• Nuclear Engineering and Technology
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• 제52권2호
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• pp.381-396
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• 2020

Investigations of the commercial aircraft impact effect on nuclear island infrastructures have been drawing extensive attention, and this paper aims to perform the safety assessment of Generation III nuclear power plant (NPP) buildings subjected to typical commercial aircrafts crash. At present Part I, finite element (FE) models establishment and validations for both the aircrafts and NPP buildings are performed. (i) Airbus A320 and A380 aircrafts are selected as the representative medium and large commercial aircrafts, and the corresponding fine FE models including the skin, beam, fuel and etc. are established. By comparing the numerically derived impact force time-histories with the existing published literatures, the rationality of aircrafts models is verified. (ii) Fine FE model of the Chinese Zhejiang Sanao NPP buildings is established, including the detailed structures and reinforcing arrangement of both the containment and auxiliary buildings. (iii) By numerically reproducing the existing 1/7.5 scaled aircraft model impact tests on steel plate reinforced concrete (SC) panels and assessing the impact process and velocity time-history of aircraft model, as well as the damage and the maximum deflection of SC panels, the applicability of the existing three concrete constitutive models (i.e., K&C, Winfrith and CSC) are evaluated and the superiority of Winfrith model for SC panels under deformable missile impact is verified. The present work can provide beneficial reference for the integral aircraft crash analyses and structural damage assessment in the following two parts of this paper.

• Nuclear Engineering and Technology
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• 제52권2호
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• pp.397-416
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• 2020

Investigations of the commercial aircraft impact effect on nuclear island infrastructures have been drawing extensive attention, and this paper aims to perform the safety assessment of Generation III nuclear power plant (NPP) buildings subjected to typical commercial aircrafts crash. At present Part II, based on the verified finite element (FE) models of aircrafts Airbus A320 and A380, as well as the NPP containment and auxiliary buildings in Part I of this paper, the whole collision process is reproduced numerically by adopting the coupled missile-target interaction approach with the finite element code LS-DYNA. The impact induced damage of NPP plant under four impact locations of containment (cylinder, air intake, conical roof and PCS water tank) and two impact locations of auxiliary buildings (exterior wall and roof of spent fuel pool room) are evaluated. Furthermore, by considering the inner structures in the containment and raft foundation of NPP, the structural vibration analyses are conducted under two impact locations (middle height of cylinder, main control room in the auxiliary buildings). It indicates that, within the discussed scenarios, NPP structures can withstand the impact of both two aircrafts, while the functionality of internal equipment on higher floors will be affected to some extent under impact induced vibrations, and A380 aircraft will cause more serious structural damage and vibrations than A320 aircraft. The present work can provide helpful references to assess the safety of the structures and inner equipment of NPP plant under commercial aircraft impact.

• Clinical and Experimental Reproductive Medicine
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• 제26권2호
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• pp.265-269
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• 1999

Thrombocytopenic patients without detectable bound antiplatelet antibody should be diagnosed with idiopathic thrombocytopenic purpura (ITP) if no other cause of their decreased platelet count could be found. More recently the term "autoimmune thrombocytopenic purpura (ATP) has supplanted ITP since the disease is related to the production of autoantibodies against one's own platelets. This entity should not be confused with isoimmune thrombocytopenic purpura (also called alloimmune thrombocytopenic purpura). In this cases maternal antiplatelet antibodies directed against the PLA 1 antigen on the fetal platelets causes severe fetal and neonatal thrombocytopenia in a situation analogous to Rheusus disease. Antibodies to the negatively charged phospholipids, lupus anticoagulant, and anticardiolipin have been linked to adverse pregnancy events. Pregnant women possessing these antibodies have an increased risk of spontaneous abortion, stillbirths, intrauterine fetal growth retardation, preterm birth, and arterial and venous thrombosis. Antiphospholipid antibodies decrease or may even disappear between pregnancies only to recur with increased activity in a subsequent pregnancy and lead to loss. We have experienced a case of antiphospholipid syndrome associated with autoimmune thrombocytopenic purpura in patient with recurrent spontaneous abortion. So we report this case with a brief review of literatures.

