• Title/Summary/Keyword: Domain interaction

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The Effect of Cobrotoxin on $NF-{\kappa}B$ binding Activity in Raw264.7 cells

  • Yoo, Jae-Ryong;Song, Ho-Sueb
    • Journal of Acupuncture Research
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    • v.22 no.2
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    • pp.133-139
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    • 2005
  • Cobrotoxin, a venom of Vipera lebetina turanica, is a group of basic peptidescomposed of 233 amino acids with six disulfide bonds formed by twelve cysteins. NF-kB is activated by subsequent release of inhibitory IkB and translocation of p50. Since sulfhydryl group is present in kinase domain of p50 subunit of NF-kB, cobrotoxin could modify NF-kB activity by protein-protein interaction. We therefore examined effect of cobrotoxin on NF-kB activities in lipopolysaccharide (LPS) and sodium nitroprusside (SNP)-stimulated Raw 264.7 mouse macrophages. Cobrotoxin suppressed the LPS and SNP-induced release of IkB and p50 translocation resulted in inhibition of DNA binding activity of NF-kB. Inhibition of NF-kB resulted in reduction of the LPS and SNP-induced production of inflammatory mediators NO and PGE2 generation. The inhibitory effect of cobrotoxin on the NF-kB activity were blocked by addition of reducing agents dithiothreitol and glutathione. These results demonstrate that cobrotoxin inhibits activation of NF-kB, and suggest that pico to nanomolar range of cobrotoxin could inhibit the expression of genes in the NF-kB signal pathway.

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Comparison of Seismic Responses of Seismically Isolated NPP Containment Structures using Equivalent Linear- and Nonlinear-Lead-Rubber Bearing Modeling (등가선형 및 비선형 납-고무받침 모델을 이용한 면진된 원전구조물의 지진응답의 비교)

  • Lee, Jin Hi;Song, Jong-Keol
    • Journal of the Earthquake Engineering Society of Korea
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    • v.19 no.1
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    • pp.1-11
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    • 2015
  • In order to perform a soil-isolation-structure interaction analysis of seismically isolated nuclear power plant (NPP) structures, the nonlinear behavior of a seismic isolation system may be converted to an equivalent linear model used in frequency domain analysis. Seismic responses for seismically isolated NPP containment structures subjected to a simple artificial acceleration history and different site class earthquakes are evaluated for the equivalent-linear and nonlinear models that have been applied to lead-rubber bearing (LRB) modeling. It can be observed that the maximum displacements of the equivalent linear model are larger than that of the nonlinear model. From the floor response spectrum analysis for the top of NPP containment structures, it can be observed that the spectral acceleration of an equivalent linear model at about 0.5 Hz frequency is about 2~3 times larger than that of a nonlinear model.

Effects on Nonlinear Ship Motions on Ship Maneuvering in Large Amplitude Waves (비선형 선박운동을 고려한 대파고 파랑 중 조종성능에 대한 연구)

  • Seo, Min-Guk;Kim, Yong-Hwan;Kim, Kyong-Hwan
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.6
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    • pp.516-527
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    • 2011
  • This paper considers a numerical analysis of ship maneuvering performance in the high amplitude incident waves by adopting linear and nonlinear ship motion analysis. A time-domain ship motion program is developed to solve the wave-body interaction problem with the ship slip speed and rotation, and it is coupled with a modular type 4-DOF maneuvering problem. Nonlinear Froude-Krylov and restoring forces are included to consider weakly nonlinear ship motion. The developed method is applied to observe the nonlinear ship motion and planar trajectories in maneuvering test in the presence of incident waves. The comparisons are made for S-175 containership with existing experimental data. The nonlinear computation results show a fair agreement of overall tendency in maneuvering performance. In addition, maneuvering performances with respect to wave slope is predicted and reasonable results are observed.

