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Sample records for neuregulin heparin-binding domain

  1. Dual chain synthetic heparin-binding growth factor analogs

    Energy Technology Data Exchange (ETDEWEB)

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY

    2012-04-24

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  2. Dual chain synthetic heparin-binding growth factor analogs

    Science.gov (United States)

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY

    2009-10-06

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  3. The heparin-binding domain of HB-EGF mediates localization to sites of cell-cell contact and prevents HB-EGF proteolytic release

    Energy Technology Data Exchange (ETDEWEB)

    Prince, Robin N.; Schreiter, Eric R.; Zou, Peng; Wiley, H. S.; Ting, Alice Y.; Lee, Richard T.; Lauffenburger, Douglas A.

    2010-07-01

    Heparin-binding EGF-like growth factor (HB-EGF) is a ligand for EGF receptor (EGFR) and possesses the ability to signal in juxtacrine, autocrine and/or paracrine mode, with these alternatives being governed by the degree of proteolytic release of the ligand. Although the spatial range of diffusion of released HB-EGF is restricted by binding heparan-sulfate proteoglycans (HSPGs) in the extracellular matrix and/or cellular glycocalyx, ascertaining mechanisms governing non-released HB-EGF localization is also important for understanding its effects. We have employed a new method for independently tracking the localization of the extracellular EGFlike domain of HB-EGF and the cytoplasmic C-terminus. A striking observation was the absence of the HB-EGF transmembrane proform from the leading edge of COS-7 cells in a wound-closure assay; instead, this protein localized in regions of cell-cell contact. A battery of detailed experiments found that this localization derives from a trans interaction between extracellular HSPGs and the HBEGF heparin-binding domain, and that disruption of this interaction leads to increased release of soluble ligand and a switch in cell phenotype from juxtacrine-induced growth inhibition to autocrine-induced proliferation. Our results indicate that extracellular HSPGs serve to sequester the transmembrane pro-form of HB-EGF at the point of cell-cell contact, and that this plays a role in governing the balance between juxtacrine versus autocrine and paracrine signaling.

  4. Structural Characterization of the E2 Domain of APL-1, a C. Elegans Homolog of Human Amyloid Precursor Protein, and its Heparin Binding Site

    Energy Technology Data Exchange (ETDEWEB)

    Hoopes, J.; Liu, X; Xu, X; Demeler, B; Folta-Stogniew, E; Li, C; Ha, Y

    2010-01-01

    The amyloid {beta}-peptide deposit found in the brain tissue of patients with Alzheimer disease is derived from a large heparin-binding protein precursor APP. The biological function of APP and its homologs is not precisely known. Here we report the x-ray structure of the E2 domain of APL-1, an APP homolog in Caenorhabditis elegans, and compare it to the human APP structure. We also describe the structure of APL-1 E2 in complex with sucrose octasulfate, a highly negatively charged disaccharide, which reveals an unexpected binding pocket between the two halves of E2. Based on the crystal structure, we are able to map, using site-directed mutagenesis, a surface groove on E2 to which heparin may bind. Our biochemical data also indicate that the affinity of E2 for heparin is influenced by pH: at pH 5, the binding appears to be much stronger than that at neutral pH. This property is likely caused by histidine residues in the vicinity of the mapped heparin binding site and could be important for the proposed adhesive function of APL-1.

  5. The heparin-binding site in tetranectin is located in the N-terminal region and binding does not involve the carbohydrate recognition domain

    DEFF Research Database (Denmark)

    Lorentsen, R H; Graversen, Jonas Heilskov; Caterer, N R

    2000-01-01

    Tetranectin is a homotrimeric plasma and extracellular-matrix protein that binds plasminogen and complex sulphated polysaccharides including heparin. In terms of primary and tertiary structure, tetranectin is related to the collectin family of Ca(2+)-binding C-type lectins. Tetranectin is encoded...... in three exons. Exon 3 encodes the carbohydrate recognition domain, which binds to kringle 4 in plasminogen at low levels of Ca(2+). Exon 2 encodes an alpha-helix, which is necessary and sufficient to govern the trimerization of tetranectin by assembling into a triple-helical coiled-coil structural element....... Here we show that the heparin-binding site in tetranectin resides not in the carbohydrate recognition domain but within the N-terminal region, comprising the 16 amino acid residues encoded by exon 1. In particular, the lysine residues in the decapeptide segment KPKKIVNAKK (tetranectin residues 6...

  6. The heparin-binding domain of HB-EGF mediates localization to sites of cell-cell contact and prevents HB-EGF proteolytic release

    Science.gov (United States)

    Prince, Robin N.; Schreiter, Eric R.; Zou, Peng; Wiley, H. Steven; Ting, Alice Y.; Lee, Richard T.; Lauffenburger, Douglas A.

    2010-01-01

    Heparin-binding EGF-like growth factor (HB-EGF) is a ligand for EGF receptor (EGFR) and possesses the ability to signal in juxtacrine, autocrine and/or paracrine mode, with these alternatives being governed by the degree of proteolytic release of the ligand. Although the spatial range of diffusion of released HB-EGF is restricted by binding heparan-sulfate proteoglycans (HSPGs) in the extracellular matrix and/or cellular glycocalyx, ascertaining mechanisms governing non-released HB-EGF localization is also important for understanding its effects. We have employed a new method for independently tracking the localization of the extracellular EGF-like domain of HB-EGF and the cytoplasmic C-terminus. A striking observation was the absence of the HB-EGF transmembrane pro-form from the leading edge of COS-7 cells in a wound-closure assay; instead, this protein localized in regions of cell-cell contact. A battery of detailed experiments found that this localization derives from a trans interaction between extracellular HSPGs and the HB-EGF heparin-binding domain, and that disruption of this interaction leads to increased release of soluble ligand and a switch in cell phenotype from juxtacrine-induced growth inhibition to autocrine-induced proliferation. Our results indicate that extracellular HSPGs serve to sequester the transmembrane pro-form of HB-EGF at the point of cell-cell contact, and that this plays a role in governing the balance between juxtacrine versus autocrine and paracrine signaling. PMID:20530570

  7. Prevention of adverse events of interferon γ gene therapy by gene delivery of interferon γ-heparin-binding domain fusion protein in mice

    Directory of Open Access Journals (Sweden)

    Mitsuru Ando

    2014-01-01

    Full Text Available Sustained gene delivery of interferon (IFN γ can be an effective treatment, but our previous study showed high levels of IFNγ-induced adverse events, including the loss of body weight. These unwanted events could be reduced by target-specific delivery of IFNγ after in vivo gene transfer. To achieve this, we selected the heparin-binding domain (HBD of extracellular superoxide dismutase as a molecule to anchor IFNγ to the cell surface. We designed three IFNγ derivatives, IFNγ-HBD1, IFNγ-HBD2, and IFNγ-HBD3, each of which had 1, 2, or 3 HBDs, respectively. Each plasmid-encoding fusion proteins was delivered to the liver, a model target in this study, by hydrodynamic tail vein injection. The serum concentration of IFNγ-HBD2 and IFNγ-HBD3 after gene delivery was lower than that of IFNγ or IFNγ-HBD1. Gene delivery of IFNγ-HBD2, but not of IFNγ-HBD3, effectively increased the mRNA expression of IFNγ-inducible genes in the liver, suggesting liver-specific distribution of IFNγ-HBD2. Gene delivery of IFNγ-HBD2-suppressed tumor growth in the liver as efficiently as that of IFNγ with much less symptoms of adverse effects. These results indicate that the adverse events of IFNγ gene transfer can be prevented by gene delivery of IFNγ-HBD2, a fusion protein with high cell surface affinity.

  8. Crystallographic Analysis of Calcium-dependent Heparin Binding to Annexin A2

    Energy Technology Data Exchange (ETDEWEB)

    Shao,C.; Zhang, F.; Kemp, M.; Lindhardt, R.; Waisman, D.; Head, J.; Seaton, B.

    2006-01-01

    Annexin A2 and heparin bind to one another with high affinity and in a calcium-dependent manner, an interaction that may play a role in mediating fibrinolysis. In this study, three heparin-derived oligosaccharides of different lengths were co-crystallized with annexin A2 to elucidate the structural basis of the interaction. Crystal structures were obtained at high resolution for uncomplexed annexin A2 and three complexes of heparin oligosaccharides bound to annexin A2. The common heparin-binding site is situated at the convex face of domain IV of annexin A2. At this site, annexin A2 binds up to five sugar residues from the nonreducing end of the oligosaccharide. Unlike most heparin-binding consensus patterns, heparin binding at this site does not rely on arrays of basic residues; instead, main-chain and side-chain nitrogen atoms and two calcium ions play important roles in the binding. Especially significant is a novel calcium-binding site that forms upon heparin binding. Two sugar residues of the heparin derivatives provide oxygen ligands for this calcium ion. Comparison of all four structures shows that heparin binding does not elicit a significant conformational change in annexin A2. Finally, surface plasmon resonance measurements were made for binding interactions between annexin A2 and heparin polysaccharide in solution at pH 7.4 or 5.0. The combined data provide a clear basis for the calcium dependence of heparin binding to annexin A2.

  9. Latent transforming growth factor β-binding protein-3 and fibulin-1C interact with the extracellular domain of the heparin-binding EGF-like growth factor precursor

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    Eidels Leon

    2002-01-01

    Full Text Available Abstract Background The membrane-bound cell-surface precursor and soluble forms of heparin-binding epidermal growth factor-like growth factor (HB-EGF contribute to many cellular developmental processes. The widespread occurrence of HB-EGF in cell and tissue types has led to observations of its role in such cellular and tissue events as tumor formation, cell migration, extracellular matrix formation, wound healing, and cell adherence. Several studies have reported the involvement of such extracellular matrix proteins as latent transforming growth factor β-binding protein, TGF-β, and fibulin-1 in some of these processes. To determine whether HB-EGF interacts with extracellular matrix proteins we used the extracellular domain of proHB-EGF in a yeast two-hybrid system to screen a monkey kidney cDNA library. cDNA clones containing nucleotide sequences encoding domains of two proteins were obtained and their derived amino acid sequences were evaluated. Results From ≈ 3 × 106 screened monkey cDNA clones, cDNA clones were recovered that contained nucleotide sequences encoding domains of the monkey latent transforming growth factor-β binding protein-3 (MkLTBP-3 and fibulin-1C protein. The amino acid sequence derived from the MkLTBP-3 gene shared 98.6% identity with human LTBP-3 and 86.7% identity with mouse LTBP-3 amino acid sequences. The amino acid sequence derived from the monkey fibulin-1C gene shared 97.2% identity with human fibulin-1C. Yeast two-hybrid screens indicate that LTBP-3 and fibulin-1C interact with proHB-EGF through their calcium-binding EGF-like modules. Conclusions The interactions of the extracellular domain of proHB-EGF with LTBP-3 and fibulin-1C suggest novel functions for HB-EGF between cell and tissue surfaces.

  10. Mapping the heparin-binding site of the osteoinductive protein NELL1 by site-directed mutagenesis.

    Science.gov (United States)

    Takahashi, Kaneyoshi; Imai, Arisa; Iijima, Masumi; Yoshimoto, Nobuo; Maturana, Andrés D; Kuroda, Shun'ichi; Niimi, Tomoaki

    2015-12-21

    Neural epidermal growth factor-like (NEL)-like 1 (NELL1) is a secretory osteogenic protein comprising an N-terminal thrombospondin-1-like (TSPN) domain, four von Willebrand factor type C domains, and six epidermal growth factor-like repeats. NELL1 shows heparin-binding activity; however, the biological significance remains to be explored. In this report, we demonstrate that NELL1 binds to cell surface proteoglycans through its TSPN domain. Major heparin-binding sites were identified on the three-dimensional structural model of the TSPN domain of NELL1. Mutant analysis of the heparin-binding sites indicated that the heparin-binding activity of the TSPN domain is involved in interaction of NELL1 with cell surface proteoglycans. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  11. The cell-penetrating peptide domain from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) has anti-inflammatory activity in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jue-Yeon; Seo, Yoo-Na; Park, Hyun-Jung [Research Center, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Park, Yoon-Jeong, E-mail: parkyj@snu.ac.kr [Research Center, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Department of Dental Regenerative Biotechnology, Dental Research Institute and School of Dentistry, Seoul National University, Seoul (Korea, Republic of); Chung, Chong-Pyoung, E-mail: ccpperio@snu.ac.kr [Research Center, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Department of Periodontology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2012-03-23

    Highlights: Black-Right-Pointing-Pointer HBP sequence identified from HB-EGF has cell penetration activity. Black-Right-Pointing-Pointer HBP inhibits the NF-{kappa}B dependent inflammatory responses. Black-Right-Pointing-Pointer HBP directly blocks phosphorylation and degradation of I{kappa}B{alpha}. Black-Right-Pointing-Pointer HBP inhibits nuclear translocation of NF-{kappa}B p65 subunit. -- Abstract: A heparin-binding peptide (HBP) sequence from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) was identified and was shown to exhibit cell penetration activity. This cell penetration induced an anti-inflammatory reaction in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. HBP penetrated the cell membrane during the 10 min treatment and reduced the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cytokines (TNF-{alpha} and IL-6) in a concentration-dependent manner. Additionally, HBP inhibited the LPS-induced upregulation of cytokines, including TNF-{alpha} and IL-6, and decreased the interstitial infiltration of polymorphonuclear leukocytes in a lung inflammation model. HBP inhibited NF-{kappa}B-dependent inflammatory responses by directly blocking the phosphorylation and degradation of I{kappa}B{alpha} and by subsequently inhibiting the nuclear translocation of the p65 subunit of NF-{kappa}B. Taken together, this novel HBP may be potentially useful candidate for anti-inflammatory treatments and can be combined with other drugs of interest to transport attached molecules into cells.

  12. Distinct neurobehavioural effects of cannabidiol in transmembrane domain neuregulin 1 mutant mice.

    Directory of Open Access Journals (Sweden)

    Leonora E Long

    Full Text Available The cannabis constituent cannabidiol (CBD possesses anxiolytic and antipsychotic properties. We have previously shown that transmembrane domain neuregulin 1 mutant (Nrg1 TM HET mice display altered neurobehavioural responses to the main psychoactive constituent of cannabis, Δ(9-tetrahydrocannabinol. Here we investigated whether Nrg1 TM HET mice respond differently to CBD and whether CBD reverses schizophrenia-related phenotypes expressed by these mice. Adult male Nrg1 TM HET and wild type-like littermates (WT received vehicle or CBD (1, 50 or 100 mg/kg i.p. for 21 days. During treatment and 48 h after withdrawal we measured behaviour, whole blood CBD concentrations and autoradiographic receptor binding. Nrg1 HET mice displayed locomotor hyperactivity, PPI deficits and reduced 5-HT(2A receptor binding density in the substantia nigra, but these phenotypes were not reversed by CBD. However, long-term CBD (50 and 100 mg/kg selectively enhanced social interaction in Nrg1 TM HET mice. Furthermore, acute CBD (100 mg/kg selectively increased PPI in Nrg1 TM HET mice, although tolerance to this effect was manifest upon repeated CBD administration. Long-term CBD (50 mg/kg also selectively increased GABA(A receptor binding in the granular retrosplenial cortex in Nrg1 TM HET mice and reduced 5-HT(2A binding in the substantia nigra in WT mice. Nrg1 appears necessary for CBD-induced anxiolysis since only WT mice developed decreased anxiety-related behaviour with repeated CBD treatment. Altered pharmacokinetics in mutant mice could not explain our findings since no genotype differences existed in CBD blood concentrations. Here we demonstrate that Nrg1 modulates acute and long-term neurobehavioural effects of CBD, which does not reverse the schizophrenia-relevant phenotypes.

  13. Proteomic analysis of egg white heparin-binding proteins: towards the identification of natural antibacterial molecules.

    Science.gov (United States)

    Guyot, Nicolas; Labas, Valérie; Harichaux, Grégoire; Chessé, Magali; Poirier, Jean-Claude; Nys, Yves; Réhault-Godbert, Sophie

    2016-06-13

    The chicken egg resists most environmental microbes suggesting that it potentially contains efficient antimicrobial molecules. Considering that some heparin-binding proteins in mammals are antibacterial, we investigated the presence and the antimicrobial activity of heparin-binding proteins from chicken egg white. Mass spectrometry analysis of the proteins recovered after heparin-affinity chromatography, revealed 20 proteins, including known antimicrobial proteins (avidin, lysozyme, TENP, ovalbumin-related protein X and avian bêta-defensin 11). The antibacterial activity of three new egg candidates (vitelline membrane outer layer protein 1, beta-microseminoprotein-like (LOC101750704) and pleiotrophin) was demonstrated against Listeria monocytogenes and/or Salmonella enterica Enteritidis. We showed that all these molecules share the property to inhibit bacterial growth through their heparin-binding domains. However, vitelline membrane outer layer 1 has additional specific structural features that can contribute to its antimicrobial potential. Moreover, we identified potential supplementary effectors of innate immunity including mucin 5B, E-selectin ligand 1, whey acidic protein 3, peptidyl prolyl isomerase B and retinoic acid receptor responder protein 2. These data support the concept of using heparin affinity combined to mass spectrometry to obtain an overview of the various effectors of innate immunity composing biological milieus, and to identify novel antimicrobial candidates of interest in the race for alternatives to antibiotics.

  14. Proteomic analysis of heparin-binding proteins from human seminal ...

    Indian Academy of Sciences (India)

    Heparin-binding proteins (HBPs) are essential constituents of human seminal fluid, which bind to sperm lipids containing the phosphorylcholine group and mediate the fertilization process. We utilized a proteomic set-up consisting of affinity chromatography, isoelectric focusing (IEF) coupled with matrix-assisted laser ...

  15. Neuregulin: First Steps Towards a Structure

    Science.gov (United States)

    Ferree, D. S.; Malone, C. C.; Karr, L. J.

    2003-01-01

    Neuregulins are growth factor domain proteins with diverse bioactivities, such as cell proliferation, receptor binding, and differentiation. Neureguh- 1 binds to two members of the ErbB class I tyrosine kinase receptors, ErbB3 and ErbB4. A number of human cancers overexpress the ErbB receptors, and neuregulin can modulate the growth of certain cancer types. Neuregulin-1 has been shown to promote the migration of invasive gliomas of the central nervous system. Neuregulin has also been implicated in schizophrenia, multiple sclerosis and abortive cardiac abnormalities. The full function of neuregulin-1 is not known. In this study we are inserting a cDNA clone obtained from American Type Culture Collection into E.coli expression vectors to express neuregulin- 1 protein. Metal chelate affinity chromatography is used for recombinant protein purification. Crystallization screening will proceed for X-ray diffraction studies following expression, optimization, and protein purification. In spite of medical and scholarly interest in the neuregulins, there are currently no high-resolution structures available for these proteins. Here we present the first steps toward attaining a high-resolution structure of neuregulin- 1, which will help enable us to better understand its function

  16. N-tert-butyloxycarbonyl-Phe-Leu-Phe-Leu-Phe (BOC2) inhibits the angiogenic activity of heparin-binding growth factors.

    Science.gov (United States)

    Nawaz, Imtiaz M; Chiodelli, Paola; Rezzola, Sara; Paganini, Giuseppe; Corsini, Michela; Lodola, Alessio; Di Ianni, Alessio; Mor, Marco; Presta, Marco

    2018-02-01

    The peptides N-tert-butyloxycarbonyl-Phe-Leu-Phe-Leu-Phe (BOC2) and BOC-Met-Leu-Phe (BOC1) are widely used antagonists of formyl peptide receptors (FPRs), BOC2 acting as an FPR1/FPR2 antagonist whereas BOC1 inhibits FPR1 only. Extensive investigations have been performed by using these FPR antagonists as a tool to assess the role of FPRs in physiological and pathological conditions. Based on previous observations from our laboratory, we assessed the possibility that BOC2 may exert also a direct inhibitory effect on the angiogenic activity of vascular endothelial growth factor-A (VEGF-A). Our data demonstrate that BOC2, but not BOC1, inhibits the angiogenic activity of heparin-binding VEGF-A 165 with no effect on the activity of the non-heparin-binding VEGF-A 121 isoform. Endothelial cell-based bioassays, surface plasmon resonance analysis, and computer modeling indicate that BOC2 may interact with the heparin-binding domain of VEGF-A 165 , thus competing for heparin interaction and preventing the binding of VEGF-A 165 to tyrosine kinase receptor VEGFR2, its phosphorylation and downstream signaling. In addition, BOC2 inhibits the interaction of a variety of heparin-binding angiogenic growth factors with heparin, including fibroblast growth factor 2 (FGF2) whose angiogenic activity is blocked by the compound. Accordingly, BOC2 suppresses the angiogenic potential of human tumor cell lines that co-express VEGF-A and FGF2. Thus, BOC2 appears to act as a novel multi-heparin-binding growth factor antagonist. These findings caution about the interpretation of FPR-focusing experimental data obtained with this compound and set the basis for the design of novel BOC2-derived, FPR independent multi-target angiogenesis inhibitors.

  17. Effectively enhancing cytotoxic and apoptotic effects of alpha-momorcharin by integrating a heparin-binding peptide.

    Science.gov (United States)

    Tan, Meng-Jie; Cao, Xue-Wei; Li, Peng-Fei; Zhai, Yi-Zhou; Zhou, Yu; Liu, Ye-Jun; Zhao, Jian; Wang, Fu-Jun

    2017-11-01

    Alpha-momorcharin (α-MMC), a type I ribosome-inactivating protein, has attracted a great deal of attention because of its antitumor activity. However, the cytotoxicity of α-MMC is limited due to insufficient cellular internalization in cancer cells. To enhance the cytotoxicity of α-MMC, a heparin-binding domain derived from heparin-binding epidermal growth factor (named heparin-binding peptide [HBP]) was used as a cell-penetrating peptide and fused to the C-terminus of α-MMC. This novel α-MMC-HBP fusion protein was expressed and purified with a Ni 2+ -resin. The N-glycosidase activity and DNase activity assay indicated that the introduction of HBP did not interfere with the intrinsic bioactivities of α-MMC. HBP was able to efficiently carry α-MMC into the tested cancer cells and significantly enhance the cytotoxic effects of α-MMC in a dose-dependent manner. This enhanced cytotoxic ability occurred due to the higher level of cell apoptosis induced by α-MMC-HBP, which was demonstrated in western blot analysis in which α-MMC-HBP triggered caspase 8, caspase 9, casapase 3, and PARP more intensely than α-MMC alone. α-MMC-HBP led to an upregulation of cleaved PARP and an increase in the Bax/Bcl-2 ratio. Our study provided a new practical way to greatly improve the antitumor activity of α-MMC, which could significantly expand the pharmaceutical applications of α-MMC. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

  18. Cell adhesion to fibrillin-1: identification of an Arg-Gly-Asp-dependent synergy region and a heparin-binding site that regulates focal adhesion formation

    DEFF Research Database (Denmark)

    Bax, Daniel V; Mahalingam, Yashithra; Cain, Stuart

    2007-01-01

    We have defined the molecular basis of cell adhesion to fibrillin-1, the major structural component of extracellular microfibrils that are associated with elastic fibres. Using human dermal fibroblasts, and recombinant domain swap fragments containing the Arg-Gly-Asp motif, we have demonstrated a......, and confirmed their role in focal adhesion formation. These integrin and syndecan adhesion motifs juxtaposed on fibrillin-1 are evolutionarily conserved and reminiscent of similar functional elements on fibronectin, highlighting their crucial functional importance....... a requirement for upstream domains for integrin-alpha(5)beta(1)-mediated cell adhesion and migration. An adjacent heparin-binding site, which supports focal adhesion formation, was mapped to the fibrillin-1 TB5 motif. Site-directed mutagenesis revealed two arginine residues that are crucial for heparin binding...

  19. Proteomic analysis of egg white heparin-binding proteins: towards the identification of natural antibacterial molecules

    OpenAIRE

    Guyot, Nicolas; Labas, Valérie; Harichaux, Grégoire; Chessé, Magali; Poirier, Jean-Claude; Nys, Yves; Rehault-Godbert, Sophie

    2016-01-01

    The chicken egg resists most environmental microbes suggesting that it potentially contains efficient antimicrobial molecules. Considering that some heparin-binding proteins in mammals are antibacterial, we investigated the presence and the antimicrobial activity of heparin-binding proteins from chicken egg white. Mass spectrometry analysis of the proteins recovered after heparin-affinity chromatography, revealed 20 proteins, including known antimicrobial proteins (avidin, lysozyme, TENP, ova...

  20. Heparin Binds Lamprey Angiotensinogen and Promotes Thrombin Inhibition through a Template Mechanism.

    Science.gov (United States)

    Wei, Hudie; Cai, Haiyan; Wu, Jiawei; Wei, Zhenquan; Zhang, Fei; Huang, Xin; Ma, Lina; Feng, Lingling; Zhang, Ruoxi; Wang, Yunjie; Ragg, Hermann; Zheng, Ying; Zhou, Aiwu

    2016-11-25

    Lamprey angiotensinogen (l-ANT) is a hormone carrier in the regulation of blood pressure, but it is also a heparin-dependent thrombin inhibitor in lamprey blood coagulation system. The detailed mechanisms on how angiotensin is carried by l-ANT and how heparin binds l-ANT and mediates thrombin inhibition are unclear. Here we have solved the crystal structure of cleaved l-ANT at 2.7 Å resolution and characterized its properties in heparin binding and protease inhibition. The structure reveals that l-ANT has a conserved serpin fold with a labile N-terminal angiotensin peptide and undergoes a typical stressed-to-relaxed conformational change when the reactive center loop is cleaved. Heparin binds l-ANT tightly with a dissociation constant of ∼10 nm involving ∼8 monosaccharides and ∼6 ionic interactions. The heparin binding site is located in an extensive positively charged surface area around helix D involving residues Lys-148, Lys-151, Arg-155, and Arg-380. Although l-ANT by itself is a poor thrombin inhibitor with a second order rate constant of 500 m(-1) s(-1), its interaction with thrombin is accelerated 90-fold by high molecular weight heparin following a bell-shaped dose-dependent curve. Short heparin chains of 6-20 monosaccharide units are insufficient to promote thrombin inhibition. Furthermore, an l-ANT mutant with the P1 Ile mutated to Arg inhibits thrombin nearly 1500-fold faster than the wild type, which is further accelerated by high molecular weight heparin. Taken together, these results suggest that heparin binds l-ANT at a conserved heparin binding site around helix D and promotes the interaction between l-ANT and thrombin through a template mechanism conserved in vertebrates. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Distinct phenotypes of new transmembrane-domain neuregulin 1 mutant mice and the rescue effects of valproate on the observed schizophrenia-related cognitive deficits.

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    Ju-Chun ePei

    2014-04-01

    Full Text Available Accumulating evidence suggests that neuregulin 1 (NRG1 might be involved in the neurodevelopment, neural plasticity, GABAergic neurotransmission and pathogenesis of schizophrenia. NRG1 is abundantly expressed in the hippocampus, and emerging studies have begun to reveal the link between NRG1 signaling and cognitive deficits in schizophrenic patients. Because the transmembrane domain of NRG1 is vital for both forward and reverse signaling cascades, new Nrg1-deficient mice that carry a truncation of the transmembrane domain of the Nrg1 gene were characterized and used in this study to test a NRG1 loss-of-function hypothesis for schizophrenia. Both male and female Nrg1 heterozygous mutant mice and their wild-type littermates were used in a series of 4 experiments to characterize the impact of Nrg1 on behavioral phenotypes and to determine the importance of Nrg1 in the regulation of hippocampal neuromorphology and local GABAergic interneurons. First, a comprehensive battery of behavioral tasks indicated that male Nrg1-deficient mice exhibited significant impairments in cognitive functions. Second, pharmacological challenges were conducted and revealed that Nrg1 haploinsufficiency altered GABAergic activity in males. Third, although no genotype-specific neuromorphological alterations were found in the hippocampal CA1 pyramidal neurons, significant reductions in the hippocampal expressions of GAD67 and parvalbumin were revealed in the Nrg1-deficient males. Fourth, chronic treatment with valproate rescued the observed behavioral deficits and hippocampal GAD67 reduction in Nrg1-deficient males. Collectively, these results indicate the potential therapeutic effect of valproate and the importance of Nrg1 in the regulation of cognitive functions and hippocampal GABAergic interneurons, especially in males.

  2. Shape-persistent and adaptive multivalency: rigid transgeden (TGD) and flexible PAMAM dendrimers for heparin binding.

    Science.gov (United States)

    Bromfield, Stephen M; Posocco, Paola; Fermeglia, Maurizio; Tolosa, Juan; Herreros-López, Ana; Pricl, Sabrina; Rodríguez-López, Julián; Smith, David K

    2014-07-28

    This study investigates transgeden (TGD) dendrimers (polyamidoamine (PAMAM)-type dendrimers modified with rigid polyphenylenevinylene (PPV) cores) and compares their heparin-binding ability with commercially available PAMAM dendrimers. Although the peripheral ligands are near-identical between the two dendrimer families, their heparin binding is very different. At low generation (G1), TGD outperforms PAMAM, but at higher generation (G2 and G3), the PAMAMs are better. Heparin binding also depends strongly on the dendrimer/heparin ratio. We explain these effects using multiscale modelling. TGD dendrimers exhibit "shape-persistent multivalency"; the rigidity means that small clusters of surface amines are locally well optimised for target binding, but it prevents the overall nanoscale structure from rearranging to maximise its contacts with a single heparin chain. Conversely, PAMAM dendrimers exhibit "adaptive multivalency"; the flexibility means individual surface ligands are not so well optimised locally to bind heparin chains, but the nanostructure can adapt more easily and maximise its binding contacts. As such, this study exemplifies important new paradigms in multivalent biomolecular recognition. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Enhanced levels of Hsulf-1 interfere with heparin-binding growth factor signaling in pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Giese Nathalia A

    2005-04-01

    Full Text Available Abstract Hsulf-1 is a newly identified enzyme, which has the ability to decrease the growth of hepatocellular, ovarian, and head and neck squamous cell carcinoma cells by interfering with heparin-binding growth factor signaling. Since pancreatic cancers over-express a number of heparin-binding growth factors and their receptors, the expression and function of this enzyme in pancreatic cancer was analyzed. Results Pancreatic cancer samples expressed significantly (22.5-fold increased Hsulf-1 mRNA levels compared to normal controls, and Hsulf-1 mRNA was localized in the cancer cells themselves as well as in peritumoral fibroblasts. 4 out of 8 examined pancreatic cancer cell lines expressed Hsulf-1, whereas its expression was below the level of detection in the other cell lines. Stable transfection of the Hsulf-1 negative Panc-1 pancreatic cancer cell line with a full length Hsulf-1 expression vector resulted in increased sulfatase activity and decreased cell-surface heparan-sulfate proteoglycan (HSPG sulfation. Hsulf-1 expression reduced both anchorage-dependent and -independent cell growth and decreased FGF-2 mediated cell growth and invasion in this cell line. Conclusion High expression of Hsulf-1 occurs in the stromal elements as well as in the tumor cells in pancreatic cancer and interferes with heparin-binding growth factor signaling.

  4. Characterizations of heparin-binding proteins in human urine by affinity purification-mass spectrometry and defining "L-x(2,3)-A-x(0,1)-L" as a novel heparin-binding motif.

    Science.gov (United States)

    Manissorn, Juthatip; Thongboonkerd, Visith

    2016-06-16

    Heparin-binding proteins (HBPs) are considered as potential modulators of kidney stone formation. However, HBPs had not been characterized in the urine previously. In this study, we applied affinity purification-mass spectrometry (AP-MS) using cellufine sulfate column chromatography and liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-Q-TOF MS/MS) to identify HBPs in normal human urine. Using this approach, 83 HBPs were identified, including those involved in metabolic process, cellular process, immune system, developmental process, response to stimuli, cell communication, transport, cell adhesion and others. The AP-MS data were confirmed by Western blot analysis and chemico-protein interactions analysis using STITCH tool. In addition, 59, 55 and 51 identified HBPs had the known heparin-binding motifs "XBBXnBX", "XBXnBBX" and "XBBBnX", respectively. Moreover, a novel heparin-binding motif "L-x(2,3)-A-x(0,1)-L" was found in 58 identified HBPs using PRATT tool. The sensitivity and specificity of this novel motif were 85% and 100%, respectively, by validation using 20 known HBPs and 11 non-HBPs. We report herein for the first time a large number of HBPs in normal human urine and defined "L-x(2,3)-A-x(0,1)-L" as a novel heparin-binding motif. These findings will be useful to further understand the renal physiology and may also lead to identification of novel modulators of kidney stone formation. Heparin-binding proteins (HBPs) have several important roles in various biological processes, including kidney stone formation. However, HBPs had not been characterized in the urine. Our present work using affinity purification coupled to mass spectrometry (AP-MS) is the first large-scale study on HBPs in human urine. In addition to the three known heparin-binding motifs, "XBBXnBX", "XBXnBBX", and "XBBBnX", we successfully defined the amino acid pattern "L-x(2,3)-A-x(0,1)-L" as a novel heparin-binding motif. These findings will be useful to further

  5. Dimerisation and structural integrity of Heparin Binding Hemagglutinin A from Mycobacterium tuberculosis: implications for bacterial agglutination.

    Science.gov (United States)

    Esposito, Carla; Carullo, Paola; Pedone, Emilia; Graziano, Giuseppe; Del Vecchio, Pompea; Berisio, Rita

    2010-03-19

    Heparin Binding Hemagglutinin A (HBHA) is hitherto the sole virulence factor associated with tuberculosis dissemination from the lungs, the site of primary infection, to epithelial cells. We have previously reported the solution structure of HBHA, a dimeric and elongated molecule. Since oligomerisation of HBHA is associated with its ability to induce bacterial agglutination, we investigated this process using experimental and modelling techniques. We here identified a short segment of HBHA whose presence is mandatory for the stability of folded conformation, whose denaturation is a reversible two-state process. Our data suggest that agglutination-driven cell-cell interactions do not occur via association of HBHA monomers, nor via association of HBHA dimers and open the scenario to a possible trans-dimerisation process. Copyright 2010 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  6. Epidermal transformation leads to increased perlecan synthesis with heparin-binding-growth-factor affinity

    DEFF Research Database (Denmark)

    Tapanadechopone, P; Tumova, S; Jiang, X

    2001-01-01

    cells was significantly increased in both mRNA and protein levels. JB6 perlecan was exclusively substituted with heparan sulphate, whereas that of RT101 contained some additional chondroitin sulphate. Detailed structural analysis of the heparan sulphate (HS) chains from perlecan of both cell types...... revealed that their overall sulphation and chain length were similar (approximately 60 kDa), but the HS chains of tumour-cell-derived perlecan were less sulphated. This resulted from reduced 2-O- and 6-O-sulphation, but not N-sulphation, and an increase in the proportion of unsulphated disaccharides....... Despite this, the heparan sulphate of RT101- and JB6-derived perlecan bound fibroblast growth factor-1, -2, -4 and -7 and heparin-binding epidermal growth factor with similar affinity. Therefore abundant tumour-derived perlecan may support the angiogenic responses seen in vivo and be a key player...

  7. Novel Feature of Mycobacterium avium subsp. paratuberculosis, Highlighted by Characterization of the Heparin-Binding Hemagglutinin Adhesin

    Science.gov (United States)

    Lefrancois, Louise H.; Bodier, Christelle C.; Cochard, Thierry; Canepa, Sylvie; Raze, Dominique; Lanotte, Philippe; Sevilla, Iker A.; Stevenson, Karen; Behr, Marcel A.; Locht, Camille

    2013-01-01

    Mycobacterium avium subsp. paratuberculosis comprises two genotypically defined groups, known as the cattle (C) and sheep (S) groups. Recent studies have reported phenotypic differences between M. avium subsp. paratuberculosis groups C and S, including growth rates, infectivity for macrophages, and iron metabolism. In this study, we investigated the genotypes and biological properties of the virulence factor heparin-binding hemagglutinin adhesin (HBHA) for both groups. In Mycobacterium tuberculosis, HBHA is a major adhesin involved in mycobacterium-host interactions and extrapulmonary dissemination of infection. To investigate HBHA in M. avium subsp. paratuberculosis, we studied hbhA polymorphisms by fragment analysis using the GeneMapper technology across a large collection of isolates genotyped by mycobacterial interspersed repetitive-unit–variable-number tandem-repeat (MIRU-VNTR) and IS900 restriction fragment length polymorphism (RFLP-IS900) analyses. Furthermore, we analyzed the structure-function relationships of recombinant HBHA proteins of types C and S by heparin-Sepharose chromatography and surface plasmon resonance (SPR) analyses. In silico analysis revealed two forms of HBHA, corresponding to the prototype genomes for the C and S types of M. avium subsp. paratuberculosis. This observation was confirmed using GeneMapper on 85 M. avium subsp. paratuberculosis strains, including 67 strains of type C and 18 strains of type S. We found that HBHAs from all type C strains contain a short C-terminal domain, while those of type S present a long C-terminal domain, similar to that produced by Mycobacterium avium subsp. avium. The purification of recombinant HBHA from M. avium subsp. paratuberculosis of both types by heparin-Sepharose chromatography highlighted a correlation between their affinities for heparin and the lengths of their C-terminal domains, which was confirmed by SPR analysis. Thus, types C and S of M. avium subsp. paratuberculosis may be

  8. Heparin-binding protein (HBP): an early marker of respiratory failure after trauma?

    Science.gov (United States)

    Johansson, J; Brattström, O; Sjöberg, F; Lindbom, L; Herwald, H; Weitzberg, E; Oldner, A

    2013-05-01

    Trauma and its complications contribute to morbidity and mortality in the general population. Trauma victims are susceptible to acute respiratory distress syndrome (ARDS) and sepsis. Polymorphonuclear leucocytes (PMNs) are activated after trauma and there is substantial evidence of their involvement in the development of ARDS. Activated PMNs release heparin-binding protein (HBP), a granule protein previously shown to be involved in acute inflammatory reactions. We hypothesised that there is an increase in plasma HBP content after trauma and that the increased levels are related to the severity of the trauma or later development of severe sepsis and organ failure (ARDS). We investigated HBP in plasma samples within 36 h from trauma in 47 patients admitted to a level one trauma centre with a mean injury severity score (ISS) of 26 (21-34). ISS, admission sequential organ failure assessment (SOFA) and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were recorded at admission. ARDS and presence of severe sepsis were determined daily during intensive care. We found no correlation between individual maximal plasma HBP levels at admission and ISS, admission SOFA or APACHE II. We found, however, a correlation between HBP levels and development of ARDS (P = 0.026, n = 47), but not to severe sepsis. HBP is a potential biomarker candidate for early detection of ARDS development after trauma. Further research is required to confirm a casual relationship between plasma HBP and the development of ARDS. © 2013 The Acta Anaesthesiologica Scandinavica Foundation.

