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Studies on the Heavy Metals of Common Restaurant Meals (대중음식중 중금속 함량)

  • Kim, Jung-Hun;Chough, Nam-Joon;Park, Sung-Bae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.18 no.3
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    • pp.316-320
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    • 1989
  • This study was performed to assess the contamination levels of the heavy metals (Pb, Cd, Cr, Cu, Fe, Zn and Mn) for common restaurant meals in Seoul area. The samples were seolong-tang, galbi-tang, yeukge-jang, kalguksoo, doenjang-chige, bibim-bab, bibim-nangmyon, bulgogi, chazang-myon, yanggobchang and zumuluk, which were seperated draind residues from fluids. The heavy metal contents were determined by atomic absorption spectrophotometer. The results obtained were as follows : ${\circ}$ The total amount of heavy metals per meals were $131.8{\mu}g\;lead,\;18.4{\mu}g\;cadmium,\;135.5{\mu}g\;chromium,\;804.9{\mu}g\;copper,\;7430.6{\mu}g\;iron,\;2807.4{\mu}g\;zinc,\;and\;841.6{\mu}g$ manganese. ${\circ}$ Intake levels per daily through common restaurant meals were lower than the daily intake limit established by FAO/WHO.

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Effect of Polyamine on Hairy Root Culture of Bupleurum falcatum L. (Polyamine이 시호의 모상근 배양에 미치는 영향)

  • 표병식;김영준황백
    • KSBB Journal
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    • v.10 no.4
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    • pp.435-440
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    • 1995
  • During culture the effect of polyamine on hairy root of Buplerum falcatum by infection of Agrobacterium rhizogenes was studied. The fresh and dry weight of hairy root which cultured for 3months in MS medium increased about 7-fold when spermine at 10${\mu}$M, 100${\mu}$M was treated. After suspension culture of B. falcatum in MS medium containing putrescine(10${\mu}$M, 100${\mu}$M) or spermine(10${\mu}$M), the contents of endogenous polyamine (putresclne, spermidine, spermine) was higher than that of control. The ${\beta}$-glucan synthetase II activity by polyamine treatment was increased: especially spermidine (100${\mu}$M) and spermine(100${\mu}$M) stimulated it by about 180% and 220% respectively. These results suggest a possible role of polyamine as growth regulator in B. falcatum hairy root cultures.

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Anticancer Activity of Glycyrrhiza cultivar Extracts in Breast Cancer Cells

  • Kang, Myunghoon;Kim, Minhee;Kim, Wonnam
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.89-89
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    • 2019
  • Several studies report the anticancer effect of Glycyrrhiza glabra (G. glabra), Glycyrrhiza uralensis (G. uralensis) and their compounds. However, the anticancer effect of Glycyrrhiza cultivar roots are limited. In this study, we compared the anticancer effect of Glycyrrhiza cultivar (Wongam and Shinwongam) extracts with G. glabra and G. uralensis extracts in breast cancer cell lines. Freeze dried Glycyrrhiza root extracts were dissolved in cell culture media at 2 mg/mL and filtered by $0.2{\mu}m$ filter. Glycyrrhiza root extracts were serially diluted at the concentrations of $10{\mu}g/mL$, $100{\mu}g/mL$, $200{\mu}g/mL$, $400{\mu}g/mL$, $800{\mu}g/mL$, $1000{\mu}g/mL$ and $2000{\mu}g/mL$. MCF-7 and MDA-MB-231 breast cancer cells were treated with different concentrations of Glycyrrhiza root extracts and the cell viability was measured using MTT assay. In MCF-7 cells, G. glabra showed no significant difference with Wongam and showed significant difference with Shinwongam at $1000{\mu}g/mL$ (G. glabra 101.2% and Shinwongam 82.68%) and $2000{\mu}g/mL$ (G. glabra 83.07% and Shinwongam 54.05%). G. uralensis showed significant difference with Wongam at $2000{\mu}g/mL$ (G. uralensis 66.48% and Wongam 95.02%) and showed no significant difference with Shinwongam. In MDA-MB-231 cells, G. glabra showed no significant difference with both Wongam and Shinwongam. G. uralensis showed significant difference with Wongam at $2000{\mu}g/mL$ (G. uralensis 72.59% and Wongam 93.47%) and showed no significant difference with Shinwongam. In conclusion, the current study demonstrated that G, glabra and G. uralensis compared with Wongam, and Shinwongam at low concentrations ($10{\mu}g/mL{\sim}800{\mu}g/mL$) display similar cytotoxic potency.

