• Title/Summary/Keyword: SRC

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A Computationally Efficient Sphere Decoding Algorithm with Smart Radius Control (스마트 반지름 제어를 사용한 효율적인 구복호 알고리즘)

  • Han, Hee-Goo;Oh, Seong-Keun
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.93-96
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    • 2005
  • We propose a computationally efficient sphere decoding (SD) algorithm with smart radius control (SRC). As a baseline algorithm for SD, we consider the modified Schnorr-Euchner (SE) algorithm [1] (hereafter, called as the MSE algorithm). In principle, the radius after zero-forcing decision feedback equalization (ZF-DFE) estimation can be reduced further if we select a new lattice vector closer to the received signal vector than the lattice vector corresponding to the ZF-DFE estimate does. In our case, we obtain such a better lattice vector by performing a sequence of alternating one-dimensional searches, starting from the ZF-DFE estimate. We then develop a novel SRC algorithm that adopts adaptively the additional radius reduction process according to the estimated signal-to-noise-power ratio (SNR) after ZF-DFE estimation. In addition, we analyze the effect of detection ordering on the complexity for SD. Column-norm ordering of the channel matrix and optimal ordering [1] are considered here. From our analyses, we see that SRC can reduce greatly the complexity for SD and the degree of complexity reduction gets significant as the SNR decreases, irrespective of detection ordering schemes used.

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Beauvericin, a cyclic peptide, inhibits inflammatory responses in macrophages by inhibiting the NF-κB pathway

  • Yoo, Sulgi;Kim, Mi-Yeon;Cho, Jae Youl
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.4
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    • pp.449-456
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    • 2017
  • Beauvericin (BEA), a cyclic hexadepsipeptide produced by the fungus Beauveria bassiana, is known to have anti-cancer, anti-inflammatory, and anti-microbial actions. However, how BEA suppresses macrophage-induced inflammatory responses has not been fully elucidated. In this study, we explored the anti-inflammatory properties of BEA and the underlying molecular mechanisms using lipopolysaccharide (LPS)-treated macrophage-like RAW264.7 cells. Levels of nitric oxide (NO), mRNA levels of transcription factors and the inflammatory genes inducible NO synthase (iNOS) and interleukin (IL)-1, and protein levels of activated intracellular signaling molecules were determined by Griess assay, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), luciferase reporter gene assay, and immunoblotting analysis. BEA dose-dependently blocked the production of NO in LPS-treated RAW264.7 cells without inducing cell cytotoxicity. BEA also prevented LPS-triggered morphological changes. This compound significantly inhibited nuclear translocation of the $NF-{\kappa}B$ subunits p65 and p50. Luciferase reporter gene assays demonstrated that BEA suppresses MyD88-dependent NF-${\kappa}B$ activation. By analyzing upstream signaling events for $NF-{\kappa}B$ activation and overexpressing Src and Syk, these two enzymes were revealed to be targets of BEA. Together, these results suggest that BEA suppresses $NF-{\kappa}B$-dependent inflammatory responses by suppressing both Src and Syk.

Antioxidant Properties of Rajgira (Amaranthus paniculatus) Leaves and Potential Synergy in Chemoprevention

  • Sreelatha, S.;Dinesh, E.;Uma, C.
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2775-2780
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    • 2012
  • In recent years there has been a substantial increase in the use of functional foods for disease control. Fruits and vegetables produce phytochemicals such as flavonoids and antioxidants which can lower oxidative stress and reduce the risk of chronic ailments like cancer. The aim of the present study was to investigate the antioxidant capacity and the possible protective effects of Amaranthus paniculatus leaves on the antioxidant defense system in Ehrlich's ascites carcinoma (EAC)-treated mice. Oral administration of the leaf extract at different doses caused a significant decrease in tumor volume, viable cell count and tumor weight and elevated the life span of EAC bearing mice. It also showed an improved antioxidant potential as evidenced by a significant increase in the cellular antioxidant defense system such as catalase, superoxide dismutase and reduced glutathione and also significantly reduced the levels of TBARS. The levels of RBC, hemoglobin and lymphocyte count were altered in EAC bearing mice and were reverted back to near normal levels after the treatment with the leaf extracts. Their adequate content of total phenolics and flavonoids, DPPH scavenging activity which further suggests that the extracts exert a significant protection against oxidative stress conditions.