  9. Mycobacterial heparin-binding haemagglutinin adhesion-induced interferon & antibody for detection of tuberculosis.

    Science.gov (United States)

    Sun, Zhaogang; Nie, Lihui; Zhang, Xuxia; Li, Yan; Li, Chuanyou

    2011-04-01

    Mycobacterial heparin-binding haemagglutinin adhesin (HBHA) plays an important role in humoral and cellular immune response and is a potential diagnostic tool for tuberculosis (TB) serodiagnosis. This study was carried out to assess the usefulness of HBHA in TB clinics for differential diagnosis of pulmonary and extra-pulmonary TB (PTB, EPTB). In this study, 165 outpatients and 133 healthy volunteers were included to investigate the role of HBHA in TB diagnosis including the serodiagnostic tests and the interferon-γ release assays (IGRAs). The healthy volunteers were all without BCG vaccination including 73 subjects with purified protein derivative (PPD) (-) and 60 ones with PPD (+) (that is P-B- and P+B-). Of all the 165 outpatients 77 were PTB and 88 were EPTB. HBHA protein was used for serodiagnostic tests and IGRAs in peripheral blood mononuclear cells. HBHA-specific antibody levels in the serum of healthy subjects were significantly different from the patients with PTB or EPTB (PEPTB with limited sensitivity (77.08%; 95%CI, 62.69 to 87.97%) and specificity (87.50%; 95%CI, 74.75 to 95.27%). IFN-γ levels in the healthy (P+B- and P-B-) groups were significantly different (PEPTB subjects showed no difference in IFN-γ production. HBHA serodiagnostic test with IGRAs had the limited potential for use as auxiliary tools for the differential diagnosis of PTB and EPTB, since both methods showed low sensitivity and specificity.

  10. Generation and characterization of conditional heparin-binding EGF-like growth factor knockout mice.

    Directory of Open Access Journals (Sweden)

    Atsushi Oyagi

    Full Text Available Recently, neurotrophic factors and cytokines have been shown to be associated in psychiatric disorders, such as schizophrenia, bipolar disorder, and depression. Heparin-binding epidermal growth factor-like growth factor (HB-EGF is a member of the EGF family, serves as a neurotrophic molecular and plays a significant role in the brain. We generated mice in which HB-EGF activity is disrupted specifically in the ventral forebrain. These knockout mice showed (a behavioral abnormalities similar to those described in psychiatric disorders, which were ameliorated by typical or atypical antipsychotics, (b altered dopamine and serotonin levels in the brain, (c decreases in spine density in neurons of the prefrontal cortex, (d reductions in the protein levels of the NR1 subunit of the N-methyl-D-aspartate (NMDA receptor and post-synaptic protein-95 (PSD-95, (e decreases in the EGF receptor, and in the calcium/calmodulin-dependent protein kinase II (CaMK II signal cascade. These results suggest the alterations affecting HB-EGF signaling could comprise a contributing factor in psychiatric disorder.

  11. Heparin-binding proteins of human seminal plasma: purification and characterization.

    Science.gov (United States)

    Kumar, Vijay; Hassan, Md Imtaiyaz; Kashav, Tara; Singh, Tej P; Yadav, Savita

    2008-12-01

    Human seminal plasma (HuSP) contains several proteins that bind heparin and related glycosaminoglycans. Heparin binding proteins (HBPs) from seminal plasma have been shown to participate in modulation of capacitation or acrosome reaction and thus have been correlated with fertility in some species. However, these have not been studied in detail in human. The objective of this study was to purify major HBPs from HuSP in order to characterize these proteins. HBPs were isolated by affinity-chromatography on Heparin-Sepharose column, purified by reverse-phase high-performance liquid chromatography (RP-HPLC) and Size-exclusion chromatography and checked for purity on sodium-dodecyl PAGE (SDS-PAGE). Identification of HBPs was done by matrix-assisted laser desorption-ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). Here we report the purification and identification of seven HBPs in seminal fluid. The major HBPs are lactoferrin and its fragments, semenogelin I fragments, semenogelin II, prostate specific antigen, homolog of bovine seminal plasma-proteins (BSP), zinc finger protein (Znf 169) and fibronectin fragments. In this study we are reporting for the first time the purification and identification of BSP-homolog and Znf 169 from HuSP and classified them as HBPs. Here we report the purification of seven clinically important proteins from human seminal fluid through heparin affinity chromatography and RP-HPLC, in limited steps with higher yield. (c) 2008 Wiley-Liss, Inc.

  12. Heparin-binding-hemagglutinin-induced IFN-gamma release as a diagnostic tool for latent tuberculosis.

    Directory of Open Access Journals (Sweden)

    Jean-Michel Hougardy

    Full Text Available BACKGROUND: The detection of latent tuberculosis infection (LTBI is a major component of tuberculosis (TB control strategies. In addition to the tuberculosis skin test (TST, novel blood tests, based on in vitro release of IFN-gamma in response to Mycobacterium tuberculosis-specific antigens ESAT-6 and CFP-10 (IGRAs, are used for TB diagnosis. However, neither IGRAs nor the TST can separate acute TB from LTBI, and there is concern that responses in IGRAs may decline with time after infection. We have therefore evaluated the potential of the novel antigen heparin-binding hemagglutinin (HBHA for in vitro detection of LTBI. METHODOLOGY AND PRINCIPAL FINDINGS: HBHA was compared to purified protein derivative (PPD and ESAT-6 in IGRAs on lymphocytes drawn from 205 individuals living in Belgium, a country with low TB prevalence, where BCG vaccination is not routinely used. Among these subjects, 89 had active TB, 65 had LTBI, based on well-standardized TST reactions and 51 were negative controls. HBHA was significantly more sensitive than ESAT-6 and more specific than PPD for the detection of LTBI. PPD-based tests yielded 90.00% sensitivity and 70.00% specificity for the detection of LTBI, whereas the sensitivity and specificity for the ESAT-6-based tests were 40.74% and 90.91%, and those for the HBHA-based tests were 92.06% and 93.88%, respectively. The QuantiFERON-TB Gold In-Tube (QFT-IT test applied on 20 LTBI subjects yielded 50% sensitivity. The HBHA IGRA was not influenced by prior BCG vaccination, and, in contrast to the QFT-IT test, remote (>2 years infections were detected as well as recent (<2 years infections by the HBHA-specific test. CONCLUSIONS: The use of ESAT-6- and CFP-10-based IGRAs may underestimate the incidence of LTBI, whereas the use of HBHA may combine the operational advantages of IGRAs with high sensitivity and specificity for latent infection.

  13. Comparative study of heparin-binding proteins profile of Murrah buffalo (Bubalus bubalis semen

    Directory of Open Access Journals (Sweden)

    S. S. Ramteke

    2014-09-01

    Full Text Available Aim: The experiment was conducted to study the total seminal plasma protein (TSPP and heparin-binding proteins (HBPs in relation to initial semen quality of buffalo bull. Materials and Methods: Semen from two Murrah buffalo bulls (bull no. 605 and 790 with mass motility of ≥3+ were used for the study and categorized into three groups (Group I- Mass motility 3+, Group II- Mass motility 4+ and Group III- Mass motility 5+. Seminal plasma from semen was separated by centrifugation. HBPs was isolated and purified from heparin-agarose affinity column by modified elution buffer. TSPP and isolated HBPs concentration was estimated by Lowry’s method. The purified HBPs were resolved on Sodium dodecyl sulfate polyacrylamide gel electrophoresis to check the protein profile of two bulls. Results: The mean values of TSPP concentrations in bull no. 605 and 790 in Group I, II and III were 30.64±0.12, 31.66±0.09, 32.53±0.19 and 28.51±0.09, 29.49±0.15, 30.45±0.17 mg/mL, respectively. The mean values of HBPs concentrations in bull no. 605 and 790 in Group I, II and III were 3.11±0.07, 3.32±0.06, 3.46±0.08 and 2.51±0.08, 2.91±0.05, 3.10±0.03 mg/mL, respectively. Both the values of TSPP and HBPs were significantly higher (p<0.01 in bull no. 605 when compared to 790 in all the three groups. 31 kDa HBP was more intensely present in bull no. 605, thus may indicate its superiority over bull no. 790 in relation to fertility potential. Conclusion: TSPP and HBPs shows variation in concentration with respect to initial semen quality. Furthermore, presence of fertility related 31 kDa HBPs in one of the bull may be an indication of high fertility of a bull. In future, in-vivo and in-vitro correlative study on larger basis is needed for the establishment of fertility-related HBPs in semen which might establish criteria for selection of buffalo bull with high fertility potential.

  14. Single Amino Acid Changes Can Influence Titer, Heparin Binding, and Tissue Tropism in Different Adeno-Associated Virus Serotypes▿

    OpenAIRE

    Wu, Zhijian; Asokan, Aravind; Joshua C Grieger; Govindasamy, Lakshmanan; Agbandje-McKenna, Mavis; Samulski, R. Jude

    2006-01-01

    Despite the high degree of sequence homology between adeno-associated virus (AAV) serotype 1 and 6 capsids (99.2%), these viruses have different liver transduction profiles when tested as vectors. Examination of the six amino acid residues that differ between AAV1 and AAV6 revealed that a lysine-to-glutamate change (K531E) suppresses the heparin binding ability of AAV6. In addition, the same mutation in AAV6 reduces transgene expression to levels similar to those achieved with AAV1 in HepG2 c...

  15. Heparin-binding correlates with increased efficiency of AAV1- and AAV6-mediated transduction of striated muscle, but negatively impacts CNS transduction.

    Science.gov (United States)

    Arnett, A L H; Beutler, L R; Quintana, A; Allen, J; Finn, E; Palmiter, R D; Chamberlain, J S

    2013-05-01

    Gene delivery vectors derived from adeno-associated virus (AAV) have great potential as therapeutic agents. rAAV1 and rAAV6, efficiently target striated muscle, but the mechanisms that determine their tropism remain unclear. It is known that AAV6, but not AAV1, interacts with heparin-sulfate proteoglycans (HSPG). HSPGs are not primary receptors for AAV6, but heparin interactions may affect tissue tropism and transduction. To investigate these possibilities, we generated rAAV1 and rAAV6 capsids that do or do not bind heparin. We evaluated the transduction profile of these vectors in vivo across multiple routes of administration, and found that heparin-binding capability influences tissue transduction in striated muscle and neuronal tissues. Heparin-binding capsids transduce striated muscle more efficiently than non-binding capsids, via both intramuscular and intravenous injection. However, rAAV6 achieved greater muscle transduction than the heparin-binding rAAV1 variant, suggesting that there are additional factors that influence differences in transduction efficiency between AAV1 and AAV6. Interestingly, the opposite trend was found when vectors were delivered via intracranial injection. Non-binding vectors achieved robust and widespread gene expression, whereas transduction via heparin-binding serotypes was substantially reduced. These data indicate that heparin-binding capability is an important determinant of transduction that should be considered in the design of rAAV-mediated gene therapies.

  16. Identification of the heparin binding site on adeno-associated virus serotype 3B (AAV-3B)

    Energy Technology Data Exchange (ETDEWEB)

    Lerch, Thomas F.; Chapman, Michael S. (Oregon HSU)

    2012-05-24

    Adeno-associated virus is a promising vector for gene therapy. In the current study, the binding site on AAV serotype 3B for the heparan sulfate proteoglycan (HSPG) receptor has been characterized. X-ray diffraction identified a disaccharide binding site at the most positively charged region on the virus surface. The contributions of basic amino acids at this and other sites were characterized using site-directed mutagenesis. Both heparin and cell binding are correlated to positive charge at the disaccharide binding site, and transduction is significantly decreased in AAV-3B vectors mutated at this site to reduce heparin binding. While the receptor attachment sites of AAV-3B and AAV-2 are both in the general vicinity of the viral spikes, the exact amino acids that participate in electrostatic interactions are distinct. Diversity in the mechanisms of cell attachment by AAV serotypes will be an important consideration for the rational design of improved gene therapy vectors.

  17. Identification of the heparin binding site on adeno-associated virus serotype 3B (AAV-3B)

    Energy Technology Data Exchange (ETDEWEB)

    Lerch, Thomas F.; Chapman, Michael S., E-mail: chapmami@ohsu.edu

    2012-02-05

    Adeno-associated virus is a promising vector for gene therapy. In the current study, the binding site on AAV serotype 3B for the heparan sulfate proteoglycan (HSPG) receptor has been characterized. X-ray diffraction identified a disaccharide binding site at the most positively charged region on the virus surface. The contributions of basic amino acids at this and other sites were characterized using site-directed mutagenesis. Both heparin and cell binding are correlated to positive charge at the disaccharide binding site, and transduction is significantly decreased in AAV-3B vectors mutated at this site to reduce heparin binding. While the receptor attachment sites of AAV-3B and AAV-2 are both in the general vicinity of the viral spikes, the exact amino acids that participate in electrostatic interactions are distinct. Diversity in the mechanisms of cell attachment by AAV serotypes will be an important consideration for the rational design of improved gene therapy vectors.

  18. Single amino acid changes can influence titer, heparin binding, and tissue tropism in different adeno-associated virus serotypes.

    Science.gov (United States)

    Wu, Zhijian; Asokan, Aravind; Grieger, Joshua C; Govindasamy, Lakshmanan; Agbandje-McKenna, Mavis; Samulski, R Jude

    2006-11-01

    Despite the high degree of sequence homology between adeno-associated virus (AAV) serotype 1 and 6 capsids (99.2%), these viruses have different liver transduction profiles when tested as vectors. Examination of the six amino acid residues that differ between AAV1 and AAV6 revealed that a lysine-to-glutamate change (K531E) suppresses the heparin binding ability of AAV6. In addition, the same mutation in AAV6 reduces transgene expression to levels similar to those achieved with AAV1 in HepG2 cells in vitro and in mouse liver following portal vein administration. In corollary, the converse E531K mutation in AAV1 imparts heparin binding ability and increases transduction efficiency. Extraction of vector genomes from liver tissue suggests that the lysine 531 residue assists in preferential transduction of parenchymal cells by AAV6 vectors in comparison with AAV1. Lysine 531 is unique to AAV6 among other known AAV serotypes and is located in a basic cluster near the spikes that surround the icosahedral threefold axes of the AAV capsid. Similar to studies with autonomous parvoviruses, this study describes the first example of single amino acid changes that can explain differential phenotypes such as viral titer, receptor binding, and tissue tropism exhibited by closely related AAV serotypes. In particular, a single lysine residue appears to provide the critical minimum charged surface required for interacting with heparin through electrostatic interaction and simultaneously plays an unrelated yet critical role in the liver tropism of AAV6 vectors.

  19. Epitope Mapping of a Monoclonal Antibody Directed against Neisserial Heparin Binding Antigen Using Next Generation Sequencing of Antigen-Specific Libraries.

    Directory of Open Access Journals (Sweden)

    Maria Domina

    Full Text Available We explore here the potential of a newly described technology, which is named PROFILER and is based on next generation sequencing of gene-specific lambda phage-displayed libraries, to rapidly and accurately map monoclonal antibody (mAb epitopes. For this purpose, we used a novel mAb (designated 31E10/E7 directed against Neisserial Heparin-Binding Antigen (NHBA, a component of the anti-group B meningococcus Bexsero® vaccine. An NHBA phage-displayed library was affinity-selected with mAb 31E10/E7, followed by massive sequencing of the inserts present in antibody-selected phage pools. Insert analysis identified an amino acid stretch (D91-A128 in the N-terminal domain, which was shared by all of the mAb-enriched fragments. Moreover, a recombinant fragment encompassing this sequence could recapitulate the immunoreactivity of the entire NHBA molecule against mAb 31E10/E7. These results were confirmed using a panel of overlapping recombinant fragments derived from the NHBA vaccine variant and a set of chemically synthetized peptides covering the 10 most frequent antigenic variants. Furthermore, hydrogen-deuterium exchange mass-spectrometry analysis of the NHBA-mAb 31E10/E7 complex was also compatible with mapping of the epitope to the D91-A128 region. Collectively, these results indicate that the PROFILER technology can reliably identify epitope-containing antigenic fragments and requires considerably less work, time and reagents than other epitope mapping methods.

  20. Affinity chromatography, two-dimensional electrophoresis, adapted immunodepletion and mass spectrometry used for detection of porcine and piscine heparin-binding human plasma proteins.

    Science.gov (United States)

    Bjarnadóttir, Stefanía Guðrún; Flengsrud, Ragnar

    2014-01-01

    Heparin-binding proteins in human plasma were studied using affinity chromatography columns with porcine (2mL, 10.7mg capacity) and piscine heparin (5mL, 2.7mg capacity). Two-dimensional electrophoresis (Bio-Rad Protean II gel system with 16cm×16cm gels using isoelectric focusing (IEF) and nonequilibrium pH-gradient gel electrophoresis (NEPHGE)), Bruker Ultraflex MALDI-TOF mass spectrometry and immunoblotting (NovaBlot semidry discontinuous blotting) were used for unfractionated plasma. This revealed electropherograms with differences between porcine and piscine heparin-binding and totally 17 different fibrinogen variants from all 3 chains. Immunodepletion was used to remove fibrinogen (42.1mg anti-human fibrinogen in 8.4mL resin) and serum albumin (0.42mg binding capacity in 14mL resin) and porcine and piscine heparin-binding proteins were identified using liquid chromatography-mass spectrometry (Ultimate 3000 NanoLC with Acclaim PepMap 100 column (50cm×75μm)-LTQ Orbitrap Mass XL). In total, the binding of 76 putative or acknowledged biomarkers are shown. Of the identified proteins, 14 are not previously shown to be heparin-binding, such as the low concentration proteins lipocalin-1 and tropomyosin and a hitherto not detected protein in plasma, zinc finger protein 483. The putative heparin-binding sequences were analyzed. The results suggest that the combination of group specific affinity and adapted immunodepletion chromatography could be useful in the study of the plasma proteome. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Heparin-Binding EGF-like Growth Factor (HB-EGF) Therapy for Intestinal Injury: Application and Future Prospects

    Science.gov (United States)

    Yang, Jixin; Su, Yanwei; Zhou, Yu; Besner, Gail E.

    2014-01-01

    Throughout the past 20 years, we have been investigating the potential therapeutic roles of heparin-binding EGF-like growth factor (HB-EGF), a member of the epidermal growth factor family, in various models of intestinal injury including necrotizing enterocolitis (NEC), intestinal ischemia/reperfusion (I/R) injury, and hemorrhagic shock and resuscitation (HS/R). Our studies have demonstrated that HB-EGF acts as an effective mitogen, a restitution-inducing reagent, a cellular trophic factor, an anti-apoptotic protein and a vasodilator, via its effects on various cell types in the intestine. In the current paper, we have reviewed the application and therapeutic effects of HB-EGF in three classic animal models of intestinal injury, with particular emphasis on its protection of the intestines from NEC. Additionally, we have summarized the protective functions of HB-EGF on various target cells in the intestine. Lastly, we have provided a brief discussion focusing on the future development of HB-EGF clinical applications for the treatment of various forms of intestinal injury including NEC. PMID:24345808

  2. Heparin-binding EGF-like growth factor (HB-EGF) promotes cell migration and adhesion via focal adhesion kinase.

    Science.gov (United States)

    Su, Yanwei; Besner, Gail E

    2014-06-15

    Cell migration and adhesion are essential in intestinal epithelial wound healing and recovery from injury. Focal adhesion kinase (FAK) plays an important role in cell-extracellular matrix signal transduction. We have previously shown that heparin-binding EGF-like growth factor (HB-EGF) promotes intestinal epithelial cell (IEC) migration and adhesion in vitro. The present study was designed to determine whether FAK is involved in HB-EGF-induced IEC migration and adhesion. A scrape wound healing model of rat IECs was used to examine the effect of HB-EGF on FAK-dependent cell migration in vitro. Immunofluorescence and Western blot analyses were performed to evaluate the effect of HB-EGF on the expression of phosphorylated FAK (p-FAK). Cell adhesion assays were performed to determine the role of FAK in HB-EGF-induced cell adhesion on fibronectin (FN). HB-EGF significantly increased healing after scrape wounding, an effect that was reversed in the presence of an FAK inhibitor 14 (both with P HB-EGF increased p-FAK expression and induced p-FAK redistribution and actin reorganization in migrating rat IECs. Cell adhesion and spreading on FN were significantly increased by HB-EGF (P HB-EGF-induced cell adhesion and spreading on FN (both with P HB-EGF-mediated IEC migration and adhesion. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Mice with genetic deletion of the heparin-binding growth factor midkine exhibit early preclinical features of Parkinson's disease.

    Science.gov (United States)

    Prediger, Rui D S; Rojas-Mayorquin, Argelia E; Aguiar, Aderbal S; Chevarin, Caroline; Mongeau, Raymond; Hamon, Michel; Lanfumey, Laurence; Del Bel, Elaine; Muramatsu, Hisako; Courty, José; Raisman-Vozari, Rita

    2011-08-01

    There is considerable evidence showing that the neurodegenerative processes that lead to sporadic Parkinson's disease (PD) begin many years before the appearance of the characteristic motor symptoms and that impairments in olfactory, cognitive and motor functions are associated with time-dependent disruption of dopaminergic neurotransmission in different brain areas. Midkine is a 13-kDa retinoic acid-induced heparin-binding growth factor involved in many biological processes in the central nervous system such as cell migration, neurogenesis and tissue repair. The abnormal midkine expression may be associated with neurochemical dysfunction in the dopaminergic system and cognitive impairments in rodents. Here, we employed adult midkine knockout mice (Mdk(-/-)) to further investigate the relevance of midkine in dopaminergic neurotransmission and in olfactory, cognitive and motor functions. Mdk(/-) mice displayed pronounced impairments in their olfactory discrimination ability and short-term social recognition memory with no gross motor alterations. Moreover, the genetic deletion of midkine decreased the expression of the enzyme tyrosine hydroxylase in the substantia nigra reducing partially the levels of dopamine and its metabolites in the olfactory bulb and striatum of mice. These findings indicate that the genetic deletion of midkine causes a partial loss of dopaminergic neurons and depletion of dopamine, resulting in olfactory and memory deficits with no major motor impairments. Therefore, Mdk(-/-) mice may represent a promising animal model for the study of the early stages of PD and for testing new therapeutic strategies to restore sensorial and cognitive processes in PD.

  4. Syndecan-4 binding to the high affinity heparin-binding domain of fibronectin drives focal adhesion formation in fibroblasts

    DEFF Research Database (Denmark)

    Woods, A; Longley, R L; Tumova, S

    2000-01-01

    Cell adhesion to extracellular matrix involves signaling mechanisms which control attachment, spreading and the formation of focal adhesions and stress fibers. Fibronectin can provide sufficient signals for all three processes, even when protein synthesis is prevented by cycloheximide. Primary fi...

  5. A synthetic peptide from the COOH-terminal heparin-binding domain of fibronectin promotes focal adhesion formation

    DEFF Research Database (Denmark)

    Woods, A; McCarthy, J B; Furcht, L T

    1993-01-01

    Cell adhesion to extracellular matrix molecules such as fibronectin involves complex transmembrane signaling processes. Attachment and spreading of primary fibroblasts can be promoted by interactions of cell surface integrins with RGD-containing fragments of fibronectin, but the further process......, as synthetic peptides coupled to ovalbumin, can support cell attachment. Only three of these sequences can promote focal adhesion formation when presented as multicopy complexes, and only one of these (WQPPRARI) retains this activity as free peptide. The major activity of this peptide resides in the sequence...... PRARI. The biological response to this peptide and to the COOH-terminal fragment may be mediated through cell surface heparan sulfate proteoglycans because treatment of cells with heparinase II and III, or competition with heparin, reduces the response. Treatment with chondroitinase ABC or competition...

  6. identification of heparin-binding sites in the fibronectin type III domains of the leukocyte common antigen (CD45)

    Czech Academy of Sciences Publication Activity Database

    Kavan, Daniel; Vančurová, M.; Ulbrichová, D.; Hladíková, I.; Pospíšil, Miloslav; Bezouška, Karel

    2004-01-01

    Roč. 3, č. 69 (2004), s. 645-658 ISSN 0010-0765 R&D Projects: GA AV ČR IAA7020006 Institutional research plan: CEZ:AV0Z5020903 Keywords : lectin-like receptors * lectins * antigens Subject RIV: EE - Microbiology, Virology Impact factor: 1.062, year: 2004

  7. Heparin-binding protein: an early indicator of critical illness and predictor of outcome in cardiac arrest.

    Science.gov (United States)

    Dankiewicz, Josef; Linder, Adam; Annborn, Martin; Rundgren, Malin; Friberg, Hans

    2013-07-01

    To investigate plasma levels of the neutrophil-borne heparin-binding protein (HBP) in patients with induced hypothermia after cardiac arrest (CA), and to study any association to severity of organ failure, incidence of infection and neurological outcome. This study included 84 patients with CA of mixed origin who were treated with hypothermia. Plasma samples from 7 time points during the first 72 h after return of spontaneous circulation (ROSC) were collected and analyzed for HBP with an ELISA. Outcomes were dichotomized: a cerebral performance category scale (CPC) of 1-2 at 6 months follow-up was considered a good outcome, a CPC of 3-5, a poor outcome. Patient data, including APACHE II and SOFA-scores were retrieved from the computerized system for quality assurance for intensive care. At 6 h and 12 h after CA, plasma levels of HBP were significantly higher among patients with a poor outcome. A receiver operated characteristics (ROC)-analysis yielded respective areas under curve (AUC) values of 0.68 and 0.70. This was similar to APACHE II and SOFA-score AUC values. There was a significant correlation between early elevated HBP-values and time to ROSC. HBP-levels were not higher in patients with infections at any time. Elevated HBP is an early indicator of organ failure and poor neurological outcome after CA, independent of microbial infection, and should be further evaluated in prospective trials. The temporal profile of HBP is suggestive of a role in the pathogenesis of critical illness after CA. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Increased Plasma Levels of Heparin-Binding Protein on Admission to Intensive Care Are Associated with Respiratory and Circulatory Failure.

    Directory of Open Access Journals (Sweden)

    Jonas Tydén

    Full Text Available Heparin-binding protein (HBP is released by granulocytes and has been shown to increase vascular permeability in experimental investigations. Increased vascular permeability in the lungs can lead to fluid accumulation in alveoli and respiratory failure. A generalized increase in vascular permeability leads to loss of circulating blood volume and circulatory failure. We hypothesized that plasma concentrations of HBP on admission to the intensive care unit (ICU would be associated with decreased oxygenation or circulatory failure.This is a prospective, observational study in a mixed 8-bed ICU. We investigated concentrations of HBP in plasma at admission to the ICU from 278 patients. Simplified acute physiology score (SAPS 3 was recorded on admission. Sequential organ failure assessment (SOFA scores were recorded daily for three days.Median SAPS 3 was 58.8 (48-70 and 30-day mortality 64/278 (23%. There was an association between high plasma concentrations of HBP on admission with decreased oxygenation (p<0.001 as well as with circulatory failure (p<0.001, after 48-72 hours in the ICU. There was an association between concentrations of HBP on admission and 30-day mortality (p = 0.002. ROC curves showed areas under the curve of 0,62 for decreased oxygenation, 0,65 for circulatory failure and 0,64 for mortality.A high concentration of HBP in plasma on admission to the ICU is associated with respiratory and circulatory failure later during the ICU care period. It is also associated with increased 30-day mortality. Despite being an interesting biomarker for the composite ICU population it's predictive value at the individual patient level is low.

  9. Neuregulins, Neuroprotection and Parkinson’s Disease

    Science.gov (United States)

    2006-09-01

    anti- rabbit IgG (1 : 400) for GFAP and NSE. Sections were taken through a series of rinses and then incubated in ABC-peroxidase reagent (Vector...electrophoresis, proteins were transferred to a polyvinylidene difluoride membrane (Bio- Rad). The membrane was blocked in 5% skim milk in Tris-buffered...heterodimerization. Neuregulins can directly bind to only the ErbB3 and ErbB4 receptors, which can then heterodimerize with ErbB2 (an orphan receptor

  10. Protein Phosphatase-1 Regulates Expression of Neuregulin-1

    Directory of Open Access Journals (Sweden)

    Tatiana Ammosova

    2016-12-01

    Full Text Available Protein phosphatase 1 (PP1, a cellular serine/threonine phosphatase, is targeted to cellular promoters by its major regulatory subunits, PP1 nuclear targeting subunit, nuclear inhibitor of PP1 (NIPP1 and RepoMan. PP1 is also targeted to RNA polymerase II (RNAPII by NIPP1 where it can dephosphorylate RNAPII and cycle-dependent kinase 9 (CDK9. Here, we show that treatment of cells with a small molecule activator of PP1 increases the abundance of a neuregulin-1 (NRG-1-derived peptide. NRG-1 mRNA and protein levels were increased in the cells stably or transiently expressing mutant NIPP1 (mNIPP1 that does not bind PP1, but not in the cells expressing NIPP1. Expression of mNIPP1 also activated the NRG-1 promoter in an NF-κB-dependent manner. Analysis of extracts from mNIPP1 expressing cells by glycerol gradient centrifugation showed a redistribution of PP1 and CDK9 between large and small molecular weight complexes, and increased CDK9 Thr-186 phosphorylation. This correlated with the increased CDK9 activity. Further, RNAPII co-precipitated with mNIPP1, and phosphorylation of RNAPII C-terminal domain (CTD Ser-2 residues was greater in cells expressing mNIPP1. In mNIPP1 expressing cells, okadaic acid, a cell-permeable inhibitor of PP1, did not increase Ser-2 CTD phosphorylation inhibited by flavopiridol, in contrast to the NIPP1 expressing cells, suggesting that PP1 was no longer involved in RNAPII dephosphorylation. Finally, media conditioned with mNIPP1 cells induced the proliferation of wild type 84-31 cells, consistent with a role of neuregulin-1 as a growth promoting factor. Our study indicates that deregulation of PP1/NIPP1 holoenzyme activates NRG-1 expression through RNAPII and CDK9 phosphorylation in a NF-κB dependent manner.

  11. Development of an ErbB4 monoclonal antibody that blocks neuregulin-1-induced ErbB4 activation in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Okazaki, Shogo [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nakatani, Fumi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Masuko, Kazue; Tsuchihashi, Kenji [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Ueda, Shiho; Masuko, Takashi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Saya, Hideyuki [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nagano, Osamu, E-mail: osmna@sb3.so-net.ne.jp [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan)

    2016-01-29

    The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix. - Highlights: • We newly generated four clones of human ErbB4 specific mAb. • ErbB4 mAb clone P6-1 blocks ErbB4 phosphorylation induced by NRG-1. • ErbB4 mAb clone P6-1 suppresses NRG-1-promoted breast cancer cells proliferation on three dimensional culture condition.

  12. BACE1-Dependent Neuregulin-1 Signaling: An Implication for Schizophrenia

    Directory of Open Access Journals (Sweden)

    Zhengrong Zhang

    2017-09-01

    Full Text Available Schizophrenia is a chronic psychiatric disorder with a lifetime prevalence of about 1% in the general population. Recent studies have shown that Neuregulin-1 (Nrg1 is a candidate gene for schizophrenia. At least 15 alternative splicing of NRG1 isoforms all contain an extracellular epidermal growth factor (EGF-like domain, which is sufficient for Nrg1 biological activity including the formation of myelin sheaths and the regulation of synaptic plasticity. It is known that Nrg1 can be cleaved by β-secretase (BACE1 and the resulting N-terminal fragment (Nrg1-ntf binds to receptor tyrosine kinase ErbB4, which activates Nrg1/ErbB4 signaling. While changes in Nrg1 expression levels in schizophrenia still remain controversial, understanding the BACE1-cleaved Nrg1-ntf and Nrg1/ErbB4 signaling in schizophrenia neuropathogenesis is essential and important. In this review paper, we included three major parts: (1 Nrg1 structure and cleavage pattern by BACE1; (2 BACE1-dependent Nrg1 cleavage associated with schizophrenia in human studies; and (3 Animal studies of Nrg1 and BACE1 mutations with behavioral observations. Our review will provide a better understanding of Nrg1 in schizophrenia and a potential strategy for using BACE1 cleavage of Nrg1 as a unique biomarker for diagnosis, as well as a new therapeutic target, of schizophrenia.

  13. Neuregulin 1 expression and electrophysiological abnormalities in the Neuregulin 1 transmembrane domain heterozygous mutant mouse

    National Research Council Canada - National Science Library

    Long, Leonora E; Anderson, Paul; Frank, Elisabeth; Shaw, Alex; Liu, Shijie; Huang, Xu-Feng; Pinault, Didier; Karl, Tim; O'Brien, Terence J; Shannon Weickert, Cynthia; Jones, Nigel C

    2015-01-01

    .... In addition, we investigate the regulation of high-frequency (gamma) electrophysiological oscillations in this mutant mouse to associate molecular changes in Nrg1 with a schizophrenia-relevant neurophysiological profile...

  14. Enhanced effect of BCG vaccine against pulmonary Mycobacterium tuberculosis infection in mice with lung Th17 response to mycobacterial heparin-binding hemagglutinin adhesin antigen.

    Science.gov (United States)

    Fukui, Masayuki; Shinjo, Kikuko; Umemura, Masayuki; Shigeno, Satoko; Harakuni, Tetsuya; Arakawa, Takeshi; Matsuzaki, Goro

    2015-12-01

    Although the BCG vaccine can prevent tuberculosis (TB) in infants, its ability to prevent adult pulmonary TB is reportedly limited. Therefore, development of a novel effective vaccine against pulmonary TB has become an international research priority. We have previously reported that intranasal vaccination of mice with a mycobacterial heparin-binding hemagglutinin adhesin (HBHA) plus mucosal adjuvant cholera toxin (CT) enhances production of IFN-γ and anti-HBHA antibody and suppresses extrapulmonary bacterial dissemination after intranasal infection with BCG. In the present study, the effects of intranasal HBHA + CT vaccine on murine pulmonary Mycobacterium tuberculosis (Mtb) infection were examined. Intranasal HBHA + CT vaccination alone failed to reduce the bacterial burden in the infected lung. However, a combination vaccine consisting of s.c. BCG priming and an intranasal HBHA + CT booster significantly enhanced protective immunity against pulmonary Mtb infection on day 14 compared with BCG vaccine alone. Further, it was found that intranasal HBHA + CT vaccine enhanced not only IFN-γ but also IL-17A production by HBHA-specific T cells in the lung after pulmonary Mtb infection. Therefore, this combination vaccine may be a good candidate for a new vaccine strategy against pulmonary TB. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

  15. Women with homozygous AT deficiency type II heparin-binding site (HBS) are at high risk of pregnancy loss and pregnancy complications.

    Science.gov (United States)

    Kraft, Julia; Sunder-Plassmann, Raute; Mannhalter, Christine; Quehenberger, Peter; Tews, Gernot; Langer, Martin; Pabinger, Ingrid

    2017-06-01

    Data regarding outcome and therapy of pregnancies in patients with homozygous antithrombin (AT) deficiency are very rare. We conducted a retrospective, descriptive investigation with emphasis on the obstetric history of eight women with homozygous AT deficiency heparin-binding site (HBS), who had at least one pregnancy. The aim of the study was to get a better insight into the outcome and identify suitable management procedures of pregnancy in this rare disease. All patients suffered from homozygous AT deficiency caused by the mutation c.391C>T p.Leu131Phe in the AT gene (SERPINC1). The women reported in total 23 pregnancies; one pregnancy was excluded because of induced abortion. We found that only seven out of the 22 analyzed pregnancies ended with a live infant, all of them were born preterm. Among the 15 negative outcomes, seven were early pregnancy losses and eight were intrauterine fetal deaths. We found no clear association between treatment protocols and outcome. Eight pregnancies were not treated at all; all of them ended with pregnancy loss. We conclude that homozygous AT deficiency HBS, a form of severe thrombophilia, is associated with high risk of pregnancy loss and preterm delivery. Rigorous anticoagulation and/or replacement of AT during pregnancy may improve the outcome.

  16. Serum Heparin-binding Epidermal Growth Factor-like Growth Factor (HB-EGF) as a Biomarker for Primary Ovarian Cancer.

    Science.gov (United States)

    Miyata, Kohei; Yotsumoto, Fusanori; Fukagawa, Satoshi; Kiyoshima, Chihiro; Ouk, Nam Sung; Urushiyama, Daichi; Ito, Tomohiro; Katsuda, Takahiro; Kurakazu, Masamitsu; Araki, Ryota; Sanui, Ayako; Miyahara, Daisuke; Murata, Masaharu; Shirota, Kyoko; Yagi, Hiroshi; Takono, Tadao; Kato, Kiyoko; Yaegashi, Nobuo; Akazawa, Kohei; Kuroki, Masahide; Yasunaga, Shin'ichiro; Miyamoto, Shingo

    2017-07-01

    Ovarian cancer is the most lethal malignancy among gynaecological cancers. Although many anticancer agents have been developed for the treatment of ovarian cancer, it continues to have an extremely poor prognosis. Heparin-binding epidermal growth factor-like grown factor (HB-EGF) has been reported to be a rational therapeutic target for ovarian cancer. Here, we evaluated the clinical significance of serum HB-EGF by examining the association between prognosis and serum HB-EGF levels in patients with primary ovarian cancer. We found that high serum HB-EGF concentrations were significantly associated with poor prognosis in a combined cohort of patients with all stages of ovarian cancer, as well as in a subset of patients with advanced disease. In addition, serum HB-EGF levels increased as the cancer advanced. These data suggest that serum HB-EGF may be a target for the design of novel therapies for ovarian cancer. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  17. Omeprazole and PGC-formulated heparin binding epidermal growth factor normalizes fasting blood glucose and suppresses insulitis in multiple low dose streptozotocin diabetes model

    Science.gov (United States)

    Castillo, Gerardo M.; Nishimoto-Ashfield, Akiko; Banerjee, Aryamitra A.; Landolfi, Jennifer A.; Lyubimov, Alexander V.; Bolotin, Elijah M.