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Detection of Small Flaws in SiC Structural Ceramic in High Frequency Detection Field (고주파수 초음파 검출장에서 SiC 세라믹 내부의 미세결함 검출)

  • Kim, Byoung-Geuk;Lee, S.S.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.17 no.2
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    • pp.100-107
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    • 1997
  • It has been required to find flaws smaller than $100{\mu}m$ by fracture mechanic consideration. We prepared the infiltrated and sintered SiC structural ceramic specimens including artificial flaws, Fe, pore, WC, Si particles of size ranging from $36{\mu}m$ to $200{\mu}m$. We performed C-scan for the specimen using a high frequency and broad-band ultrasonic transducer to employ polyvinylidene fluoride(PVDF) and a broad-band electric scanning system. The flaws in the ceramic specimens were detected in the high frequency detection field up to 100MHz. But, the flaws were not detected in lower frequency detection field up to 60MHz. The ratio of the detected smallest flaw size to the wavelength calculated at the center frequency, 80MHz, was about 0.25 in Rayleigh scattering region.

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Nanoindentation Experiments on MEMS Device (Nanoindenter를 이용한 MEMS 제품의 기계적 특성 측정)

  • 한준희;박준협;김광석;이상율
    • Journal of the Korean Ceramic Society
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    • v.40 no.7
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    • pp.657-661
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    • 2003
  • The elastic moduli or fracture strengths of multi-layered film (SiO$_2$/po1y-Si/SiN/SiO$_2$, 2.77 $\mu\textrm{m}$ thick), CVD diamond film (1.6 $\mu\textrm{m}$ thick), SiO$_2$ film (1.0 $\mu\textrm{m}$ thick) and SiN film (0.43 $\mu\textrm{m}$ thick) made for the membrane of ink-jet printer head were measured with cantilever beam bending method using nanoindenter after fabricating in the form of micro cantilever beam (${\mu}$-CLB). And the elastic moduli of ${\mu}$-CLB of SiO$_2$ film and SiN film were compared with the value of each film on silicon substrate determined with nanoindentation method. The results showed that the modulus and strength of multi-layered film decrease from 68.08 ㎬ and 2.495 ㎬ to 56.53 ㎬ and 1.834 ㎬, respectively as the width of CLB increases from 18.5 $\mu\textrm{m}$ to 58.5 $\mu\textrm{m}$. And the elastic moduli of SiO$_2$ and SiN films measured with ${\mu}$-CLB bending method are 68.16 ㎬ and 215.45 ㎬, respectively and the elastic moduli of these films on silicon substrate measured with nanoindentation method are 98.78 ㎬ and 219.38 ㎬, respectively. These results show that with ${\mu}$-CLB bending technique, moduli can be measured to within 2%.

Optical Design of the Integrated Triplexer Fabricated by Micro Block Stacking Method (MBS 방법으로 제작한 집적형 Triplexer의 광학 설계)

  • Yoon, Hyun-Jae;Kim, Jong-Hyuk
    • Korean Journal of Optics and Photonics
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    • v.22 no.4
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    • pp.191-197
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    • 2011
  • In this paper, we have designed an integrated triplexer which is the basic component for a FTTH(Fiber To The Home) system which can transmit CATV and voice/data at the same time in a single fiber. The integrated triplexer can be fabricated with a novel technique of "Micro-Block Stacking (MBS)" method which automatically aligns the optical components in the optical beam pass using accurate ceramic holders. We analyze the displacement of the optical focus according to the tolerances of the component dimensions and the assembly process using code V simulator. For the transmitter, the most serious shift of the focal points is caused by the displacements of the LD spot. So the focal point moves up to $72{\mu}m$ from the center point for ${\pm}25{\mu}m$, ${\pm}25{\mu}m$, ${\pm}30{\mu}m$ displacements. For the receiver the most serious shift of the focal points is caused by the displacements of a 0.8mm ball lens (for the analog receiving part) and a micro ball lens (for the digital receiving part), and the focal point moves up to $55{\mu}$ for ${\pm}55{\mu}m$, ${\pm}5{\mu}m$, ${\pm}55{\mu}m$ micro ball lens displacements.