Src Protein Tyrosine Kinases in Stress Responses

  • Grishin, Anatoly;Corey, Seth J.
    • Animal cells and systems
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    • v.6 no.1
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    • pp.1-12
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    • 2002
  • A role of Src family protein Tyrosine kinases (SFK) as mediators of receptor-ligand initiated responses is well established. Well documented, but less well understood is the role of SFK in cellular reaction to stresses. Evidence from the wide variety of experimental systems indicates that SFK mediate responses to all major classes of stress, including oxidation, DNA damage, mechanical impacts, and protein denaturing. SFK may be activated by stresses directly or via regulatory circuits whose identity is not yet fully understood. Depending on the cell type and the nature of activating stimulus, SFK may activate known downstream signaling cascades leading to cell survival, proliferation, cytoskeletal rearrangement, and apoptosis; the identity of these cascades is discussed. As in the case of receptor-initiated signaling, roles of individual SFK in various stress response may be redundant or non-redundant. Although signals generated by different stresses are generally transduced via distinct SFK pathways, these pathways may overlap or exhibit crosstalk. In some cell types stress-induced activation of SFK promotes survival and inhibits apoptosis, whereas the opposite may be true for other cell types. Stress responses constitute a new and rapidly developing area of SFK-mediated signaling.

Cancer Prevention Effect of Epigallocatechin-3-gallate through Regulate in C-terminal Src Kinase (CSK) Signaling Pathway (녹차성분 EGCG의 CSK 단백질 조절을 통한 암예방 효과)

  • Kim, Dae Yong;Choi, Bu Young
    • Korean Journal of Pharmacognosy
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    • v.45 no.2
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    • pp.127-134
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    • 2014
  • A great interest is emerging about green tea as a tool against human cancer proliferation or inflammation, as pointed out by recent reports describing the inhibitory action of epigallocatechin gallate (EGCG) on angiogenesis, urokinase, metalloproteinases, and induction of inducible nitric oxide synthase. We proposed that EGCG may regulate a multi target signaling having wider spectra of action than those actions of single enzymes. CSK (c-terminal Src kinase) protein is a non-receptor tyrosine kinase involved in the cross-talk and mediation of many signaling pathways that promote cell proliferation, adhesion, invasion, migration, and tumorigenesis. Based on the knowledge that CSK activation is important for cancer proliferation we hypothesized that CSK could be a target of EGCG. Here we showed that EGCG effectively suppressed the growth of CSK MEF cell when compare with CSK knockout MEF cell growth. These results indicate that EGCG could be used as a chemoprevention to modulate CSK signal pathway in inflammatory processes and tumor formation.

Comparison of Quality Analyses of Domestic and Imported Wheat Flour Products Marketed in Korea (시판 중인 우리밀 및 수입밀 밀가루의 품질 및 특성 비교 분석)

  • Kim, Sang Sook;Chung, Hae Young
    • The Korean Journal of Food And Nutrition
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    • v.27 no.2
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    • pp.287-293
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    • 2014
  • The physicochemical characteristics of 4 domestic wheat flour products were compared to those of 4 imported wheat flour products marketed in Korea. The contents of moisture, ash, protein, total dietary fiber (TDF), color (L, a, b), whiteness, solvent retention capacity (SRC), water absorption index (WAI), water soluble index (WSI), pasting characteristics by rapid visco analyzer (RVA), and principle component analysis (PCA) were analyzed. The domestic wheat flour products were composed of higher content in ash and protein, compared to the imported wheat flour products. The domestic wheat flour products had lower SRC and WSI characteristics than the imported wheat flour products. The values of lactic acid SRC (LASRC) in the imported wheat flour products showed an increasing trend as the protein content increased. The differences in viscosity were observed in the domestic wheat flour products. However, no major significant differences of viscosity were found among the imported wheat flour products. The result of PCA showed a consistent trend in the imported wheat flour (strong, medium, and weak), while a consistent trend was not shown in the domestic wheat flour products. Therefore, further research is needed to standardize the different types of domestic wheat flour products.