    2013-01-01

    Purpose Our objective was to develop novel nanocarriers (protected graft copolymer, PGC) that improve the stability of heparin binding EGF (HBEGF) and gastrin and then to use PGC-formulated HBEGF (PGC-HBEGF) and Omeprazole (+/− PGC-gastrin) for normalizing fasting blood glucose (FBG) and improving islet function in diabetic mice. Method HBEGF, PGC-HBEGF, Omeprazole, Omeprazole+PGC-HBEGF, Omeprazole+PGC-gastrin+PGC-HBEGF and epidermal growth factor (EGF)+gastrin were tested in multiple low dose streptozotocin diabetic mice. Results Omeprazole+PGC-HBEGF normalized FBG and is better than EGF+gastrin at improving islet function and decreasing insulitis. Groups treated with Omeprazole, Omeprazole+PGC-HBEGF, or EGF+gastrin have significantly improved islet function versus saline control. All animals that received PGC-HBEGF had significantly reduced islet insulitis versus saline control. Non-FBG was lower for Omeprazole+PGC-gastrin+PGC-HBEGF but Omeprazole+PGC-HBEGF alone showed better FBG and glucose tolerance. Conclusions Omeprazole+PGC-HBEGF provides a sustained exposure to both EGFRA and gastrin, improves islet function, and decreases insulitis in multiple low dose streptozotocin diabetic mice. Although HBEGF or EGF elevates non-FBG, it facilitates a reduction of insulitis and, in the presence of Omeprazole, provides normalization of FBG at the end of treatment. The study demonstrates Omeprazole and PGC-HBEGF is a viable treatment for diabetes. PMID:23793991

  18. Diagnostic Utility of Neuregulin for Acute Coronary Syndrome

    Directory of Open Access Journals (Sweden)

    Maame Yaa A. B. Yiadom

    2016-01-01

    Full Text Available The purpose of this study was to determine the diagnostic test characteristics of serum neuregulin-1β (NRG-1β for the detection of acute coronary syndrome (ACS. We recruited emergency department patients presenting with signs and symptoms prompting an evaluation for ACS. Serum troponin and neuregulin-1β levels were compared between those who had a final discharge diagnosis of myocardial infarction (STEMI and NSTEMI and those who did not, as well as those who more broadly had a final discharge diagnosis of ACS (STEMI, NSTEMI, and unstable angina. Of 319 study participants, 11% had evidence of myocardial infarction, and 19.7% had a final diagnosis of ACS. Patients with MI had median neuregulin levels of 0.16 ng/mL (IQR [0.16–24.54]. Compared to the median of those without MI, 1.46 ng/mL (IQR [0.16–15.02], there was no significant difference in the distribution of results (P=0.63. Median neuregulin levels for patients with ACS were 0.65 ng/mL (IQR [0.16–24.54]. There was no statistical significance compared to those without ACS who had a median of 1.40 ng/mL (IQR [0.16–14.19] (P=0.95. Neuregulin did not perform successfully as a biomarker for acute MI or ACS in the emergency department.

  19. Diagnostic Utility of Neuregulin for Acute Coronary Syndrome

    Science.gov (United States)

    Greenberg, Jeremy; Smith, Holly M.; Sawyer, Douglas B.; Liu, Dandan; Carlise, Jahred; Tortora, Laura; Storrow, Alan B.

    2016-01-01

    The purpose of this study was to determine the diagnostic test characteristics of serum neuregulin-1β (NRG-1β) for the detection of acute coronary syndrome (ACS). We recruited emergency department patients presenting with signs and symptoms prompting an evaluation for ACS. Serum troponin and neuregulin-1β levels were compared between those who had a final discharge diagnosis of myocardial infarction (STEMI and NSTEMI) and those who did not, as well as those who more broadly had a final discharge diagnosis of ACS (STEMI, NSTEMI, and unstable angina). Of 319 study participants, 11% had evidence of myocardial infarction, and 19.7% had a final diagnosis of ACS. Patients with MI had median neuregulin levels of 0.16 ng/mL (IQR [0.16–24.54]). Compared to the median of those without MI, 1.46 ng/mL (IQR [0.16–15.02]), there was no significant difference in the distribution of results (P = 0.63). Median neuregulin levels for patients with ACS were 0.65 ng/mL (IQR [0.16–24.54]). There was no statistical significance compared to those without ACS who had a median of 1.40 ng/mL (IQR [0.16–14.19]) (P = 0.95). Neuregulin did not perform successfully as a biomarker for acute MI or ACS in the emergency department. PMID:27110055

  20. Heparin-binding EGF-like growth factor mediates oxyhemoglobin-induced suppression of voltage-dependent potassium channels in rabbit cerebral artery myocytes.

    Science.gov (United States)

    Koide, Masayo; Penar, Paul L; Tranmer, Bruce I; Wellman, George C

    2007-09-01

    Oxyhemoglobin (OxyHb) can suppress voltage-dependent K(+) channel (K(V)) currents through protein tyrosine kinase activation, which may contribute to cerebral vasospasm following subarachnoid hemorrhage. Here we have tested the hypothesis that shedding of heparin-binding EGF-like growth factor (HB-EGF) and the resulting activation of the tyrosine kinase EGF receptor (EGFR) underlie OxyHb-induced K(V) channel suppression in the cerebral vasculature. With the use of the conventional whole cell patch-clamp technique, two EGFR ligands, EGF and HB-EGF, were found to mimic OxyHb-induced K(V) suppression in rabbit cerebral artery myocytes. K(V) current suppression by OxyHb or EGF ligands was eliminated by a specific EGFR inhibitor, AG-1478, but was unaffected by PKC inhibition. Compounds (heparin and CRM-197) that specifically interfere with HB-EGF signaling eliminated OxyHb-induced K(V) suppression, suggesting that HB-EGF is the EGFR ligand involved in this pathway. HB-EGF exists as a precursor protein that, when cleaved by matrix metalloproteases (MMPs), causes EGFR activation. MMP activation was detected in OxyHb-treated arteries by gelatin zymography. Furthermore, the MMP inhibitor (GM-6001) abolished OxyHb-induced K(V) current suppression. We also observed K(V) current suppression due to EGFR activation in human cerebral artery myocytes. In conclusion, these data demonstrate that OxyHb induces MMP activation, causing HB-EGF shedding and enhanced EGFR activity, ultimately leading to K(V) channel suppression. We propose that EGFR-mediated K(V) suppression contributes to vascular pathologies, such as cerebral vasospasm, and may play a more widespread role in the regulation of regional blood flow and peripheral resistance.

  1. Expression of Heparin-Binding EGF-Like Growth Factor (HB-EGF) in Bovine Endometrium: Effects of HB-EGF and Interferon-τ on Prostaglandin Production.

    Science.gov (United States)

    Takatsu, K; Acosta, T J

    2015-06-01

    Heparin-binding EGF-like growth factor (HB-EGF) regulates several cell functions by binding to its membrane receptor (ErbB1 and ErbB4). Experimental evidences suggest that HB-EGF, prostaglandins (PGs) and interferon-τ (IFN-τ) regulate uterine function for pregnancy establishment in ruminants. In this study, the mRNA expressions of HB-EGF, ErbB1 and ErbB4 in bovine endometrium and the effects of HB-EGF and IFN-τ on PGE2 and PGF2-α production by endometrial cells were investigated. RT-PCR analysis revealed that HB-EGF mRNA was greater at the mid-luteal stage than at the early and regressed luteal stages (p HB-EGF, ErbB1 and ErbB4 mRNA in epithelial cells (p HB-EGF did not affect PGF2-α or PGE2 production by bovine endometrial epithelial cells, but increased PGF2-α and PGE2 production by bovine endometrial stromal cells (p HB-EGF-stimulated PGF2-α (p  0.05) production by stromal cells. These results indicate that HB-EGF and its receptors expression changed in bovine endometrium throughout the oestrous cycle. IFN-τ increased their expression in cultured endometrial cells. HB-EGF and IFN-τ have the ability to regulate PGs production by stromal cells and therefore may play a role in the local regulation of uterine function at the time of implantation in cattle. © 2015 Blackwell Verlag GmbH.

  2. Targeting hepatic heparin-binding EGF-like growth factor (HB-EGF) induces anti-hyperlipidemia leading to reduction of angiotensin II-induced aneurysm development.

    Science.gov (United States)

    Kim, Seonwook; Yang, Lihua; Kim, Seongu; Lee, Richard G; Graham, Mark J; Berliner, Judith A; Lusis, Aldons J; Cai, Lei; Temel, Ryan E; Rateri, Debra L; Lee, Sangderk

    2017-01-01

    The upregulated expression of heparin binding EGF-like growth factor (HB-EGF) in the vessel and circulation is associated with risk of cardiovascular disease. In this study, we tested the effects of HB-EGF targeting using HB-EGF-specific antisense oligonucleotide (ASO) on the development of aortic aneurysm in a mouse aneurysm model. Low-density lipoprotein receptor (LDLR) deficient mice (male, 16 weeks of age) were injected with control and HB-EGF ASOs for 10 weeks. To induce aneurysm, the mice were fed a high fat diet (22% fat, 0.2% cholesterol; w/w) at 5 week point of ASO administration and infused with angiotensin II (AngII, 1,000ng/kg/min) for the last 4 weeks of ASO administration. We confirmed that the HB-EGF ASO administration significantly downregulated HB-EGF expression in multiple tissues including the liver. Importantly, the HB-EGF ASO administration significantly suppressed development of aortic aneurysms including thoracic and abdominal types. Interestingly, the HB-EGF ASO administration induced a remarkable anti-hyperlipidemic effect by suppressing very low density lipoprotein (VLDL) level in the blood. Mechanistically, the HB-EGF targeting suppressed hepatic VLDL secretion rate without changing heparin-releasable plasma triglyceride (TG) hydrolytic activity or fecal neutral cholesterol excretion rate. This result suggested that the HB-EGF targeting induced protection against aneurysm development through anti-hyperlipidemic effects. Suppression of hepatic VLDL production process appears to be a key mechanism for the anti-hyperlipidemic effects by the HB-EGF targeting.

  3. Heparin-binding EGF-like growth factor (HB-EGF) stimulates the proliferation of Müller glia-derived progenitor cells in avian and murine retinas.

    Science.gov (United States)

    Todd, Levi; Volkov, Leo I; Zelinka, Chris; Squires, Natalie; Fischer, Andy J

    2015-11-01

    Müller glia can be stimulated to de-differentiate, proliferate and form Müller glia-derived progenitor cells (MGPCs) that regenerate retinal neurons. In the zebrafish retina, heparin-binding EGF-like growth factor (HB-EGF) may be one of the key factors that stimulate the formation of proliferating MGPCs. Currently nothing is known about the influence of HB-EGF on the proliferative potential of Müller glia in retinas of birds and rodents. In the chick retina, we found that levels of both hb-egf and egf-receptor are rapidly and transiently up-regulated following NMDA-induced damage. Although intraocular injections of HB-EGF failed to stimulate cell-signaling or proliferation of Müller glia in normal retinas, HB-EGF stimulated proliferation of MGPCs in damaged retinas. By comparison, inhibition of the EGF-receptor (EGFR) decreased the proliferation of MGPCs in damaged retinas. HB-EGF failed to act synergistically with FGF2 to stimulate the formation of MGPCs in the undamaged retina and inhibition of EGF-receptor did not suppress FGF2-mediated formation of MGPCs. In the mouse retina, HB-EGF stimulated the proliferation of Müller glia following NMDA-induced damage. Furthermore, HB-EGF not only stimulated MAPK-signaling in Müller glia/MGPCs, but also activated mTor- and Jak/Stat-signaling. We propose that levels of expression of EGFR are rate-limiting to the responses of Müller glia to HB-EGF and the expression of EGFR can be induced by retinal damage, but not by FGF2-treatment. We conclude that HB-EGF is mitogenic to Müller glia in both chick and mouse retinas, and HB-EGF is an important player in the formation of MGPCs in damaged retinas. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Conditional loss of heparin-binding EGF-like growth factor results in enhanced liver fibrosis after bile duct ligation in mice

    Energy Technology Data Exchange (ETDEWEB)

    Takemura, Takayo; Yoshida, Yuichi [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan); Kiso, Shinichi, E-mail: kiso@gh.med.osaka-u.ac.jp [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan); Kizu, Takashi; Furuta, Kunimaro; Ezaki, Hisao; Hamano, Mina; Egawa, Mayumi; Chatani, Norihiro; Kamada, Yoshihiro [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan); Imai, Yasuharu [Department of Gastroenterology, Ikeda Municipal Hospital, Ikeda, Osaka (Japan); Higashiyama, Shigeki [Department of Biochemistry and Molecular Genetics, Ehime University, Graduate School of Medicine and Department of Cell Growth and Tumor Regulation, Proteo-Medicine Research Center (ProMRes), Ehime University, Shitsukawa, Toon, Ehime (Japan); Iwamoto, Ryo; Mekada, Eisuke [Department of Cell Biology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Takehara, Tetsuo [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan)

    2013-07-26

    Highlights: •HB-EGF expression was increased during the development of liver fibrosis. •Conditional HB-EGF knockout mouse showed enhanced experimental liver fibrosis. •HB-EGF antagonized TGF-β-induced activation of hepatic stellate cells. •We report a possible protective role of HB-EGF in cholestatic liver fibrosis. -- Abstract: Our aims were to evaluate the involvement of heparin-binding EGF-like growth factor (HB-EGF) in liver fibrogenesis of humans and mice and to elucidate the effect of HB-EGF deficiency on cholestatic liver fibrosis using conditional HB-EGF knockout (KO) mice. We first demonstrated that gene expression of HB-EGF had a positive significant correlation with that of collagen in human fibrotic livers, and was increased in bile duct ligation (BDL)-induced fibrotic livers in mouse. We then generated conditional HB-EGF knockout (KO) mice using the interferon inducible Mx-1 promoter driven Cre recombinase transgene and wild type (WT) and KO mice were subjected to BDL. After BDL, KO mice exhibited enhanced liver fibrosis with increased expression of collagen, compared with WT mice. Finally, we used mouse hepatic stellate cells (HSCs) to examine the role of HB-EGF in the activation of these cells and showed that HB-EGF antagonized TGF-β-induced gene expression of collagen in mouse primary HSCs. Interestingly, HB-EGF did not prevent the TGF-β-induced nuclear accumulation of Smad3, but did lead to stabilization of the Smad transcriptional co-repressor TG-interacting factor. In conclusion, our data suggest a possible protective role of HB-EGF in cholestatic liver fibrosis.

  5. Heparin-binding epidermal growth factor expression in KATO-III cells after Helicobacter pylori stimulation under the influence of strychnos Nux vomica and Calendula officinalis.

    Science.gov (United States)

    Hofbauer, Roland; Pasching, Eva; Moser, Doris; Frass, Michael

    2010-07-01

    Previous studies have shown the stimulating effect of Helicobacter pylori on the gene expression of heparin-binding epidermal growth factor (HB-EGF) using the gastric epithelial cell line KATO-III. Strychnos Nux vomica (Nux vomica) and Calendula officinalis are used in highly diluted form in homeopathic medicine to treat patients suffering from gastritis and gastric ulcers. To investigate the influence of Nux vomica and Calendula officinalis on HB-EGF-like growth factor gene expression in KATO-III cells under the stimulation of H. pylori strain N6 using real-time PCR with and without addition of Nux vomica and Calendula officinalis as a 10c or 12c potency. Baseline expression and stimulation were similar to previous experiments, addition of Nux vomica 10c and Calendula officinalis 10c in a 43% ethanolic solution led to a significant reduction of H. pylori induced increase in gene expression of HB-EGF (reduced to 53.12+/-0.95% and 75.32+/-1.16% vs. control; p<0.05), respectively. Nux vomica 12c reduced HB-EGF gene expression even in dilutions beyond Avogadro's number (55.77+/-1.09%; p<0.05). Nux vomica 12c in a 21.5% ethanol showed a smaller effect (71.80+/-3.91%, p<0.05). This effect was only be observed when the drugs were primarily prepared in ethanol, not in aqueous solutions. The data suggest that both drugs prepared in ethanolic solution are potent inhibitors of H. pylori induced gene expression. 2010 Elsevier Ltd. All rights reserved.

  6. Neuregulin-1 genotypes and eye movements in schizophrenia

    DEFF Research Database (Denmark)

    Haraldsson, H.M.; Ettinger, U.; Magnusdottir, B.B.

    2010-01-01

    Neuregulin-1 (NRG-1) is a putative susceptibility gene for schizophrenia but the neurocognitive processes that may involve NRG-1 in schizophrenia are unknown. Deficits in antisaccade (AS) and smooth pursuit eye movements (SPEM) are promising endophenotypes, which may be associated with brain...... findings of impaired AS and SPEM performance in schizophrenia patients (all P eye movement variables...

  7. BB0347, from the lyme disease spirochete Borrelia burgdorferi, is surface exposed and interacts with the CS1 heparin-binding domain of human fibronectin.

    Directory of Open Access Journals (Sweden)

    Robert A Gaultney

    Full Text Available The causative agent of Lyme disease, Borrelia burgdorferi, codes for several known fibronectin-binding proteins. Fibronectin a common the target of diverse bacterial pathogens, and has been shown to be essential in allowing for the development of certain disease states. Another borrelial protein, BB0347, has sequence similarity with these other known fibronectin-binding proteins, and may be important in Lyme disease pathogenesis. Herein, we perform an initial characterization of BB0347 via the use of molecular and biochemical techniques. We found that BB0347 is expressed, produced, and presented on the outer surface of intact B. burgdorferi. We also demonstrate that BB0347 has the potential to be important in Lyme disease progression, and have begun to characterize the nature of the interaction between human fibronectin and this bacterial protein. Further work is needed to define the role of this protein in the borrelial infection process.

  8. Ectodomain cleavage of the EGF ligands HB-EGF, neuregulin1-beta, and TGF-alpha is specifically triggered by different stimuli and involves different PKC isoenzymes.

    Science.gov (United States)

    Herrlich, Andreas; Klinman, Eva; Fu, Jonathan; Sadegh, Cameron; Lodish, Harvey

    2008-12-01

    Metalloproteinase cleavage of transmembrane proteins (ectodomain cleavage), including the epidermal growth factor (EGF) ligands heparin-binding EGF-like growth factor (HB-EGF), neuregulin (NRG), and transforming growth factor-alpha (TGF-alpha), is important in many cellular signaling pathways and is disregulated in many diseases. It is largely unknown how physiological stimuli of ectodomain cleavage--hypertonic stress, phorbol ester, or activation of G-protein-coupled receptors [e.g., by lysophosphatidic acid (LPA)]--are molecularly connected to metalloproteinase activation. To study this question, we developed a fluorescence-activated cell sorting (FACS)- based assay that measures cleavage of EGF ligands in single living cells. EGF ligands expressed in mouse lung epithelial cells are differentially and specifically cleaved depending on the stimulus. Inhibition of protein kinase C (PKC) isoenzymes or metalloproteinase inhibition by batimastat (BB94) showed that different regulatory signals are used by different stimuli and EGF substrates, suggesting differential effects that act on the substrate, the metalloproteinase, or both. For example, hypertonic stress led to strong cleavage of HB-EGF and NRG but only moderate cleavage of TGF-alpha. HB-EGF, NRG, and TGF-alpha cleavage was not dependent on PKC, and only HB-EGF and NRG cleavage were inhibited by BB94. In contrast, phorbol 12-myristate-13-acetate (TPA) -induced cleavage of HB-EGF, NRG, and TGF-alpha was dependent on PKC and sensitive to BB94 inhibition. LPA led to significant cleavage of only NRG and TGF-alpha and was inhibited by BB94; only LPA-induced NRG cleavage required PKC. Surprisingly, specific inhibition of atypical PKCs zeta and iota [not activated by diacylglycerol (DAG) and calcium] significantly enhanced TPA-induced NRG cleavage. Employed in a high-throughput cloning strategy, our cleavage assay should allow the identification of candidate proteins involved in signal transduction of different

  9. Participation of heparin binding proteins from the surface of Leishmania (Viannia) braziliensis promastigotes in the adhesion of parasites to Lutzomyia longipalpis cells (Lulo) in vitro

    Science.gov (United States)

    2012-01-01

    Background Leishmania (V.) braziliensis is a causative agent of cutaneous leishmaniasis in Brazil. During the parasite life cycle, the promastigotes adhere to the gut of sandflies, to avoid being eliminated with the dejection. The Lulo cell line, derived from Lutzomyia longipalpis (Diptera: Psychodidae), is a suitable in vitro study model to understand the features of parasite adhesion. Here, we analyze the role of glycosaminoglycans (GAGs) from Lulo cells and proteins from the parasites in this event. Methods Flagellar (Ff) and membrane (Mf) fractions from promastigotes were obtained by differential centrifugation and the purity of fractions confirmed by western blot assays, using specific antibodies for cellular compartments. Heparin-binding proteins (HBP) were isolated from both fractions using a HiTrap-Heparin column. In addition, binding of promastigotes to Lulo cells or to a heparin-coated surface was assessed by inhibition assays or surface plasmon resonance (SPR) analysis. Results The success of promastigotes subcellular fractionation led to the obtainment of Ff and Mf proteins, both of which presented two main protein bands (65.0 and 55.0kDa) with affinity to heparin. The contribution of HBPs in the adherence of promastigotes to Lulo cells was assessed through competition assays, using HS or the purified HBPs fractions. All tested samples presented a measurable inhibition rate when compared to control adhesion rate (17 ± 2.0% of culture cells with adhered parasites): 30% (for HS 20μg/ml) and 16% (for HS 10μg/ml); HBP Mf (35.2% for 10μg/ml and 25.4% for 20μg/ml) and HBP Ff (10.0% for 10μg/ml and 31.4% for 20μg/ml). Additionally, to verify the presence of sulfated GAGs in Lulo cells surface and intracellular compartment, metabolic labeling with radioactive sulfate was performed, indicating the presence of an HS and chondroitin sulfate in both cell sections. The SPR analysis performed further confirmed the presence of GAGs ligands on L. (V

  10. Neuregulin-1 genotypes and eye movements in schizophrenia

    DEFF Research Database (Denmark)

    Haraldsson, H.M.; Ettinger, U.; Magnusdottir, B.B.

    2010-01-01

    Neuregulin-1 (NRG-1) is a putative susceptibility gene for schizophrenia but the neurocognitive processes that may involve NRG-1 in schizophrenia are unknown. Deficits in antisaccade (AS) and smooth pursuit eye movements (SPEM) are promising endophenotypes, which may be associated with brain...... dysfunctions underlying the pathophysiology of schizophrenia. The aim of this study was to investigate the associations of NRG-1 genotypes with AS and SPEM in schizophrenia patients and healthy controls. Patients (N = 113) and controls (N = 106) were genotyped for two NRG-1 single nucleotide polymorphisms...... findings of impaired AS and SPEM performance in schizophrenia patients (all P

  11. Neuregulin Driven Cell Differentiation, Transformation, and Parity of Luminal Breast Cancer

    Science.gov (United States)

    2013-12-01

    alveolar mammary epithelium for specific analysis of neuregulin loss in mammary morphogenesis, lactational differentiation, and breast cancer development...15. SUBJECT TERMS Breast Cancer, ErbB3, ErbB4, Neuregulin. Lactation , Pregnancy 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...pregnancy, producing milk during lactation . Loss of ErbB4 prevents growth of the alveolar epithelium due to loss of STAT5A signaling. ErbB4 interacts

  12. Expression pattern of neuregulin-1 type III during the development of the peripheral nervous system

    Directory of Open Access Journals (Sweden)

    Liang-liang Huang

    2015-01-01

    Full Text Available Neuregulin-1 type III is a key regulator in Schwann cell proliferation, committing to a myelinating fate and regulating myelin sheath thickness. However, the expression pattern of neuregulin-1 type III in the peripheral nervous system during developmental periods (such as the premyelinating stage, myelinating stage and postmyelinating stage has rarely been studied. In this study, dorsal root ganglia were isolated from rats between postnatal day 1 and postnatal day 56. The expression pattern of neuregulin-1 type III in dorsal root ganglia neurons at various developmental stages were compared by quantitative real-time polymerase chain reaction, western blot assay and immunofluorescent staining. The expression of neuregulin-1 type III mRNA reached its peak at postnatal day 3 and then stabilized at a relative high expression level from postnatal day 3 to postnatal day 56. The expression of neuregulin-1 type III protein increased gradually from postnatal day 1, reached a peak at postnatal day 28, and then decreased at postnatal day 56. Immunofluorescent staining results showed a similar tendency to western blot assay results. Experimental findings indicate that the expression of neuregulin-1 type III in rat dorsal root ganglion was increased during the premyelinating (from postnatal day 2 to postnatal day 5 and myelinating stage (from postnatal day 5 to postnatal day 10, but remained at a high level in the postmyelinating stage (after postnatal day 10.

  13. Behavioural effects of high fat diet in a mutant mouse model for the schizophrenia risk gene neuregulin 1

    DEFF Research Database (Denmark)

    Holm-hansen, S.; Low, J. K.; Zieba, J.

    2016-01-01

    on the behavioural phenotype of test mice and attenuated particular cognitive deficits of Nrg1 mutant females. This topic requires further investigations thereby also considering other dietary factors of relevance for schizophrenia as well as interactive effects of diet with medication and sex.......Schizophrenia patients are often obese or overweight and poor dietary choices appear to be a factor in this phenomenon. Poor diet has been found to have complex consequences for the mental state of patients. Thus, this study investigated whether an unhealthy diet [i.e. high fat diet (HFD)] impacts...... on the behaviour of a genetic mouse model for the schizophrenia risk gene neuregulin 1 (i.e. transmembrane domain Nrg1 mutant mice: Nrg1 HET). Female Nrg1 HET and wild-type-like littermates (WT) were fed with either HFD or a control chow diet. The mice were tested for baseline (e.g. anxiety) and schizophrenia...

  14. Neuregulin-1 mutant mice indicate motor and sensory deficits, indeed few references for schizophrenia endophenotype model.

    Science.gov (United States)

    Schneider, Silvia; Götz, Katja; Birchmeier, Carmen; Schwegler, Herbert; Roskoden, Thomas

    2017-03-30

    Neuregulins (Nrg) are a gene family that binds to tyrosine kinase receptors of the ErbB family. The protein of Nrg1 is to be involved in heart formation, migration of neurons, axonal pathfinding and synaptic function. A relation between Nrg1 and schizophrenia is assumed. Chronic impairment in schizophrenia is characterized by different positive and negative symptoms. Detectable markers of this disease in human and in animal models are activity, social behavior and sensory processing. In this study we compared heterozygous Nrg1 mutant mice in behavior and quantification of dopaminergic and serotoninergic neurons with wild type-like littermates. In the Nrg1 mutant mice the epidermal growth factor-like domain is replaced by the neomycin resistance gene. We found significant differences in locomotor and pain perception behavior. No differences were found in specific schizophrenia social interaction and prepulse inhibition behavior. The number of dopaminergic and serotoninergic neurons did not differ in the investigated regions ventral tegmental area, substantia nigra, periaqueductal grey and raphe nuclei. In conclusion, this analyzed Nrg1 mutant mice model did not serve as a complete schizophrenia model. Particular aspects of schizophrenia disease in locomotor and sensory behavior deficits could represent in this Nrg1 mutant mice. Beside several different models could Nrg1 deficiency represent an endophenotype of schizophrenia disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Dysregulated Expression of Neuregulin-1 by Cortical Pyramidal Neurons Disrupts Synaptic Plasticity

    Directory of Open Access Journals (Sweden)

    Amit Agarwal

    2014-08-01

    Full Text Available Neuregulin-1 (NRG1 gene variants are associated with increased genetic risk for schizophrenia. It is unclear whether risk haplotypes cause elevated or decreased expression of NRG1 in the brains of schizophrenia patients, given that both findings have been reported from autopsy studies. To study NRG1 functions in vivo, we generated mouse mutants with reduced and elevated NRG1 levels and analyzed the impact on cortical functions. Loss of NRG1 from cortical projection neurons resulted in increased inhibitory neurotransmission, reduced synaptic plasticity, and hypoactivity. Neuronal overexpression of cysteine-rich domain (CRD-NRG1, the major brain isoform, caused unbalanced excitatory-inhibitory neurotransmission, reduced synaptic plasticity, abnormal spine growth, altered steady-state levels of synaptic plasticity-related proteins, and impaired sensorimotor gating. We conclude that an “optimal” level of NRG1 signaling balances excitatory and inhibitory neurotransmission in the cortex. Our data provide a potential pathomechanism for impaired synaptic plasticity and suggest that human NRG1 risk haplotypes exert a gain-of-function effect.

  16. ERBB4 Mutations that Disrupt the Neuregulin-ErbB4 Pathway Cause Amyotrophic Lateral Sclerosis Type 19

    Science.gov (United States)

    Takahashi, Yuji; Fukuda, Yoko; Yoshimura, Jun; Toyoda, Atsushi; Kurppa, Kari; Moritoyo, Hiroyoko; Belzil, Veronique V.; Dion, Patrick A.; Higasa, Koichiro; Doi, Koichiro; Ishiura, Hiroyuki; Mitsui, Jun; Date, Hidetoshi; Ahsan, Budrul; Matsukawa, Takashi; Ichikawa, Yaeko; Moritoyo, Takashi; Ikoma, Mayumi; Hashimoto, Tsukasa; Kimura, Fumiharu; Murayama, Shigeo; Onodera, Osamu; Nishizawa, Masatoyo; Yoshida, Mari; Atsuta, Naoki; Sobue, Gen; Fifita, Jennifer A.; Williams, Kelly L.; Blair, Ian P.; Nicholson, Garth A.; Gonzalez-Perez, Paloma; Brown, Robert H.; Nomoto, Masahiro; Elenius, Klaus; Rouleau, Guy A.; Fujiyama, Asao; Morishita, Shinichi; Goto, Jun; Tsuji, Shoji

    2013-01-01

    Amyotrophic lateral sclerosis (ALS) is a devastating neurological disorder characterized by the degeneration of motor neurons and typically results in death within 3–5 years from onset. Familial ALS (FALS) comprises 5%–10% of ALS cases, and the identification of genes associated with FALS is indispensable to elucidating the molecular pathogenesis. We identified a Japanese family affected by late-onset, autosomal-dominant ALS in which mutations in genes known to be associated with FALS were excluded. A whole- genome sequencing and parametric linkage analysis under the assumption of an autosomal-dominant mode of inheritance with incomplete penetrance revealed the mutation c.2780G>A (p. Arg927Gln) in ERBB4. An extensive mutational analysis revealed the same mutation in a Canadian individual with familial ALS and a de novo mutation, c.3823C>T (p. Arg1275Trp), in a Japanese simplex case. These amino acid substitutions involve amino acids highly conserved among species, are predicted as probably damaging, and are located within a tyrosine kinase domain (p. Arg927Gln) or a C-terminal domain (p. Arg1275Trp), both of which mediate essential functions of ErbB4 as a receptor tyrosine kinase. Functional analysis revealed that these mutations led to a reduced autophosphorylation of ErbB4 upon neuregulin-1 (NRG-1) stimulation. Clinical presentations of the individuals with mutations were characterized by the involvement of both upper and lower motor neurons, a lack of obvious cognitive dysfunction, and relatively slow progression. This study indicates that disruption of the neuregulin-ErbB4 pathway is involved in the pathogenesis of ALS and potentially paves the way for the development of innovative therapeutic strategies such using NRGs or their agonists to upregulate ErbB4 functions. PMID:24119685

  17. Involvement of three meningococcal surface-exposed proteins, the heparin-binding protein NhbA, the α-peptide of IgA protease and the autotransporter protease NalP, in initiation of biofilm formation

    KAUST Repository

    Arenas, Jesús

    2012-12-04

    Neisseria meningitidis is a common and usually harmless inhabitant of the mucosa of the human nasopharynx, which, in rare cases, can cross the epithelial barrier and cause meningitis and sepsis. Biofilm formation favours the colonization of the host and the subsequent carrier state. Two different strategies of biofilm formation, either dependent or independent on extracellular DNA (eDNA), have been described for meningococcal strains. Here, we demonstrate that the autotransporter protease NalP, the expression of which is phase variable, affects eDNA-dependent biofilm formation in N.meningitidis. The effect of NalP was found in biofilm formation under static and flow conditions and was dependent on its protease activity. Cleavage of the heparin-binding antigen NhbA and the α-peptide of IgA protease, resulting in the release of positively charged polypeptides from the cell surface, was responsible for the reduction in biofilm formation when NalP is expressed. Both NhbA and the α-peptide of IgA protease were shown to bind DNA. We conclude that NhbA and the α-peptide of IgA protease are implicated in biofilm formation by binding eDNA and that NalP is an important regulator of this process through the proteolysis of these surface-exposed proteins. © 2012 Blackwell Publishing Ltd.

  18. Characterization of glial cell models and in vitro manipulation of the neuregulin1/ErbB system

    NARCIS (Netherlands)

    Pascal, Davide; Giovannelli, Alessia; Gnavi, Sara; Hoyng, Stefan Adriaan; de Winter, Fred; Morano, Michela; Fregnan, Federica; Dell'Albani, Paola; Zaccheo, Damiano; Perroteau, Isabelle; Pellitteri, Rosalia; Gambarotta, Giovanna

    2014-01-01

    The neuregulin1/ErbB system plays an important role in Schwann cell behavior both in normal and pathological conditions. Upon investigation of the expression of the neuregulin1/ErbB system in vitro, we explored the possibility to manipulate the system in order to increase the migration of Schwann

  19. An RBCC protein implicated in maintenance of steady-state neuregulin receptor levels.

    Science.gov (United States)

    Diamonti, A John; Guy, Pamela M; Ivanof, Caryn; Wong, Karen; Sweeney, Colleen; Carraway, Kermit L

    2002-03-05

    Despite numerous recent advances in our understanding of the molecular mechanisms underlying receptor tyrosine kinase down-regulation and degradation in response to growth factor binding, relatively little is known about ligand-independent receptor tyrosine kinase degradation mechanisms. In a screen for proteins that might regulate the trafficking or localization of the ErbB3 receptor, we have identified a tripartite or RBCC (RING, B-box, coiled-coil) protein that interacts with the cytoplasmic tail of the receptor in an activation-independent manner. We have named this protein Nrdp1 for neuregulin receptor degradation protein-1. Northern blotting reveals ubiquitous distribution of Nrdp1 in human adult tissues, but message is particularly prominent in heart, brain, and skeletal muscle. Nrdp1 interacts specifically with the neuregulin receptors ErbB3 and ErbB4 and not with epidermal growth factor receptor or ErbB2. When coexpressed in COS7 cells, Nrdp1 mediates the redistribution of ErbB3 from the cell surface to intracellular compartments and induces the suppression of ErbB3 and ErbB4 receptor levels but not epidermal growth factor receptor or ErbB2 levels. A putative dominant-negative form of Nrdp1 potentiates neuregulin-stimulated Erk1/2 activity in transfected MCF7 breast tumor cells. Our observations suggest that Nrdp1 may act to regulate steady-state cell surface neuregulin receptor levels, thereby influencing the efficiency of neuregulin signaling.

  20. Measurement of phenotype and absolute number of circulating heparin-binding hemagglutinin, ESAT-6 and CFP-10, and purified protein derivative antigen-specific CD4 T cells can discriminate active from latent tuberculosis infection.

    Science.gov (United States)

    Hutchinson, Paul; Barkham, Timothy M S; Tang, Wenying; Kemeny, David M; Chee, Cynthia Bin-Eng; Wang, Yee T

    2015-02-01

    The tuberculin skin test (TST) and interferon gamma (IFN-γ) release assays (IGRAs) are used as adjunctive tests for the evaluation of suspected cases of active tuberculosis (TB). However, a positive test does not differentiate latent from active TB. We investigated whether flow cytometric measurement of novel combinations of intracellular cytokines and surface makers on CD4 T cells could differentiate between active and latent TB after stimulation with Mycobacterium tuberculosis-specific proteins. Blood samples from 60 patients referred to the Singapore Tuberculosis Control Unit for evaluation for active TB or as TB contacts were stimulated with purified protein derivative (PPD), ESAT-6 and CFP-10, or heparin-binding hemagglutinin (HBHA). The CD4 T cell cytokine response (IFN-γ, interleukin-2 [IL-2], interleukin-17A [IL-17A], interleukin-22 [IL-22], granulocyte-macrophage colony-stimulating factor [GM-CSF], and tumor necrosis factor alpha [TNF-α]) and surface marker expression (CD27, CXCR3, and CD154) were then measured. We found that the proportion of PPD-specific CD4 T cells, defined as CD154(+) TNF-α(+) cells that were negative for CD27 and positive for GM-CSF, gave the strongest discrimination between subjects with latent and those with active TB (area under the receiver operator characteristic [ROC] curve of 0.9277; P CFP-10-responding to HBHA-responding CD4 T cells was significantly different between the two study populations. In conclusion, we found novel markers of M. tuberculosis-specific CD4 cells which differentiate between active and latent TB. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. Neuregulin 1 Prevents Phencyclidine-Induced Behavioral Impairments and Disruptions to GABAergic Signaling in Mice.

    Science.gov (United States)

    Engel, Martin; Snikeris, Peta; Jenner, Andrew; Karl, Tim; Huang, Xu-Feng; Frank, Elisabeth

    2015-05-01

    Substantial evidence from human post-mortem and genetic studies has linked the neurotrophic factor neuregulin 1 (NRG1) to the pathophysiology of schizophrenia. Genetic animal models and in vitro experiments have suggested that altered NRG1 signaling, rather than protein changes, contributes to the symptomatology of schizophrenia. However, little is known about the effect of NRG1 on schizophrenia-relevant behavior and neurotransmission (particularly GABAergic and glutamatergic) in adult animals. To address this question, we treated adult mice with the extracellular signaling domain of NRG1 and assessed spontaneous locomotor activity and acoustic startle response, as well as extracellular GABA, glutamate, and glycine levels in the prefrontal cortex and hippocampus via microdialysis. Furthermore, we asked whether the effect of NRG1 would differ under schizophrenia-relevant impairments in mice and therefore co-treated mice with NRG1 and phencyclidine (PCP) (3 mg/kg). Acute intraventricularly- or systemically-injected NRG1 did not affect spontaneous behavior, but prevented PCP induced hyperlocomotion and deficits of prepulse inhibition. NRG1 retrodialysis (10 nM) reduced extracellular glutamate and glycine levels in the prefrontal cortex and hippocampus, and prevented PCP-induced increase in extracellular GABA levels in the hippocampus. With these results, we provide the first compelling in vivo evidence for the involvement of NRG1 signaling in schizophrenia-relevant behavior and neurotransmission in the adult nervous system, which highlight its treatment potential. Furthermore, the ability of NRG1 treatment to alter GABA, glutamate, and glycine levels in the presence of PCP also suggests that NRG1 signaling has the potential to alter disrupted neurotransmission in patients with schizophrenia.