• 한국동물학회지
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• 제34권4호
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• pp.571-584
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• 1991

잉어과(Gyprinidae)의 Zocco속 어류 4종과 Candidia속 어류 1종에 대한 종간 유연관계와 종분화 연대측정 및 이들의 지질학적 분포경로를 밝히기 위하여 한국, 일본 및 대만에서 채집된 개체를 대상으로 전기영동법에 의한 유전자 분석을 하였다. 각 종의 지역별(한국, 일본, 대만) 집단간 유전적 유연관계를 분석한 결과 평균 유전적 근연치는 90% 이상이었다. Z. temmincki의 경우 일본집 단들은 한국의 A-type 집단과는 유연관계가 가까왔으나 한국의 B-type과는 유전적 차이가 현저하러다. Z. PlaD여5의 경우 한국집단과 일본집단사이의 유연관계는 S = 0.852였고, 한국집단과 대만집단 사이는 5 = 0.672, 일본집단과 대만집단 사이는 S = 0.751로서 지리적으로 현저한 차이를 업였다. Z. pochycephalus 3개 집단간의 유전적 근인치는 S = 0.963이었고 Candidia borbota 2개 집단간은 S = 0.946이었다. 종간의 유전적 근연환계를 비교한 결과 Candidia borbota와 Z. temmincki사이는 S = 0.608, Z. pluDpus와 1. pachycephalus사이는 S = 0.612였으나, Z. temmincki와 Z. platypus사이는 S = 0.441, Z. temmincki 와 Z. pochycepholus 사이는 S = 0.350이었고, Z. plotpus와 Condfda barbata사이는 S = 0.328로서 이들 사이에는 현저한 유전적 차이가 있었다. 각 종간의 롱분화 연대를 추산한 결과 이들은 약 480만년 전인 Pliocene 초기에 공통 조상종에서 분화하여 Z. temmincki, Candidia borbato group과 Z. plotypus, Z. pochycepholus group으로 분리되었고 약 260만년 전인 Pliocene 후기에 Z. temminc소와 Candidia borbota로 분화되었다고 추산되며 약 80만년 전인 Pleistocene시기에 남 temmincki B-type에서 h-type이 분화되었다짙 여겨진다. 한편 또 다른 한 단opP은 약 230만년 전인 열iocene후기에 대만 지역의 Z. plotypas에서 Z. pochvcepholus가 분화된 후 현재에 이르렀다고 추정된다. Z. platypus는 약150만년 이전인 초기 Pleistocene시기에 대만지역에서 한국 및 일본집단으로 분리되었다고 보며 이들 한국집단과 일본집단은 약 50만년 전 Pleistocene의 Middle기에 고황하 수계를 거쳐 현재의 분포 상황에 이르렀다고 여겨진다. 한편 대. temmin체과의 B-type에서 저온 적응으로 분화되었다고 추측되는 A-type은 약 20만년 전인 Pleistocene의 Riss기에 역시 고황하 수계를 통하여 한국과 일본으로 분포하여 현재에 이르렀다고 사료된다.

• Journal of Communications and Networks
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• 제18권2호
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• pp.218-226
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• 2016

Coordination among users is an inevitable but time-consuming operation in wireless networks. It severely limit the system performance when the data rate is high. We present FC-MAC, a novel MAC protocol that can complete a contention within one contention slot over a joint frequency-code domain. When a node takes part in the contention, it generates randomly a contention vector (CV), which is a binary sequence of length equal to the number of available orthogonal frequency division multiplexing (OFDM) subcarriers. In FC-MAC, different user is assigned with a distinct signature (i.e., PN sequence). A node sends the signature at specific subcarriers and uses the sequence of the ON/OFF states of all subcarriers to indicate the chosen CV. Meanwhile, every node uses the redundant antennas to detect the CVs of other nodes. The node with the minimum CV becomes the winner. The experimental results show that, the collision probability of FC-MAC is as low as 0.05% when the network has 100 nodes. In comparison with IEEE 802.11, contention time is reduced by 50-80% and the throughput gain is up to 200%.

