• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.1
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• pp.149-156
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• 2017

Graphene nanoplatelet (GNP)-reinforced alumina ($Al_2O_3$) is a promising material for micro-partapplications, particularly micro-nozzle shapes, because of its excellent wearresistance. In this study, a $Al_2O_3$/GNPcomposite with 15 vol% graphene nanoplatelets (GNP) was highly densified and fabricated via spark plasma sintering for micro-electrical discharge drilling (Micro-ED drilling) and the wear resistance property of the composite is evaluated via the ball-on-disk method. In addition, the diameter and shape of the micro-electrodes machined by wire electrical discharge grinding (WEDG), block electrical discharge grinding (BEDG), and new linear block moving electrical discharge grinding (LBMEDG) methods are systematically compared and analyzed to observe the micro-hole machining in the micro-ED drilling of the $Al_2O_3$/15vol% GNP composite.

• Explosives and Blasting
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• v.14 no.2
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• pp.71-80
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• 1996

A series of nurmerical analysse for the earhtquake of Iran railway tunnles under construction by NATM(New Astrian Tunnelling Method) were careid out throuth a pseudo-dynamic analyses techique used in a FFM computer program, DWTAP(Daewoo Tunnel Analysis Program), and the results are described in the paper. The analyses were performErl for two case;one is for the primary supports and the other is for the rompletEd permanent roncrete lining. The horizontal and verical groW1d accelerations for the design were estimatEd as 0.34 g and 0.23 g, respectively based on the historical reismic rerords in the proj3et area and the empirical equations. The results show that the turmel would be safe W1der the anticipitOO earthquake motion with the permanent roncrete lining, but some minor cracks rnigt be developErl in the primary shotcrete lining without any significant structural damages.

• Clinical and Experimental Reproductive Medicine
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• v.1 no.1
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• pp.49-54
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• 1974

In the present studies, effect of progesterone on the germinal vesicle break-down of the mouse oocytes cultured in the micro tube was investigated. The results obtained are as follows: As dose of progesterone in the medium rose, accordingly the break-down of the germinal vesicle was suppressed. It was found that $ED_{50}$ was 15.7 ${\mu}g$/ml, and $ED_{90}$ 60.7 ${\mu}g$/ml of progesterone. The dose suppressing the oocyte maturation was apparently higher than that on the rabbit or on the mouse embryonal development. The inhibiting effect of progesterone on the GVBD was reversible. The germinal vesicle of the oocytes were broken down immediately in the medium upon removal of the hormone. Progesterone stops meiosis at any stage upon administration, while dbe AMP or theophylline supresses only the break-down of the nuclear membrane. Recovering of the meiotic division of the oocytes once exposed to progesterone was delayed a little. The inhibiting action of progesterone was not altered by adding more pyruvate or in the presence of higher concentration of the mineral ions in the culture medium.

• International Journal of Oral Biology
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• v.42 no.1
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• pp.9-15
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• 2017

Microglia have multiple functions in regulating homeostasis of the central nervous system. Microglia cells have been implicated as active contributors to neuron damage in neurodegenerative disorders. In this study, medicinal plant extracts (MPEs) were used to evaluate the cell-death induction effect in microglia BV-2 cells. Among 35 MPEs tested in this study, 4 MPEs showed less than a 30% cell survival after 24 hours of incubation. These were Foeniculi Fructus, Forsythiae Fructus, Zingiberis Rhizoma and Hedera Rhombea. The concentration showed that 50% cell death ($IC_{50}$) occurred with 33, 83, 67 Ed highlight: Please confirm wording, and $81{\mu}/ml$, respectively. For further study, we chose Zingiberis Rhizoma (ZR) which showed a reasonably low $IC_{50}$ value and an induction of cell death in a relatively narrow range. Western blot analysis showed that ZR-treated cells showed activation of caspase-3 and cleavage of PARP Ed highlight: When an acronym is first presented it needs to be spelled out in both dose- and time-dependent manners. However, the level of Bcl-2 and Bax were not changed by ZR-treatment in BV-2 cells. These results suggest that ZR-induced apoptosis in BV-2 cells occured through caspase-3 activation. The results also suggested that ZR may be useful in developing treatments for neurodegenerative diseases.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.4
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• pp.560-565
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• 2013