  2. Neuronal merlin influences ERBB2 receptor expression on Schwann cells through neuregulin 1 type III signalling.

    Science.gov (United States)

    Schulz, Alexander; Kyselyova, Anna; Baader, Stephan L; Jung, Marie Juliane; Zoch, Ansgar; Mautner, Victor-Felix; Hagel, Christian; Morrison, Helen

    2014-02-01

    Axonal surface proteins encompass a group of heterogeneous molecules, which exert a variety of different functions in the highly interdependent relationship between axons and Schwann cells. We recently revealed that the tumour suppressor protein merlin, mutated in the hereditary tumour syndrome neurofibromatosis type 2, impacts significantly on axon structure maintenance in the peripheral nervous system. We now report on a role of neuronal merlin in the regulation of the axonal surface protein neuregulin 1 important for modulating Schwann cell differentiation and myelination. Specifically, neuregulin 1 type III expression is reduced in sciatic nerve tissue of neuron-specific knockout animals as well as in biopsies from seven patients with neurofibromatosis type 2. In vitro experiments performed on both the P19 neuronal cell line and primary dorsal root ganglion cells demonstrate the influence of merlin on neuregulin 1 type III expression. Moreover, expression of ERBB2, a Schwann cell receptor for neuregulin 1 ligands is increased in nerve tissue of both neuron-specific merlin knockout animals and patients with neurofibromatosis type 2, demonstrating for the first time that axonal merlin indirectly regulates Schwann cell behaviour. Collectively, we have identified that neuronally expressed merlin can influence Schwann cell activity in a cell-extrinsic manner.

  3. Quantitation of the mRNA expression of the epidermal growth factor system: selective induction of heparin-binding epidermal growth factor-like growth factor and amphiregulin expression by growth factor stimulation of prostate stromal cells.

    Science.gov (United States)

    Sørensen, B S; Tørring, N; Bor, M V; Nexo, E

    2000-09-01

    The epidermal growth factor (EGF) system is a rapidly expanding system of growth factors involved in many aspects of normal and cancerous growth. We have developed a method for the quantitation of mRNA coding for all six growth factors activating the human EGF receptor (HER-1) and for the quantitation of mRNA for the receptors HER-1 and its preferred dimerization partner, HER-2. The method is based on the generation of specific RNA standards, which are amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) with the sample RNA and a set of calibrators. The resulting calibration curve is used to quantitate the unknown samples, which require only a single RT-PCR reaction. Our method has the advantage that quantitation is based on coamplification of an internal RNA standard, thereby controlling both the PCR and RT reactions. In addition, the RNA standards for all growth factors and receptors are combined in a single RT reaction, which minimizes variation and allows the quantitation of all eight mRNA species with only 0.1 microg RNA. This makes the method suitable for studies in which the supply of material is limited. The developed method has enabled us to demonstrate that prostate stromal cells in primary culture express EGF, heparin-binding EGF (HB-EGF), amphiregulin, betacellulin, and epiregulin as well as the HER-1 and HER-2 receptors, whereas no transforming growth factor-alpha mRNA is found. Furthermore, activation of the EGF system in these cells by stimulation with HB-EGF or EGF in mitogenic doses causes a selective increase in the expression of amphiregulin and HB-EGF mRNA (more than 15-fold and 25-fold, respectively), whereas there is no increase in the expression of mRNA for the other growth factors or receptors. In accord with the increase in amphiregulin mRNA, the amount of amphiregulin peptide released from the cells is also increased. The selective induction of amphiregulin and HB-EGF by growth factor stimulation may represent a mechanism

  4. Identification of heparin-binding EGF-like growth factor (HB-EGF as a biomarker for lysophosphatidic acid receptor type 1 (LPA1 activation in human breast and prostate cancers.

    Directory of Open Access Journals (Sweden)

    Marion David

    Full Text Available Lysophosphatidic acid (LPA is a natural bioactive lipid with growth factor-like functions due to activation of a series of six G protein-coupled receptors (LPA₁₋₆. LPA receptor type 1 (LPA₁ signaling influences the pathophysiology of many diseases including cancer, obesity, rheumatoid arthritis, as well as lung, liver and kidney fibrosis. Therefore, LPA₁ is an attractive therapeutic target. However, most mammalian cells co-express multiple LPA receptors whose co-activation impairs the validation of target inhibition in patients because of missing LPA receptor-specific biomarkers. LPA₁ is known to induce IL-6 and IL-8 secretion, as also do LPA₂ and LPA₃. In this work, we first determined the LPA induced early-gene expression profile in three unrelated human cancer cell lines expressing different patterns of LPA receptors (PC3: LPA₁,₂,₆; MDA-MB-231: LPA1,2; MCF-7: LPA₂,₆. Among the set of genes upregulated by LPA only in LPA₁-expressing cells, we validated by QPCR and ELISA that upregulation of heparin-binding EGF-like growth factor (HB-EGF was inhibited by LPA₁-₃ antagonists (Ki16425, Debio0719. Upregulation and downregulation of HB-EGF mRNA was confirmed in vitro in human MDA-B02 breast cancer cells stably overexpressing LPA₁ (MDA-B02/LPA₁ and downregulated for LPA₁ (MDA-B02/shLPA1, respectively. At a clinical level, we quantified the expression of LPA₁ and HB-EGF by QPCR in primary tumors of a cohort of 234 breast cancer patients and found a significantly higher expression of HB-EGF in breast tumors expressing high levels of LPA₁. We also generated human xenograph prostate tumors in mice injected with PC3 cells and found that a five-day treatment with Ki16425 significantly decreased both HB-EGF mRNA expression at the primary tumor site and circulating human HB-EGF concentrations in serum. All together our results demonstrate that HB-EGF is a new and relevant biomarker with potentially high value in

  5. Crystal Structure of the N-terminal Domain of the Group B Streptococcus Alpha C Protein

    Energy Technology Data Exchange (ETDEWEB)

    Auperin,T.; Bolduc, G.; Baron, M.; Heroux, A.; Filman, D.; Madoff, L.; Hogle, J.

    2005-01-01

    Group B Streptococcus (GBS) is the leading cause of bacterial pneumonia, sepsis, and meningitis among neonates and an important cause of morbidity among pregnant women and immunocompromised adults. Invasive diseases due to GBS are attributed to the ability of the pathogen to translocate across human epithelial surfaces. The alpha C protein (ACP) has been identified as an invasin that plays a role in internalization and translocation of GBS across epithelial cells. The soluble N-terminal domain of ACP (NtACP) blocks the internalization of GBS. We determined the 1.86-{angstrom} resolution crystal structure of NtACP comprising residues Ser{sup 52} through Leu{sup 225} of the full-length ACP. NtACP has two domains, an N-terminal {beta}-sandwich and a C-terminal three-helix bundle. Structural and topological alignments reveal that the {beta}-sandwich shares structural elements with the type III fibronectin fold (FnIII), but includes structural elaborations that make it unique. We have identified a potential integrin-binding motif consisting of Lys-Thr-Asp{sup 146}, Arg{sup 110}, and Asp{sup 118}. A similar arrangement of charged residues has been described in other invasins. ACP shows a heparin binding activity that requires NtACP. We propose a possible heparin-binding site, including one surface of the three-helix bundle, and nearby portions of the sandwich and repeat domains. We have validated this prediction using assays of the heparin binding and cell-adhesion properties of engineered fragments of ACP. This is the first crystal structure of a member of the highly conserved Gram-positive surface alpha-like protein family, and it will enable the internalization mechanism of GBS to be dissected at the atomic level.

  6. An Antibody That Locks HER3 in the Inactive Conformation Inhibits Tumor Growth Driven by HER2 or Neuregulin

    Energy Technology Data Exchange (ETDEWEB)

    Garner, A. P.; Bialucha, C. U.; Sprague, E. R.; Garrett, J. T.; Sheng, Q.; Li, S.; Sineshchekova, O.; Saxena, P.; Sutton, C. R.; Chen, D.; Chen, Y.; Wang, H.; Liang, J.; Das, R.; Mosher, R.; Gu, J.; Huang, A.; Haubst, N.; Zehetmeier, C.; Haberl, M.; Elis, W.; Kunz, C.; Heidt, A. B.; Herlihy, K.; Murtie, J.; Schuller, A.; Arteaga, C. L.; Sellers, W. R.; Ettenberg, S. A.

    2013-08-08

    HER2/HER3 dimerization resulting from overexpression of HER2 or neuregulin (NRG1) in cancer leads to HER3-mediated oncogenic activation of phosphoinositide 3-kinase (PI3K) signaling. Although ligand-blocking HER3 antibodies inhibit NRG1-driven tumor growth, they are ineffective against HER2-driven tumor growth because HER2 activates HER3 in a ligand-independent manner. In this study, we describe a novel HER3 monoclonal antibody (LJM716) that can neutralize multiple modes of HER3 activation, making it a superior candidate for clinical translation as a therapeutic candidate. LJM716 was a potent inhibitor of HER3/AKT phosphorylation and proliferation in HER2-amplified and NRG1-expressing cancer cells, and it displayed single-agent efficacy in tumor xenograft models. Combining LJM716 with agents that target HER2 or EGFR produced synergistic antitumor activity in vitro and in vivo. In particular, combining LJM716 with trastuzumab produced a more potent inhibition of signaling and cell proliferation than trastuzumab/pertuzumab combinations with similar activity in vivo. To elucidate its mechanism of action, we solved the structure of LJM716 bound to HER3, finding that LJM716 bound to an epitope, within domains 2 and 4, that traps HER3 in an inactive conformation. Taken together, our findings establish that LJM716 possesses a novel mechanism of action that, in combination with HER2- or EGFR-targeted agents, may leverage their clinical efficacy in ErbB-driven cancers.

  7. Transient overexposure of neuregulin 3 during early postnatal development impacts selective behaviors in adulthood.

    Directory of Open Access Journals (Sweden)

    Clare Paterson

    Full Text Available Neuregulin 3 (NRG3, a specific ligand for ErbB4 and a neuronal-enriched neurotrophin is implicated in the genetic predisposition to a broad spectrum of neurodevelopmental, neurocognitive and neuropsychiatric disorders, including Alzheimer's disease, autism and schizophrenia. Genetic studies in schizophrenia demonstrate that risk variants in NRG3 are associated with cognitive and psychotic symptom severity, accompanied by increased expression of prefrontal cortical NRG3. Despite our expanding knowledge of genetic involvement of NRG3 in neurological disorders, little is known about the neurodevelopmental mechanisms of risk. Here we exploited the fact that a paralog of NRG3, NRG1, readily penetrates the murine blood brain barrier (BBB. In this study we synthesized the bioactive epidermal growth factor (EGF domain of NRG3, and using previously validated in-vivo peripheral injection methodologies in neonatal mice, demonstrate that NRG3 successfully crosses the BBB, where it activates its receptor ErbB4 and downstream Akt signaling at levels of bioactivity comparable to NRG1. To determine the impact of NRG3 overexpression during one critical developmental window, C57BL/6 male mice were subcutaneously injected daily with NRG1-EGF, NRG3-EGF or vehicle from postnatal days 2-10. Mice were tested in adulthood using a comprehensive battery of behavioral tasks relevant to neurocognitive and psychiatric disorders. In agreement with previous studies, developmental overexposure to NRG1 induced multiple non-CNS mediated peripheral effects as well as severely disrupting performance of prepulse inhibition of the startle response. In contrast, NRG3 had no effect on any peripheral measures investigated or sensorimotor gating. Specifically, developmental NRG3 overexposure produced an anxiogenic-like phenotype and deficits in social behavior in adulthood. These results provide primary data to support a role for NRG3 in brain development and function, which appears to

  8. Circulating neuregulin 4 levels are inversely associated with subclinical cardiovascular disease in obese adults

    OpenAIRE

    Jie Jiang; Mingzhu Lin; Yanfang Xu; Jin Shao; Xuejun Li; Huijie Zhang; Shuyu Yang

    2016-01-01

    Neuregulin 4 (Nrg4) has been identified as a new secreted adipokine that may protect against development of obesity and metabolic disorders. However, information is not available regarding the association between circulating Nrg4 and subclinical atherosclerosis in humans. We measured serum Nrg4 in 485 obese adult subjects (aged 40 years or older) who had the measurement of carotid intima-media thickness (CIMT) recruited from the community. Individuals with increased CIMT and carotid plaque ha...

  9. Neuregulin repellent signaling via ErbB4 restricts GABAergic interneurons to migratory paths from ganglionic eminence to cortical destinations

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    Li Hao

    2012-02-01

    Full Text Available Abstract Background Cortical GABAergic interneurons (INs are generated in the medial ganglionic eminence (MGE and migrate tangentially into cortex. Because most, if not all, migrating MGE-derived INs express the neuregulin (NRG receptor, ErbB4, we investigated influences of Nrg1 isoforms and Nrg3 on IN migration through ventral telencephalon (vTel and within cortex. Results During IN migration, NRG expression domains and distributions of ErbB4-expressing, MGE-derived INs are complementary with minimal overlap, both in vTel and cortex. In wild-type mice, within fields of NRG expression, these INs are focused at positions of low or absent NRG expression. However, in ErbB4-/- HER4heart mutant mice in which INs lack ErbB4, these complementary patterns are degraded with considerable overlap evident between IN distribution and NRG expression domains. These findings suggest that NRGs are repellents for migrating ErbB4-expressing INs, a function supported by in vitro and in vivo experiments. First, in collagen co-cultures, MGE-derived cells preferentially migrate away from a source of secreted NRGs. Second, cells migrating from wild-type MGE explants on living forebrain slices from wild-type embryonic mice tend to avoid endogenous NRG expression domains, whereas this avoidance behavior is not exhibited by ErbB4-deficient cells migrating from MGE explants and instead they have a radial pattern with a more uniform distribution. Third, ectopic NRG expression in the IN migration pathway produced by in utero electroporation blocks IN migration and results in cortex distal to the blockade being largely devoid of INs. Finally, fewer INs reach cortex in ErbB4 mutants, indicating that NRG-ErbB4 signaling is required for directing IN migration from the MGE to cortex. Conclusions Our results show that NRGs act as repellents for migrating ErbB4-expressing, MGE-derived GABAergic INs and that the patterned expression of NRGs funnels INs as they migrate from the MGE

  10. Identification of a neuregulin and protein-tyrosine phosphatase response element in the nicotinic acetylcholine receptor epsilon subunit gene: regulatory role of an Rts transcription factor.

    Science.gov (United States)

    Sapru, M K; Florance, S K; Kirk, C; Goldman, D

    1998-02-03

    At the neuromuscular synapse, innervation induces endplate-specific expression of adult-type nicotinic acetylcholine receptors by selective expression of their subunit-encoding genes (alpha2betaepsilondelta) in endplate-associated myonuclei. These genes are specifically regulated by protein-tyrosine phosphatase (PTPase) activity. In addition, neuregulin/acetylcholine-receptor-inducing activity, a nerve-derived factor that stimulates nicotinic acetylcholine receptor synthesis, induces adult-type specific epsilon subunit gene expression via activation of a Ras/mitogen-activated protein kinase pathway. However, the DNA regulatory elements and the binding proteins that mediate PTPase and neuregulin-dependent gene expression remain unknown. Herein we report that PTPase, neuregulin, and Ras-dependent regulation of the epsilon subunit gene map to a 15-bp promoter sequence. Interestingly, this same 15-bp sequence appears to be necessary for low epsilon subunit gene expression in extrajunctional regions of the muscle fiber. Site-directed mutagenesis of a putative Ets binding site located within this 15-bp sequence, reduced PTPase, neuregulin, and Ras-dependent regulation. Overexpression of the rat muscle Ets-2 transcription factor resulted in a sequence-specific induction of epsilon subunit promoter activity. Further, a dominant negative mutant of Ets-2 abolished neuregulin-dependent induction of epsilon subunit gene expression. Thus, these results indicate a crucial role for the 15-bp element in determining synapse-specific and neuregulin-mediated motor neuron control of epsilon subunit gene expression and suggest the participation of Ets transcription factor(s) in this control.

  11. Behavioural characterization of neuregulin 1 (NRG1) type I over-expressing transgenic mice

    Science.gov (United States)

    Deakin, Inga H.; Law, Amanda J.; Oliver, Peter L.; Schwab, Markus H.; Nave, Klaus Armin; Harrison, Paul J.; Bannerman, David M.

    2009-01-01

    Neuregulin 1 (NRG1) is a pleiotropic growth factor involved in diverse aspects of brain development and function. In schizophrenia, expression of the NRG1 type I isoform is selectively increased. However, virtually nothing is known about the roles of this isoform in brain. We have studied transgenic mice over-expressing type I NRG1 (NRG1type 1-tg) using a series of behavioural tests. NRG1type 1-tg mice have a tremor, are impaired on the accelerating rotarod, and have reduced prepulse inhibition in the context of an increased baseline startle response. There is no overall anxiety or activity phenotype, although female NRG1type 1-tg mice show mild increases in anxiety on some measures. The pattern of results shows both similarities and differences to those reported in hypomorphic NRG1 mice, and may be relevant for interpreting the increased NRG1 type I expression seen in schizophrenia. PMID:19829162

  12. Neuregulin 3 Mediates Cortical Plate Invasion and Laminar Allocation of GABAergic Interneurons

    Directory of Open Access Journals (Sweden)

    Giorgia Bartolini

    2017-01-01

    Full Text Available Neural circuits in the cerebral cortex consist of excitatory pyramidal cells and inhibitory interneurons. These two main classes of cortical neurons follow largely different genetic programs, yet they assemble into highly specialized circuits during development following a very precise choreography. Previous studies have shown that signals produced by pyramidal cells influence the migration of cortical interneurons, but the molecular nature of these factors has remained elusive. Here, we identified Neuregulin 3 (Nrg3 as a chemoattractive factor expressed by developing pyramidal cells that guides the allocation of cortical interneurons in the developing cortical plate. Gain- and loss-of-function approaches reveal that Nrg3 modulates the migration of interneurons into the cortical plate in a process that is dependent on the tyrosine kinase receptor ErbB4. Perturbation of Nrg3 signaling in conditional mutants leads to abnormal lamination of cortical interneurons. Nrg3 is therefore a critical mediator in the assembly of cortical inhibitory circuits.

  13. The roles of neuregulin-1 in cardiac development, homeostasis, and disease.

    Science.gov (United States)

    Rupert, Cassady E; Coulombe, Kareen Lk

    2015-01-01

    Neuregulin-1 (NRG-1) and its signaling receptors, erythroblastic leukemia viral oncogene homologs (ErbB) 2, 3, and 4, have been implicated in both cardiomyocyte development and disease, as well as in homeostatic cardiac function. NRG-1/ErbB signaling is involved in a multitude of cardiac processes ranging from myocardial and cardiac conduction system development to angiogenic support of cardiomyocytes, to cardioprotective effects upon injury. Numerous studies of NRG-1 employ a variety of platforms, including in vitro assays, animal models, and human clinical trials, with equally varying and, sometimes, contradictory outcomes. NRG-1 has the potential to be used as a therapeutic tool in stem cell therapies, tissue engineering applications, and clinical diagnostics and treatment. This review presents a concise summary of the growing body of literature to highlight the temporally persistent significance of NRG-1/ErbB signaling throughout development, homeostasis, and disease in the heart, specifically in cardiomyocytes.

  14. Inside-out Regulation of Ectodomain Cleavage of Cluster-of-Differentiation-44 (CD44) and of Neuregulin-1 Requires Substrate Dimerization.

    Science.gov (United States)

    Hartmann, Monika; Parra, Liseth M; Ruschel, Anne; Lindner, Christina; Morrison, Helen; Herrlich, Andreas; Herrlich, Peter

    2015-07-10

    Ectodomain shedding of transmembrane precursor proteins generates numerous life-essential molecules, such as epidermal growth factor receptor ligands. This cleavage not only releases the regulatory growth factor, but it is also the required first step for the subsequent processing by γ-secretase and the release of gene regulatory intracellular fragments. Signaling within the cell modifies the cytoplasmic tails of substrates, a step important in starting the specific and regulated cleavage of a large number of studied substrates. Ectodomain cleavage occurs, however, on the outside of the plasma membrane and is carried out by membrane-bound metalloproteases. How the intracellular domain modification communicates with the ectodomain of the substrate to allow for cleavage to occur is unknown. Here, we show that homodimerization of a cluster-of-differentiation-44 or of pro-neuregulin-1 monomers represents an essential pre-condition for their regulated ectodomain cleavage. Both substrates are associated with their respective metalloproteases under both basal or cleavage-stimulated conditions. These interactions only turn productive by specific intracellular signal-induced intracellular domain modifications of the substrates, which in turn regulate metalloprotease access to the substrates' ectodomain and cleavage. We propose that substrate intracellular domain modification induces a relative rotation or other positional change of the dimerization partners that allow metalloprotease cleavage in the extracellular space. Our findings fill an important gap in understanding substrate-specific inside-out signal transfer along cleaved transmembrane proteins and suggest that substrate dimerization (homo- or possibly heterodimerization) might represent a general principle in ectodomain shedding. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Identification of diphtheria toxin R domain mutants with enhanced inhibitory activity against HB-EGF.

    Science.gov (United States)

    Suzuki, Keisuke; Mizushima, Hiroto; Abe, Hiroyuki; Iwamoto, Ryo; Nakamura, Haruki; Mekada, Eisuke

    2015-05-01

    Heparin-binding epidermal growth factor-like growth factor (HB-EGF), a ligand of EGF receptor, is involved in the growth and malignant progression of cancers. Cross-reacting material 197, CRM197, a non-toxic mutant of diphtheria toxin (DT), specifically binds to the EGF-like domain of HB-EGF and inhibits its mitogenic activity, thus CRM197 is currently under evaluation in clinical trials for cancer therapy. To develop more potent DT mutants than CRM197, we screened various mutant proteins of R domain of DT, the binding site for HB-EGF. A variety of R-domain mutant proteins fused with maltose-binding protein were produced and their inhibitory activity was evaluated in vitro. We found four R domain mutants that showed much higher inhibitory activity against HB-EGF than wild-type (WT) R domain. These R domain mutants suppressed HB-EGF-dependent cell proliferation more effectively than WT R domain. Surface plasmon resonance revealed their higher affinity to HB-EGF than WT R domain. CRM197(R460H) carrying the newly identified mutation showed increased cell proliferation inhibitory activity and affinity to HB-EGF. These results suggest that CRM197(R460H) or other recombinant proteins carrying newly identified mutation(s) in the R domain are potential therapeutics targeting HB-EGF. © The Authors 2014. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  16. What does a mouse tell us about neuregulin 1 – cannabis interactions?

    Directory of Open Access Journals (Sweden)

    Tim eKarl

    2013-02-01

    Full Text Available The link between cannabis and psychosis has been debated although there is substantial epidemiological evidence showing that cannabis increases the risk of psychosis. It has been hypothesized that schizophrenia patients carrying particular risk genes might be more sensitive to the psychosis-inducing effects of cannabis than other patients and healthy test subjects. Here we review the effects of cannabinoids on a mutant mouse model for the schizophrenia candidate gene neuregulin 1 (Nrg1. The studies suggest a complex interaction between cannabis and Nrg1: the neuro-behavioural effects of cannabinoids were different in Nrg1 mutant and control mice and depended on exposure time, sex and age of test animals. This research provides the first evidence of complex cannabis-Nrg1 interactions suggesting Nrg1 as a prime target for future clinical investigations. Furthermore, it highlights that animal model research can broaden our understanding of the complex multi-factorial aetiology of schizophrenia. Finally, the findings are important to preventive psychiatry: if the genes that confer genetic vulnerability to cannabis-induced psychosis were identified patients at-high risk could be forewarned of the potential dangers of cannabis abuse.

  17. Inhibition of endoplasmic reticulum stress by neuregulin-1 protects against myocardial ischemia/reperfusion injury.

    Science.gov (United States)

    Fang, Shan-Juan; Li, Peng-Yang; Wang, Chun-Mei; Xin, Yi; Lu, Wei-Wei; Zhang, Xiao-Xia; Zuo, Song; Ma, Chang-Sheng; Tang, Chao-Shu; Nie, Shao-Ping; Qi, Yong-Fen

    2017-02-01

    Neuregulin-1 (NRG-1), an endogenously produced polypeptide, is the ligand of cardiomyocyte ErbB receptors, with cardiovascular protective effects. In the present study, we explored whether the cardioprotective effect of NRG-1 against I/R injury is mediated by inhibiting myocardial endoplasmic reticulum (ER) stress. In vitro, NRG-1 directly inhibited the upregulation of ER stress markers such as glucose-regulated protein 78, CCAAT/enhancer binding protein homologous protein and cleaved caspase-12 induced by the ER stress inducers tunicamycin or dithiothreitol in both neonatal and adult ventricular myocytes. Attenuating ErbB signals by an ErbB inhibitor AG1478 or ErbB4 knockdown and preincubation with phosphoinositide 3-kinase inhibitors all reversed the effect of NRG-1 inhibiting ER stress in cultured neonatal rat cardiomyocytes. Concurrently, cardiomyocyte ER stress and apoptosis induced by hypoxia-reoxygenation were decreased by NRG-1 treatment in vitro. Furthermore, in an in vivo rat model of myocardium ischemia/reperfusion (I/R), intravenous NRG-1 administration significantly decreased ER stress and myocardial infarct size induced by I/R. NRG-1 could protect the heart against I/R injury by inhibiting myocardial ER stress, which might be mediated by the phosphoinositide 3-kinase/Akt signaling pathway. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Plasma soluble neuregulin-1 as a diagnostic biomarker for Alzheimer's disease.

    Science.gov (United States)

    Chang, Keun-A; Shin, Ki Young; Nam, Eunjoo; Lee, Yeong-Bae; Moon, Cheil; Suh, Yoo-Hun; Lee, Sang Hyung

    2016-07-01

    To identify some apparent biomarker candidates for the diagnosis of Alzheimer's disease (AD) pathology, we investigated whether there would be a significant difference between the levels of the plasma proteins of AD patients and healthy people. A total of 115 subjects were enrolled, 60 individuals with AD and 55 healthy controls. There was a statistical difference in the mini-mental status exam (MMSE) scores and the clinical dementia rating (CDR) scores between the two groups. We used the immunoblotting assay to analyze several plasma proteins in the subjects. Amyloid-β (Aβ), S100a9, and soluble neuregulin-1 (sNRG-1), including α-synuclein (α-Syn) as a detection control were detected in the plasma samples. Unlike Aβ, S100a9 and α-Syn, the level of sNRG-1 of the AD patients was significantly higher than that of the healthy control subjects. The AD patients were divided into mild and moderate groups according to their MMSE and CDR scores. We found a significant correlation between the level of sNRG-1 and MMSE scores. The sNRG-1 level was significantly higher in mild AD patients as well as in moderate AD patients compared with that of the control subjects. These new findings indicate that increased plasma sNRG-1 levels might be a novel and reliable biological marker for the early diagnosis of AD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Neuregulin 1 Promotes Glutathione-Dependent Neuronal Cobalamin Metabolism by Stimulating Cysteine Uptake

    Directory of Open Access Journals (Sweden)

    Yiting Zhang

    2016-01-01

    Full Text Available Neuregulin 1 (NRG-1 is a key neurotrophic factor involved in energy homeostasis and CNS development, and impaired NRG-1 signaling is associated with neurological disorders. Cobalamin (Cbl, also known as vitamin B12, is an essential micronutrient which mammals must acquire through diet, and neurologic dysfunction is a primary clinical manifestation of Cbl deficiency. Here we show that NRG-1 stimulates synthesis of the two bioactive Cbl species adenosylcobalamin (AdoCbl and methylcobalamin (MeCbl in human neuroblastoma cells by both promoting conversion of inactive to active Cbl species and increasing neuronal Cbl uptake. Formation of active Cbls is glutathione- (GSH- dependent and the NRG-1-initiated increase is dependent upon its stimulation of cysteine uptake by excitatory amino acid transporter 3 (EAAT3, leading to increased GSH. The stimulatory effect of NRG-1 on cellular Cbl uptake is associated with increased expression of megalin, which is known to facilitate Cbl transport in ileum and kidney. MeCbl is a required cofactor for methionine synthase (MS and we demonstrate the ability of NRG-1 to increase MS activity, and affect levels of methionine methylation cycle metabolites. Our results identify novel neuroprotective roles of NRG-1 including stimulating antioxidant synthesis and promoting active Cbl formation.

  20. Epistatic and functional interactions of catechol-o-methyltransferase (COMT and AKT1 on neuregulin1-ErbB signaling in cell models.

    Directory of Open Access Journals (Sweden)

    Yoshitatsu Sei

    2010-05-01

    Full Text Available Neuregulin1 (NRG1-ErbB signaling has been implicated in the pathogenesis of cancer and schizophrenia. We have previously reported that NRG1-stimulated migration of B lymphoblasts is PI3K-AKT1dependent and impaired in patients with schizophrenia and significantly linked to the catechol-o-methyltransferase (COMT Val108/158Met functional polymorphism.We have now examined AKT1 activation in NRG1-stimulated B lymphoblasts and other cell models and explored a functional relationship between COMT and AKT1. NRG1-induced AKT1 phosphorylation was significantly diminished in Val carriers compared to Met carriers in both normal subjects and in patients. Further, there was a significant epistatic interaction between a putatively functional coding SNP in AKT1 (rs1130233 and COMT Val108/158Met genotype on AKT1 phosphorylation. NRG1 induced translocation of AKT1 to the plasma membrane also was impaired in Val carriers, while PIP(3 levels were not decreased. Interestingly, the level of COMT enzyme activity was inversely correlated with the cells' ability to synthesize phosphatidylserine (PS, a factor that attracts the pleckstrin homology domain (PHD of AKT1 to the cell membrane. Transfection of SH-SY5Y cells with a COMT Val construct increased COMT activity and significantly decreased PS levels as well as NRG1-induced AKT1 phosphorylation and migration. Administration of S-adenosylmethionine (SAM rescued all of these deficits. These data suggest that AKT1 function is influenced by COMT enzyme activity through competition with PS synthesis for SAM, which in turn dictates AKT1-dependent cellular responses to NRG1-mediated signaling.Our findings implicate genetic and functional interactions between COMT and AKT1 and may provide novel insights into pathogenesis of schizophrenia and other ErbB-associated human diseases such as cancer.

  1. No significant association of the 5' end of neuregulin 1 and schizophrenia in a large Danish sample

    DEFF Research Database (Denmark)

    Ingason, Andrés; Søeby, Karen; Timm, Sally

    2006-01-01

    schizophrenia patients. We found that the at-risk haplotype initially reported in the Icelandic population was not found in significant excess (or = 1.4, p = 0.12). The haplotype structure in the Danish sample was similar to that of other reported in other Caucasian populations and highly different from......Neuregulin 1 has been implicated as a susceptibility gene in schizophrenia. Several research groups have reported association with the 5' end of the gene although no causative variant has been reported. We have investigated whether there is association with the 5' end of the gene in Danish...

  2. Perinatal phencyclidine administration decreases the density of cortical interneurons and increases the expression of neuregulin-1.

    Science.gov (United States)

    Radonjić, Nevena V; Jakovcevski, Igor; Bumbaširević, Vladimir; Petronijević, Nataša D

    2013-06-01

    Perinatal phencyclidine (PCP) administration in rat blocks the N-methyl D-aspartate receptor (NMDAR) and causes symptoms reminiscent of schizophrenia in human. A growing body of evidence suggests that alterations in γ-aminobutyric acid (GABA) interneuron neurotransmission may be associated with schizophrenia. Neuregulin-1 (NRG-1) is a trophic factor important for neurodevelopment, synaptic plasticity, and wiring of GABA circuits. The aim of this study was to determine the long-term effects of perinatal PCP administration on the projection and local circuit neurons and NRG-1 expression in the cortex and hippocampus. Rats were treated on postnatal day 2 (P2), P6, P9, and P12 with either PCP (10 mg/kg) or saline. Morphological studies and determination of NRG-1 expression were performed at P70. We demonstrate reduced densities of principal neurons in the CA3 and dentate gyrus (DG) subregions of the hippocampus and a reduction of major interneuronal populations in all cortical and hippocampal regions studied in PCP-treated rats compared with controls. For the first time, we show the reduced density of reelin- and somatostatin-positive cells in the cortex and hippocampus of animals perinatally treated with PCP. Furthermore, an increase in the numbers of perisomatic inhibitory terminals around the principal cells was observed in the motor cortex and DG. We also show that perinatal PCP administration leads to an increased NRG-1 expression in the cortex and hippocampus. Taken together, our findings demonstrate that perinatal PCP administration increases NRG-1 expression and reduces the number of projecting and local circuit neurons, revealing complex consequences of NMDAR blockade.

  3. Proteomic analysis of heparin-binding proteins from human seminal ...

    Indian Academy of Sciences (India)

    Prakash

    capacitation in the female reproductive tract is aided by. HBPs secreted by the male accessory sex glands (Miller et al. 1990). Seminal fluid HBPs are supposed to attach themselves to the sperm surface, especially lipids containing the phosphoryl-choline group, thus allowing heparin-like. GAGs in the female reproductive ...

  4. hMPV Lineage Nomenclature and Heparin Binding

    Directory of Open Access Journals (Sweden)

    David Gordon

    2013-10-01

    Full Text Available Human metapneumovirus (hMPV, first described in 2001 [1], is responsible for causing serious respiratory illness in young children, the elderly and immunocompromised patients. Four distinct lineages of hMPV have been identified with the original nomenclature for these subgroups (A1, A2, B1 and B2, reported by van den Hoogen et al. [2], utilised by many. An alternate terminology (1A, 1B, 2A and 2B was also published by Ishiguro et al. in 2004 [3] which has been adopted by others. However, this has caused some confusion in the interpretation of publication results as the terminology is similar yet describes different subtypes. As a result, a number of investigators have made a submission to the International Committee on Taxonomy of Viruses (ICTV, ICTV taxonomic proposal 2012.012V for the official adoption of the original terminology as an approved nomenclature for hMPV [4]. We welcome this officially approved nomenclature which should provide clarification of these subtypes in future. Therefore to assist with the interpretation of our recently published research in the 2012 special issue of Viruses: Pneumoviruses and Metapneumoviruses entitled “Diversity in Glycosaminoglycan Binding Amongst hMPV G Protein Lineages” [5] we have updated the Figure 3 in this letter (see Figure 1, showing the proposed ICTV terminology compared to the Ishiguro classification (used in our publication. Note that in the original publication the alphanumeric order for the Ishiguro classification was transposed (e.g., 1A was referred to as A1.

  5. Active G protein-coupled receptors (GPCR), matrix metalloproteinases 2/9 (MMP2/9), heparin-binding epidermal growth factor (hbEGF), epidermal growth factor receptor (EGFR), erbB2, and insulin-like growth factor 1 receptor (IGF-1R) are necessary for trenbolone acetate-induced alterations in protein turnover rate of fused bovine satellite cell cultures.

    Science.gov (United States)

    Thornton, K J; Kamanga-Sollo, E; White, M E; Dayton, W R

    2016-06-01

    Trenbolone acetate (TBA), a testosterone analog, increases protein synthesis and decreases protein degradation in fused bovine satellite cell (BSC) cultures. However, the mechanism through which TBA alters these processes remains unknown. Recent studies indicate that androgens improve rate and extent of muscle growth through a nongenomic mechanism involving G protein-coupled receptors (GPCR), matrix metalloproteinases (MMP), heparin-binding epidermal growth factor (hbEGF), the epidermal growth factor receptor (EGFR), erbB2, and the insulin-like growth factor-1 receptor (IGF-1R). We hypothesized that TBA activates GPCR, resulting in activation of MMP2/9 that releases hbEGF, which activates the EGFR and/or erbB2. To determine whether the proposed nongenomic pathway is involved in TBA-mediated alterations in protein turnover, fused BSC cultures were treated with TBA in the presence or absence of inhibitors for GPCR, MMP2/9, hbEGF, EGFR, erbB2, or IGF-1R, and resultant protein synthesis and degradation rates were analyzed. Assays were replicated at least 9 times for each inhibitor experiment utilizing BSC cultures obtained from at least 3 different steers that had no previous exposure to steroid compounds. As expected, fused BSC cultures treated with 10 n TBA exhibited increased ( GPCR, MMP2/9, hbEGF, EGFR, erbB2, or IGF-1R suppressed ( GPCR, MMP2/9, hbEGF, EGFR, erbB2, or IGF-1R in the presence of 10 n TBA each had no ( > 0.05) effect on TBA-mediated decreases in protein degradation. However, inhibition of both EGFR and erbB2 in the presence of 10 n TBA resulted in decreased ( GPCR, MMP2/9, hbEGF, EGFR, erbB2, and IGF-1R. However, the mechanism through which TBA mediates changes in protein degradation is different and appears to involve only the EGFR and erbB2. Furthermore, it appears the protein kinase B pathway is involved in TBA's effects on fused BSC cultures.

  6. Interactions among genes in the ErbB-Neuregulin signalling network are associated with increased susceptibility to schizophrenia

    Directory of Open Access Journals (Sweden)

    McGinnis Ralph

    2007-06-01

    Full Text Available Abstract Background Evidence of genetic association between the NRG1 (Neuregulin-1 gene and schizophrenia is now well-documented. Furthermore, several recent reports suggest association between schizophrenia and single-nucleotide polymorphisms (SNPs in ERBB4, one of the receptors for Neuregulin-1. In this study, we have extended the previously published associations by investigating the involvement of all eight genes from the ERBB and NRG families for association with schizophrenia. Methods Eight genes from the ERBB and NRG families were tested for association to schizophrenia using a collection of 396 cases and 1,342 blood bank controls ascertained from Aberdeen, UK. A total of 365 SNPs were tested. Association testing of both alleles and genotypes was carried out using the fast Fisher's Exact Test (FET. To understand better the nature of the associations, all pairs of SNPs separated by ≥ 0.5 cM with at least nominal evidence of association (P Results 42 out of 365 tested SNPs in the eight genes from the ERBB and NRG gene families were significantly associated with schizophrenia (P Conclusion These new findings suggest that observed associations between NRG1 and schizophrenia may be mediated through functional interaction not just with ERBB4, but with other members of the NRG and ERBB families. There is evidence that genetic interaction among these loci may increase susceptibility to schizophrenia.

  7. SNP8NRG433E1006 NEUREGULIN-1 GENETIC VARIATION IN BATAKS ETHNIC WITH SCHIZOPHRENIA PARANOID AND HEALTHY CONTROL

    Directory of Open Access Journals (Sweden)

    Elmeida Effendy

    2014-05-01

    Full Text Available The neuregulin 1 (NRG1 gene which influences the development of white matter connectivity has been associated with schizophrenia. It influences neuronal migration, synaptogenesis, gliogenesis, neuron-glia communication, myelination, and neurotransmission in the brain and others. NRG1 is located in 8p13, and it is frequently replicated in schizphrenia. SNP8NRG433E1006 gene NRG1 is one of core at risk haplotype of schizphrenia. This study looked forward differences SNP8NRG433E1006 neuregulin 1 between Bataks ethnic with schizophrenia paranoid and Bataks ethnic healthy control. Methods: Batak ethnic with schizophrenia paranoid were recruited and interviewed with semi-structured MINI ICD-X to establish the diagnosis. All the eligible subjects were requested their permission for blood sampling. Healthy Batak ethnic were also recruited by mathcing the age and gender. The blood samples went through DNA isolation, Nested PCR, and DNA sequencing. Results: Ninety three subjects were recruited, but only 74 blood samples were succesfully sequenced. We found three types of polymorphisms, i.e. G/A allele at base pair (bp 76, G/T allele at bp 112, and deletion at bp 110 in Batak ethnic with schizophrenia. There were two kind sequences at bp 113-116 in Batak ethnics, and Batak ethnics with ATCG were at higher risk for having schizophrenia. This study support that NRG1 is a schizophrenia-susceptibility gene.