• 한국응용과학기술학회지
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• 제16권3호
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• pp.263-271
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• 1999

We checked the presence of phospholipase $A_2(PLA)_2$ which could split the ester bond at the position 2 in the glycerol backbone of glycerophospholipids, in the cells of hyperthermophiles of Pyrococcus horikoshii and Sulfolobus acidocaldarius. The results obtained are as follows; (1). Pyrococcus horikoshii cells were grown in obligate anaerobic conditions at $95^{\circ}C$ and they needed sulfur as energy source instead of oxygen, while Sulfolobus acidocaldarius species grew well in the aerobic medium (pH 2.5) containing yeast and sucrose at $75^{\circ}C$. (2). Pyrococcus horikoshii cells produced phospholipase $A_2$ in the cell culture media although this species did not show lipase activity at least in the pH range of 1.5 ${\sim}$ 3.5. Sulfolobus acidocaldarius cells produced lipase hydrolyzing triacylglycerols such as triolein, but did not split any kind of phospholipids used as substates. (3). The compound of 1-decanoyl-2-(p-nitrophenylglutaryl) phosphatidylcholine was not suitable for a substrate in this experiment, though frequently used as a subtrate for checking presence of phospholipase $A_2$, for its decomposi-tion in this experiment. The L-${\alpha}$-phosphatidylcholine-${\beta}$-[N-7-nitrobenz-2-oxa-1, 3-diazol]aminohexanoyl-${\gamma}$-hexadecanoyl labelled with a fluorescent material, did not show any migration of acyl chains in the molecule during the reaction with phospholipase $A_2$ under a hot condition. (4). Phospholipase $A_2$ in the cells of Pyrococcus horikoshii, showed the optimum activity at $pH6.7{\sim}7.2$ and $95{\sim}105^{\circ}C$, respectively, and was activated by addition of calcium chloride solution. Andthe phospholipase $A_2$ specifically hydrolyzed glycero-phospholipids such as phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine and phosphatidyl inositol, but could not split phospholipid containing ether bonds in the molecule such as DL -${\alpha}$-phosphatidylcholine-${\beta}$-palmitoyl-${\gamma}$-O-hexadecyl, DL-${\alpha}$-phosphati- dylcholine-${\beta}$- oleoyl-${\gamma}$-O-hexadecyl, DL-phosphatidylcholine-dihexadecyl.

• 대한약침학회지
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• 제15권4호
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• pp.32-41
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• 2012

Objectives: Rehmannia glutinosa pharmacopuncture solution (RGPS) was investigated to determine both its anti-allergic inflammatory effects on mast cells and its detailed mechanism of actions. Methods: We investigated whether RGPS suppress cytokines, enzymes, $Fc{\varepsilon}RI$ expression and $Fc{\varepsilon}RI$-mediated signaling in RBL-2H3 cells stimulated with anti-DNP IgE/DNP-HSA. The suppressive effects of RGPS on the levels of cytokines such as IL-$1{\beta}$, IL-6 and GM-CSF were measured using emzyme-linked immunospecific assay (ELISA). The mRNA expression levels of cytokines, enzymes (HDC2, COX-1, COX-2 and 5LO) and $Fc{\varepsilon}RI$ ${\alpha}{\beta}{\gamma}$ subunits were measured using reverse transcription polymerase chain reaction (RT-PCR) method. The activation of $Fc{\varepsilon}RI$-mediated signaling was examined using Western blot analyses. Results: RGPS suppressed production of proinflammatory cytokines (IL-$1{\beta}$, IL-6, and GM-CSF) in stimulated RBL-2H3 cells significantly (p < 0.05). RGPS also suppressed mRNA expression of inflammatory enzymes (HDC2, COX-1, COX-2, 5LO). In addition, mRNA expression levels of $Fc{\varepsilon}RI{\alpha}$, $Fc{\varepsilon}RI{\beta}$and $Fc{\varepsilon}RI{\gamma}$ were lowered by treatment with RGPS. Finally, RGPS prevented phosphrylation of Lyn, Syk, LAT, Gab2, PLC ${\gamma}1/2$, PI3K, Akt, cPLA2 and $I{\kappa}B{\alpha}$. Conclusions: RGPS effectively suppresses mast cell activations such as degranulation and inflammatory response via down-regulation of the $Fc{\varepsilon}RI$-mediated signaling pathways in IgE/Ag-stimulated mast cells.