Biological decontamination means the removal of microorganisms from the inanimate object such as building or equipment. In this study, hydrogen peroxide vapor efficacy test using VHP 1000ED system(Steris LifeSciences) were conducted for G. stearothermophilus spore with agent materials(aluminum, stainless steel, poly-carbonate, viton, silicone, kapton and glass). Total recovered spores exposed to hydrogen peroxide vapor(1.0 g/min) during 7, 15, 30, 60 min were calculated. As a result, all agent materials were totally decontaminated within 60 min at 1.0 g/min concentration with 35% hydrogen peroxide vapor. Finally, we could confirmed that hydrogen peroxide vapor possess sporicidal capacity of G. stearothermophilus and found the optimum decontamination conditions with VHP1000ED system.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.573-582
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• 2006

The perception and attitude of dietitians on processed meats with seasoning were investigated. Questionnaires were distributed to 176 dietitians at school foodservice operations in Kyungnam province. In the survey results, about half (Ed-better to give the exact number of percentage) of the dietitians answered that it is ‘necessary’ to develop processed meats with seasoning. Regarding desired product characteristics, the dietitians were asked about-reduced additive use, good hygienic quality, nutritious and healthy quality, low salt content and adequate supply of nutritional information. Over half of the dietitians-(65.5%) preferred Korean style processed meats with seasoning. The cooking types chosen as new developments for Korean processed meats with seasoning were grilled (36.2%), fried (19.8%), and roasted (18.6%). The dietitians wanted no or only a little increase in the price compared to current commercial products, 1kg (50.6%) size as the package unit and 7 days (45.1%) shelf life under refrigerated or frozen storage.(Ed-confirm the highlighted changes) A majority of the dietitians (64.2%) responded positively to buy the processed meats with seasoning if the products meet their needs.

• Journal of Korean Society of Rural Planning
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• v.25 no.1
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• pp.67-74
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• 2019

This study is to identify the heat vulnerability area as represented by heat risk factors which could be attributable to heat-related deaths. The heat risk factors were temperature, Older Adults(OA), Economic Disadvantage(ED), Accessibility of Medical Services(AMS), The population Single Person Households(SPH). The factors are follow as; the temperature means to the number of days for decades average daily maximum temperature above $31^{\circ}C$, the Older Adults means to population ages 65 and above, furthermore, the Economic Disadvantage means to the population of Basic Livelihood Security Recipients(BLSR), the Accessibility of Medical Services(AMS) means to 5 minutes away from emergency medical services. The results of the analysis are showed that the top-level of temperature vulnerability areas is Dong, the top-level of vulnerability OA areas is Eup, the top-level of AMS vulnerability is Eup. Moreover, the top-level of vulnerability ED area appears in the Eup and Dong. The result of analysing relative importance to each element, most of the Eup were vulnerable to heat. Since, there are many vulnerable groups such as Economic Disadvantage, Older Adults in the Eup. We can be figured out estimated the number of heat-related deaths was high in the Eup and Dong by the data of emergency activation in the Chungcheongnam-do Fire Department. Therefore, the result of this study could be reasonable.

• Korean Journal of Metals and Materials
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• v.47 no.1
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• pp.1-6
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• 2009

Magnesium alloys are drawing a lot of attention and have been extensively studied. The major obstacle to the practical application of the alloys is the poor formability at room temperature, originating basically from the insufficient number of slip system. Development of a proper texture is one promising solution to improve the formability. In the present work, after extrusion and full annealing, microstructures, texture developments and tensile properties of AZ31 Mg alloys are studied. After full annealing strong <1010>||ED fiber texture and weak <1120>+<1230>||ED fiber texture (c-axes in the radial direction) were developed. The textures are distinctly influencing the tensile properties, which can be understood in terms of the activation of basal slip modes. With the random orientation, which is developed in the $45^{\circ}$ sample to the extrusion direction, the better workability can be achieved at room temperature.