  8. Characterization of E3 ubiquitin ligase neuregulin receptor degradation protein-1 (Nrdp1) in the large yellow croaker (Larimichthys crocea) and its immune responses to Cryptocaryon irritans.

    Science.gov (United States)

    Zhang, Dong Ling; Han, Fang; Yu, Da Hui; Xiao, Shi Jun; Li, Ming Yun; Chen, Jian; Wang, Zhi Yong

    2015-02-10

    Neuregulin receptor degradation protein-1 (Nrdp1) was recently identified in humans as an important immune factor responding to the challenge of virus, LPS or cytokine. Its role in fish immune defense and whether it is involved in anti-parasite immunity have not been proven yet. In this report, the full-length cDNA sequence and genomic structure of Nrdp1 in the large yellow croaker Larimichthys crocea (LcNrdp1) were identified and characterized. The full-length cDNA of LcNrdp1 was 1248bp, including a 5' untranslated region (UTR) of 32bp, a 3' UTR of 259bp and an open reading frame (ORF) of 937bp, encoding a polypeptide of 318 amino acid residues. The full-length genomic DNA sequence of LcNrdp1 was composed of 2635 nucleotides, including four exons and three introns. The putative LcNrdp1 protein had no signal peptide sequence and contained a characteristic Nrdp1 consensus motif C3HC3D ring finger and a Coiled-coil domain. Phylogenetic analysis showed that Nrdp1 in fish was closer with that in other vertebrates (79%-90% amino acid identity) than in invertebrates and bacteria (27%-65%). In fishes, Nrdp1 in large yellow croaker was closer with that in Takifugu rubripes. The expression profile showed that LcNrdp1 was constitutively expressed in all tested tissues, especially highly expressed in brain, muscle and kidney. Post-infection (PI) with Cryptocaryon irritans, an increased expression of LcNrdp1 was induced in infection sites (skin and gill), whereas in immune organs, the expression of LcNrdp1 was up-regulated in spleen (except the 1st d and 10th d PI) but suppressed in head kidney. These results suggested that LcNrdp1 might play an important immune role in the finfish L. crocea in the defense against the parasite C. irritans. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Tenascin C promiscuously binds growth factors via its fifth fibronectin type III-like domain.

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    Laura De Laporte

    Full Text Available Tenascin C (TNC is an extracellular matrix protein that is upregulated during development as well as tissue remodeling. TNC is comprised of multiple independent folding domains, including 15 fibronectin type III-like (TNCIII domains. The fifth TNCIII domain (TNCIII5 has previously been shown to bind heparin. Our group has shown that the heparin-binding fibronectin type III domains of fibronectin (FNIII, specifically FNIII12-14, possess affinity towards a large number of growth factors. Here, we show that TNCIII5 binds growth factors promiscuously and with high affinity. We produced recombinant fragments of TNC representing the first five TNCIII repeats (TNCIII1-5, as well as subdomains, including TNCIII5, to study interactions with various growth factors. Multiple growth factors of the platelet-derived growth factor (PDGF family, the fibroblast growth factor (FGF family, the transforming growth factor beta (TGF-β superfamily, the insulin-like growth factor binding proteins (IGF-BPs, and neurotrophins were found to bind with high affinity to this region of TNC, specifically to TNCIII5. Surface plasmon resonance was performed to analyze the kinetics of binding of TNCIII1-5 with TGF-β1, PDGF-BB, NT-3, and FGF-2. The promiscuous yet high affinity of TNC for a wide array of growth factors, mediated mainly by TNCIII5, may play a role in multiple physiological and pathological processes involving TNC.

  10. Neuregulin-1 Administration Protocols Sufficient for Stimulating Cardiac Regeneration in Young Mice Do Not Induce Somatic, Organ, or Neoplastic Growth.

    Directory of Open Access Journals (Sweden)

    Balakrishnan Ganapathy

    Full Text Available We previously developed and validated a strategy for stimulating heart regeneration by administration of recombinant neuregulin (rNRG1, a growth factor, in mice. rNRG1 stimulated proliferation of heart muscle cells, cardiomyocytes, and was most effective when administration began during the neonatal period. Our results suggested the use of rNRG1 to treat pediatric patients with heart failure. However, administration in this age group may stimulate growth outside of the heart.NRG1 and ErbB receptor expression was determined by RT-PCR. rNRG1 concentrations in serum were quantified by ELISA. Mice that received protocols of recombinant neuregulin1-β1 administration (rNRG1, 100 ng/g body weight, daily subcutaneous injection for the first month of life, previously shown to induce cardiac regeneration, were examined at pre-determined intervals. Somatic growth was quantified by weighing. Organ growth was quantified by MRI and by weighing. Neoplastic growth was examined by MRI, visual inspection, and histopathological analyses. Phospho-ERK1/2 and S6 kinase were analyzed with Western blot and ELISA, respectively.Lung, spleen, liver, kidney, brain, and breast gland exhibited variable expression of the NRG1 receptors ErbB2, ErbB3, ErbB4, and NRG1. Body weight and tibia length were not altered in mice receiving rNRG1. MRI showed that administration of rNRG1 did not alter the volume of the lungs, liver, kidneys, brain, or spinal cord. Administration of rNRG1 did not alter the weight of the lungs, spleen, liver, kidneys, or brain. MRI, visual inspection, and histopathological analyses showed no neoplastic growth. Follow-up for 6 months showed no alteration of somatic or organ growth. rNRG1 treatment increased the levels of phospho-ERK1/2, but not phospho-S6 kinase.Administration protocols of rNRG1 for stimulating cardiac regeneration in mice during the first month of life did not induce unwanted growth effects. Further studies may be required to determine

  11. Stimulation of cardiomyocyte regeneration in neonatal mice and in human myocardium with neuregulin reveals a therapeutic window

    Science.gov (United States)

    Polizzotti, Brian D.; Ganapathy, Balakrishnan; Walsh, Stuart; Choudhury, Sangita; Ammanamanchi, Niyatie; Bennett, David G.; dos Remedios, Cristobal G.; Haubner, Bernhard J.; Penninger, Josef M.; Kuhn, Bernhard

    2015-01-01

    Background Pediatric patients with heart failure are treated with medical therapies that were developed for adult patients. These therapies have been shown to be ineffective in pediatric trials, leading to the recognition that new pediatric-specific therapies must be developed. We have previously shown that administration of the recombinant growth factor neuregulin-1 (rNRG1) stimulates heart muscle cell (cardiomyocyte) regeneration in adult mice. We hypothesized that rNRG1 administration may be more effective in the neonatal period, which could provide a new therapeutic paradigm for treating heart failure in pediatric patients. Methods We used a cryoinjury model to induce myocardial dysfunction and scar formation for evaluating the effectiveness of rNRG1-administration in neonatal mice. We evaluated the ability of rNRG1 to stimulate cardiomyocyte proliferation in intact cultured myocardium from pediatric patients. Results After cryoinjury in neonatal mice, early administration of rNRG1 from birth for 34 days improved myocardial function and reduced the prevalence of transmural scars. In contrast, late administration of rNRG1 from 4 to 34 days after cryoinjury transiently improved myocardial function. The mechanisms of early administration involved cardiomyocyte protection (38%) and proliferation (62%). rNRG1 induced cardiomyocyte proliferation in myocardium from infants with heart disease less than 6 months of age. Conclusion Our results identify a more effective time period within which to execute future clinical trials of rNRG1 for stimulating cardiomyocyte regeneration. PMID:25834111

  12. Neuregulin1 displayed on motor axons regulates terminal Schwann cell-mediated synapse elimination at developing neuromuscular junctions

    Science.gov (United States)

    Li, Yue; Mikesh, Michelle; Smith, Ian; Nave, Klaus-Armin; Schwab, Markus H.; Thompson, Wesley J.

    2016-01-01

    Synaptic connections in the nervous system are rearranged during development and in adulthood as a feature of growth, plasticity, aging, and disease. Glia are implicated as active participants in these changes. Here we investigated a signal that controls the participation of peripheral glia, the terminal Schwann cells (SCs), at the neuromuscular junction (NMJ) in mice. Transgenic manipulation of the levels of membrane-tethered neuregulin1 (NRG1-III), a potent activator of SCs normally presented on motor axons, alters the rate of loss of motor inputs at NMJs during developmental synapse elimination. In addition, NMJs of adult transgenic mice that expressed excess axonal NRG1-III exhibited continued remodeling, in contrast to the more stable morphologies of controls. In fact, synaptic SCs of these adult mice with NRG1-III overexpression exhibited behaviors evident in wild type neonates during synapse elimination, including an affinity for the postsynaptic myofiber surface and phagocytosis of nerve terminals. Given that levels of NRG1-III expression normally peak during the period of synapse elimination, our findings identify axon-tethered NRG1 as a molecular determinant for SC-driven neuromuscular synaptic plasticity. PMID:26755586

  13. Neuregulin1 displayed on motor axons regulates terminal Schwann cell-mediated synapse elimination at developing neuromuscular junctions.

    Science.gov (United States)

    Lee, Young Il; Li, Yue; Mikesh, Michelle; Smith, Ian; Nave, Klaus-Armin; Schwab, Markus H; Thompson, Wesley J

    2016-01-26

    Synaptic connections in the nervous system are rearranged during development and in adulthood as a feature of growth, plasticity, aging, and disease. Glia are implicated as active participants in these changes. Here we investigated a signal that controls the participation of peripheral glia, the terminal Schwann cells (SCs), at the neuromuscular junction (NMJ) in mice. Transgenic manipulation of the levels of membrane-tethered neuregulin1 (NRG1-III), a potent activator of SCs normally presented on motor axons, alters the rate of loss of motor inputs at NMJs during developmental synapse elimination. In addition, NMJs of adult transgenic mice that expressed excess axonal NRG1-III exhibited continued remodeling, in contrast to the more stable morphologies of controls. In fact, synaptic SCs of these adult mice with NRG1-III overexpression exhibited behaviors evident in wild type neonates during synapse elimination, including an affinity for the postsynaptic myofiber surface and phagocytosis of nerve terminals. Given that levels of NRG1-III expression normally peak during the period of synapse elimination, our findings identify axon-tethered NRG1 as a molecular determinant for SC-driven neuromuscular synaptic plasticity.

  14. Partial genetic deletion of neuregulin 1 and adolescent stress interact to alter NMDA receptor binding in the medial prefrontal cortex

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    Tariq Waseem Chohan

    2014-09-01

    Full Text Available Schizophrenia is thought to arise due to a complex interaction between genetic and environmental factors during early neurodevelopment. We have recently shown that partial genetic deletion of the schizophrenia susceptibility gene neuregulin 1 (Nrg1 and adolescent stress interact to disturb sensorimotor gating, neuroendocrine activity and dendritic morphology in mice. Both stress and Nrg1 may have converging effects upon N-methyl-D-aspartate receptors (NMDARs which are implicated in the pathogenesis of schizophrenia, sensorimotor gating and dendritic spine plasticity. Using an identical repeated restraint stress paradigm to our previous study, here we determined NMDAR binding across various brain regions in adolescent Nrg1 heterozygous (HET and wild-type (WT mice using [3H] MK-801 autoradiography. Repeated restraint stress increased NMDAR binding in the ventral part of the lateral septum (LSV and the dentate gyrus (DG of the hippocampus irrespective of genotype. Partial genetic deletion of Nrg1 interacted with adolescent stress to promote an altered pattern of NMDAR binding in the infralimbic (IL subregion of the medial prefrontal cortex. In the IL, whilst stress tended to increase NMDAR binding in WT mice, it decreased binding in Nrg1 HET mice. However in the DG, stress selectively increased the expression of NMDAR binding in Nrg1 HET mice but not WT mice. These results demonstrate a Nrg1-stress interaction during adolescence on NMDAR binding in the medial prefrontal cortex.

  15. Cooperative interaction of hepatocyte growth factor and neuregulin regulates Schwann cell migration and proliferation through Grb2-associated binder-2 in peripheral nerve repair.

    Science.gov (United States)

    Shin, Yoon Kyoung; Jang, So Young; Yun, Seoug Hoon; Choi, Yun Young; Yoon, Byeol-A; Jo, Young Rae; Park, So Young; Pak, Min Gyoung; Park, Joo In; Park, Hwan Tae

    2017-11-01

    The sequential reactive changes in Schwann cell phenotypes in transected peripheral nerves, including dedifferentiation, proliferation and migration, are essential for nerve repair. Even though the injury-induced migratory and proliferative behaviors of Schwann cells resemble epithelial and mesenchymal transition (EMT) in tumors, the molecular mechanisms underlying this phenotypic change of Schwann cells are still unclear. Here we show that the reactive Schwann cells exhibit migratory features dependent on the expression of a scaffolding oncoprotein Grb2-associated binder-2 (Gab2), which was transcriptionally induced by neuregulin 1-ErbB2 signaling following nerve injury. Injury-induced Gab2 expression was dependent on c-Jun, a transcription factor critical to a Schwann cell reprograming into a repair-type cell. Interestingly, the injury-induced activation (tyrosine phosphorylation) of Gab2 in Schwann cells was regulated by an EMT signal, the hepatocyte growth factor-c-Met signaling, but not by neuregulin 1. Gab2 knockout mice exhibited a deficit in nerve repair after nerve transection due to limited Schwann cell migration. Furthermore, Gab2 was required for the proliferation of Schwann cells following nerve injury and in vitro, and was over-expressed in human Schwann cell-derived tumors. In contrast, the tyrosine phosphorylation of Gab1 after nerve injury was principally regulated by the neuregulin 1-ErbB2 signaling and was indispensable for remyelination after crush injury, but not for the proliferation and migration of Schwann cells. Our findings indicate that Gab1 and Gab2 in Schwann cells are nonredundant and play a crucial role in peripheral nerve repair. © 2017 Wiley Periodicals, Inc.

  16. Domains and domain loss

    DEFF Research Database (Denmark)

    Haberland, Hartmut

    2005-01-01

    The domain concept, originally suggested by Schmidt-Rohr in the 1930’s (as credited in Fishman’s writings in the 1970s), was an attempt to sort out different areas of language use in multilingual societies, which are relevant for language choice. In Fishman’s version, domains were considered...... as theoretical constructs that can explain language choice which were supposed to be a more powerful explanatory tool than more obvious (and observable) parameters like topic, place (setting) and interlocutor. In the meantime, at least in Scandinavia, the term ‘domain’ has been taken up in the debate among...... politicians and in the media, especially in the discussion whether some languages undergo ‘domain loss’ vis-à-vis powerful international languages like English. An objection that has been raised here is that domains, as originally conceived, are parameters of language choice and not properties of languages...

  17. Schizophrenia-risk variant rs6994992 in the neuregulin-1 gene on brain developmental trajectories in typically developing children.

    Science.gov (United States)

    Douet, V; Chang, L; Pritchett, A; Lee, K; Keating, B; Bartsch, H; Jernigan, T L; Dale, A; Akshoomoff, N; Murray, S; Bloss, C; Kennedy, D N; Amaral, D; Gruen, J; Kaufmann, W E; Casey, B J; Sowell, E; Ernst, T

    2014-05-27

    The neuregulin-1 (NRG1) gene is one of the best-validated risk genes for schizophrenia, and psychotic and bipolar disorders. The rs6994992 variant in the NRG1 promoter (SNP8NRG243177) is associated with altered frontal and temporal brain macrostructures and/or altered white matter density and integrity in schizophrenic adults, as well as healthy adults and neonates. However, the ages when these changes begin and whether neuroimaging phenotypes are associated with cognitive performance are not fully understood. Therefore, we investigated the association of the rs6994992 variant on developmental trajectories of brain macro- and microstructures, and their relationship with cognitive performance. A total of 972 healthy children aged 3-20 years had the genotype available for the NRG1-rs6994992 variant, and were evaluated with magnetic resonance imaging (MRI) and neuropsychological tests. Age-by-NRG1-rs6994992 interactions and genotype effects were assessed using a general additive model regression methodology, covaried for scanner type, socioeconomic status, sex and genetic ancestry factors. Compared with the C-carriers, children with the TT-risk-alleles had subtle microscopic and macroscopic changes in brain development that emerge or reverse during adolescence, a period when many psychiatric disorders are manifested. TT-children at late adolescence showed a lower age-dependent forniceal volume and lower fractional anisotropy; however, both measures were associated with better episodic memory performance. To our knowledge, we provide the first multimodal imaging evidence that genetic variation in NRG1 is associated with age-related changes on brain development during typical childhood and adolescence, and delineated the altered patterns of development in multiple brain regions in children with the T-risk allele(s).

  18. Design and optimization of PLGA microparticles for controlled and local delivery of Neuregulin-1 in traumatic spinal cord injury.

    Science.gov (United States)

    Santhosh, Kallivalappil T; Alizadeh, Arsalan; Karimi-Abdolrezaee, Soheila

    2017-09-10

    Spinal cord injury (SCI) results in significant tissue damage that underlies functional impairments. Pharmacological interventions to confer neuroprotection and promote cell replacement are essential for SCI repair. We previously reported that Neuregulin-1 (Nrg-1) is acutely and permanently downregulated after SCI. Nrg-1 is a critical growth factor for differentiation of neural precursor cells (NPCs) into myelinating oligodendrocytes. We showed that intrathecal delivery of Nrg-1 enhances oligodendrocyte replacement following SCI. While an effective delivery system, intrathecal and systemic administration of growth factors with diverse biological targets may pose adverse off-target effects. Here, we have developed and optimized an injectable biodegradable poly(lactic-co-glycolic acid) (PLGA) microparticles system for sustained and prolonged intraspinal delivery of Nrg-1 in SCI. Recombinant human Nrg-1β1 peptide was encapsulated into PLGA microparticles. Optimal Nrg-1 release rate and duration were achieved by manipulating the porosity and size of PLGA particles. Our in vitro analysis showed a direct correlation between particle size and porosity with Nrg-1 release rate, while Nrg-1 loading efficiency in PLGA microparticles was inversely correlated with particle porosity. In SCI, local intraspinal injection of PLGA-Nrg-1 microparticles maintained significantly higher tissue levels of Nrg-1 for a long-term duration compared to Nrg-1 delivered intrathecally by osmotic pumps. Bioactivity of Nrg-1 in PLGA microparticles was verified by promoting oligodendrocyte differentiation of NPCs in vitro, and preservation of oligodendrocytes and axons in SCI. PLGA-Nrg-1 also attenuated neuroinflammation and glial scarring following SCI. We show, for the first time, the feasibility, efficacy and safety of PLGA microparticle system for local and controlled administration of Nrg-1 in SCI. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Expression and function of Neuregulin 1 and its signaling system ERBB2/3 in the enteric nervous system

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    Martina eBarrenschee

    2015-09-01

    Full Text Available Neuregulin 1 (NRG1 is suggested to promote the survival and maintenance of the enteric nervous system (ENS. As deficiency in its corresponding receptor signaling complex ERBB2/ERBB3 leads to postnatal colonic hypo/aganglionosis we assessed the distributional and expressional pattern of the NRG1-ERBB2/ERBB3 system in the human colon and explored the neurotrophic capacity of NRG1 on cultured enteric neurons.Site-specific mRNA expression of the NRG1-ERBB2/3 system was determined in microdissected samples harvested from enteric musculature and ganglia. Localization of NRG1, ERBB2 and ERBB3 was determined by dual-label-immunohistochemistry using pan-neuronal and pan-glial markers. Morphometric analysis was performed on NRG1-stimulated rat enteric nerve cultures to evaluate neurotrophic effects. mRNA expression of the NRG1-ERBB2/3 system was determined by qPCR. Co-localization of NRG1 with neuronal or synaptic markers was analyzed in enteric nerve cultures stimulated with glial cell line-derived neurotrophic factor (GDNF. The NRG1 system was expressed in both neurons and glial cells of enteric ganglia and in nerve fibers. NRG1 significantly enhanced growth parameters in enteric nerve cell cultures and ErB3 mRNA expression was down-regulated upon NRG1 stimulation. GDNF negatively regulates ErbB2 and ErbB3 mRNA expressionThe NRG1-ERBB2/3 system is physiologically present in the human ENS and NRG1 acts as a neurotrophic factor for the ENS. The down-regulation of ErbB3/ErbB2 in GDNF stimulated nerve cell cultures points to an interaction of both neurotrophic factors. Thus, the data may provide a basis to assess disturbed signaling components of the NRG1 system in enteric neuropathies.

  20. Domain analysis

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2017-01-01

    The domain-analytic approach to knowledge organization (KO) (and to the broader field of library and information science, LIS) is outlined. The article reviews the discussions and proposals on the definition of domains, and provides an example of a domain-analytic study in the field of art studie....... Varieties of domain analysis as well as criticism and controversies are presented and discussed....

  1. An optimized dosing regimen of cimaglermin (neuregulin 1β3, glial growth factor 2) enhances molecular markers of neuroplasticity and functional recovery after permanent ischemic stroke in rats.

    Science.gov (United States)

    Iaci, Jennifer F; Parry, Tom J; Huang, Zhihong; Pavlopoulos, Elias; Finklestein, Seth P; Ren, Jingmei; Caggiano, Anthony

    2016-03-01

    Cimaglermin (neuregulin 1β3, glial growth factor 2) is a neuregulin growth factor family member in clinical development for chronic heart failure. Previously, in a permanent middle cerebral artery occlusion (pMCAO) rat stroke model, systemic cimaglermin treatment initiated up to 7 days after ischemia onset promoted recovery without reduced lesion volume. Presented here to extend the evidence are two studies that use a rat stroke model to evaluate the effects of cimaglermin dose level and dose frequency initiated 24 hr after pMCAO. Forelimb- and hindlimb-placing scores (proprioceptive behavioral tests), body-swing symmetry, and infarct volume were compared between treatment groups (n = 12/group). Possible mechanisms underlying cimaglermin-mediated neurologic recovery were examined through axonal growth and synapse formation histological markers. Cimaglermin was evaluated over a wider dose range (0.02, 0.1, or 1.0 mg/kg) than doses previously shown to be effective but used the same dosing regimen (2 weeks of daily intravenous administration, then 1 week without treatment). The dose-frequency study used the dose-ranging study's most effective dose (1.0 mg/kg) to compare daily, once per week, and twice per week dosing for 3 weeks (then 1 week without treatment). Dose- and frequency-dependent functional improvements were observed with cimaglermin without reduced lesion volume. Cimaglermin treatment significantly increased growth-associated protein 43 expression in both hemispheres (particularly somatosensory and motor cortices) and also increased synaptophysin expression. These data indicate that cimaglermin enhances recovery after stroke. Immunohistochemical changes were consistent with axonal sprouting and synapse formation but not acute neuroprotection. Cimaglermin represents a potential clinical development candidate for ischemic stroke treatment. © 2015 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc.

  2. The Membrane-anchoring Domain of Epidermal Growth Factor Receptor Ligands Dictates Their Ability to Operate in Juxtacrine Mode

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Jianying; Opresko, Lee; Chrisler, William B.; Orr, Galya; Quesenberry, Ryan D.; Lauffenburger, Douglas A.; Wiley, H S.

    2005-06-01

    All ligands of the epidermal growth factor receptor (EGFR) are synthesized as membrane-anchored precursors. Previous work has suggested that some ligands, such as EGF, must be proteolytically released to be active, whereas others, such as heparin binding EGF-like growth factor (HB-EGF) can function while still anchored to the membrane (i.e., juxtacrine signaling). To explore the structural basis for these differences in ligand activity, we engineered a series of membrane-anchored ligands in which the core, receptor-binding domain of EGF was combined with different domains of both EGF and HB-EGF. We found that ligands having the N-terminal extension of EGF could not bind to the EGFR, even when released from the membrane. Ligands lacking an N-terminal extension, but possessing the membrane-anchoring domain of EGF still required proteolytic release for activity, whereas ligands with the membrane anchoring domain of HB-EGF could elicit full biological activity while still membrane anchored. Ligands containing the HB-EGF membrane anchor, but lacking an N-terminal extension, activated EGFR during their transit through the Golgi apparatus . However, cell-mixing experiments and fluorescence resonance energy transfer (FRET) studies showed that juxtacrine signaling typically occurred in trans at the cell surface, at points of cell-cell contact. Our data suggest that the membrane-anchoring domain of ligands selectively controls their ability to participate in juxtacrine signaling and thus, only a subclass of EGFR ligands can act in a juxtacrine mode.

  3. Structural Basis of Native CXCL7 Monomer Binding to CXCR2 Receptor N-Domain and Glycosaminoglycan Heparin

    Directory of Open Access Journals (Sweden)

    Aaron J. Brown

    2017-02-01

    Full Text Available CXCL7, a chemokine highly expressed in platelets, orchestrates neutrophil recruitment during thrombosis and related pathophysiological processes by interacting with CXCR2 receptor and sulfated glycosaminoglycans (GAG. CXCL7 exists as monomers and dimers, and dimerization (~50 μM and CXCR2 binding (~10 nM constants indicate that CXCL7 is a potent agonist as a monomer. Currently, nothing is known regarding the structural basis by which receptor and GAG interactions mediate CXCL7 function. Using solution nuclear magnetic resonance (NMR spectroscopy, we characterized the binding of CXCL7 monomer to the CXCR2 N-terminal domain (CXCR2Nd that constitutes a critical docking site and to GAG heparin. We found that CXCR2Nd binds a hydrophobic groove and that ionic interactions also play a role in mediating binding. Heparin binds a set of contiguous basic residues indicating a prominent role for ionic interactions. Modeling studies reveal that the binding interface is dynamic and that GAG adopts different binding geometries. Most importantly, several residues involved in GAG binding are also involved in receptor interactions, suggesting that GAG-bound monomer cannot activate the receptor. Further, this is the first study that describes the structural basis of receptor and GAG interactions of a native monomer of the neutrophil-activating chemokine family.

  4. ErbB1-4-dependent EGF/neuregulin signals and their cross talk in the central nervous system: pathological implications in schizophrenia and Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Yuriko eIwakura

    2013-02-01

    Full Text Available Ligands for ErbB1-4 receptor tyrosine kinases, such as epidermal growth factor (EGF and neuregulins, regulate brain development and function. Thus, abnormalities in their signaling are implicated in the etiology or pathology of schizophrenia and Parkinson’s disease. Among the ErbB receptors, ErbB1 and ErbB4 are expressed in dopamine and GABA neurons, while ErbB1, 2, and/or 3 are mainly present in oligodendrocytes, astrocytes and their precursors. Thus, deficits in ErbB signaling might contribute to schizophrenia neuropathology stemming from these cell types. By incorporating the latest cancer molecular biology as well as our recent progress, we discuss signal cross talk between the ErbB1-4 subunits and their neurobiological functions in each cell type. The potential contribution of virus-derived cytokines (virokines that mimic EGF and neuregulin-1 in brain diseases are also discussed.

  5. Domain structure and the location of tyrosine-O-sulfate in secreted fibronectin from rat embryo fibroblasts, line 3Y1

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    Liu, M.C.; Suiko, M.; Lipmann, F.

    1986-05-01

    Domain structure of the secreted fibronectin from 3Y1 rat embryo fibroblasts was studied using limited protoelysis technique. Proteolytic fragments were fractionated by a small scale affinity separation procedure employing gelatin-Sepharose, heparin-Agarose and protein A-Sepharose. The three affinity fractions, gelatin-binding, heparin-binding and antibody-precipitated, were then subjected to SDS-PAGE. Domain structure of the secreted fibronectin deduced from the electrophoretic pattern of different binding fragments seemed to comply with the one generally found for other fibronectins which consists of, from N-terminus, Hep-1, Gel, cell-binding, Hep-2 and a C-terminal piece containing interchain disulfide bond(s). Examination of (/sup 35/S)sulfate-labeled fibronectin by the same procedure using trypsin as the protease showed that a 17K and a 40K radioactive band containing tyrosine-O-sulfate (TyS) were present when SDS-PAGE was performed under reducing conditions. Under non-reducing conditions, TyS-containing radioactive bands at 57K and 80K positions were observed indicating the two smaller peptides to be linked through a disulfide bridge. These results suggested that tyrosine-O-sulfate in the 3Y1 secreted fibronectin is located near the C- terminal region, being as close as to within 17K from the C-terminus end.

  6. A motif within the N-terminal domain of TSP-1 specifically promotes the proangiogenic activity of endothelial colony-forming cells.

    Science.gov (United States)

    Dias, Juliana Vieira; Benslimane-Ahmim, Zahia; Egot, Marion; Lokajczyk, Anna; Grelac, Françoise; Galy-Fauroux, Isabelle; Juliano, Luiz; Le-Bonniec, Bernard; Takiya, Cristina Maeda; Fischer, Anne-Marie; Blanc-Brude, Olivier; Morandi, Verônica; Boisson-Vidal, Catherine

    2012-10-15

    Thrombospondin-1 (TSP-1) gives rise to fragments that have both pro- and anti-angiogenic effects in vitro and in vivo. The TSP-HepI peptide (2.3 kDa), located in the N-terminal domain of TSP-1, has proangiogenic effects on endothelial cells. We have previously shown that TSP-1 itself exhibits a dual effect on endothelial colony-forming cells (ECFC) by enhancing their adhesion through its TSP-HepI fragment while reducing their proliferation and differentiation into vascular tubes (tubulogenesis) in vitro. This effect is likely mediated through CD47 binding to the TSP-1 C-terminal domain. Here we investigated the effect of TSP-HepI peptide on the angiogenic properties of ECFC in vitro and in vivo. TSP-HepI peptide potentiated FGF-2-induced neovascularisation by enhancing ECFC chemotaxis and tubulogenesis in a Matrigel plug assay. ECFC exposure to 20 μg/mL of TSP-HepI peptide for 18 h enhanced cell migration (p TSP-HepI peptide with a modified heparin-binding site (S/TSP-HepI) nor when the glycosaminoglycans (GAGs) moieties were removed from the ECFC surface by enzymatic treatment. Ex vivo TSP-HepI priming could potentially serve to enhance the effectiveness of therapeutic neovascularisation with ECFC. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Transgenic Overexpression of the Type I Isoform of Neuregulin 1 Affects Working Memory and Hippocampal Oscillations but not Long-term Potentiation

    Science.gov (United States)

    Deakin, Inga H.; Nissen, Wiebke; Law, Amanda J.; Lane, Tracy; Kanso, Riam; Schwab, Markus H.; Nave, Klaus-Armin; Lamsa, Karri P.; Paulsen, Ole; Bannerman, David M.

    2012-01-01

    Neuregulin 1 (NRG1) is a growth factor involved in neurodevelopment and plasticity. It is a schizophrenia candidate gene, and hippocampal expression of the NRG1 type I isoform is increased in the disorder. We have studied transgenic mice overexpressing NRG1 type I (NRG1tg-type I) and their wild-type littermates and measured hippocampal electrophysiological and behavioral phenotypes. Young NRG1tg-type I mice showed normal memory performance, but in older NRG1tg-type I mice, hippocampus-dependent spatial working memory was selectively impaired. Hippocampal slice preparations from NRG1tg-type I mice exhibited a reduced frequency of carbachol-induced gamma oscillations and an increased tendency to epileptiform activity. Long-term potentiation in NRG1tg-type I mice was normal. The results provide evidence that NRG1 type I impacts on hippocampal function and circuitry. The effects are likely mediated via inhibitory interneurons and may be relevant to the involvement of NRG1 in schizophrenia. However, the findings, in concert with those from other genetic and pharmacological manipulations of NRG1, emphasize the complex and pleiotropic nature of the gene, even with regard to a single isoform. PMID:21878485

  8. Neuregulinas 1-alfa e 1-beta na regeneração de nervos periféricos Neuregulins 1-alpha and 1-beta on the regeneration the peripheral nerves

    Directory of Open Access Journals (Sweden)

    Fabiano Inácio de Souza

    2010-01-01

    Full Text Available OBJETIVO: Avaliar o efeito das neuregulinas 1-alfa e 1-beta na regeneração de nervos ciáticos de camundongos C57BL/6J, adultos, machos, através da técnica de tubulização. MÉTODOS: Utilizaram-se 18 animais, divididos em 3 grupos, implantando-se prótese de polietileno em falhas de 4,0 mm no nervo ciático esquerdo: grupo 1 contendo apenas colágeno purificado (Vitrogen®; grupo 2, colágeno associado a neuregulina 1-alfa; grupo 3 com colágeno e neuregulina 1-beta. O grupo controle foi formado por 6 segmentos de nervos ciáticos direitos. Após 4 semanas, os animais foram sacrificados; extraiu-se segmento do ponto médio do nervo regenerado no interior das próteses, padronizaram-se cortes histológicos e confecção das lâminas para análise histomorfométrica. Confrontaram-se os resultados estatisticamente. RESULTADOS: Os animais tratados com neuregulinas tiveram maior número de axônios mielinizados, com diferença estatisticamente significante quando comparados ao grupo colágeno. Não houve diferença estatística entre os grupos de neuregulinas 1-alfa e 1-beta. CONCLUSÃO: a adição de neuregulinas proporcionou aumento significativo do número de fibras mielinizadas.OBJECTIVE: to evaluate the effect of the neuregulins 1-alpha and 1-beta on the regeneration the sciatic nerves of male adult C57BL/6J mice, using the tubulization technique. METHODS: eighteen animals were used, divided into three groups. A polyethylene prosthesis was implanted in a 4.0 mm defect of the left sciatic nerve, as follows: group 1 containing only purified collagen (Vitrogen®; group 2, collagen with neuregulin 1-alpha; group 3, collagen with neuregulin 1-beta. The control group consisted of six segments of right sciatic nerves. After four weeks, the animals were sacrificed. A segment from the midpoint of the nerve regenerated inside the prostheses was extracted; histological sections were standardized, and slides were made up for histomorphometric analysis

  9. Heparin binding chitosan derivatives for production of pro-angiogenic hydrogels for promoting tissue healing.

    Science.gov (United States)

    Yar, Muhammad; Shahzad, Sohail; Shahzadi, Lubna; Shahzad, Sohail Anjum; Mahmood, Nasir; Chaudhry, Aqif Anwar; Rehman, Ihtesham Ur; MacNeil, Sheila

    2017-05-01

    Our aim was to develop a biocompatible hydrogel that could be soaked in heparin and placed on wound beds to improve the vasculature of poorly vascularized wound beds. In the current study, a methodology was developed for the synthesis of a new chitosan derivative (CSD-1). Hydrogels were synthesized by blending CSD-1 for either 4 or 24h with polyvinyl alcohol (PVA). The physical/chemical interactions and the presence of specific functional groups were confirmed by Fourier transform infrared (FT-IR) spectroscopy and proton nuclear magnetic resonance (1H NMR). The porous nature of the hydrogels was confirmed by scanning electron microscopy (SEM). Thermal gravimetric analysis (TGA) showed that these hydrogels have good thermal stability which was slightly increased as the blending time was increased. Hydrogels produced with 24h of blending supported cell attachment more and could be loaded with heparin to induce new blood vessel formation in a chick chorionic allantoic membrane assay. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Furin proteolytically processes the heparin-binding region of extracellular superoxide dismutase

    DEFF Research Database (Denmark)

    Bowler, Russell P; Nicks, Mike; Olsen, Dorte Aa

    2002-01-01

    Extracellular superoxide dismutase (EC-SOD) is an antioxidant enzyme that attenuates brain and lung injury from oxidative stress. A polybasic region in the carboxyl terminus distinguishes EC-SOD from other superoxide dismutases and determines EC-SOD's tissue half-life and affinity for heparin...

  11. The Role of Heparin-Binding EGF-Like Growth Factor in Breast Cancer

    Science.gov (United States)

    1996-10-01

    MgCl2 and proteinae inhibitors: leupeptin (5 p.g/ml), aprotinin (20 gg/ml) and phenylmethylsulfonyl fluoride (35.8 gtg/ml) and incubated for 15 min at 40C...10 mM Tris, pH 7.6, 5mM EDTA, 50 mM NaCl, 30 mM sodium pyrophosphate, 50 mM sodium fluoride and 1mM sodium orthovanadate and proteinase inhibitors...for 15 min at 4°C. Cells were scraped, centrifuged at 14,000 x g for 15 min at 4°C and supernatant was transferred to a clean tube. Subsequently

  12. Domain crossing

    DEFF Research Database (Denmark)

    Schraefel, M. C.; Rouncefield, Mark; Kellogg, Wendy

    2012-01-01

    In CSCW, how much do we need to know about another domain/culture before we observe, intersect and intervene with designs. What optimally would that other culture need to know about us? Is this a “how long is a piece of string” question, or an inquiry where we can consider a variety of contexts...

  13. Human papillomavirus 16 E2 interacts with neuregulin receptor degradation protein 1 affecting ErbB-3 expression in vitro and in clinical samples of cervical lesions.

    Science.gov (United States)

    Paolini, Francesca; Curzio, Gianfranca; Melucci, Elisa; Terrenato, Irene; Antoniani, Barbara; Carosi, Mariantonia; Mottolese, Marcella; Vici, Patrizia; Mariani, Luciano; Venuti, Aldo

    2016-05-01

    The ErbB tyrosine kinase receptors play a key role in regulating many cellular functions and human papillomaviruses (HPVs) may interact with transductional pathway of different growth factor receptors. Here, these interactions were analysed in W12 cell line carrying HPV 16 genome and in clinical samples. W12 cells, in which HPV16 becomes integrated during passages, were utilised to detect viral and ErbB family expression at early (W12E) and late passages (W12G). Interestingly, a strong reduction of ErbB-3 expression was observed in W12G. Loss of the E2 and E5 viral genes occurs in W12G and this may affect ErbB-3 receptor expression. E2 and E5 rescue experiments demonstrated that only E2 gene was able to restore ErbB-3 expression. E2 is a transcriptional factor but the expression levels of ErbB3 were unaffected and ErbB-3 promoter did not show any consensus sequence for E2, thus E2 may interact in another way with ErbB3. Indeed, HPV 16 E2 can modulate ErbB-3 by interacting with the ubiquitin ligase neuregulin receptor degradation protein 1 (Nrdp-1) that is involved in the regulation of this receptor, via ubiquitination and degradation. E2 co-immunoprecipitated in a complex with Nrdp-1 leading to hypothesise an involvement of this interaction in ErbB-3 regulation. In addition, 90% of the clinical samples with integrated virus and E2 loss showed no or low ErbB-3 positivity, confirming in vitro results. In conclusion, the new discovered interaction of HPV-16 E2 with Nrdp-1 may affect ErbB-3 expression. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Intravenous Glial Growth Factor 2 (GGF2) Isoform of Neuregulin-1β Improves Left Ventricular Function, Gene and Protein Expression in Rats after Myocardial Infarction

    Science.gov (United States)

    Murphy, Abigail; Smith, Holly M.; Galindo, Cristi L.; Pentassuglia, Laura; Peng, Xuyang; Lenneman, Carrie G.; Odiete, Oghenerukevwe; Friedman, David B.; Kronenberg, Marvin W.; Zheng, Siyuen; Zhao, Zhongming; Song, Yanna; Harrell, Frank E.; Srinivas, Maya; Ganguly, Anindita; Iaci, Jennifer; Parry, Tom J.; Caggiano, Anthony O.; Sawyer, Douglas B.