Amino Acid Structure of Dopamine Transporter Responsible for Cocaine Binding (코카인 결합과 관련된 도파민 수송체의 아미노산 구조)

  • 장미윤;전대준;오동렬;이용성;이상훈
    • YAKHAK HOEJI
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    • v.43 no.6
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    • pp.743-750
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    • 1999
  • Human and bovine dopamine transporters (DAT) demonstrate discrete functional differences in the dopamine (DA) transport and cocaine binding. The functional analyses on the chimeras of human and bovine DAT have revealed that the region from the $133^{rd}{\;}to{\;}186^{th}$ residue(encompassing the $3^{rd}$ trans-membrane domain (TM) is responsible for the substrate transport and cocaine binding. The present studies have been done to find out the specific amino acid(s) which is essential for the binding of cocaine to DAT by interchanging the amino acids in that region between human and bovine DAT. When isoleucine, the $152^{nd}$ residue of chimera B3 (bovine DAT sequence) was transformed back to valine, the human DAT residue at the identical position, the cocaine binding was remarkably recovered to 98% of the human DAT values. In addition, the cocaine binding of the human DAT was decreased by 57% by substituting isoleucine for valine at position 152. When isoleucine at position 152 of the chimera B3 was converted to the other amino acids to provide an possible molecular basis for the functional role of the $152^{nd}$ residue, only the conversion to alanine among acids tested significantly the cocaine by 34%, but these effect were not as much as those by the conversion to valine. In conclusion, valine at position 152 is a crucial amino acid for the interaction of cocaine to the DAT.

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A Survey on the Characteristics of Vulnerable Families in a City (일개 도시 취약 가족의 특성에 관한 조사연구)

  • Choi, Kyung-Won;Lee, In-Sook
    • Research in Community and Public Health Nursing
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    • v.20 no.3
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    • pp.371-380
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    • 2009
  • Purpose: This study aimed at describing the characteristics and nursing needs of vulnerable families in a City. Methods: A total of 427 vulnerable families enrolled in the Visiting Health Care Center in K-gu of S city were investigated in this study. Data were collected using questionnaires for one year from Jan to Dec, 2003, and analysed using mean, standard deviation and $x^2$. Results: Most of the vulnerable families investigated here showed many deficits, especially incomplete family structure (62.8%), financial problem (84.0%), lack of support (55.8%) were prevalent. The score of level of economic status in Family Capability for Self management ($1.95{\pm}0.65$) was lowest, and the score of perception of family problem and health of family members ($2.62{\pm}0.78$) was highest. The four family groups divided according to the total score of family management capability showed significant differences in family interaction, support, and coping domain. The total score of family management capability increased as family functioning-related problems decreased in the vulnerable families. Conclusion: In order to find vulnerable families, and improve their family function, it is required to develop the systematic assesment tools, community supportive systems and nursing interventions for family strength.

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A Study on Behavior Rule Induction Method of Web User Group using 2-tier Clustering (2-계층 클러스터링을 사용한 웹 사용자 그룹의 행동규칙추출방법에 관한 연구)

  • Hwang, Jun-Won;Song, Doo-Heon;Lee, Chang-Hoon
    • The KIPS Transactions:PartD
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    • v.15D no.1
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    • pp.139-146
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    • 2008
  • It is very important to identify useful web user group and induce their behavior pattern in eCRM domain. Inducing user group with a similar inclination, a reliability of user group decreases because there is an uncertainty in online user data. In this paper, we have applied the 2-tier clustering, which uses the outcome of interaction with data from other tiers. Also we propose a method which induces user behavior pattern from a cluster and compare C4.5 with our method.

A Study on Interaction of Estuarial Water and Sediment Transport (하구수와 표사의 상호작용에 관한 연구)

  • Lee, H.;Lee, J.W.
    • Journal of Korean Port Research
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    • v.14 no.4
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    • pp.451-461
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    • 2000
  • The design and maintenance of navigation channel and water facilities of an harbor which is located at the mouth of river or at the estuary area are difficult due to the complexity of estuarial water and sediment circulation. Effects of deepening navigable waterways, of changing coastline configurations, or of discharging dredged material to the open sea are necessary to be investigated and predicted in terms of water quality and possible physical changes to the coastal environment. A borad analysis of the transport mechanism in the estuary area was made in terms of sediment property, falling velocity, concentration and flow characteristics. In order to simulate the transport processes, a two-dimensional finite element model is developed, which includes erosion, transport and deposition mechanism of suspended sediments. Galerkin’s weighted residual method is used to solve the transient convection-diffusion equation. The fluid domain is subdivided into a series of triangular elements in which a quadratic approximation is made for suspended sediment concentration. Model could deal with a continuous aggregation by stipulating the settling velocity of the flocs in each element. The model provides suspended sediment concentration, bed shear stress, erosion versus deposition rate and bed profile at the given time step.