Axial load behavior and stability strength of circular tubed steel reinforced concrete (SRC) columns

  • Yan, Biao;Liu, Jiepeng;Zhou, Xuhong
    • Steel and Composite Structures
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    • v.25 no.5
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    • pp.545-556
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    • 2017
  • The tubed steel reinforced concrete (SRC) column is a composite column in which the outer steel tube is mainly used to provide confinement on the core concrete. This paper presents experimental and analytical studies on the behavior of circular tubed SRC (TSRC) columns subjected to axial compression. Eight circular TSRC columns were tested to investigate the effects of length-to-diameter ratio (L/D) of the specimens, diameter-to-thickness ratio (D/t) of the steel tubes, and use of stud shear connectors on the steel sections. Elastic-plastic analysis on the steel tubes was used to investigate the mechanism of confinement on the core concrete. The test results indicated that the tube confinement increased the strength and deformation capacity for both short and slender columns, and the effects on strength were more pronounced for short columns. A nonlinear finite element (FE) model was developed using ABAQUS, in which the nonlinear material behavior and initial geometric imperfection were included. Good agreement was achieved between the predicted results using the FE model and the test results. The test and FE results were compared with the predicted strengths calculated by Eurocode 4 and the AISC Standard. Based on the analytical results, a new design method for this composite column was proposed.

Experimental study on mechanical performances of lattice steel reinforced concrete inner frame with irregular section columns

  • Xue, Jianyang;Gao, Liang;Liu, Zuqiang;Zhao, Hongtie;Chen, Zongping
    • Steel and Composite Structures
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    • v.16 no.3
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    • pp.253-267
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    • 2014
  • Based on the test on a 1/2.5-scaled model of a two-bay and three-story inner frame composed of reinforced concrete beams and lattice steel reinforced concrete (SRC) irregular section columns under low cyclic reversed loading, the failure process and the features of the frame were observed. The subsequence of plastic hinges of the structure, the load-displacement hysteresis loops and the skeleton curve, load bearing capacity, inter-story drift ratio, ductility, energy dissipation and stiffness degradation were analyzed. The results show that the lattice SRC inner frame is a typical strong column-weak beam structure. The hysteresis loops are spindle-shaped, and the stiffness degradation is insignificant. The elastic-plastic inter-story deformation capacity is high. Compared with the reinforced concrete frame with irregular section columns, the ductility and energy dissipation of the structure are better. The conclusions can be referred to for seismic design of this new kind of structure.

Antitumor activities of hypericin as a protein tyrosine kinase blocker

  • Kil, Kwang-Sup;Yum, Young-Na;Seo, Seung-Hoon;Lee, Kyung-Tae
    • Archives of Pharmacal Research
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    • v.19 no.6
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    • pp.490-496
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    • 1996
  • Naphtodianthrone hypericin produced a potent antitumor activity in vitro against several tumor cells. However, it did not show any cytotoxicity on normal cells such as Macaccus rheus monkey kidney cells (MA-104) and primary cultured rat hepatocytes up to $500{\mu}M$ concentration. Hypericin added to A431 human epidermoid carcinoma cell membrane inhibited the autophosphorylation of the epidermal growth factor (EGF) receptor and the tyrosine phosphorylation of RR-SRC peptide catalyzed by an EGF-receptor. Similarly, treatment of the A431 cells with hypericin inhibited the tyrosine phosphorylation of EGF-dependent endogenous EGF-receptor by western blotting analysis. Hypericin also inhibited the T cell PTK, $P56^{lck}$, in a dose-dependent fashion with an $IC_{50}=5{\mu}M$. The tyrosine phosphorylation, on RR-SRC peptide and EGF-induced receptor autophosphorylation, either in vitro or in intact cells was inhibited by hypericin at the same concentration as that in A431 cell proliferation. These data suggest that hypericin directly inhibits EGF-receptor and $P56^{lck}$ PTK activity in vitro and can mediate such action in vivo.

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Finite element modeling of bond-slip performance of section steel reinforced concrete

  • Liu, Biao;Bai, Guo-Liang
    • Computers and Concrete
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    • v.24 no.3
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    • pp.237-247
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    • 2019
  • The key issue for the finite element analysis (FEA) of section steel reinforced concrete (SRC) structure is how to consider the bond-slip performance. However, the bond-slip performance is hardly considered in the FEA of SRC structures because it is difficult to achieve in the finite element (FE) model. To this end, the software developed by Python can automatically add spring elements for the FE model in ABAQUS to considering bond-slip performance. The FE models of the push-out test were conducted by the software and calculated by ABAQUS. Comparing the calculated results with the experimental ones showed that: (1) the FE model of SRC structure with the bond-slip performance can be efficiently and accurately conducted by the software. For the specimen with a length of 1140 mm, 3565 spring elements were added to the FE model in just 6.46s. In addition, different bond-slip performance can also be set on the outer side, the inner side of the flange and the web. (2) The results of the FE analysis were verified against the corresponding experimental results in terms of the law of the occurrence and development of concrete cracks, the stress distribution on steel, concrete and steel bar, and the P-S curve of the loading and free end.