    2013-01-01

    Aims Recombinant Neuregulin (NRG)-1β has multiple beneficial effects on cardiac myocytes in culture, and has potential as a clinical therapy for heart failure (HF). A number of factors may influence the effect of NRG-1β on cardiac function via ErbB receptor coupling and expression. We examined the effect of the NRG-1β isoform, glial growth factor 2 (GGF2), in rats with myocardial infarction (MI) and determined the impact of high-fat diet as well as chronicity of disease on GGF2 induced improvement in left ventricular systolic function. Potential mechanisms for GGF2 effects on the remote myocardium were explored using microarray and proteomic analysis. Methods and Results Rats with MI were randomized to receive vehicle, 0.625 mg/kg, or 3.25 mg/kg GGF2 in the presence and absence of high-fat feeding beginning at day 7 post-MI and continuing for 4 weeks. Residual left ventricular (LV) function was improved in both of the GGF2 treatment groups compared with the vehicle treated MI group at 4 weeks of treatment as assessed by echocardiography. High-fat diet did not prevent the effects of high dose GGF2. In experiments where treatment was delayed until 8 weeks after MI, high but not low dose GGF2 treatment was associated with improved systolic function. mRNA and protein expression analysis of remote left ventricular tissue revealed a number of changes in myocardial gene and protein expression altered by MI that were normalized by GGF2 treatment, many of which are involved in energy production. Conclusions This study demonstrates that in rats with MI induced systolic dysfunction, GGF2 treatment improves cardiac function. There are differences in sensitivity of the myocardium to GGF2 effects when administered early vs. late post-MI that may be important to consider in the development of GGF2 in humans. PMID:23437060

  15. Sensorimotor Gating Depends on Polymorphisms of the Serotonin-2A Receptor and Catechol-O-Methyltransferase, but Not on Neuregulin-1 Arg38Gln Genotype: A Replication Study

    Science.gov (United States)

    Quednow, Boris B.; Schmechtig, Anne; Ettinger, Ulrich; Petrovsky, Nadine; Collier, David A.; Vollenweider, Franz X.; Wagner, Michael; Kumari, Veena

    2009-01-01

    Background Prepulse inhibition (PPI) of the acoustic startle response (ASR) is an operational measure of sensorimotor gating and a promising endophenotype of schizophrenia. We have recently shown that the linked serotonin-2A receptor (5-HT2AR) A-1438 G and T102C polymorphisms modulate PPI in schizophrenia patients. Moreover, it was shown that genetic variation in the catechol-O-methyltransferase (COMT) and the neuregulin-1 (NRG-1) proteins influences PPI in schizophrenia patients and healthy volunteers. Therefore, we aimed to replicate these results and investigated the impact of the related polymorphisms on PPI in healthy human volunteers. Methods We analyzed the 5-HT2AR A-1438 G/T102C (rs6311/rs6313), the COMT Val158Met (rs4680), and the NRG-1 Arg38Gln (rs3924999) polymorphisms, assessing startle reactivity, habituation, and PPI of ASR in 107 healthy Caucasian volunteers. Results Subjects homozygous for the 5-HT2AR T102C-T/A-1438 G-A allele showed increased PPI levels. In particular, male subjects with the COMT Met158Met-genotype also showed elevated PPI. The NRG-1 Arg38Gln genotype did not have a significant impact on PPI. Startle reactivity was not affected by any of the investigated polymorphisms. Conclusions We confirmed in an independent sample of healthy volunteers that PPI is influenced by genetic variation in the 5-HT2AR gene. The influence of the COMT Val158Met genotype on PPI appears to be sex-specific. These results underscore the significance of the serotonin and dopamine systems in the modulation of sensorimotor gating. PMID:19545856

  16. Neuregulin-1 regulates cell adhesion via an ErbB2/phosphoinositide-3 kinase/Akt-dependent pathway: potential implications for schizophrenia and cancer.

    Directory of Open Access Journals (Sweden)

    Christopher G Kanakry

    2007-12-01

    Full Text Available Neuregulin-1 (NRG1 is a putative schizophrenia susceptibility gene involved extensively in central nervous system development as well as cancer invasion and metastasis. Using a B lymphoblast cell model, we previously demonstrated impairment in NRG1alpha-mediated migration in cells derived from patients with schizophrenia as well as effects of risk alleles in NRG1 and catechol-O-methyltransferase (COMT, a second gene implicated both in schizophrenia susceptibility and in cancer.Here, we examine cell adhesion, an essential component process of cell motility, using an integrin-mediated cell adhesion assay based on an interaction between ICAM-1 and the CD11a/CD18 integrin heterodimer expressed on lymphoblasts. In our assay, NRG1alpha induces lymphoblasts to assume varying levels of adhesion characterized by time-dependent fluctuations in the firmness of attachment. The maximum range of variation in adhesion over sixty minutes correlates strongly with NRG1alpha-induced migration (r(2 = 0.61. NRG1alpha-induced adhesion variation is blocked by erbB2, PI3K, and Akt inhibitors, but not by PLC, ROCK, MLCK, or MEK inhibitors, implicating the erbB2/PI3K/Akt1 signaling pathway in NRG1-stimulated, integrin-mediated cell adhesion. In cell lines from 20 patients with schizophrenia and 20 normal controls, cells from patients show a significant deficiency in the range of NRG1alpha-induced adhesion (p = 0.0002. In contrast, the response of patient-derived cells to phorbol myristate acetate is unimpaired. The COMT Val108/158Met genotype demonstrates a strong trend towards predicting the range of the NRG1alpha-induced adhesion response with risk homozygotes having decreased variation in cell adhesion even in normal subjects (p = 0.063.Our findings suggest that a mechanism of the NRG1 genetic association with schizophrenia may involve the molecular biology of cell adhesion.

  17. Tissue engineering intrafusal fibers: dose- and time-dependent differentiation of nuclear bag fibers in a defined in vitro system using neuregulin 1-beta-1.

    Science.gov (United States)

    Rumsey, John W; Das, Mainak; Kang, Jung-Fong; Wagner, Robert; Molnar, Peter; Hickman, James J

    2008-03-01

    While much is known about muscle spindle structure, innervation and function, relatively few factors have been identified that regulate intrafusal fiber differentiation and spindle development. Identification of these factors will be a crucial step in tissue engineering functional muscle systems. In this study, we investigated the role of the growth factor, neuregulin 1-beta-1 (Nrg 1-beta-1) EGF, for its ability to influence myotube fate specification in a defined culture system utilizing the non-biological substrate N-1[3-(trimethoxysilyl)propyl]-diethylenetriamine (DETA). Based on morphological and immunocytochemical criteria, Nrg 1-beta-1 treatment of developing myotubes increases the ratio of nuclear bag fibers to total myotubes from 0.019 to 0.100, approximately a five-fold increase. The myotube cultures were evaluated for expression of the intrafusal fiber-specific alpha cardiac-like myosin heavy chain and for the expression of the non-specific slow myosin heavy chain. Additionally, the expression of ErbB2 receptors on all myotubes was observed, while phosphorylated ErbB2 receptors were only observed in Nrg 1-beta-1-treated intrafusal fibers. After Nrg 1-beta-1 treatment, we were able to observe the expression of the intrafusal fiber-specific transcription factor Egr3 only in fibers exhibiting the nuclear bag phenotype. Finally, nuclear bag fibers were characterized electrophysiologically for the first time in vitro. This data shows conclusively, in a serum-free system, that Nrg 1-beta-1 is necessary to drive specification of forming myotubes to the nuclear bag phenotype.

  18. Rapid transient isoform-specific neuregulin1 transcription in motor neurons is regulated by neurotrophic factors and axon-target interactions

    Science.gov (United States)

    Wang, Jiajing; Hmadcha, Abdelkrim; Zakarian, Vaagn; Song, Fei; Loeb, Jeffrey A.

    2015-01-01

    The neuregulins (NRGs) are a family of alternatively spliced factors that play important roles in nervous system development and disease. In motor neurons, NRG1 expression is regulated by activity and neurotrophic factors, however, little is known about what controls isoform-specific transcription. Here we show that NRG1 expression in the chick embryo increases in motor neurons that have extended their axons and that limb bud ablation before motor axon outgrowth prevents this induction, suggesting a trophic role from the developing limb. Consistently, NRG1 induction after limb bud ablation can be rescued by adding back the neurotrophic factors BDNF and GDNF. Mechanistically, BDNF induces a rapid and transient increase in type I and type III NRG1 mRNAs that peak at 4 h in rat embryonic ventral spinal cord cultures. Blocking MAPK or PI3K signaling or blocking transcription with Actinomycin D blocks BDNF induced NRG1 gene induction. BDNF had no effect on mRNA degradation, suggesting that transcriptional activation rather than message stability is important. Furthermore, BDNF activates a reporter construct that includes 700bp upstream of the type I NRG1 start site. Protein synthesis is also required for type I NRG1 mRNA transcription as cycloheximide produced a super-induction of type I, but not type III NRG1 mRNA, possibly through a mechanism involving sustained activation of MAPK and PI3K. These results reveal the existence of highly responsive, transient transcriptional regulatory mechanisms that differentially modulate NRG1 isoform expression as a function of extracellular and intracellular signaling cascades and mediated by neurotrophic factors and axon-target interactions. PMID:25913151

  19. Intravenous glial growth factor 2 (GGF2 isoform of neuregulin-1β improves left ventricular function, gene and protein expression in rats after myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Michael F Hill

    Full Text Available Recombinant Neuregulin (NRG-1β has multiple beneficial effects on cardiac myocytes in culture, and has potential as a clinical therapy for heart failure (HF. A number of factors may influence the effect of NRG-1β on cardiac function via ErbB receptor coupling and expression. We examined the effect of the NRG-1β isoform, glial growth factor 2 (GGF2, in rats with myocardial infarction (MI and determined the impact of high-fat diet as well as chronicity of disease on GGF2 induced improvement in left ventricular systolic function. Potential mechanisms for GGF2 effects on the remote myocardium were explored using microarray and proteomic analysis.Rats with MI were randomized to receive vehicle, 0.625 mg/kg, or 3.25 mg/kg GGF2 in the presence and absence of high-fat feeding beginning at day 7 post-MI and continuing for 4 weeks. Residual left ventricular (LV function was improved in both of the GGF2 treatment groups compared with the vehicle treated MI group at 4 weeks of treatment as assessed by echocardiography. High-fat diet did not prevent the effects of high dose GGF2. In experiments where treatment was delayed until 8 weeks after MI, high but not low dose GGF2 treatment was associated with improved systolic function. mRNA and protein expression analysis of remote left ventricular tissue revealed a number of changes in myocardial gene and protein expression altered by MI that were normalized by GGF2 treatment, many of which are involved in energy production.This study demonstrates that in rats with MI induced systolic dysfunction, GGF2 treatment improves cardiac function. There are differences in sensitivity of the myocardium to GGF2 effects when administered early vs. late post-MI that may be important to consider in the development of GGF2 in humans.

  20. Trusted Domain

    DEFF Research Database (Denmark)

    Hjorth, Theis Solberg; Torbensen, Rune

    2012-01-01

    In the digital age of home automation and with the proliferation of mobile Internet access, the intelligent home and its devices should be accessible at any time from anywhere. There are many challenges such as security, privacy, ease of configuration, incompatible legacy devices, a wealth...... of wireless standards, limited resources of embedded systems, etc. Taking these challenges into account, we present a Trusted Domain home automation platform, which dynamically and securely connects heterogeneous networks of Short-Range Wireless devices via simple non-expert user. interactions, and allows...... remote access via IP-based devices such as smartphones. The Trusted Domain platform fits existing legacy technologies by managing their interoperability and access controls, and it seeks to avoid the security issues of relying on third-party servers outside the home. It is a distributed system...

  1. Nicotine-induced neuroplasticity counteracts the effect of schizophrenia-linked neuregulin 1 signaling on NMDAR function in the rat hippocampus.

    Science.gov (United States)

    Yamazaki, Yoshihiko; Sumikawa, Katumi

    2017-02-01

    A high rate of heavy tobacco smoking among people with schizophrenia has been suggested to reflect self-medication and amelioration of cognitive dysfunction, a core feature of schizophrenia. NMDAR hypofunction is hypothesized to be a mechanism of cognitive dysfunction, and excessive schizophrenia-linked neuregulin 1 (NRG1) signaling through its receptor ErbB4 can suppress NMDAR function by preventing Src-mediated enhancement of NMDAR responses. Here we investigated whether chronic nicotine exposure in rats by subcutaneous injection of nicotine (0.5-1 mg/kg, twice daily for 10-15 days) counteracts the suppressive effect of NRG1β on NMDAR-mediated responses recorded from CA1 pyramidal cells in acute hippocampal slices. We found that NRG1β, which prevents the enhancement of NMDAR responses by the Src-family-kinase-activating peptide pYEEI in naive rats, failed to block the effect of pYEEI in nicotine-exposed rats. In naive rats, NRG1β acts only on GluN2B-NMDARs by blocking their Src-mediated upregulation. Chronic nicotine exposure causes enhanced GluN2B-NMDAR responses via Src upregulation and recruits Fyn for the enhancement of GluN2A-NMDAR responses. NRG1β has no effect on both enhanced basal GluN2B-NMDAR responses and Fyn-mediated enhancement of GluN2A-NMDAR responses. Src-mediated enhancement of GluN2B-NMDAR responses and Fyn-mediated enhancement of GluN2A-NMDAR responses initiate long-term potentiation (LTP) of AMPAR synaptic responses in naive and nicotine-exposed CA1 pyramidal cells, respectively. These results suggest that NRG1β suppresses LTP by blocking Src-mediated enhancement of GluN2B-NMDAR responses, but has no effect on LTP in nicotine-exposed rats. These effects of chronic nicotine exposure may counteract the negative effect of increased NRG1-ErbB4 signaling on the cellular mechanisms of learning and memory in individuals with schizophrenia, and therefore may motivate heavy smoking. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Type 1 diabetes mellitus abrogates compensatory augmentation of myocardial neuregulin-1β/ErbB in response to myocardial infarction resulting in worsening heart failure.

    Science.gov (United States)

    Odiete, Oghenerukevwe; Konik, Ewa A; Sawyer, Douglas B; Hill, Michael F

    2013-03-27

    Diabetes mellitus (DM) patients surviving myocardial infarction (MI) exhibit a substantially higher incidence of subsequent heart failure (HF). Neuregulin (NRG)-1 and erythroblastic leukemia viral oncogene homolog (ErbB) receptors have been shown to play a critical role in maintenance of cardiac function. However, whether myocardial NRG-1/ErbB is altered during post-MI HF associated with DM remains unknown. The aim of this study was to determine the impact of type 1 DM on the myocardial NRG-1/ErbB system following MI in relation to residual left ventricular (LV) function. Type 1 DM was induced in rats via administration of streptozotocin (65 mg/kg, i.p.). Control rats were injected with citrate buffer (vehicle) only. Two weeks after induction of type 1 DM, MI was produced in DM and non-DM rats by ligation of the left coronary artery. Sham MI rats underwent the same surgical procedure with the exception that the left coronary artery was not ligated. At 4 weeks after surgery, residual in vivo LV function was assessed via echocardiography. Myocardial protein expression of NRG-1β, ErbB2 and ErbB4 receptors, and MDM2 (a downstream signaling pathway induced by NRG-1 that has been implicated in cell survival) was assessed in the remaining, viable LV myocardium by Western blotting. Changes in ErbB receptor localization in the surviving LV myocardium of diabetic and non-diabetic post-MI rats was determined using immunohistochemistry techniques. At 4 weeks post-MI, echocardiography revealed that LV fractional shortening (FS) and LV ejection fraction (EF) were significantly lower in the DM + MI group compared to the MI group (LVFS: 17.9 ± 0.7 vs. 25.2 ± 2.2; LVEF: 35.5 ± 1.4 vs. 47.5 ± 3.5, respectively; P < 0.05), indicating an increased functional severity of HF among the DM + MI rats. Up-regulation of NRG-1β and ErbB2 protein expression in the MI group was abrogated in the DM + MI group concurrent with degradation of MDM2, a downstream negative regulator of p53. Erb

  3. Interaction of the amyloid precursor protein-like protein 1 (APLP1) E2 domain with heparan sulfate involves two distinct binding modes

    Energy Technology Data Exchange (ETDEWEB)

    Dahms, Sven O., E-mail: sdahms@fli-leibniz.de [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany); Mayer, Magnus C. [Freie Universität Berlin, Thielallee 63, 14195 Berlin (Germany); Miltenyi Biotec GmbH, Robert-Koch-Strasse 1, 17166 Teterow (Germany); Roeser, Dirk [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany); Multhaup, Gerd [McGill University Montreal, Montreal, Quebec H3G 1Y6 (Canada); Than, Manuel E., E-mail: sdahms@fli-leibniz.de [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany)

    2015-03-01

    Two X-ray structures of APLP1 E2 with and without a heparin dodecasaccharide are presented, revealing two distinct binding modes of the protein to heparan sulfate. The data provide a mechanistic explanation of how APP-like proteins bind to heparan sulfates and how they specifically recognize nonreducing structures of heparan sulfates. Beyond the pathology of Alzheimer’s disease, the members of the amyloid precursor protein (APP) family are essential for neuronal development and cell homeostasis in mammals. APP and its paralogues APP-like protein 1 (APLP1) and APP-like protein 2 (APLP2) contain the highly conserved heparan sulfate (HS) binding domain E2, which effects various (patho)physiological functions. Here, two crystal structures of the E2 domain of APLP1 are presented in the apo form and in complex with a heparin dodecasaccharide at 2.5 Å resolution. The apo structure of APLP1 E2 revealed an unfolded and hence flexible N-terminal helix αA. The (APLP1 E2){sub 2}–(heparin){sub 2} complex structure revealed two distinct binding modes, with APLP1 E2 explicitly recognizing the heparin terminus but also interacting with a continuous heparin chain. The latter only requires a certain register of the sugar moieties that fits to a positively charged surface patch and contributes to the general heparin-binding capability of APP-family proteins. Terminal binding of APLP1 E2 to heparin specifically involves a structure of the nonreducing end that is very similar to heparanase-processed HS chains. These data reveal a conserved mechanism for the binding of APP-family proteins to HS and imply a specific regulatory role of HS modifications in the biology of APP and APP-like proteins.

  4. .Gov Domains API

    Data.gov (United States)

    General Services Administration — This dataset offers the list of all .gov domains, including state, local, and tribal .gov domains. It does not include .mil domains, or other federal domains outside...

  5. Domains in multiband superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Y., E-mail: y.tanaka@aist.go.jp [National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba-shi, Ibaraki-ken 305-8568 (Japan); Yanagisawa, T. [National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba-shi, Ibaraki-ken 305-8568 (Japan); Crisan, A. [University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)] [National Institute of Materials Physics, P.O. Box MG-7, Bucharest 077125 (Romania); Shirage, P.M.; Iyo, A. [National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba-shi, Ibaraki-ken 305-8568 (Japan); Tokiwa, K. [Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba-ken 278-8510 (Japan); Nishio, T. [Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601 (Japan); Sundaresan, A. [Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064 (India); Terada, N. [Kagoshima University, Korimoto 1-21-24, Kagoshima-shi, Kagoshima-ken 890-8580 (Japan)

    2011-11-15

    Positive interband Josephson interactions disperse order parameters. It creates configuration domain in multiband superconductors. This domain poses a problem for the stability of superconductivity. However it also offer new potential for novel electronics. Multiband superconductors can have several types of domains that are inhibited in conventional single-band superconductors. These domains are phase domains and chiral domains and their domain wall are an interband phase difference soliton. In a superconductor with an odd number of electronic bands (five or more) and with positive interband Josephson interactions, we find other types of domains with different interband phase differences. We call these domains configuration domains because pseudo-order parameters for each band are dispersed in the complex plain and several configurations, which have several local minima. Fractional vortices serve as hubs for phase difference solitons (configuration domain walls). The divergence of the number of configurations with local minima would pose a serious problem for the stability of superconductivity.

  6. Domains of laminin

    DEFF Research Database (Denmark)

    Engvall, E; Wewer, U M

    1996-01-01

    Extracellular matrix molecules are often very large and made up of several independent domains, frequently with autonomous activities. Laminin is no exception. A number of globular and rod-like domains can be identified in laminin and its isoforms by sequence analysis as well as by electron...... microscopy. Here we present the structure-function relations in laminins by examination of their individual domains. This approach to viewing laminin is based on recent results from several laboratories. First, some mutations in laminin genes that cause disease have affected single laminin domains, and some...... laminin isoforms lack particular domains. These mutants and isoforms are informative with regard to the activities of the mutated and missing domains. These mutants and isoforms are informative with regard to the activities of the mutated and missing domains. Second, laminin-like domains have now been...

  7. Domain Specific Problem Solving.

    Science.gov (United States)

    Eade, Frank

    1989-01-01

    Outlines a possible framework for allowing teachers to explore how children learn mathematics. A mathematical modelling process and three domains, including content, process and pragmatic domain, are described. Twelve strategies for encouraging children to translate between the domains are suggested. (YP)

  8. PDP: protein domain parser.

    Science.gov (United States)

    Alexandrov, Nickolai; Shindyalov, Ilya

    2003-02-12

    We have developed a program for automatic identification of domains in protein three-dimensional structures. Performance of the program was assessed by three different benchmarks: (i) by comparison with the expert-curated SCOP database of structural domains; (ii) by comparison with a collection of manual domain assignments; and (iii) by comparison with a set of 55 proteins, frequently used as a benchmark for automatic domain assignment. In all these benchmarks PDP identified domains correctly in more than 80% of proteins. http://123d.ncifcrf.gov/.

  9. Treatment with aromatase inhibitors stimulates the expression of epidermal growth factor receptor-1 and neuregulin 1 in ER positive/HER-2/neu non-amplified primary breast cancers.

    Science.gov (United States)

    Flågeng, Marianne Hauglid; Larionov, Alexey; Geisler, Jürgen; Knappskog, Stian; Prestvik, Wenche S; Bjørkøy, Geir; Lilleng, Peer Kåre; Dixon, J Michael; Miller, William R; Lønning, Per Eystein; Mellgren, Gunnar

    2017-01-01

    While estrogens have been shown to modulate EGFR/HER-1 and HER-2/neu expression in experimental systems, the effects of estrogen deprivation on expression levels of the HER-receptors and the neuregulin (NRG)1 ligand in breast cancers remain unknown. Here, we measured EGFR/HER-1-4 and NRG1 mRNA in ER positive tumors from 85 postmenopausal breast cancer patients before and after two weeks (n=64) and three months (n=85) of primary treatment with an aromatase inhibitor (AI). In tumors lacking HER-2/neu amplification, quantitative real-time PCR analyses revealed EGFR/HER-1 and NRG1 to vary significantly between the three time points (before therapy, after 2 weeks and after 3 months on treatment; P≤0.001 for both). Pair-wise comparison revealed a significant increase in EGFR/HER-1 already during the first two weeks of treatment (P=0.049) with a further increase for both EGFR/HER-1 and NRG1 after 3 months on treatment (P≤0.001 and P=0.001 for both comparing values at 3 months to values at baseline and 2 weeks respectively). No difference between tumors responding versus non-responders was recorded. Further, no significant change in any parameter was observed among HER-2/neu amplified tumors. Analyzing components of the HER-2/neu PI3K/Akt downstream pathway, the PIK3CA H1047R mutation was associated with treatment response (P=0.035); however no association between either AKT phosphorylation status or PIK3CA gene mutations and EGFR/HER-1 or NRG1 expression levels were observed. Our results indicate primary AI treatment to modulate expression of HER-family members and the growth factor NRG1 in HER-2/neu non-amplified breast cancers in vivo. Potential implications to long term sensitivity warrants further investigations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Domains and Naive Theories.

    Science.gov (United States)

    Gelman, Susan A; Noles, Nicholaus S

    2011-09-01

    Human cognition entails domain-specific cognitive processes that influence memory, attention, categorization, problem-solving, reasoning, and knowledge organization. This review examines domain-specific causal theories, which are of particular interest for permitting an examination of how knowledge structures change over time. We first describe the properties of commonsense theories, and how commonsense theories differ from scientific theories, illustrating with children's classification of biological and non-biological kinds. We next consider the implications of domain-specificity for broader issues regarding cognitive development and conceptual change. We then examine the extent to which domain-specific theories interact, and how people reconcile competing causal frameworks. Future directions for research include examining how different content domains interact, the nature of theory change, the role of context (including culture, language, and social interaction) in inducing different frameworks, and the neural bases for domain-specific reasoning.

  11. Supersymmetric domain walls

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; Kleinschmidt, Axel; Riccioni, Fabio

    2012-01-01

    We classify the half-supersymmetric "domain walls," i.e., branes of codimension one, in toroidally compactified IIA/IIB string theory and show to which gauged supergravity theory each of these domain walls belong. We use as input the requirement of supersymmetric Wess-Zumino terms, the properties of

  12. GlycoDomainViewer

    DEFF Research Database (Denmark)

    Joshi, Hiren J; Jørgensen, Anja; Schjoldager, Katrine T

    2018-01-01

    The GlycoDomainViewer is a bioinformatic tool to aid in the mining of glycoproteomic data sets from different sources and facilitate incorporation of glycosylation into studies of protein structure and function. We present a version 2.0 of GlycoDomainViewer incorporating a number of advanced feat...

  13. Cholesterol Domains Enhance Transfection

    Science.gov (United States)

    Betker, Jamie L.; Kullberg, Max; Gomez, Joe; Anchordoquy, Thomas J.

    2014-01-01

    The formation of cholesterol domains in lipoplexes has been associated with enhanced serum stability and transfection rates both in cell culture and in vivo. This study utilizes the ability of saturated phosphatidylcholines to promote the formation of cholesterol domains at much lower cholesterol contents than have been utilized in previous work. The results show that lipoplexes with identical cholesterol and cationic lipid contents exhibit significantly improved transfection efficiencies when a domain is present, consistent with previous work. In addition, studies assessing transfection rates in the absence of serum demonstrate that the ability of domains to enhance transfection is not dependent on interactions with serum proteins. Consistent with this hypothesis, characterization of the adsorbed proteins composing the corona of these lipoplex formulations did not reveal a correlation between transfection and the adsorption of a specific protein. Finally, we show that the interaction with serum proteins can promote domain formation in some formulations, and thereby result in enhanced transfection only after serum exposure. PMID:23557286

  14. Conserved Domain Database (CDD)

    Data.gov (United States)

    U.S. Department of Health & Human Services — CDD is a protein annotation resource that consists of a collection of well-annotated multiple sequence alignment models for ancient domains and full-length proteins.

  15. Large stable magnetic domains

    Science.gov (United States)

    Pulliam, G. R.; Ross, W. E.; MacNeal, B.; Bailey, R. F.

    1982-03-01

    Large, thin-film single domain areas have been observed, in the absence of a bias field, in garnets with magnetization perpendicular to the film plane.1,2 The domain stability in the work by Krumme1 was attributed to a combination of low saturation magnetization and a low Curie temperature. Uchishiba2 relates the stability in his double layer system to appropriate anisotropy fields in one layer compared to the magnetization in the other layer. A more complete model for large domain stability in a bias field free environment is given in this work. Three distinct stability regimes are predicted by the model and all have been observed experimentally. Areas 3.5-cm in diameter have been made into stable single domains. This was achieved in a material showing a zero bias strip width of 4.5 μm. The single domain diameter was, therefore, 7500 times the equilibrium energy domain width. The technique developed and the model have led to a new means for observing magnetic defects. More importantly, it also offers a means for measuring the strength of the defects. Possible applications of the model are also discussed.

  16. Nuclear translocation of the cytoplasmic domain of HB-EGF induces gastric cancer invasion

    Science.gov (United States)

    2012-01-01

    Background Membrane-anchored heparin-binding epidermal growth factor-like growth factor (proHB-EGF) yields soluble HB-EGF, which is an epidermal growth factor receptor (EGFR) ligand, and a carboxy-terminal fragment of HB-EGF (HB-EGF-CTF) after ectodomain shedding. We previously reported that HB-EGF-CTF and unshed proHB-EGF which has the cytoplasmic domain of proHB-EGF (HB-EGF-C), translocate from the plasma membrane to the nucleus and regulate cell cycle after shedding stimuli. However, the significance of nuclear exported HB-EGF-C in human gastric cancer is unclear. Methods We investigated the relationship between intracellular localization of HB-EGF-C and clinical outcome in 96 gastric cancer patients treated with gastrectomy. Moreover, we established stable gastric cancer cell lines overexpressing wild-type HB-EGF (wt-HB-EGF) and mutated HB-EGF (HB-EGF-mC), which prevented HB-EGF-C nuclear translocation after shedding. Cell motility between these 2 gastric cancer cell lines was investigated using a transwell invasion assay and a wound healing assay. Results Of the 96 gastric cancer cases, HB-EGF-C immunoreactivity was detected in both the nucleus and cytoplasm in 19 cases (19.8 %) and in the cytoplasm only in 25 cases (26.0 %). The nuclear immunoreactivity of HB-EGF-C was significantly increased in stage pT3/4 tumors compared with pT1/2 tumors (T1/2 vs. T3/4: 11.1 % vs. 36.4 %, P HB-EGF- and HB-EGF-mC-expressing cells significantly increased compared with control cells, but the growth of HB-EGF-mC-expressing cells was significantly decreased compared with wt-HB-EGF-expressing cells. Gastric cancer cell invasion obviously increased in wt-HB-EGF-expressing cells, but invasion in HB-EGF-mC-expressing cells showed a slight increase compared with control cells. Moreover, wt-HB-EGF overexpression increased the effectiveness of wound healing, but had no significant effect in HB-EGF-mC-expressing cells. Conclusions Both the function of HB-EGF as an EGFR ligand

  17. Domains in Ferroelectric Nanostructures

    Science.gov (United States)

    Gregg, Marty

    2010-03-01

    Ferroelectric materials have great potential in influencing the future of small scale electronics. At a basic level, this is because ferroelectric surfaces are charged, and so interact strongly with charge-carrying metals and semiconductors - the building blocks for all electronic systems. Since the electrical polarity of the ferroelectric can be reversed, surfaces can both attract and repel charges in nearby materials, and can thereby exert complete control over both charge distribution and movement. It should be no surprise, therefore, that microelectronics industries have already looked very seriously at harnessing ferroelectric materials in a variety of applications, from solid state memory chips (FeRAMs) to field effect transistors (FeFETs). In all such applications, switching the direction of the polarity of the ferroelectric is a key aspect of functional behavior. The mechanism for switching involves the field-induced nucleation and growth of domains. Domain coarsening, through domain wall propagation, eventually causes the entire ferroelectric to switch its polar direction. It is thus the existence and behavior of domains that determine the switching response, and ultimately the performance of the ferroelectric device. A major issue, associated with the integration of ferroelectrics into microelectronic devices, has been that the fundamental properties associated with ferroelectrics, when in bulk form, appear to change quite dramatically and unpredictably when at the nanoscale: new modes of behaviour, and different functional characteristics from those seen in bulk appear. For domains, in particular, the proximity of surfaces and boundaries have a dramatic effect: surface tension and depolarizing fields both serve to increase the equilibrium density of domains, such that minor changes in scale or morphology can have major ramifications for domain redistribution. Given the importance of domains in dictating the overall switching characteristics of a device

  18. Domain Theory for Concurrency

    DEFF Research Database (Denmark)

    Nygaard, Mikkel

    Concurrent computation can be given an abstract mathematical treatment very similar to that provided for sequential computation by domain theory and denotational semantics of Scott and Strachey. A simple domain theory for concurrency is presented. Based on a categorical model of linear logic and ...... towards more expressive languages than HOPLA and Affine HOPLA—in particular concerning extensions to cover independence models. The thesis concludes with a discussion of related work towards a fully fledged domain theory for concurrency.......Concurrent computation can be given an abstract mathematical treatment very similar to that provided for sequential computation by domain theory and denotational semantics of Scott and Strachey. A simple domain theory for concurrency is presented. Based on a categorical model of linear logic...... equivalence. One language, called HOPLA for Higher-Order Process LAnguage, derives from an exponential of linear logic. It can be viewed as an extension of the simply-typed lambda calculus with CCS-like nondeterministic sum and prefix operations, in which types express the form of computation path of which...

  19. Reasoning in incomplete domains

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, S.

    1979-01-01

    Most real-world domains differ from the micro-worlds traditionally used in A.I. in that they have an incomplete factual data base which changes over time. Understanding in these domains can be thought of as the gneration of plausible infoerences which are able to use the facts available, and respond to changes in them. A traditional rule interpreter such as Planner can be extended to construct plausible inferences in these domains by allowing assumptions to be made in applying rules, resultsing in simplifications of rules which can be used in an incomplete data base; monitoring the antecedents and consequents of a rule so that inferences can be maintained over a changing data base.

  20. Domain-Specific Multimodeling

    DEFF Research Database (Denmark)

    Hessellund, Anders

    the overall level of abstraction. It does, however, also introduce a new problem of coordinating multiple different languages in a single system. We call this problem the coordination problem. In this thesis, we present the coordination method for domain-specific multimodeling that explicitly targets...

  1. Charged Domain Walls

    OpenAIRE

    Campanelli, L.; Cea, P.; Fogli, G. L.; Tedesco, L.

    2003-01-01

    In this paper we investigate Charged Domain Walls (CDW's), topological defects that acquire surface charge density $Q$ induced by fermion states localized on the walls. The presence of an electric and magnetic field on the walls is also discussed. We find a relation in which the value of the surface charge density $Q$ is connected with the existence of such topological defects.

  2. Domain: Labour market

    NARCIS (Netherlands)

    Oude Mulders, J.; Wadensjö, E.; Hasselhorn, H.M.; Apt, W.

    This domain chapter is dedicated to summarize research on the effects of labour market contextual factors on labour market participation of older workers (aged 50+) and identify research gaps. While employment participation and the timing of (early) retirement is often modelled as an individual

  3. The framing of scientific domains

    DEFF Research Database (Denmark)

    Dam Christensen, Hans

    2014-01-01

    Purpose: By using the UNISIST models this article argues for the necessity of domain analysis in order to qualify scientific information seeking. The models better understanding of communication processes in a scientific domain and embraces the point that domains are always both unstable over time...... domains, and UNISIST helps understanding this navigation. Design/methodology/approach The UNISIST models are tentatively applied to the domain of art history at three stages, respectively two modern, partially overlapping domains, as well as an outline of an art historical domain anno c1820...... as according to the agents that are charting them. As such, power in a Foucauldian sense is unavoidable in outlining a domain. Originality/value 1. The UNISIST models are applied to the domain of art history; and 2. the article discusses the instability of a scientific domain as well as, at the same time...

  4. Anti-HER3 Domain 1 and 3 Antibodies Reduce Tumor Growth by Hindering HER2/HER3 Dimerization and AKT-Induced MDM2, XIAP, and FoxO1 Phosphorylation

    Directory of Open Access Journals (Sweden)

    Yassamine Lazrek

    2013-03-01

    Full Text Available Blockade of the human epidermal growth factor receptor 3 (HER3 and of the downstream phosphatidylinositide 3-kinase (PI3K/AKT pathway is a prerequisite for overcoming drug resistance and to develop novel treatments for cancers that are not eligible for the currently approved targeted therapies. To this end, we generated specific antibodies (Abs against domain 1 (D1 and domain 3 (D3 of HER3 that recognize epitopes that do not overlap with the neuregulin-binding site. The fully human H4B-121 Ab and the mouse monoclonal Abs 16D3-C1 and 9F7-F11 inhibited tumor growth in nude mice xenografted with epidermoid, pancreatic, or triple-negative breast cancer cells. The combination of one anti-HER3 Ab and trastuzumab improved tumor growth inhibition in mice xenografted with HER2low cancer cell lines, for which trastuzumab alone shows no or moderate efficiency. Ab-induced disruption of tumor growth was associated with G1 cell cycle arrest, proliferation inhibition, and apoptosis of cancer cells. Anti-HER3 Abs blocked HER2/HER3 heterodimerization and HER3 phosphorylation at the cell membrane, leading to inhibition of phosphorylation of the downstream AKT targets murine double minute 2, X-linked inhibitor of apoptosis, and forkhead box O1. This study demonstrates that anti-HER3 D1 and D3 Abs could represent a new option for immunotherapy of pancreatic and triple-negative breast cancers.

  5. Bifurcations of Baker domains

    Science.gov (United States)

    Lauber, Arnd

    2007-07-01

    We consider the family of transcendental entire functions given by \\{f_c:{\\mathbb C} \\rightarrow {\\mathbb C}:z-c+e^z, c \\in {\\mathbb C} \\} . If Re c > 0, then fc features a Baker domain as the only component of the Fatou set, while the functions fc show a different dynamical behaviour if c \\in \\rmi{\\mathbb R} . We describe the dynamical planes of these functions and show that the Julia sets converge in the limit process f_{c_1+\\rmi c_2} \\rightarrow f_{\\rmi c_2} with respect to the Hausdorff metric, where c_1 \\in {\\mathbb R}^+ and c_2 \\in {\\mathbb R} . We use this to show that Baker domains of any type (concerning a classification of König) are not necessarily stable under perturbation.

  6. Time Domain Induced Polarization

    DEFF Research Database (Denmark)

    Fiandaca, Gianluca; Auken, Esben; Christiansen, Anders Vest

    2012-01-01

    Time-domain-induced polarization has significantly broadened its field of reference during the last decade, from mineral exploration to environmental geophysics, e.g., for clay and peat identification and landfill characterization. Though, insufficient modeling tools have hitherto limited the use......%. Furthermore, the presence of low-pass filters in time-domain-induced polarization instruments affects the early times of the acquired decays (typically up to 100 ms) and has to be modeled in the forward response to avoid significant loss of resolution. The developed forward code has been implemented in a 1D...... polarization response when compared to traditional integral chargeability inversion. The quality of the inversion results has been assessed by a complete uncertainty analysis of the model parameters; furthermore, borehole information confirm the outcomes of the field interpretations. With this new accurate...