Mineral Contents in Bottled Natural Water and Estimation of Their Intake by Korean Adults (일부 무기질의 생수 중 함량 분석과 생수를 통한 섭취량 평가)

  • Kim, Moo-Kyung;Sim, Jin-Ah;Eom, Hee-Jung;Kim, Myung-Hee;Choi, Mi-Kyeong
    • Journal of the Korean Dietetic Association
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    • v.16 no.2
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    • pp.116-121
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    • 2010
  • Minerals play an important role in the body as essential nutrients. However, it is not easy to meet DRIs because food sources of minerals are limited. Recently, consumption of bottled natural water has been increasing in Korea due to water pollution and distrust of tap water. The present study was conducted to investigate mineral contents in bottled natural water and their intakes among Korean adults. We analyzed eight minerals in seven kinds of bottled natural water by ICP-spectrometry and conducted a survey on the intake status of water and bottled natural water with 400 Korean young adults. The mean contents of Ca, Mg, Fe, Zn, Cu, Mn, Se, and Mo in bottled natural water were 22.45${\pm}$22.48 mg/L, 10.59${\pm}$9.97 mg/L, 0.27${\pm}$0.18 ${\mu}g/L$, 2.06${\pm}$1.48 ${\mu}g/L$, 5.47${\pm}$0.70 ${\mu}g/L$, 1.43${\pm}$0.37 ${\mu}g/L$, 1.90${\pm}$0.96 ${\mu}g/L$, and 3.34${\pm}$0.79 ${\mu}g/L$, respectively. The mean age, height, weight, and BMI were 22.76 years, 174.94 cm, 68.64 kg, and 22.41 $kg/m^2$ for males (n=150) and 21.25 years, 162.04 cm, 51.05 kg, and 19.46 $kg/m^2$ for females (n=250), respectively. The respective daily intakes of total water and bottled natural water as water itself were 670.30 ml and 212.20 ml for males and 488.04 ml and 132.72 ml for females. The daily intakes of Ca, Mg, Fe, Zn, Cu, Mn, Se, and Mo from bottled natural water were 4.76 mg, 2.25 mg, 0.06 ${\mu}g$, 0.44 ${\mu}g$, 1.16 ${\mu}g$, 0.30 ${\mu}g$, 0.40 ${\mu}g$, and 0.71 ${\mu}g$ for males and 2.98 ${\mu}g$, 1.41 mg, 0.04 ${\mu}g$, 0.27 ${\mu}g$,0.73 ${\mu}g$, 0.19 ${\mu}g$,0.25 ${\mu}g$, and 0.44 ${\mu}g$ for females, respectively. Overall, the contents of Ca, Mg, and Se in bottled natural water were relatively high and the daily intakes of these minerals were 0.4~1.0% of the DRIs.

A Study on the Shear Bond Strength of the Reinforced Composite Resin to Dental Alloys (강화형 복합레진과 수종의 치과용 합금간의 전단결합강도에 관한 연구)

  • Kim, Jung-Hee;Jo, In-Ho
    • Journal of Dental Rehabilitation and Applied Science
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    • v.16 no.2
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    • pp.113-122
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    • 2000
  • The reinforced composte resin as the esthetic operative material continuously has been studied because the porcelain fused metal prosthesis is widely used for its excellent esthetics, rigidity and marginal integrity, but it has low fracture resistance against the tensile strength and stress, attrition of the opposite teeth. The reinforced composite resin is well adapt with the dental alloy but it is low the shear bond strength with the dental alloy vs the porcelain fused metal prosthesis, and then has been studied continuously. The purpose of the study was to examine how metal was the higher shear bond strength among the dental alloy was used to the reinforced composite resin and to find the effect that the particle size of sandblasting influenced the shear bond strength. We built up the reinforced composite resin with 4 mm in diameter, 3 mm in height on circular alloy with 5 mm in diameter, 2 mm in height. Type II gold, type IV gold, and Ag-Pd alloy was used as alloys and $50{\mu}m$, $110{\mu}m$, $250{\mu}m$ of the particle size was sandblasted at each alloy in bonding between alloy and resin. We made 90 secimens of 10 per each group and we measured the shear bond strength using the Instron($M100EC^{(R)}$, Mecmesin Co., England). The obtained results were as follows : 1. In comparison among each alloys, Ag-Pd alloy had the highest shear bond strength and the shear bond strength was decreased significantly in the sequence of the type II gold and type IV gold(P<0.001). 2. In comparison according to the size of sandblasting particle, (1) In Ag-Pd alloy, shear bond strength was decreased in the sequence of $110{\mu}m$, $250{\mu}m$, $50{\mu}m$ and there were significant difference in all the group. (P<0.05) (2) In type II gold, it was decreased in the sequence of $250{\mu}m$, $50{\mu}m$, $110{\mu}m$ and there were significant difference. (P<0.05) (3) In type IV gold, it was decreased in the sequence of $110{\mu}m$, $50{\mu}m$, $250{\mu}m$. There were significant difference between the group of $110{\mu}m$ and $50{\mu}m$, the group of $110{\mu}m$ and 250, but there were no significant difference in the group of $50{\mu}m$ and $250{\mu}m$. 3. The highest shear bond strength according to the size of sandblasting particle was $110{\mu}m$ in Ag-Pd alloy and type IV gold, $250{\mu}m$ in type II gold.