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Cellular Uptake Behavior of Poly(D,L-lactide-co-glycolide) Nanoparticles Derivatized with HIV-1 Tat49-57 Peptide (Abbreviated Title: Tat-PLGA Nanoparticles)

  • Park, Ju-Young;Nam, Yoon-Sung;Kim, Jun-Oh;Han, Sang-Hoon;Chang, Ih-Seop
    • Journal of Pharmaceutical Investigation
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    • v.34 no.2
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    • pp.101-106
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    • 2004
  • This work aims at examining the cellular uptake behavior of poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles derivatized with a protein transduction domain (PTD) using HeLa cells. For this purpose, $Tat_{49-57}$ peptide derived from transcriptional activation (Tat) protein of HIV type-1 was covalently conjugated to the terminal end of PLGA. Nanoparticles were ten prepared with the $Tat_{49-57}-PLGA$ conjugates by a spontaneous phase inversion method. The prepared particles had a mean diameter of ca. 84 nm, as measured by dynamic light scattering. The interaction of the Tat-PLGA nanoparticles with cells was examined by using confocal laser scanning microscopy. It was found tat Tat-PLGA nanoparticles incubated with HeLa cells could efficiently translocate into cytoplasm, while plain PLGA nanoparticles showed negligible cellular uptake. In addition, even at $4^{\circ}C$ or in the presence of sodium azide significant cellular internalization of Tat-PLGA nanoparticles was still observed. These results indicate that a non-endocytotic translocation mechanism might be involved in the cellular uptake of Tat-PLGA nanoparticles.

An Improved Control Method for Power Conversion System under a Weak Grid by the Adoption of Virtual Resistors

  • Gao, Ning;Sang, Shun;Li, Rui;Cai, Xu
    • Journal of Power Electronics
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    • v.17 no.3
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    • pp.756-765
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    • 2017
  • The control of the power conversion system (PCS) in a battery energy storage system has a challenge due to the existence of grid impedance. This paper studies an impedance model of an LCL-based PCS in the d-q domain. The feature of a PCS connected to a weak grid is unveiled by use of an impedance model and a generalized Nyquist criterion. It is shown that the interaction between grid impedance and the PCS destabilizes the cascaded system in certain cases. Therefore, this paper proposes a novel control method that adopts virtual resistors to overcome this issue. The improvement in the control loop leads the PCS to a more stable condition than the conventional method. Impedance measurement is implemented to verify the correctness of the theoretical analysis. Experimental results obtained from a down-scaled prototype indicate that the proposed control method can improve the performance of the PCS under a weak grid.

DEAD/DExH-Box RNA Helicases in Selected Human Parasites

  • Marchat, Laurence A.;Arzola-Rodriguez, Silvia I.;Cruz, Olga Hernandez-de la;Lopez-Rosas, Itzel;Lopez-Camarillo, Cesar
    • Parasites, Hosts and Diseases
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    • v.53 no.5
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    • pp.583-595
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    • 2015
  • DEAD/DExH-box RNA helicases catalyze the folding and remodeling of RNA molecules in prokaryotic and eukaryotic cells, as well as in many viruses. They are characterized by the presence of the helicase domain with conserved motifs that are essential for ATP binding and hydrolysis, RNA interaction, and unwinding activities. Large families of DEAD/DExH-box proteins have been described in different organisms, and their role in all molecular processes involving RNA, from transcriptional regulation to mRNA decay, have been described. This review aims to summarize the current knowledge about DEAD/DExH-box proteins in selected protozoan and nematode parasites of medical importance worldwide, such as Plasmodium falciparum, Leishmania spp., Trypanosoma spp., Giardia lamblia, Entamoeba histolytica, and Brugia malayi. We discuss the functional characterization of several proteins in an attempt to understand better the molecular mechanisms involving RNA in these pathogens. The current data also highlight that DEAD/DExH-box RNA helicases might represent feasible drug targets due to their vital role in parasite growth and development.