• 한국식품과학회지
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• 제48권4호
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• pp.378-383
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• 2016

본 연구에서는 퉁퉁마디 추출물의 용매 분획을 통해 얻은 Fr.H, Fr.E, Fr.EA, Fr.B, 및 Fr.W, 분획의 인간 단핵구 THP-1 세포에 대한 면역조절 활성과 정상 장관계 세포 및 장관계 암세포를 이용하여 면역세포와 장관상피 세포의 상호작용에 미치는 영향을 조사하였다. THP-1 세포는 PMA에 의해 분화가 진행되었으며 분화된 THP-1 세포는 LPS에 의해 활성화되어 COX-2 단백질 발현이 유도 되었다. 퉁퉁마디 분획은 분화된 THP-1 세포에서 COX-2, iNOS, 및 $cPLA_2$ 발현에는 영향을 미치지 않았으나, 분획 중 Fr.E는 LPS에 의해 유도된 COX-2의 발현을 유의적으로 증가시켰다. 분화된 THP-1에서 퉁퉁마디 분획을 처리하여 얻은 배양액은 INT-407 정상 장관계 세포의 성장을 촉진한 반면, HT-29 대장암 세포에는 영향을 미치지 않거나 성장 억제 활성을 나타내었다. THP-1에 LPS를 처리한 배양액은 HT-29 세포의 COX-2 발현을 유도하였으며 이러한 LPS의 효과는 Fr.E의 처리에 의해 억제되었다. 본 연구에서는 면역세포와 장관계 세포 간의 상호작용에 미치는 퉁퉁마디 분획의 영향을 조사하여 이를 통한 면역조절 활성을 나타낼 수 있음을 보였으며, 면역조절 기능성 소재로서의 퉁퉁마디의 이용성 확대를 위한 기본 정보를 제공하고자 하였다.

• 한국미생물·생명공학회지
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• 제31권3호
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• pp.250-256
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• 2003

