한요소해석의 적용 방향에 관한 고찰)

  • Lee, Hakrae;Jeon, Kyubae;Ko, Euisuk;Shim, Woncheol;Kang, Wookgun;Kim, Jaineung
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.23 no.3
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    • pp.191-200
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    • 2017
  • Proper packaging design can meet both the environmental and economic aspects of packaging materials by reducing the use of packaging materials, waste generation, material costs, and logistics costs. Finite element analysis(FEM) is used as a useful tool in various fields such as structural analysis, heat transfer, fluid motion, and electromagnetic field, but its application in the field of packaging is still insufficient. Therefore, the application of FEM to the field of packaging can save the cost and time in the future research because it is possible to design the package by computer simulation, and it is possible to reduce the packaging waste and logistics cost through proper packaging design. Therefore, this study investigated the FEM papers published in Korea for the purpose of helping research design using FEM program in the field of packaging in the future. In this paper, we analyzed the 29 papers that were directly related to the analysis of FEM papers published in domestic journals from 1991 to 2017. As a result, we analyzed the research topic, FEM program, and analysis method using each paper, and presented the direction that can be applied in future packaging field. When the FEM is applied to the packaging field, it is possible to change the structure and reduce the thickness through the stress and vibration analysis applied to the packaging material, thereby reducing the cost by improving the mechanical strength and reducing the amount of the packaging material. Therefore, in the field of packaging research in the future, if the FEM is performed together, economical and reasonable packaging design will be possible.

Physiological Activities of Extract from Edible Mushrooms (주요 식용버섯 추출물의 생리활성 효과)

  • Choi, Se-Jin;Lee, Yeon-Sil;Kim, Jin-Kyung;Kim, Jin-Kyu;Lim, Soon-Sung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.8
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    • pp.1087-1096
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    • 2010
  • This study was conducted to investigate the physiological activity of extracts of fresh mushrooms. The components were extracted by hot water; subsequently, the hot-water extract was subjected to 60% ethanol precipitation to yield high-molecular-weight (HMW) and low-molecular-weight (LMW) fractions. Total polyphenol contents, $\beta$-glucan contents, electron-donating ability (EDA), superoxide dismutase (SOD)-like activity, nitrite-scavenging activity, fibrinolytic activity, nitric oxide (NO) production, and inhibition of NO production of the mushroom extracts were measured using lipopolysaccharide (LPS)-stimulated murine macrophages, RAW 264.7 cells. The extracts of Lentinus edodes (Berk.) Singer and Pleurotus ostreatus (Fr.) Kummer contained the highest levels of $\beta$-glucan (33.5% and 25.57%, respectively). Further, the LMW fractions of the Phellinus linteus contained the highest levels of polyphenols (233.23 mg/g). The EDA of LMW fractions (10 mg/mL) of the Phellinus linteus and Agaricus bisporus were 80.74% and 51.35%, respectively. Further, SOD-like activities of the LMW fractions were high as compared to those of the HMW fractions. Nitrite-scavenging activities of the LMW fractions (pH 1.2; concentration, 10 mg/mL) of the Phellinus linteus and Pleurotus ostreatus (Fr.) Kummer were 75.95% and 41.05%, respectively. The fibrinolytic activity of the LMW fractions of all mushrooms showed no enzyme activity by fibrin plate assay. The fibrinolytic activity of the extracts of Tricholoma matsutake was the greatest inhibitory activity at 60.4%. Further study revealed that the mushroom extracts exhibited anti-inflammatory effects on RAW 264.7 cells. The LMW fraction ($500\;{\mu}g/mL$) of the Phellinus linteus considerably inhibited NO production (100%).

Study of Anti-oxidant Analysis to Vegetable Juice Containing Barley Sprouts (보리새싹 함유 녹즙의 항산화력 분석에 관한 연구)

  • Yoo, In-Sik;Baek, Cheong-Mok;Joung, Mi-Yeun;Kwon, Sang-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.12
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    • pp.248-253
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    • 2017
  • This study was conducted to analyze the anti-oxidant activity of green juice containing barley sprouts. The specimens used in the experiments were supplied byCSJ company located in Jincheon-gun, Chungbuk province. Polyphenol and flavonoid was detected in Huttuynia cordata Thunb fermentation sprout juiceat $1.075{\pm}0.174mg/mL$ and $2.736{\pm}0.187\;quercetin\;mg/mL$, in organic dandelion at $1.048{\pm}0.173mg/mL$ and $2.685{\pm}0.245\;quercetin\;mg/mL$, kan andRakat $1.013{\pm}0.083mg/mL$ and $3.624{\pm}0.237\;quercetin\;mg/mL$, broccoli blending juice at $1.494{\pm}0.255mg/mL$ and $3.826{\pm}0.286\;quercetin\;mg/mL$, and barley sprouts at $1.043{\pm}0.220mg/mL$ and $1.990{\pm}0.223\;quercetin\;mg/mL$, respectively.Antioxidant activity testing revealed the electron donating ability of Huttuynia cordata Thunb fermentation sprout juice for DPPH was 81.97%. Moreover, the free radical scavenging ability measured by ABTS assay showed that the activity was increased in the order of broccoli blending juice, Huttuynia cordata Thunb fermentation sprout juice, organic dandelion, 'kan andRak', barley sprout, and thatthe effects were similar to those of ascorbic acid at $100{\mu}g/mL$. Statistical processing is using SPSS 24, analysis of distributed layout and Duncan's multiple range (p<0.05). Therefore, the use of functional assistance material of products in the future indicates that it is worth a healthy functional drink.