  7. Human epidermal growth factor receptor (HER-1:HER-3) Fc-mediated heterodimer has broad antiproliferative activity in vitro and in human tumor xenografts.

    Science.gov (United States)

    Sarup, Jay; Jin, Pei; Turin, Lisa; Bai, Xiaomei; Beryt, Malgorzata; Brdlik, Cathleen; Higaki, Jeffrey N; Jorgensen, Brett; Lau, Francis W; Lindley, Peter; Liu, Jim; Ni, Irene; Rozzelle, James; Kumari, Rajendra; Watson, Susan A; Zhang, Juan; Shepard, H Michael

    2008-10-01

    All four members of the human epidermal growth factor (EGF) receptor (HER) family are implicated in human cancers. Although efficacious in a subset of patients, resistance to single-targeted anti-HER therapy [i.e., cetuximab (Erbitux) and trastuzumab (Herceptin)] is often associated with coexpression of other HER family members. This may be overcome by a HER ligand binding molecule that sequesters multiple EGF-like ligands, preventing ligand-dependent receptor activation. Toward this end, we have combined the HER-1/EGFR and HER-3 ligand binding domains, dimerized with fusion of an Fc fragment of human IgG1. This resulted in a mixture of HER-1/Fc homodimer (HFD100), HER-3/Fc homodimer (HFD300), and HER-1/Fc:HER-3/Fc heterodimer (RB200), also termed Hermodulins. The purified first-generation RB200 bound EGF and neuregulin 1 (NRG1)-beta1 ligands, determined by cross-linking and direct binding studies. The binding affinity for both was approximately 10 nmol/L by dissociation-enhanced lanthanide fluorescence immunoassay using europium (Eu)-labeled ligands. Competition studies with RB200 using Eu-EGF or Eu-NRG1-beta1 revealed that RB200 bound HER-1 ligands, including transforming growth factor-alpha and heparin-binding EGF, and HER-3 ligands NRG1-alpha and NRG1-beta3. RB200 inhibited EGF- and NRG1-beta1-stimulated tyrosine phosphorylation of HER family proteins, proliferation of a diverse range of tumor cells in monolayer cell growth assays, tumor cell proliferation as a single agent and in synergy with tyrosine kinase inhibitors, lysophosphatidic acid-stimulated cell proliferation, and tumor growth in two human tumor xenograft nude mouse models. Taken together, the data reveal that RB200 has the potential to sequester multiple HER ligands and interfere with signaling by HER-1, HER-2, and HER-3.

  8. Partial domain wall partition functions

    National Research Council Canada - National Science Library

    Foda, O; Wheeler, M

    2012-01-01

    We consider six-vertex model configurations on an (n × N) lattice, n ≤ N, that satisfy a variation on domain wall boundary conditions that we define and call partial domain wall boundary conditions...

  9. Domain walls on the brane

    NARCIS (Netherlands)

    Bergshoeff, E; van der Schaar, JP; Papadopoulos, G

    1998-01-01

    We show that all branes admit worldvolume domain wall solutions. We find one class of solutions for which the tension of the brane changes discontinuously along the domain wall. These solutions are not supersymmetric. We argue that there is another class of domain wall solutions which is

  10. Feature-level domain adaptation

    DEFF Research Database (Denmark)

    Kouw, Wouter M.; Van Der Maaten, Laurens J P; Krijthe, Jesse H.

    2016-01-01

    Domain adaptation is the supervised learning setting in which the training and test data are sampled from different distributions: training data is sampled from a source domain, whilst test data is sampled from a target domain. This paper proposes and studies an approach, called feature...

  11. Metaphors, domains and embodiment

    Directory of Open Access Journals (Sweden)

    M.E. Botha

    2005-07-01

    Full Text Available Investigations of metaphorical meaning constitution and meaning (in- variance have revealed the significance of semantic and semiotic domains and the contexts within which they function as basis for the grounding of metaphorical meaning. In this article some of the current views concerning the grounding of metaphorical meaning in experience and embodiment are explored. My provisional agreement with Lakoff, Johnson and others about the “conceptual” nature of metaphor rests on an important caveat, viz. that this bodily based conceptual structure which lies at the basis of linguistic articulations of metaphor, is grounded in a deeper ontic structure of the world and of human experience. It is the “metaphorical” (actually “analogical” ontological structure of this grounding that is of interest for the line of argumentation followed in this article. Because Johnson, Lakoff and other’s proposal to ground metaphorical meaning in embodiment and neural processes is open to being construed as subjectivist and materialist, I shall attempt to articulate the contours of an alternative theory of conceptual metaphor, meaning and embodiment which counteracts these possibilities. This theory grounds metaphorical meaning and meaning change in an ontological and anthropological framework which recognises the presence and conditioning functioning of radially ordered structures for reality. These categorisations in which humankind, human knowledge and reality participate, condition and constrain (ground analogical and metaphorical meaning transfer, cross-domain mappings, and blends in cognition and in language, provide the basis for the analogical concepts found in these disciplines.

  12. On Probability Domains IV

    Science.gov (United States)

    Frič, Roman; Papčo, Martin

    2017-12-01

    Stressing a categorical approach, we continue our study of fuzzified domains of probability, in which classical random events are replaced by measurable fuzzy random events. In operational probability theory (S. Bugajski) classical random variables are replaced by statistical maps (generalized distribution maps induced by random variables) and in fuzzy probability theory (S. Gudder) the central role is played by observables (maps between probability domains). We show that to each of the two generalized probability theories there corresponds a suitable category and the two resulting categories are dually equivalent. Statistical maps and observables become morphisms. A statistical map can send a degenerated (pure) state to a non-degenerated one —a quantum phenomenon and, dually, an observable can map a crisp random event to a genuine fuzzy random event —a fuzzy phenomenon. The dual equivalence means that the operational probability theory and the fuzzy probability theory coincide and the resulting generalized probability theory has two dual aspects: quantum and fuzzy. We close with some notes on products and coproducts in the dual categories.

  13. On Probability Domains IV

    Science.gov (United States)

    Frič, Roman; Papčo, Martin

    2017-06-01

    Stressing a categorical approach, we continue our study of fuzzified domains of probability, in which classical random events are replaced by measurable fuzzy random events. In operational probability theory (S. Bugajski) classical random variables are replaced by statistical maps (generalized distribution maps induced by random variables) and in fuzzy probability theory (S. Gudder) the central role is played by observables (maps between probability domains). We show that to each of the two generalized probability theories there corresponds a suitable category and the two resulting categories are dually equivalent. Statistical maps and observables become morphisms. A statistical map can send a degenerated (pure) state to a non-degenerated one —a quantum phenomenon and, dually, an observable can map a crisp random event to a genuine fuzzy random event —a fuzzy phenomenon. The dual equivalence means that the operational probability theory and the fuzzy probability theory coincide and the resulting generalized probability theory has two dual aspects: quantum and fuzzy. We close with some notes on products and coproducts in the dual categories.

  14. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  15. Ligand binding by PDZ domains

    DEFF Research Database (Denmark)

    Chi, Celestine N.; Bach, Anders; Strømgaard, Kristian

    2012-01-01

    The postsynaptic density protein-95/disks large/zonula occludens-1 (PDZ) protein domain family is one of the most common protein-protein interaction modules in mammalian cells, with paralogs present in several hundred human proteins. PDZ domains are found in most cell types, but neuronal proteins......, for example, are particularly rich in these domains. The general function of PDZ domains is to bring proteins together within the appropriate cellular compartment, thereby facilitating scaffolding, signaling, and trafficking events. The many functions of PDZ domains under normal physiological as well...

  16. Domain architecture conservation in orthologs.

    Science.gov (United States)

    Forslund, Kristoffer; Pekkari, Isabella; Sonnhammer, Erik L L

    2011-08-05

    As orthologous proteins are expected to retain function more often than other homologs, they are often used for functional annotation transfer between species. However, ortholog identification methods do not take into account changes in domain architecture, which are likely to modify a protein's function. By domain architecture we refer to the sequential arrangement of domains along a protein sequence.To assess the level of domain architecture conservation among orthologs, we carried out a large-scale study of such events between human and 40 other species spanning the entire evolutionary range. We designed a score to measure domain architecture similarity and used it to analyze differences in domain architecture conservation between orthologs and paralogs relative to the conservation of primary sequence. We also statistically characterized the extents of different types of domain swapping events across pairs of orthologs and paralogs. The analysis shows that orthologs exhibit greater domain architecture conservation than paralogous homologs, even when differences in average sequence divergence are compensated for, for homologs that have diverged beyond a certain threshold. We interpret this as an indication of a stronger selective pressure on orthologs than paralogs to retain the domain architecture required for the proteins to perform a specific function. In general, orthologs as well as the closest paralogous homologs have very similar domain architectures, even at large evolutionary separation.The most common domain architecture changes observed in both ortholog and paralog pairs involved insertion/deletion of new domains, while domain shuffling and segment duplication/deletion were very infrequent. On the whole, our results support the hypothesis that function conservation between orthologs demands higher domain architecture conservation than other types of homologs, relative to primary sequence conservation. This supports the notion that orthologs are

  17. Domain architecture conservation in orthologs

    Science.gov (United States)

    2011-01-01

    Background As orthologous proteins are expected to retain function more often than other homologs, they are often used for functional annotation transfer between species. However, ortholog identification methods do not take into account changes in domain architecture, which are likely to modify a protein's function. By domain architecture we refer to the sequential arrangement of domains along a protein sequence. To assess the level of domain architecture conservation among orthologs, we carried out a large-scale study of such events between human and 40 other species spanning the entire evolutionary range. We designed a score to measure domain architecture similarity and used it to analyze differences in domain architecture conservation between orthologs and paralogs relative to the conservation of primary sequence. We also statistically characterized the extents of different types of domain swapping events across pairs of orthologs and paralogs. Results The analysis shows that orthologs exhibit greater domain architecture conservation than paralogous homologs, even when differences in average sequence divergence are compensated for, for homologs that have diverged beyond a certain threshold. We interpret this as an indication of a stronger selective pressure on orthologs than paralogs to retain the domain architecture required for the proteins to perform a specific function. In general, orthologs as well as the closest paralogous homologs have very similar domain architectures, even at large evolutionary separation. The most common domain architecture changes observed in both ortholog and paralog pairs involved insertion/deletion of new domains, while domain shuffling and segment duplication/deletion were very infrequent. Conclusions On the whole, our results support the hypothesis that function conservation between orthologs demands higher domain architecture conservation than other types of homologs, relative to primary sequence conservation. This supports the

  18. Protein domain organisation: adding order

    Directory of Open Access Journals (Sweden)

    Kummerfeld Sarah K

    2009-01-01

    Full Text Available Abstract Background Domains are the building blocks of proteins. During evolution, they have been duplicated, fused and recombined, to produce proteins with novel structures and functions. Structural and genome-scale studies have shown that pairs or groups of domains observed together in a protein are almost always found in only one N to C terminal order and are the result of a single recombination event that has been propagated by duplication of the multi-domain unit. Previous studies of domain organisation have used graph theory to represent the co-occurrence of domains within proteins. We build on this approach by adding directionality to the graphs and connecting nodes based on their relative order in the protein. Most of the time, the linear order of domains is conserved. However, using the directed graph representation we have identified non-linear features of domain organization that are over-represented in genomes. Recognising these patterns and unravelling how they have arisen may allow us to understand the functional relationships between domains and understand how the protein repertoire has evolved. Results We identify groups of domains that are not linearly conserved, but instead have been shuffled during evolution so that they occur in multiple different orders. We consider 192 genomes across all three kingdoms of life and use domain and protein annotation to understand their functional significance. To identify these features and assess their statistical significance, we represent the linear order of domains in proteins as a directed graph and apply graph theoretical methods. We describe two higher-order patterns of domain organisation: clusters and bi-directionally associated domain pairs and explore their functional importance and phylogenetic conservation. Conclusion Taking into account the order of domains, we have derived a novel picture of global protein organization. We found that all genomes have a higher than expected

  19. The Garrison Domain: Civil Military Relations in the Cyberspace Domain

    Science.gov (United States)

    2015-04-01

    governance, commerce , communications, and entertainment. The reliance on cyberspace is so predominant it seems unacceptable to not be part of the domain...Almost every type of person and organization on this planet arguably touches the cyberspace domain, directly or indirectly. Because this domain is...Department of Justice (DOJ) has also begun using cyberspace to gather information intelligence. Flying small civilian aircraft with electronic boxes to

  20. Mapping the Moral Domain

    Science.gov (United States)

    Graham, Jesse; Nosek, Brian A.; Haidt, Jonathan; Iyer, Ravi; Koleva, Spassena; Ditto, Peter H.

    2010-01-01

    The moral domain is broader than the empathy and justice concerns assessed by existing measures of moral competence, and it is not just a subset of the values assessed by value inventories. To fill the need for reliable and theoretically-grounded measurement of the full range of moral concerns, we developed the Moral Foundations Questionnaire (MFQ) based on a theoretical model of five universally available (but variably developed) sets of moral intuitions: Harm/care, Fairness/reciprocity, Ingroup/loyalty, Authority/respect, and Purity/sanctity. We present evidence for the internal and external validity of the scale and the model, and in doing so present new findings about morality: 1. Comparative model fitting of confirmatory factor analyses provides empirical justification for a five-factor structure of moral concerns. 2. Convergent/discriminant validity evidence suggests that moral concerns predict personality features and social group attitudes not previously considered morally relevant. 3. We establish pragmatic validity of the measure in providing new knowledge and research opportunities concerning demographic and cultural differences in moral intuitions. These analyses provide evidence for the usefulness of Moral Foundations Theory in simultaneously increasing the scope and sharpening the resolution of psychological views of morality. PMID:21244182

  1. Domain imaging in FINEMET ribbons

    Energy Technology Data Exchange (ETDEWEB)

    Silveyra, J.M., E-mail: jsilveyra@fi.uba.a [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, UBA-CONICET, Paseo Colon 850, (C1063ACV) Buenos Aires (Argentina); Vlasak, G.; Svec, P.; Janickovic, D. [Institute of Physics, Slovak Academy of Sciences, Dubravska cesta 9, 845 11 Bratislava (Slovakia); Cremaschi, V.J., E-mail: vcremas@gmail.co [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, UBA-CONICET, Paseo Colon 850, (C1063ACV) Buenos Aires (Argentina); Member of Carrera del Investigador, CONICET (Argentina)

    2010-09-15

    The magnetization behaviour of a ferromagnetic material depends on its domain structure, which in turn is largely determined by magnetic anisotropies. In this work, domain patterns were observed by a quite forgotten but still the simplest and the cheapest technique: the Bitter method. A systematic study of the evolution of the domain structure in FINEMET ribbons after thermal annealing is presented, correlating the results with the crystalline structure, magnetostriction and coercivity measurements.

  2. Summarization by domain ontology navigation

    DEFF Research Database (Denmark)

    Andreasen, Troels; Bulskov, Henrik

    2013-01-01

    A summary is a concise description that reflects the essence of a subject. A text, a collection of text documents, or a query answer can be summarized by simple means such as an automatically generated list of the most frequent words or “advanced” by a meaningful natural language description...... be a simple taxonomy or a generative domain ontology. A domain ontology can be provided by a preanalysis of a domain corpus and can be used to condense improved summaries that better reflects the conceptualization of a given domain....

  3. On Probability Domains

    Science.gov (United States)

    Frič, Roman; Papčo, Martin

    2010-12-01

    Motivated by IF-probability theory (intuitionistic fuzzy), we study n-component probability domains in which each event represents a body of competing components and the range of a state represents a simplex S n of n-tuples of possible rewards-the sum of the rewards is a number from [0,1]. For n=1 we get fuzzy events, for example a bold algebra, and the corresponding fuzzy probability theory can be developed within the category ID of D-posets (equivalently effect algebras) of fuzzy sets and sequentially continuous D-homomorphisms. For n=2 we get IF-events, i.e., pairs ( μ, ν) of fuzzy sets μ, ν∈[0,1] X such that μ( x)+ ν( x)≤1 for all x∈ X, but we order our pairs (events) coordinatewise. Hence the structure of IF-events (where ( μ 1, ν 1)≤( μ 2, ν 2) whenever μ 1≤ μ 2 and ν 2≤ ν 1) is different and, consequently, the resulting IF-probability theory models a different principle. The category ID is cogenerated by I=[0,1] (objects of ID are subobjects of powers I X ), has nice properties and basic probabilistic notions and constructions are categorical. For example, states are morphisms. We introduce the category S n D cogenerated by Sn=\\{(x1,x2,ldots ,xn)in In;sum_{i=1}nxi≤ 1\\} carrying the coordinatewise partial order, difference, and sequential convergence and we show how basic probability notions can be defined within S n D.

  4. The monocyte binding domain(s) on human immunoglobulin G.

    Science.gov (United States)

    Woof, J M; Nik Jaafar, M I; Jefferis, R; Burton, D R

    1984-06-01

    Monocyte binding has previously been assigned to the C gamma 3 domain of human immunoglobulin G (IgG) largely on the ability of the pFc' fragment to inhibit the monocyte-IgG interaction. This ability is markedly reduced compared to the intact parent IgG. We find this result with a conventional pFc' preparation but this preparation is found to contain trace contamination of parent IgG as demonstrated by reactivity with monoclonal antibodies directed against C gamma 2 domain and light-chain epitopes of human IgG. Extensive immunoaffinity purification of the pFc' preparation removes its inhibitory ability indicating that this originates in the trace contamination of parent IgG (or Fc). Neither of the human IgG1 paraproteins TIM, lacking the C gamma 2 domain, or SIZ, lacking the C gamma 3 domain, are found to inhibit the monocyte-IgG interaction. The hinge-deleted IgG1 Dob protein shows little or no inhibitory ability. Indirect evidence for the involvement of the C gamma 2 domain in monocyte binding is considered. We suggest finally that the site of interaction is found either on the C gamma 2 domain alone or between the C gamma 2 and C gamma 3 domains.

  5. Domain walls riding the wave.

    Energy Technology Data Exchange (ETDEWEB)

    Karapetrov, G.; Novosad, V.; Materials Science Division

    2010-11-01

    Recent years have witnessed a rapid proliferation of electronic gadgets around the world. These devices are used for both communication and entertainment, and it is a fact that they account for a growing portion of household energy consumption and overall world consumption of electricity. Increasing the energy efficiency of these devices could have a far greater and immediate impact than a gradual switch to renewable energy sources. The advances in the area of spintronics are therefore very important, as gadgets are mostly comprised of memory and logic elements. Recent developments in controlled manipulation of magnetic domains in ferromagnet nanostructures have opened opportunities for novel device architectures. This new class of memories and logic gates could soon power millions of consumer electronic devices. The attractiveness of using domain-wall motion in electronics is due to its inherent reliability (no mechanical moving parts), scalability (3D scalable architectures such as in racetrack memory), and nonvolatility (retains information in the absence of power). The remaining obstacles in widespread use of 'racetrack-type' elements are the speed and the energy dissipation during the manipulation of domain walls. In their recent contribution to Physical Review Letters, Oleg Tretiakov, Yang Liu, and Artem Abanov from Texas A&M University in College Station, provide a theoretical description of domain-wall motion in nanoscale ferromagnets due to the spin-polarized currents. They find exact conditions for time-dependent resonant domain-wall movement, which could speed up the motion of domain walls while minimizing Ohmic losses. Movement of domain walls in ferromagnetic nanowires can be achieved by application of external magnetic fields or by passing a spin-polarized current through the nanowire itself. On the other hand, the readout of the domain state is done by measuring the resistance of the wire. Therefore, passing current through the

  6. Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is increased in osteoarthritis and regulates chondrocyte catabolic and anabolic activities.

    Science.gov (United States)

    Long, D L; Ulici, V; Chubinskaya, S; Loeser, R F

    2015-09-01

    We determined if the epidermal growth factor receptor ligand HB-EGF is produced in cartilage and if it regulates chondrocyte anabolic or catabolic activity. HB-EGF expression was measured by quantitative PCR using RNA isolated from mouse knee joint tissues and from normal and osteoarthritis (OA) human chondrocytes. Immunohistochemistry was performed on normal and OA human cartilage and meniscus sections. Cultured chondrocytes were treated with fibronectin fragments (FN-f) as a catabolic stimulus and osteogenic protein 1 (OP-1) as an anabolic stimulus. Effects of HB-EGF on cell signaling were analyzed by immunoblotting of selected signaling proteins. MMP-13 was measured in conditioned media, proteoglycan synthesis was measured by sulfate incorporation, and matrix gene expression by quantitative PCR. HB-EGF expression was increased in 12-month old mice at 8 weeks after surgery to induce OA and increased amounts of HB-EGF were noted in human articular cartilage from OA knees. FN-f stimulated chondrocyte HB-EGF expression and HB-EGF stimulated chondrocyte MMP-13 production. However, HB-EGF was not required for FN-f stimulation of MMP-13 production. HB-EGF activated the ERK and p38 MAP kinases and stimulated phosphorylation of Smad1 at an inhibitory serine site which was associated with inhibition of OP-1 mediated proteoglycan synthesis and reduced aggrecan (ACAN) but not COL2A1 expression. HB-EGF is a new factor identified in OA cartilage that promotes chondrocyte catabolic activity while inhibiting anabolic activity suggesting it could contribute to the catabolic-anabolic imbalance seen in OA cartilage. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  7. RNA Aptamer Binds Heparin-Binding Epidermal Growth Factor-Like Growth Factor with High Affinity and Specificity and Neutralizes Its Activity

    Directory of Open Access Journals (Sweden)

    Masaki Yamato

    2017-09-01

    Conclusion: We identified a novel RNA aptamer that bound with high affinity and specificity to rhHB-EGF and potently inhibited the rhHB-EGF-mediated phosphorylation of EGFR. The anti-HB-EGF aptamer may be a promising therapeutic agent for specifically neutralizing HB-EGF signaling.

  8. Increased expression of heparin binding EGF (HB-EGF), amphiregulin, TGF alpha and epiregulin in androgen-independent prostate cancer cell lines.

    DEFF Research Database (Denmark)

    Tørring, Niels; Sørensen, Boe Sandahl; Nexø, Ebba

    2000-01-01

    RNA for the ligands TGF alpha, amphiregulin, HB-EGF and epiregulin were increased 10 to 100 fold in androgen-independent cells, as compared to LNCaP and PNT1A cells. Expression of mRNA for the ligands EGF and betacellulin and of the receptors HER1 and HER2 were similar in all lines investigated, except LNCaP cells...... which exhibit low expression of HER1. Similar results were obtained by ELISA. CONCLUSIONS: The data indicates a selective up-regulation of a subclass of ligands of the EGF-system in androgen-independent prostate cancer cell lines. We suggest this could be a mechanism to escape androgen dependence...

  9. Heparin-binding correlates with increased efficiency of AAV1- and AAV6-mediated transduction of striated muscle, but negatively impacts CNS transduction

    OpenAIRE

    Arnett, Andrea L. H.; Lisa R Beutler; Quintana, Albert; Allen, James; Finn, Eric; Richard D Palmiter; Chamberlain, Jeffrey S.

    2012-01-01

    Gene delivery vectors derived from adeno-associated virus (AAV) have great potential as therapeutic agents. rAAV1 and rAAV6, efficiently target striated muscle, but the mechanisms that determine their tropism remain unclear. It is known that AAV6, but not AAV1, interacts with heparin-sulfate proteoglycans (HSPG). HSPGs are not primary receptors for AAV6, but heparin interactions may affect tissue tropism and transduction. To investigate these possibilities, we generated rAAV1 and rAAV6 capsid...

  10. Identifying the functional part of heparin-binding protein (HBP) as a monocyte stimulator and the novel role of monocytes as HBP producers

    DEFF Research Database (Denmark)

    Schou, Morten; Djurup, René; Norris, Kjeld

    2011-01-01

    a crucial role when HBP binds to monocytes. We synthesized a 20-44 HBP peptide, cyclicized by a sulphur bridge, which encompasses this amino acid and functions as full-length HBP. Using a human monocyte cell line, we have shown that lipopolysaccharide (LPS)-triggered secretion of IL-6 is enhanced up to 10...

  11. DAML: domain adaptation metric learning.

    Science.gov (United States)

    Geng, Bo; Tao, Dacheng; Xu, Chao

    2011-10-01

    The state-of-the-art metric-learning algorithms cannot perform well for domain adaptation settings, such as cross-domain face recognition, image annotation, etc., because labeled data in the source domain and unlabeled ones in the target domain are drawn from different, but related distributions. In this paper, we propose the domain adaptation metric learning (DAML), by introducing a data-dependent regularization to the conventional metric learning in the reproducing kernel Hilbert space (RKHS). This data-dependent regularization resolves the distribution difference by minimizing the empirical maximum mean discrepancy between source and target domain data in RKHS. Theoretically, by using the empirical Rademacher complexity, we prove risk bounds for the nearest neighbor classifier that uses the metric learned by DAML. Practically, learning the metric in RKHS does not scale up well. Fortunately, we can prove that learning DAML in RKHS is equivalent to learning DAML in the space spanned by principal components of the kernel principle component analysis (KPCA). Thus, we can apply KPCA to select most important principal components to significantly reduce the time cost of DAML. We perform extensive experiments over four well-known face recognition datasets and a large-scale Web image annotation dataset for the cross-domain face recognition and image annotation tasks under various settings, and the results demonstrate the effectiveness of DAML. © 2011 IEEE

  12. The antibacterial activity of peptides derived from human beta-2 glycoprotein I is inhibited by protein H and M1 protein from Streptococcus pyogenes

    NARCIS (Netherlands)

    Nilsson, Maria; Wasylik, Sylwia; Mörgelin, Matthias; Olin, Anders I.; Meijers, Joost C. M.; Derksen, Ronald H. W. M.; de Groot, Philip G.; Herwald, Heiko

    2008-01-01

    During the last years, the importance of antibacterial peptides has attracted considerable attention. We report here that peptides derived from the fifth domain of beta-2 glycoprotein I (beta(2)GPI), a human heparin binding plasma protein, have antibacterial activities against Gram-positive and

  13. Fibronectin-cell interactions

    DEFF Research Database (Denmark)

    Couchman, J R; Austria, M R; Woods, A

    1990-01-01

    and both heparin-binding domains of the plasma fibronectin molecule and their interactions determined the type of adhesion. The same principle was seen in a study of the ability of plasma fibronectin to promote basement membrane assembly in an endodermal cell line, PF-HR9. There also, interactions of both...

  14. Predicting domain-domain interaction based on domain profiles with feature selection and support vector machines

    Directory of Open Access Journals (Sweden)

    Liao Li

    2010-10-01

    Full Text Available Abstract Background Protein-protein interaction (PPI plays essential roles in cellular functions. The cost, time and other limitations associated with the current experimental methods have motivated the development of computational methods for predicting PPIs. As protein interactions generally occur via domains instead of the whole molecules, predicting domain-domain interaction (DDI is an important step toward PPI prediction. Computational methods developed so far have utilized information from various sources at different levels, from primary sequences, to molecular structures, to evolutionary profiles. Results In this paper, we propose a computational method to predict DDI using support vector machines (SVMs, based on domains represented as interaction profile hidden Markov models (ipHMM where interacting residues in domains are explicitly modeled according to the three dimensional structural information available at the Protein Data Bank (PDB. Features about the domains are extracted first as the Fisher scores derived from the ipHMM and then selected using singular value decomposition (SVD. Domain pairs are represented by concatenating their selected feature vectors, and classified by a support vector machine trained on these feature vectors. The method is tested by leave-one-out cross validation experiments with a set of interacting protein pairs adopted from the 3DID database. The prediction accuracy has shown significant improvement as compared to InterPreTS (Interaction Prediction through Tertiary Structure, an existing method for PPI prediction that also uses the sequences and complexes of known 3D structure. Conclusions We show that domain-domain interaction prediction can be significantly enhanced by exploiting information inherent in the domain profiles via feature selection based on Fisher scores, singular value decomposition and supervised learning based on support vector machines. Datasets and source code are freely available on

  15. Wavefield extrapolation in pseudodepth domain

    KAUST Repository

    Ma, Xuxin

    2013-02-01

    Wavefields are commonly computed in the Cartesian coordinate frame. Its efficiency is inherently limited due to spatial oversampling in deep layers, where the velocity is high and wavelengths are long. To alleviate this computational waste due to uneven wavelength sampling, we convert the vertical axis of the conventional domain from depth to vertical time or pseudodepth. This creates a nonorthognal Riemannian coordinate system. Isotropic and anisotropic wavefields can be extrapolated in the new coordinate frame with improved efficiency and good consistency with Cartesian domain extrapolation results. Prestack depth migrations are also evaluated based on the wavefield extrapolation in the pseudodepth domain.© 2013 Society of Exploration Geophysicists. All rights reserved.

  16. Comparative Analysis of Protein Domain Organization

    OpenAIRE

    Ye, Yuzhen; Godzik, Adam

    2004-01-01

    We have developed a set of graph theory-based tools, which we call Comparative Analysis of Protein Domain Organization (CADO), to survey and compare protein domain organizations of different organisms. In the language of CADO, the organization of protein domains in a given organism is shown as a domain graph in which protein domains are represented as vertices, and domain combinations, defined as instances of two domains found in one protein, are represented as edges. CADO provides a new way ...

  17. Texture of lipid bilayer domains

    DEFF Research Database (Denmark)

    Jensen, Uffe Bernchou; Brewer, Jonathan R.; Midtiby, Henrik Skov

    2009-01-01

    which correlates with the phase state of the membrane. This is quantified by the generalized polarization (GP) function, and we demonstrate that a GP analysis can be performed on supported membranes. The results show that although the gel domains have heterogeneous texture, the membrane phase state does......We investigate the texture of gel (g) domains in binary lipid membranes composed of the phospholipids DPPC and DOPC. Lateral organization of lipid bilayer membranes is a topic of fundamental and biological importance. Whereas questions related to size and composition of fluid membrane domain...... are well studied, the possibility of texture in gel domains has so far not been examined. When using polarized light for two-photon excitation of the fluorescent lipid probe Laurdan, the emission intensity is highly sensitive to the angle between the polarization and the tilt orientation of lipid acyl...

  18. Fatou-Bieberbach domains in

    Science.gov (United States)

    Forstnerič, Franc; Wold, Erlend F.

    2015-10-01

    We construct Fatou-Bieberbach domains in for n>1 which contain a given compact set K and at the same time avoid a totally real affine subspace L of dimension < n, provided that K∪ L is polynomially convex. By using this result, we show that the domain for 1≤ k< n enjoys the basic Oka property with approximation for maps from any Stein manifold of dimension < n.

  19. Geometry of Homogeneous Bounded Domains

    CERN Document Server

    Vesentini, E

    2011-01-01

    This title includes: S.G. Gindikin, I.I. Pjateckii-Sapiro, E.B. Vinberg: Homogeneous Kahler manifolds; S.G. Greenfield: Extendibility properties of real submanifolds of Cn; W. Kaup: Holomorphische Abbildungen in Hyperbolische Raume; A. Koranyi: Holomorphic and harmonic functions on bounded symmetric domains; J.L. Koszul: Formes harmoniques vectorielles sur les espaces localement symetriques; S. Murakami: Plongements holomorphes de domaines symetriques; and E.M. Stein: The analogues of Fatous' theorem and estimates for maximal functions.

  20. Domain Decomposition Solvers for Frequency-Domain Finite Element Equations

    KAUST Repository

    Copeland, Dylan

    2010-10-05

    The paper is devoted to fast iterative solvers for frequency-domain finite element equations approximating linear and nonlinear parabolic initial boundary value problems with time-harmonic excitations. Switching from the time domain to the frequency domain allows us to replace the expensive time-integration procedure by the solution of a simple linear elliptic system for the amplitudes belonging to the sine- and to the cosine-excitation or a large nonlinear elliptic system for the Fourier coefficients in the linear and nonlinear case, respectively. The fast solution of the corresponding linear and nonlinear system of finite element equations is crucial for the competitiveness of this method. © 2011 Springer-Verlag Berlin Heidelberg.

  1. Functional domain walls in multiferroics.

    Science.gov (United States)

    Meier, Dennis

    2015-11-25

    During the last decade a wide variety of novel and fascinating correlation phenomena has been discovered at domain walls in multiferroic bulk systems, ranging from unusual electronic conductance to inseparably entangled spin and charge degrees of freedom. The domain walls represent quasi-2D functional objects that can be induced, positioned, and erased on demand, bearing considerable technological potential for future nanoelectronics. Most of the challenges that remain to be solved before turning related device paradigms into reality, however, still fall in the field of fundamental condensed matter physics and materials science. In this topical review seminal experimental findings gained on electric and magnetic domain walls in multiferroic bulk materials are addressed. A special focus is put on the physical properties that emerge at so-called charged domain walls and the added functionality that arises from coexisting magnetic order. The research presented in this review highlights that we are just entering a whole new world of intriguing nanoscale physics that is yet to be explored in all its details. The goal is to draw attention to the persistent challenges and identify future key directions for the research on functional domain walls in multiferroics.

  2. Inferring Domain-Domain Interactions from Protein-Protein Interactions with Formal Concept Analysis

    OpenAIRE

    Susan Khor

    2014-01-01

    Identifying reliable domain-domain interactions will increase our ability to predict novel protein-protein interactions, to unravel interactions in protein complexes, and thus gain more information about the function and behavior of genes. One of the challenges of identifying reliable domain-domain interactions is domain promiscuity. Promiscuous domains are domains that can occur in many domain architectures and are therefore found in many proteins. This becomes a problem for a method where t...

  3. Learning processes across knowledge domains

    DEFF Research Database (Denmark)

    Hall-Andersen, Lene Bjerg; Broberg, Ole

    2014-01-01

    Purpose - The purpose of this paper is to shed light on the problematics of learning across knowledge boundaries in organizational settings. The paper specifically explores learning processes that emerge, when a new knowledge domain is introduced into an existing organizational practice...... with the aim of creating a new combined practice. Design/methodology/approach - A case study was carried out as a "natural experiment" in an engineering consultancy, where emerging initiatives to integrate the newly acquired competencies into the existing practice were explored. A theoretical framework...... organization, it remained discrete in 'pockets' of learning; mainly at an individual level, at project level or as domain-specific learning. Learning processes were intertwined with elements of domain-specific interests, power, managerial support, structural conditions, material and epistemic differences...

  4. Domain similarity based orthology detection.

    Science.gov (United States)

    Bitard-Feildel, Tristan; Kemena, Carsten; Greenwood, Jenny M; Bornberg-Bauer, Erich

    2015-05-13

    Orthologous protein detection software mostly uses pairwise comparisons of amino-acid sequences to assert whether two proteins are orthologous or not. Accordingly, when the number of sequences for comparison increases, the number of comparisons to compute grows in a quadratic order. A current challenge of bioinformatic research, especially when taking into account the increasing number of sequenced organisms available, is to make this ever-growing number of comparisons computationally feasible in a reasonable amount of time. We propose to speed up the detection of orthologous proteins by using strings of domains to characterize the proteins. We present two new protein similarity measures, a cosine and a maximal weight matching score based on domain content similarity, and new software, named porthoDom. The qualities of the cosine and the maximal weight matching similarity measures are compared against curated datasets. The measures show that domain content similarities are able to correctly group proteins into their families. Accordingly, the cosine similarity measure is used inside porthoDom, the wrapper developed for proteinortho. porthoDom makes use of domain content similarity measures to group proteins together before searching for orthologs. By using domains instead of amino acid sequences, the reduction of the search space decreases the computational complexity of an all-against-all sequence comparison. We demonstrate that representing and comparing proteins as strings of discrete domains, i.e. as a concatenation of their unique identifiers, allows a drastic simplification of search space. porthoDom has the advantage of speeding up orthology detection while maintaining a degree of accuracy similar to proteinortho. The implementation of porthoDom is released using python and C++ languages and is available under the GNU GPL licence 3 at http://www.bornberglab.org/pages/porthoda .

  5. Domain specific MT in use

    DEFF Research Database (Denmark)

    Offersgaard, Lene; Povlsen, Claus; Almsten, Lisbeth Kjeldgaard

    2008-01-01

    point scale evaluate the sentence from the point of view of the post-editor. The post-editor profile defined by the LSP is based on the experiences of introducing MT in the LSP workflow. The relation between the Translation Edit Rate (TER) scores and “Usability” scores is tested. We find TER a candidate...... for an automatic metric simulating the post-editors’ usability judgements. LSP tests show 67% saved time in post-editing for the tested domain. Finally, the use of weighted sub-domain phrase tables in a SMT system is shown to improve translation quality....

  6. Domain Discretization and Circle Packings

    DEFF Research Database (Denmark)

    Dias, Kealey

    , and the edges are geodesic segments (Euclidean, hyperbolic, or spherical) connecting centers of circles that are tangent to each other. Three circles that are mutually tangent form a face of the triangulation. Since circle packing is closely related to triangulation, circle packing methods can be applied...... to domain discretization problems such as triangulation and unstructured mesh generation techniques. We wish to ask ourselves the question: given a cloud of points in the plane (we restrict ourselves to planar domains), is it possible to construct a circle packing preserving the positions of the vertices...

  7. Improving the performance of DomainDiscovery of protein domain boundary assignment using inter-domain linker index

    Directory of Open Access Journals (Sweden)

    Zomaya Albert Y

    2006-12-01

    Full Text Available Abstract Background Knowledge of protein domain boundaries is critical for the characterisation and understanding of protein function. The ability to identify domains without the knowledge of the structure – by using sequence information only – is an essential step in many types of protein analyses. In this present study, we demonstrate that the performance of DomainDiscovery is improved significantly by including the inter-domain linker index value for domain identification from sequence-based information. Improved DomainDiscovery uses a Support Vector Machine (SVM approach and a unique training dataset built on the principle of consensus among experts in defining domains in protein structure. The SVM was trained using a PSSM (Position Specific Scoring Matrix, secondary structure, solvent accessibility information and inter-domain linker index to detect possible domain boundaries for a target sequence. Results Improved DomainDiscovery is compared with other methods by benchmarking against a structurally non-redundant dataset and also CASP5 targets. Improved DomainDiscovery achieves 70% accuracy for domain boundary identification in multi-domains proteins. Conclusion Improved DomainDiscovery compares favourably to the performance of other methods and excels in the identification of domain boundaries for multi-domain proteins as a result of introducing support vector machine with benchmark_2 dataset.

  8. Overlap/Domain-wall reweighting

    Science.gov (United States)

    Fukaya, H.; Aoki, S.; Cossu, G.; Hashimoto, S.; Kaneko, T.; Noaki, J.

    We investigate the eigenvalues of nearly chiral lattice Dirac operators constructed with five-dimensional implementations. Allowing small violation of the Ginsparg-Wilson relation, the HMC simulation is made much faster while the eigenvalues are not significantly affected. We discuss the possibility of reweighting the gauge configurations generated with domain-wall fermions to those of exactly chiral lattice fermions.