폴리 젖산의 원료가 되는 젖산은 D-, L의 광학이성질체로 존재하는데 L젖산 폴리머와 라세미 폴리머는 결정성과 녹는점이 다르므로 플라스틱으로서의 만족할 만한 물성을 기대하기 위하여 원료로서 광학적으로 순수한 L-lactic acid가 요구된다. 이를 위하여 한 종류의 이성질체만을 선택적으로 생산하는 젖산균주를 탐색하여 분리함으로써 광학적으로 순수한 산물을 얻을 뿐만 아니라 이러한 발효법에 의한 젖산생산은 자연계에 풍부한 starch나 cellulose, 음식물쓰레기와 같은 재생 가능한 자원을 기질로 사용하여 젖산발효에서 전분의 당화 공정에 필요한 시간과 노력을 최소화하며 젖산 생산에 드는 전체적인 비용을 절감할 수 있다. 전분을 직접 이용하는 것은 젖산균의 일반적인 성질이 아니므로 전분이 풍부한 누룩을 수집하여 직접적으로 전분을 분해하여 젖산발효를 수행하는 균주를 누룩에서 분리하였다. 분리균주는 형태학적, 배양학적,생화학적 특성 및 16s rDNA 분석을 통하여 Enterococcus sp.으로 동정되어 Enterococcus sp. JA-27로 명명하였다. 생육에 따른 L-lactic acid의 최적 생산 조건을 검토한 결과, 최적 배지조건은 탄소원으로 1.5% soluble starch, 질소원으로 3.5% tryptone, 그 외의 다른 조성들은 0.1% $K_2$$HPO_4$, 0.04% $MgSO_4$$.$ $7H_2$O, 0.014% $MnSO_4$ $.$ $4H_2$O, 0.04% $MgSO_4$$.$ $7H_2$O이었고 최적 배양조건은 $30^{\circ}C$, pH 8이었다. 대량생산을 위한 기초자료를 제공하기 위하여 회분배양과 유가배양을 실시하였고, 회분배양이 L-lactic acid의 생산수율(0.134 g, L-lactic acid/g, soluble starch)이 더 높게 나타나 효과적이었다. 7 L 발효조 배양시 pH를 control한 결과, L-lactic acid 생산이 삼각플라스크에 비해 1.5배 더 증가하였다. 배지 중의 젖산을 정제하기 위한 방법으로 이온교환 칼럼크로마토그라피(ion-exchange column chromatography)를 사용하였고 일련의 정제 과정을 통하여 배양액 중의 L-lactic acid 정제 수율은 약 85% 정도로 나타났으며 HPLC로 분석한 결과 99.7%의 순도를 확인할 수 있었다.

• 대한치과보철학회지
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• 제43권6호
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• pp.751-763
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• 2005

Statement of problem. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. The surface quality of the implant depends on the chemical, physical, mechanical and topographical properties of the surface. The different properties will interact with each other and a change in thickness of the oxide layer may also result in a change in surface energy, the surface topography and surface, chemical composition. However, there is limited the comprehensive study with regard to changed surface and biologic behavior of osteoblast by anodization. Purpose of study. The aim of this study was to analyze the characteristics of an oxide layer formed and to evaluate the cellular biologic behaviors on titanium by anodic oxidation (anodization) by cellular proliferation, differentiation, ECM formation and gene expression. And the phospholipase activity was measured on the anodized surface as preliminary study to understand how surface properties of Ti implant are transduced into downstream cellular events. Methods and Materials. The surface of a commercially pure titanium(Grade 2) was modified by anodic oxidation. The group 1 samples had a machined surface and other three experimental specimens were anodized under a constant voltage of 270 V(Group 2), 350 V(Group 3), and 450 V(Group 4). The specimen characteristics were inspected using the following five categories; the surface morphology, the surface roughness, the thickness of oxide layer, the crystallinity, and the chemical composition of the oxide layer. Cell numbers were taken as a marker for cell proliferation. While the expression of alkaline phosphatase and Runx2 (Cbfa1) was used as early differentiation marker for osteoblast. The type I collagen production was determined, which constitutes the main structural protein of the extracellular matrix. Phospholipase $A_2$ and D activity were detected. Results. (1) The anodized titanium had a porous oxide layer, and there was increase in both the size and number of pores with increasing anodizing voltage. (2) With increasing voltage, the surface roughness and thickness of the oxide film increased significantly (p<0.01), the $TiO_2$phase changed from anatase to rutile. During the anodic oxidization, Ca and P ions were more incorporated into the oxide layer. (3) The in vitro cell responses of the specimen were also dependant on the oxidation conditions. With increasing voltage, the ALP activity, type I collagen production, and Cbfa 1 gene expression increased significantly (p<0.01), while the cell proliferation decreased. (4) In preliminary study on the relation of surface property and phospholipase, PLD activity was increased but $PLA_2$ activity did not changed according to applied voltage. Conclusion. The anodized titanium shows improved surface characteristics than the machined titanium. The surface properties acquired by anodization appear to give rise more mature osteoblast characteristics and might result in increased bone growth, and contribute to the achievement of a tight fixation. The precise mechanism of surface property signaling is not known, may be related to phospholipase D.