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Analysis of Benzo[α]pyrene Content in Edible Oils from Korean Market (시중에 유통되는 식용유지 중 benzo[α]pyrene 함량 분석)

  • Nam, Hejung;Seo, Ilwon;Lee, Kyueun;Lee, Songyoung;Shin, Han-Seung
    • Food Engineering Progress
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    • v.13 no.3
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    • pp.211-215
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    • 2009
  • Concentrations of benzo[$\alpha$]pyrene in edible oils from Korean market were evaluated by high performance liquid chromatography. Benzo[$\alpha$]pyrene known of the carcinogenic polycyclic aromatic hydrocarbons(PAHs), has been found at variable concentrations in several foods. This is associated with several factors during the process including contaminated raw materials, exposure of environment, and procedure of process or cooking. The levels of benzo[$\alpha$]pyrene were ranged from 0.5 to 1.4 $\mu$g/kg in virgin olive oil. Benzo[$\alpha$]pyrene contents in refined and virgin olive oil, sesame oil, soybean oil, corn oil, sunflower oil, safflower oil, and processed oil were 0.6-1.0 $\mu$g/kg, 0.9-1.3 $\mu$g/kg, 0.6-3.3 $\mu$g/kg, 0.5-1.1 $\mu$g/kg, 1.2-1.7 $\mu$g/kg, 1.0-2.1 $\mu$g/kg, and 1.0-1.4 $\mu$g/kg, respectively.

Distribution of Magnetic Field Depending on the Current in the μ-turn Coil to Capture Red Blood Cells (적혈구 포획용 미크론 크기 코일에 흐르는 전류의 크기에 따른 자기장 분포 특성)

  • Lee, Won-Hyung;Chung, Hyun-Jun;Kim, Nu-Ri;Park, Ji-Soo;Lee, Sang-Suk;Rhee, Jang-Roh
    • Journal of the Korean Magnetics Society
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    • v.25 no.5
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    • pp.162-168
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    • 2015
  • The ${\mu}$-turn coil having a width of ${\mu}m$ on the GMR-SV (giant magnetoresistance-spin valve) device based on the antiferromagnetic IrMn layer was fabricated by using the optical lithography process. In the case of GMR-SV film and GMR-SV device, the magnetoresistance ratios and the magnetic sensitivities are 4.4%, 2.0%/Oe and 1.6 %, 0.1%/Oe, respectively. In the y-z plane the distribution of magnetic field of GMR-SV device and $10{\mu}$-turns coil which put under the several magnetic bead(MB)s with a diameter of $1{\mu}m$ attached to RBC (red blood cell) was analyzed by the computer simulation using the finite element method. When the AC currents of 20 kHz from 0.1 mA to 10.0 mA flow to the 10 turns ${\mu}$-coil, the magnetic field at the position of $z=0{\mu}m$ at the center of coil was calculated from $30.1{\mu}T$ to $3060{\mu}T$ in proportion to the current. The magnetic field at the position of $z=10{\mu}m$ was decreased to one-sixth of that of $z=0{\mu}m$. It was confirmed that the $10{\mu}$-turn coil having enough magnitude of magnetic field for the capture of RBC is possible to use as a biosensor for the detection of magnetic beads attached to RBC.