• Journal of Embryo Transfer
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• v.32 no.1
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• pp.25-31
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• 2017

This study was conducted to investigate the effect of activation method on the endoplasmic reticulum (ER) stress induction, apoptosis and in vitro development of porcine parthenogenetic embryos. Porcine in vitro matured oocytes were activated by four activation methods; 1) electric stimulus (ES) (E), 2) $ES+10{\mu}M$ Ca-ionophore (A23187) treatment (EC), 3) ES+2 mM 6-dimethylaminopurine (6-DMAP) treatment (ED), or 4) ES+A23187 and 6-DMAP treatments (ECD). Parthenogenetic embryos were sampled to analyze x-box binding protein 1 (Xbp1) mRNA, ER stress-associated genes and apoptosis genes at 3 h after ES and the 1-cell and blastocyst stages. In the EC group, the band intensity of spliced Xbp1 (Xbp1s) mRNA was higher than those of the other groups at the 3 h and 1-cell stage, and higher than that of the E group at the blastocyst stage. Four ER stress-associated genes were expressed at the highest level in the EC group and weakly expressed in the ED group at 3 h after activation. However, most of the genes were highly expressed at the 1-cell and blastocyst stages with some variation in the EC and ECD groups. Expression of Bcl-2-associated X protein (Bax) and caspase-3 mRNA was significantly higher in the EC group than in the other groups at all development stages. The developmental rates to the blastocyst stage were higher in the ED and ECD groups than in the E and EC groups. These results suggest that the intracellular ER stress of parthenogenetic porcine embryos is affected by the activation method and subsequently lead to the apoptosis of embryos.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.198-206
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• 1998

Fourty eight derivatives of 2-(1-oxyalkyl)-1,4-dioxy-9,10-anthraquinone were synthesized, and their antitumor activity was evaluated. On the whole, 2-(1-hydroxyalkyl)-1,4-dihydroxy-9,10-anthraquinones (DHAQ=1,4-dihydroxy-9,10-anthraquinone) showed stronger cytotoxic activity against L1210 cells than 2-(l-hydroxyalkyl)-1,4-dimethoxy-9,10-anthraquinones(DMAQ =1,4-dimethoxy-9,10-anthraquinone), implying that free hydroxy groups at C-1 and C-4 of the anthraquinone structure are necessary for the cytotoxic activity. The bioactivity of 2-(lhydroxyalkyl)-DHAQ derivatives differed according to the size of alkyl group at C-1;while the elongation of alkyl group over 7 carbon atoms failed to enhance the bioactivity, the derivatives possessing alkyl moiety of 1-6 carbon atoms showed an increase in the cytotoxicity and the antitumor activity in Sarcoma-180; 2-hydroxymethyl-DHAQ ($ED_{50}$, $15\mu\textrm{g}$/ml; T/C, 125%), 2-(1 -hydroxyethyl)-DHAQ($1.9{\mu}g/ml;139.2%)$;, 2-(1-hydroxypropyl)-DHAQ ($7.2{\mu}g$/ml; 135.1%), 2-(1-hydroxybutyl)-DHAQ ($10.2{\mu}g/ml; 125.3%)$, 2-(1-hydroxypentyl)-DHAQ ($23.7{\mu}g/ml; 110.1%$). and 2-(1-hydroxyhexyl)-DHAQ ($58{\mu}g/ml;108%$). Next, 2-(1-Hydroxyalkyl)-DHAQ derivatives were acetylated to produce 2-(1-acetoxyalkyl)-DHAQ analogues. Although the acetylation somewhat enhanced the cytotoxicity, but not the antitumor action. In addition, the presence of phenyl group at $C-1^{l}$ enhanced the cytotoxicity and the T/C value, compared to alkyl groups of same size; 2-(1-hydroxy-1-phenyl)-DHAQ ($ED_{50}$, $5.6{\mu}g$, T/C, 137%).