  9. Life sciences domain analysis model.

    Science.gov (United States)

    Freimuth, Robert R; Freund, Elaine T; Schick, Lisa; Sharma, Mukesh K; Stafford, Grace A; Suzek, Baris E; Hernandez, Joyce; Hipp, Jason; Kelley, Jenny M; Rokicki, Konrad; Pan, Sue; Buckler, Andrew; Stokes, Todd H; Fernandez, Anna; Fore, Ian; Buetow, Kenneth H; Klemm, Juli D

    2012-01-01

    Meaningful exchange of information is a fundamental challenge in collaborative biomedical research. To help address this, the authors developed the Life Sciences Domain Analysis Model (LS DAM), an information model that provides a framework for communication among domain experts and technical teams developing information systems to support biomedical research. The LS DAM is harmonized with the Biomedical Research Integrated Domain Group (BRIDG) model of protocol-driven clinical research. Together, these models can facilitate data exchange for translational research. The content of the LS DAM was driven by analysis of life sciences and translational research scenarios and the concepts in the model are derived from existing information models, reference models and data exchange formats. The model is represented in the Unified Modeling Language and uses ISO 21090 data types. The LS DAM v2.2.1 is comprised of 130 classes and covers several core areas including Experiment, Molecular Biology, Molecular Databases and Specimen. Nearly half of these classes originate from the BRIDG model, emphasizing the semantic harmonization between these models. Validation of the LS DAM against independently derived information models, research scenarios and reference databases supports its general applicability to represent life sciences research. The LS DAM provides unambiguous definitions for concepts required to describe life sciences research. The processes established to achieve consensus among domain experts will be applied in future iterations and may be broadly applicable to other standardization efforts. The LS DAM provides common semantics for life sciences research. Through harmonization with BRIDG, it promotes interoperability in translational science.

  10. Frequency-Domain Transient Imaging.

    Science.gov (United States)

    Jingyu Lin; Yebin Liu; Jinli Suo; Qionghai Dai

    2017-05-01

    A transient image is the optical impulse response of a scene, which also visualizes the propagation of light during an ultra-short time interval. In contrast to the previous transient imaging which samples in the time domain using an ultra-fast imaging system, this paper proposes transient imaging in the frequency domain using a multi-frequency time-of-flight (ToF) camera. Our analysis reveals the Fourier relationship between transient images and the measurements of a multi-frequency ToF camera, and identifies the causes of the systematic error-non-sinusoidal and frequency-varying waveforms and limited frequency range of the modulation signal. Based on the analysis we propose a novel framework of frequency-domain transient imaging. By removing the systematic error and exploiting the harmonic components inside the measurements, we achieves high quality reconstruction results. Moreover, our technique significantly reduces the computational cost of ToF camera based transient image reconstruction, especially reduces the memory usage, such that it is feasible for the reconstruction of transient images at extremely small time steps. The effectiveness of frequency-domain transient imaging is tested on synthetic data, real data from the web, and real data acquired by our prototype camera.

  11. The Distributed-SDF Domain

    DEFF Research Database (Denmark)

    Cuadrado, Daniel Lázaro; Ravn, Anders Peter; Koch, Peter

    2005-01-01

    . Those relations are in charge of receiving the tokens and placing them at the right receiver. The same goes for the output ports. Tokens are sent over the net to the distributed processes that are expecting to receive them. The distributed-SDF domain provides certain advantages derived from its...

  12. Modules over discrete valuation domains

    CERN Document Server

    Tuganbaev, Askar A

    2008-01-01

    This book provides the first systematic treatment of modules over discrete valuation domains which plays an important role in various areas of algebra, especially in commutative algebra. Many important results representing the state of the art are presented in the text which is supplemented by exercises and interesting open problems. An important contribution to commutative algebra.

  13. Compiling Dictionaries Using Semantic Domains*

    Directory of Open Access Journals (Sweden)

    Ronald Moe

    2011-10-01

    Full Text Available

    Abstract: The task of providing dictionaries for all the world's languages is prodigious, re-quiring efficient techniques. The text corpus method cannot be used for minority languages lacking texts. To meet the need, the author has constructed a list of 1 600 semantic domains, which he has successfully used to collect words. In a workshop setting, a group of speakers can collect as many as 17 000 words in ten days. This method results in a classified word list that can be efficiently expanded into a full dictionary. The method works because the mental lexicon is a giant web or-ganized around key concepts. A semantic domain can be defined as an important concept together with the words directly related to it by lexical relations. A person can utilize the mental web to quickly jump from word to word within a domain. The author is developing a template for each domain to aid in collecting words and in de-scribing their semantics. Investigating semantics within the context of a domain yields many in-sights. The method permits the production of both alphabetically and semantically organized dic-tionaries. The list of domains is intended to be universal in scope and applicability. Perhaps due to universals of human experience and universals of linguistic competence, there are striking simi-larities in various lists of semantic domains developed for languages around the world. Using a standardized list of domains to classify multiple dictionaries opens up possibilities for cross-lin-guistic research into semantic and lexical universals.

    Keywords: SEMANTIC DOMAINS, SEMANTIC FIELDS, SEMANTIC CATEGORIES, LEX-ICAL RELATIONS, SEMANTIC PRIMITIVES, DOMAIN TEMPLATES, MENTAL LEXICON, SEMANTIC UNIVERSALS, MINORITY LANGUAGES, LEXICOGRAPHY

    Opsomming: Samestelling van woordeboeke deur gebruikmaking van se-mantiese domeine. Die taak van die voorsiening van woordeboeke aan al die tale van die wêreld is geweldig en vereis doeltreffende tegnieke. Die

  14. Domain relaxation in Langmuir films

    Science.gov (United States)

    Alexander, James C.; Bernoff, Andrew J.; Mann, Elizabeth K.; Mann, J. Adin; Wintersmith, Jacob R.; Zou, Lu

    We report on theoretical studies of molecularly thin Langmuir films on the surface of a quiescent subfluid and qualitatively compare the results to both new and previous experiments. The film covers the entire fluid surface, but domains of different phases are observed. In the absence of external forcing, the compact domains tend to relax to circles, driven by a line tension at the phase boundaries. When stretched (by a transient applied stagnation-point flow or by stirring), a compact domain elongates, creating a bola consisting of two roughly circular reservoirs connected by a thin tether. This shape will then relax slowly to the minimum-energy configuration of a circular domain. The tether is never observed to rupture, even when it is more than a hundred times as long as it is wide. We model these experiments by taking previous descriptions of the full hydrodynamics, identifying the dominant effects via dimensional analysis, and reducing the system to a more tractable form. The result is a free boundary problem for an inviscid Langmuir film whose motion is driven by the line tension of the domain and damped by the viscosity of the subfluid. Using this model we derive relaxation rates for perturbations of a uniform strip and a circular patch. We also derive a boundary integral formulation which allows an efficient numerical solution of the problem. Numerically this model replicates the formation of a bola and the subsequent relaxation observed in the experiments. Finally, we suggest physical properties of the system (such as line tension) that can be deduced by comparison of the theory and numerical simulations to the experiment. Two movies are available with the online version of the paper.

  15. Domains of Awareness in Schizophrenia

    Science.gov (United States)

    Gilleen, J.; Greenwood, K.; David, A. S.

    2011-01-01

    Patients with schizophrenia are often characterized as lacking insight or awareness into their illness and symptoms, yet despite considerable research, we still lack a full understanding of the factors involved in causing poor awareness. Within schizophrenia, there has been shown to be a fractionation across dimensions of awareness into mental illness: of being ill, of symptoms, and of treatment compliance. Recently, attention has turned to evidence of a fractionation between awareness of illness and of cognitive impairments and functioning. The current study investigated the degree of fractionation across a broad range of domains of function in schizophrenia and how each domain may be associated with neuropsychological functioning, clinical, mood, and demographic variables. Thirty-one mostly chronic stable patients with schizophrenia completed a battery of neuropsychological tests and measures of psychopathology, including mood. Cognitive insight and awareness of illness, symptoms, memory, and behavioral functioning were also measured. Insight and awareness were assessed using a combination of semistructured interview, observer-rated, self-rated, and objective measures, and included measures of the discrepancy between carer and self-ratings of impairment. Results revealed that awareness of functioning in each domain was largely independent and that awareness in each domain was predicted by different factors. Insight into symptoms was relatively poor while insight into cognitive deficits was preserved. Relative to neuropsychological variables, cognitive insight, comprising self-certainty and self-reflexivity, was a greater predictor of awareness. In conclusion, awareness is multiply fractionated and multiply determined. Therapeutic interventions could, therefore, produce beneficial changes within specific domains of awareness. PMID:20851850

  16. Inferring domain-domain interactions from protein-protein interactions with formal concept analysis.

    Directory of Open Access Journals (Sweden)

    Susan Khor

    Full Text Available Identifying reliable domain-domain interactions will increase our ability to predict novel protein-protein interactions, to unravel interactions in protein complexes, and thus gain more information about the function and behavior of genes. One of the challenges of identifying reliable domain-domain interactions is domain promiscuity. Promiscuous domains are domains that can occur in many domain architectures and are therefore found in many proteins. This becomes a problem for a method where the score of a domain-pair is the ratio between observed and expected frequencies because the protein-protein interaction network is sparse. As such, many protein-pairs will be non-interacting and domain-pairs with promiscuous domains will be penalized. This domain promiscuity challenge to the problem of inferring reliable domain-domain interactions from protein-protein interactions has been recognized, and a number of work-arounds have been proposed. This paper reports on an application of Formal Concept Analysis to this problem. It is found that the relationship between formal concepts provides a natural way for rare domains to elevate the rank of promiscuous domain-pairs and enrich highly ranked domain-pairs with reliable domain-domain interactions. This piggybacking of promiscuous domain-pairs onto less promiscuous domain-pairs is possible only with concept lattices whose attribute-labels are not reduced and is enhanced by the presence of proteins that comprise both promiscuous and rare domains.

  17. IMPLICATIONS OF CROSS DOMAIN FIRES IN MULTI-DOMAIN BATTLE

    Science.gov (United States)

    2017-04-06

    dimension of the battlefield. Where once the battlefield was objective’s based, it is now based on area control and is no longer restricted to the...Other adversaries like Russia are investing in research and development in fields such as directed energy weapons, rail guns , radio frequency weapons...advantage and control key terrain to consolidate gains.”12 Multi-Domain Battle integrates joint, interorganizational and multinational capabilities

  18. Statistical Mechanics of Time Domain Ensemble Learning

    OpenAIRE

    Miyoshi, Seiji; Uezu, Tatsuya; Okada, Masato

    2006-01-01

    Conventional ensemble learning combines students in the space domain. On the other hand, in this paper we combine students in the time domain and call it time domain ensemble learning. In this paper, we analyze the generalization performance of time domain ensemble learning in the framework of online learning using a statistical mechanical method. We treat a model in which both the teacher and the student are linear perceptrons with noises. Time domain ensemble learning is twice as effective ...

  19. GPI-anchored diphtheria toxin receptor allows membrane translocation of the toxin without detectable ion channel activity.

    OpenAIRE

    Lanzrein, M; Sand, O; Olsnes, S

    1996-01-01

    We have investigated the role of the transmembrane and cytoplasmic domains of the diphtheria toxin (DT) receptor [heparin-binding epidermal growth factor (HB-EGF) precursor] in the intoxication pathway. Two mutants were constructed in which these domains were replaced by either a 37 amino acid sequence signalling membrane attachment via a glycosylphosphatidylinositol (GPI) anchor (DTR-GPI) or by the transmembrane and cytoplasmic domains of the human EGF receptor (DTR-EGFR). Similar amounts of...

  20. Ubiquitin domain proteins in disease

    Directory of Open Access Journals (Sweden)

    Hartmann-Petersen Rasmus

    2007-11-01

    Full Text Available Abstract The human genome encodes several ubiquitin-like (UBL domain proteins (UDPs. Members of this protein family are involved in a variety of cellular functions and many are connected to the ubiquitin proteasome system, an essential pathway for protein degradation in eukaryotic cells. Despite their structural similarity, the UBL domains appear to have a range of different targets, resulting in a considerable diversity with respect to UDP function. Here, we give a short summary of the biochemical and physiological roles of the UDPs, which have been linked to human diseases including neurodegeneration and cancer. Publication history: Republished from Current BioData's Targeted Proteins database (TPdb; http://www.targetedproteinsdb.com.

  1. Gabor domain optical coherence microscopy

    Science.gov (United States)

    Murali, Supraja

    Time domain Optical Coherence Tomography (TD-OCT), first reported in 1991, makes use of the low temporal coherence properties of a NIR broadband laser to create depth sectioning of up to 2mm under the surface using optical interferometry and point to point scanning. Prior and ongoing work in OCT in the research community has concentrated on improving axial resolution through the development of broadband sources and speed of image acquisition through new techniques such as Spectral domain OCT (SD-OCT). In SD-OCT, an entire depth scan is acquired at once with a low numerical aperture (NA) objective lens focused at a fixed point within the sample. In this imaging geometry, a longer depth of focus is achieved at the expense of lateral resolution, which is typically limited to 10 to 20 mum. Optical Coherence Microscopy (OCM), introduced in 1994, combined the advantages of high axial resolution obtained in OCT with high lateral resolution obtained by increasing the NA of the microscope placed in the sample arm. However, OCM presented trade-offs caused by the inverse quadratic relationship between the NA and the DOF of the optics used. For applications requiring high lateral resolution, such as cancer diagnostics, several solutions have been proposed including the periodic manual re-focusing of the objective lens in the time domain as well as the spectral domain C-mode configuration in order to overcome the loss in lateral resolution outside the DOF. In this research, we report for the first time, high speed, sub-cellular imaging (lateral resolution of 2 mum) in OCM using a Gabor domain image processing algorithm with a custom designed and fabricated dynamic focus microscope interfaced to a Ti:Sa femtosecond laser centered at 800 nm within an SD-OCM configuration. It is envisioned that this technology will provide a non-invasive replacement for the current practice of multiple biopsies for skin cancer diagnosis. The research reported here presents three important advances

  2. Domains of bosonic functional integrals

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, Luiz C.L. [Universidade Federal Rural do Rio de Janeiro, RJ (Brazil). Dept. de Fisica]|[Para Univ., Belem, PA (Brazil). Dept. de Fisica

    1998-07-01

    We propose a mathematical framework for bosonic Euclidean quantum field functional integrals based on the theory of integration on the dual algebraic vector space of classical field sources. We present a generalization of the Minlos-Dao Xing theorem and apply it to determine exactly the domain of integration associated to the functional integral representation of the two-dimensional quantum electrodynamics Schwinger generating functional. (author)

  3. Categorization in the Affective Domain

    DEFF Research Database (Denmark)

    Sauciuc, Gabriela-Alina

    2011-01-01

    Data collected in Romance and Scandinavian languages (N=474) in a superordinate category name production task indicate that a multiple-strategy approach would be more suitable for accounting of categorization in the affective domain instead of a prototype approach as suggested by previous studies....... This paper will highlight performance aspects which appear to be consistent with such an interpretation, as well as an important layman- expert knowledge asymmetry in affective categorization....

  4. Ubiquitin domain proteins in disease

    DEFF Research Database (Denmark)

    Klausen, Louise Kjær; Schulze, Andrea; Seeger, Michael

    2007-01-01

    their structural similarity, the UBL domains appear to have a range of different targets, resulting in a considerable diversity with respect to UDP function. Here, we give a short summary of the biochemical and physiological roles of the UDPs, which have been linked to human diseases including neurodegeneration...... and cancer. Publication history: Republished from Current BioData's Targeted Proteins database (TPdb; http://www.targetedproteinsdb.com)....

  5. Superconductivity in domains with corners

    DEFF Research Database (Denmark)

    Bonnaillie-Noel, Virginie; Fournais, Søren

    2007-01-01

    We study the two-dimensional Ginzburg-Landau functional in a domain with corners for exterior magnetic field strengths near the critical field where the transition from the superconducting to the normal state occurs. We discuss and clarify the definition of this field and obtain a complete...... asymptotic expansion for it in the large $\\kappa$ regime. Furthermore, we discuss nucleation of superconductivity at the boundary....

  6. A Domain Specific DSP Processor

    OpenAIRE

    Tell, Eric

    2001-01-01

    This thesis describes the design of a domain specific DSP processor. The thesis is divided into two parts. The first part gives some theoretical background, describes the different steps of the design process (both for DSP processors in general and for this project) and motivates the design decisions made for this processor. The second part is a nearly complete design specification. The intended use of the processor is as a platform for hardware acceleration units. Support for this has howe...

  7. Beyond cross-domain learning: Multiple-domain nonnegative matrix factorization

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-02-01

    Traditional cross-domain learning methods transfer learning from a source domain to a target domain. In this paper, we propose the multiple-domain learning problem for several equally treated domains. The multiple-domain learning problem assumes that samples from different domains have different distributions, but share the same feature and class label spaces. Each domain could be a target domain, while also be a source domain for other domains. A novel multiple-domain representation method is proposed for the multiple-domain learning problem. This method is based on nonnegative matrix factorization (NMF), and tries to learn a basis matrix and coding vectors for samples, so that the domain distribution mismatch among different domains will be reduced under an extended variation of the maximum mean discrepancy (MMD) criterion. The novel algorithm - multiple-domain NMF (MDNMF) - was evaluated on two challenging multiple-domain learning problems - multiple user spam email detection and multiple-domain glioma diagnosis. The effectiveness of the proposed algorithm is experimentally verified. © 2013 Elsevier Ltd. All rights reserved.

  8. Structuring very large domain models

    DEFF Research Database (Denmark)

    Störrle, Harald

    2010-01-01

    at a lower level of detail have not been dealt with. This paper aims at filling this gap by reporting personal experiences from a very large scale industrial domain modeling project. There, structuring the logical view turned out to be a critical success factor. We explain the project and its setting......, analyze the role and repercussions of model structuring, and examine the implications model structuring decisions have on other parts of the project. We then explain the model structure abstracted from a very large scale industrial modeling project. Finally, we discuss lessons learned....

  9. Domain Building or Risk Taking

    DEFF Research Database (Denmark)

    Hjort, Katrin; Abrahamsen, Marianne

    2012-01-01

    of the relations between gender, values and family obligation but reveals an interesting difference between two strategies for career development: Domain Building and Risk Taking. Both strategies are applied by both men and women. However, one of them seems to be the most effective with regard to achieve......The Nordic Countries are usually seen as the worlds must successful nations when it comes to gender equality, and the Scandinavian population in general appreciates values traditionally labeled feminine as caretaking and the quality of everyday life. However, the inequalities become obvious...

  10. The domain Green's function method

    Science.gov (United States)

    Moskowitz, Jules W.; Schmidt, K. E.

    1986-09-01

    An implementation of the domain Green's function Monte Carlo algorithm is described. Unlike the short time approximation, the method is variational and exact within the limits of the fixed node approximation. The systems investigated include LiH, Be in the ground and first excited states, a study of the C2v insertion pathway of Be into H2, and H2O. We predict a barrier of 0.190 hartree for the insertion reaction with a statistical accuracy of ±2%. Better than 90% of the correlation energy is recovered in each case, which makes these some of the most accurate computations to date.

  11. The Promise of Domain Adaptation

    Science.gov (United States)

    Mahabal, Ashish A.; Li, Jingling; Vaijanapurkar, Samarth; Bue, Brian; Miller, Adam; Donalek, Ciro; Djorgovski, Stanislav G.; Drake, Andrew J.; Graham, Matthew; CRTS, iPTF

    2016-01-01

    Most new surveys spend an appreciable time in collecting data on which to train classifiers before they can be used on future observations from the same dataset. The result generating phase can start much earlier if the training could incorporate data accumulated from older surveys enhanced with a small set from the new survey. This is exactly what Domain Adaptation (DA) allows us to do. The main idea behind DAs can be summarized thus: if we have two classes of separable objects in some feature space of a Source survey (S), we can define a hyperplane to separate the two types. In a second Target survey (T), for the same features the hyperplane would be inclined differently. DA methods get the mapping between the two hyperplanes using a small fraction of data from the Target (T) survey and can then be used to predict the classes of the remaining majority of data in T. We discuss the parameters that need to be tuned, the difficulties involved, and ways to improve the results. As we move towards bigger, and deeper surveys, being able to use existing labelled information to conduct classification in future surveys will be more cost-effective and promote time efficiency as well. Starting with the light curve data of 50,000 periodic objects from Catalina Real-Time Transient Survey (CRTS), we have applied domain adaptation techniques such as Geodesic Flow Kernel (GFK) with Random forest classifier and Co-training for domain adaptation (CODA) to the CRTS data which has 35,000 points overlapping with Palomar Transient Factory (PTF), and 12,000 with Lincoln Near-Earth Asteroid Research (LINEAR). The results suggest that domain adaptation is an area worth exploring as the knowledge between these surveys is transferable and the approaches to find the mappings between these surveys can be applied to the remaining data as well as for near future surveys such as CRTS-II, Zwicky Transient Facility (ZTF) and the Large Synoptic Survey Telescope (LSST) to name a few at the optical

  12. Enhanced functional and structural domain assignments using ...

    Indian Academy of Sciences (India)

    Unknown

    ) by Seema Namboori, Natasha Mhatre, Sentivel Sujatha,. Narayanaswamy Srinivasan and Shashi Bhushan Pandit. The three-dimensional structure and subcellular localization of various domains and sub-domains of. Rv1318c, a putative ...

  13. Compiling dictionaries using semantic domains | Moe | Lexikos

    African Journals Online (AJOL)

    larities in various lists of semantic domains developed for languages around the world. Using a standardized list of domains to classify multiple dictionaries opens up possibilities for cross-lin-guistic research into semantic and lexical universals.

  14. The Private Legal Governance of Domain Names

    DEFF Research Database (Denmark)

    Schovsbo, Jens Hemmingsen

    2016-01-01

    ) and the Danish Complaints Board for Internet Domain Names (the Board) to discuss how and to what extent the domain name system balances interests between trademark owners and other users of domain names and secures the rule of law (legal certainty and predictability) with a special focus on cases where...... trademarks are used as (parts of) domain names to express criticism of the trademark holder or the trademark itself (e.g. “TMsucks.com” / “lorteTM.dk”)....

  15. Teaching-Learning in the Affective Domain

    Science.gov (United States)

    Holt, Brett J.; Hannon, James C.

    2006-01-01

    Affect is an important domain in which children learn. The affective domain of learning in physical education focuses on feelings, values, social behavior, and attitudes as they relate to human movement. Learning in the affective domain in physical education means that students learn such concepts as sportsmanship, "fair play," respect for others,…

  16. On the structure of order domains

    DEFF Research Database (Denmark)

    Geil, Olav; Pellikaan, Ruud

    2002-01-01

    The notion of an order domain is generalized. The behaviour of an order domain by taking a subalgebra, the extension of scalars, and the tensor product is studied. The relation of an order domain with valuation theory, Gröbner algebras, and graded structures is given. The theory of Gröbner bases...

  17. A Domain Standard for Land Administration

    NARCIS (Netherlands)

    Lemmen, C.; Van Oosterom, P.; Van der Molen, P.

    2013-01-01

    This paper presents the design of a Domain Model for Land Administration (LA). As a result a formal International Standard is available: ISO 19152 Geographic Information – Land Administration Domain Model (LADM) (ISO, 2012). Domain specific standardisation is needed to capture the semantics of the

  18. implementation of spatial domain homomorphic filtering

    African Journals Online (AJOL)

    eobe

    There is a lot of background literature on frequency- domain Homomorphic ... developed in the literature [4-6, 8-9]. This paper ..... Processing times for spatial and frequency domain filter. Colour Image Dimensions Spatial domain processing time(s) Frequency domainprocessing time(s). Girl. 256 × 256. 0.058. 0.914. Swan.

  19. Implementation of Spatial Domain Homomorphic Filtering on ...

    African Journals Online (AJOL)

    This paper describes the analysis of the Homomorphic filtering algorithm, the equivalency between the frequency and spatial-domain methods and the implementation of low-pass and high-pass spatial domain Homomorphic filter in low power embedded devices. It is shown that the Homomorphic filter in the spatial domain ...

  20. $\\omega$-Euclidean domain and Laurent series

    Directory of Open Access Journals (Sweden)

    O. M. Romaniv

    2016-06-01

    Full Text Available It is proved that a commutative domain $R$ is $\\omega$-Euclidean if and only if the ring of formal Laurent series over $R$ is $\\omega$-Euclidean domain. It is also proved that every singular matrice over ring of formal Laurent series $R_{X}$ are products of idempotent matrices if $R$ is $\\omega$ -Euclidean domain.

  1. Static domain wall in braneworld gravity

    Energy Technology Data Exchange (ETDEWEB)

    Abdalla, M.C.B.; Carlesso, P.F. [UNESP, Universidade Estadual Paulista, Instituto de Fisica Teiorica, Rua Dr. Bento Teobaldo Ferraz 271, Bloco II, Barra-Funda, Caixa Postal 70532-2, Sao Paulo, SP (Brazil); Hoff da Silva, J.M. [UNESP, Universidade Estadual Paulista, Departamento de Fisica e Quimica, Guaratingueta, SP (Brazil)

    2014-01-15

    In this paper we consider a static domain wall inside a 3-brane. Different from the standard achievement obtained in General Relativity, the analysis performed here gives a consistency condition for the existence of static domain walls in a braneworld gravitational scenario. Also the behavior of the domain wall's gravitational field in the newtonian limit is shown. (orig.)

  2. Latent domain models for statistical machine translation

    NARCIS (Netherlands)

    Hoàng, C.

    2017-01-01

    A data-driven approach to model translation suffers from the data mismatch problem and demands domain adaptation techniques. Given parallel training data originating from a specific domain, training an MT system on the data would result in a rather suboptimal translation for other domains. But does

  3. Domain Adaption Based on ELM Autoencoder

    National Research Council Canada - National Science Library

    Wan-Yu Deng; Yu-Tao Qu; Qian Zhang

    2017-01-01

      We propose a new ELM Autoencoder (ELM-AE) based domain adaption algorithm which describes the subspaces of source and target domain by ELM-AE and then carries out subspace alignment to project different domains into a common new space...

  4. One Health Core Competency Domains

    Directory of Open Access Journals (Sweden)

    Rebekah Frankson

    2016-09-01

    Full Text Available The emergence of complex global challenges at the convergence of human, animal, and environmental health has catalyzed a movement supporting ‘One Health’ approaches. Despite recognition of the importance of One Health approaches to address these complex challenges, little effort has been directed at identifying the seminal knowledge, skills and attitudes necessary for individuals to successfully contribute to One Health efforts. Between 2008 and 2011, three groups independently embarked on separate initiatives to identify core competencies for professionals involved with One Health approaches. Core competencies were considered critically important for guiding curriculum development and continuing professional education as they describe the knowledge, skills and attitudes required to be effective. A workshop was convened in 2012 to synthesize the various strands of work on One Health competencies. Despite having different mandates, participants, and approaches, all of these initiatives identified similar core competency domains: management; communication and informatics; values and ethics; leadership; teams and collaboration; roles and responsibilities; and systems thinking. These core competency domains have been used to develop new continuing professional education programs for One Health professionals and help university curricula prepare new graduates to be able to contribute more effectively to One Health approaches.

  5. On watermarking in frequency domain

    Science.gov (United States)

    Dasre, Narendrakumar Ramchandra; Patil, Hemraj Ramdas

    2010-02-01

    A wavelet-based image watermarking scheme is proposed, based on insertion of 'logo' image as watermark in midfrequency domain. This new approach provides flexibility in determining the pixel to be watermarked and increases the data hiding capacity. It is easy to implement watermark embedding algorithm as well as the corresponding detection algorithm. The watermarking algorithm is tested under different attacks such as median filtering, image cropping and image compression. It is also robust. The experimental results prove that the method is more tamper proof and less perceptible for any type of images other than well known private methods in frequency domain. In the proposed approach, an original image is decomposed into wavelet coefficients then watermark is embedded through algorithm. The wavelet transform filters can be used as security key for the extraction of inserted watermark. The proposed watermark extraction technique is independent of the original image. The watermark embedded image is produced by taking the inverse 2-D discrete wavelet transform of the altered wavelet decomposition. Here we have given the relation between the area of the channel in which we insert the watermark and the area affected in original image.

  6. Domain adaptation via transfer component analysis.

    Science.gov (United States)

    Pan, Sinno Jialin; Tsang, Ivor W; Kwok, James T; Yang, Qiang

    2011-02-01

    Domain adaptation allows knowledge from a source domain to be transferred to a different but related target domain. Intuitively, discovering a good feature representation across domains is crucial. In this paper, we first propose to find such a representation through a new learning method, transfer component analysis (TCA), for domain adaptation. TCA tries to learn some transfer components across domains in a reproducing kernel Hilbert space using maximum mean miscrepancy. In the subspace spanned by these transfer components, data properties are preserved and data distributions in different domains are close to each other. As a result, with the new representations in this subspace, we can apply standard machine learning methods to train classifiers or regression models in the source domain for use in the target domain. Furthermore, in order to uncover the knowledge hidden in the relations between the data labels from the source and target domains, we extend TCA in a semisupervised learning setting, which encodes label information into transfer components learning. We call this extension semisupervised TCA. The main contribution of our work is that we propose a novel dimensionality reduction framework for reducing the distance between domains in a latent space for domain adaptation. We propose both unsupervised and semisupervised feature extraction approaches, which can dramatically reduce the distance between domain distributions by projecting data onto the learned transfer components. Finally, our approach can handle large datasets and naturally lead to out-of-sample generalization. The effectiveness and efficiency of our approach are verified by experiments on five toy datasets and two real-world applications: cross-domain indoor WiFi localization and cross-domain text classification.

  7. Word Domain Disambiguation via Word Sense Disambiguation

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Tratz, Stephen C.; Gregory, Michelle L.

    2006-06-04

    Word subject domains have been widely used to improve the perform-ance of word sense disambiguation al-gorithms. However, comparatively little effort has been devoted so far to the disambiguation of word subject do-mains. The few existing approaches have focused on the development of al-gorithms specific to word domain dis-ambiguation. In this paper we explore an alternative approach where word domain disambiguation is achieved via word sense disambiguation. Our study shows that this approach yields very strong results, suggesting that word domain disambiguation can be ad-dressed in terms of word sense disam-biguation with no need for special purpose algorithms.

  8. Ferroelectric domain continuity over grain boundaries

    DEFF Research Database (Denmark)

    Mantri, Sukriti; Oddershede, Jette; Damjanovic, Dragan

    2017-01-01

    Formation and mobility of domain walls in ferroelectric materials is responsible for many of their electrical and mechanical properties. Domain wall continuity across grain boundaries has been observed since the 1950's and is speculated to affect the grain boundary-domain interactions, thereby...... orientation. We have also incorporated the effect of grain boundary ferroelectric polarization charge created when any two domains meet at the grain boundary plane. The probability of domain wall continuity for three specific grain misorientations is studied. Use of this knowledge to optimize processing...

  9. Blocking-resistant communication through domain fronting

    Directory of Open Access Journals (Sweden)

    Fifield David

    2015-06-01

    Full Text Available We describe “domain fronting,” a versatile censorship circumvention technique that hides the remote endpoint of a communication. Domain fronting works at the application layer, using HTTPS, to communicate with a forbidden host while appearing to communicate with some other host, permitted by the censor. The key idea is the use of different domain names at different layers of communication. One domain appears on the “outside” of an HTTPS request—in the DNS request and TLS Server Name Indication—while another domain appears on the “inside”—in the HTTP Host header, invisible to the censor under HTTPS encryption. A censor, unable to distinguish fronted and nonfronted traffic to a domain, must choose between allowing circumvention traffic and blocking the domain entirely, which results in expensive collateral damage. Domain fronting is easy to deploy and use and does not require special cooperation by network intermediaries. We identify a number of hard-to-block web services, such as content delivery networks, that support domain-fronted connections and are useful for censorship circumvention. Domain fronting, in various forms, is now a circumvention workhorse. We describe several months of deployment experience in the Tor, Lantern, and Psiphon circumvention systems, whose domain-fronting transports now connect thousands of users daily and transfer many terabytes per month.

  10. Impact of domain analysis on reuse methods

    Science.gov (United States)

    Gilroy, Kathy

    1989-01-01

    The SPS is performing a study for the U.S. Army CECOM on the impact of domain analysis on reuse methods. Domain analysis is the first activity that should be performed in the development of reusable software. It identifies the commonalities between systems within a given problem (such as navigation systems or database management). In the software arena these commonalities are implemented as software components that can be reused by new systems within that application domain. The objectives of the study are to develop an approach that makes domain analysis practical and effective for the Army, to reinforce the importance of domain analysis for software reuse programs, and to summarize and coalesce domain analysis information into a single reference source. Existing methods and tools are being analyzed, critical issues identified, and key automation issues addressed. Based on these, a methodology and set of guidelines for domain analysis are being developed. Potential automated tools will be identified for each activity in the methodology.

  11. Penerapan Microskills dalam Domain Multicultural

    Directory of Open Access Journals (Sweden)

    Happy Karlina Marjo

    2013-03-01

    Full Text Available Konselor multikultural menggunakan microskills yang bertujuan untuk memodifikasi interaksi konselor dalam membuat perbedaan yang signifikan pada kehidupan konseli dengan: (1 mengidentifikasi faktor-faktor dari respon nonverbal untuk diri konselor sendiri dan konseli, (2 memahami dasar intervieu microskills dalam proses menerima (attending, mendengarkan (listening, dan mempengaruhi (influencing, serta dampak potensial pada konseli untuk berubah, (3 mencatat fokus microskills, dan perhatian secara selektif yang merupakan dasar untuk masalah keluarga dan konseling multikultural, (4 mengetahui bagaimana dan kapan menggunakan konfrontasi microskill, dan (5 mengetahui keterampilan intervieu sebagai acuan frame multikultural. Sedangkan domain kompetensi konseling multikultural untuk pendidikan dan praktek, antara lain: (1 Counselor Awareness of Own Cultural Values and Biases, (2 Counselor Awareness of Client’ Worldview, dan (3 Culturally Appropriate Intervention Strategies.

  12. Structure and Function of KH Domains

    Energy Technology Data Exchange (ETDEWEB)

    Valverde, R.; Regan, E

    2008-01-01

    The hnRNP K homology (KH) domain was first identified in the protein human heterogeneous nuclear ribonucleoprotein K (hnRNP K) 14 years ago. Since then, KH domains have been identified as nucleic acid recognition motifs in proteins that perform a wide range of cellular functions. KH domains bind RNA or ssDNA, and are found in proteins associated with transcriptional and translational regulation, along with other cellular processes. Several diseases, e.g. fragile X mental retardation syndrome and paraneoplastic disease, are associated with the loss of function of a particular KH domain. Here we discuss the progress made towards understanding both general and specific features of the molecular recognition of nucleic acids by KH domains. The typical binding surface of KH domains is a cleft that is versatile but that can typically accommodate only four unpaired bases. Van der Waals forces and hydrophobic interactions and, to a lesser extent, electrostatic interactions, contribute to the nucleic acid binding affinity. 'Augmented' KH domains or multiple copies of KH domains within a protein are two strategies that are used to achieve greater affinity and specificity of nucleic acid binding. Isolated KH domains have been seen to crystallize as monomers, dimers and tetramers, but no published data support the formation of noncovalent higher-order oligomers by KH domains in solution. Much attention has been given in the literature to a conserved hydrophobic residue (typically Ile or Leu) that is present in most KH domains. The interest derives from the observation that an individual with this Ile mutated to Asn, in the KH2 domain of fragile X mental retardation protein, exhibits a particularly severe form of the syndrome. The structural effects of this mutation in the fragile X mental retardation protein KH2 domain have recently been reported. We discuss the use of analogous point mutations at this position in other KH domains to dissect both structure and

  13. Trafficking defects in PAS domain mutant Kv11.1 channels: roles of reduced domain stability and altered domain-domain interactions.

    Science.gov (United States)

    Ke, Ying; Ng, Chai Ann; Hunter, Mark J; Mann, Stefan A; Heide, Juliane; Hill, Adam P; Vandenberg, Jamie I

    2013-08-15

    Loss of Kv11.1 potassium channel function is the underlying cause of pathology in long-QT syndrome type 2, one of the commonest causes of sudden cardiac death in the young. Previous studies have identified the cytosolic PAS (Per/Arnt/Sim) domain as a hotspot for mutations that cause Kv11.1 trafficking defects. To investigate the underlying basis of this observation, we have quantified the effect of mutants on domain folding as well as interactions between the PAS domain and the remainder of the channel. Apart from R56Q, all mutants impaired the thermostability of the isolated PAS domain. Six mutants, located in the vicinity of a hydrophobic patch on the PAS domain surface, also affected binding of the isolated PAS domain to an N-terminal truncated hERG (human ether-a-go-go-related gene) channel. Conversely, four other surface mutants (C64Y, T65P, A78P and I96T) and one buried mutant (L86R) did not prevent the isolated PAS domain binding to the truncated channels. Our results highlight a critical role for interactions between the PAS domain and the remainder of the channel in the hERG assembly and that mutants that affect PAS domain interactions with the remainder of the channel have a more severe trafficking defect than that caused by domain unfolding alone.

  14. On Domain Registries and Website Content

    DEFF Research Database (Denmark)

    Schwemer, Sebastian Felix

    2018-01-01

    The link of lawful domain names to unlawful content is a phenomenon that until recently has not been very topical. Traditionally, domain registries have been off the radar of content-related debates. Enforcement efforts, public discourse and academic research have focused on other intermediaries...... such as Internet access service providers, hosting platforms, and websites that link to content. This article shows that in recent years, however, that the (secondary) liability of domain registries and registrars, and more specifically country code top-level domain registries (ccTLDs) for website content, has...... been tested in several EU Member States. The article investigates tendencies in the national lower-court jurisprudence and explores to what extent the liability exemption regime of the E-Commerce Directive applies to domain registries. The analysis concludes that whereas domain registries fall under...

  15. Juridical Regime of the Public Domain

    Directory of Open Access Journals (Sweden)

    Vasilica Negruţ

    2009-06-01

    Full Text Available The goods that form the administrative domain are classified in two categories: some to whichthe private law rules can be applied, some others meant for public use, unliable of individual approach,forming the public domain. The term of juridical regime of the public domain has in view the assembly ofrules that can be applied to the goods belonging to the public domain as well as the juridical relations bornbetween the owners of these goods and third persons. The public property goods are subjected exclusivelyto a juridical regime by public law, while the private property goods belonging to the public domain aregoverned simultaneously by two types of juridical regimes and more exactly by a mixed juridical regimeby common right and by power. The principles that can be applied to the public domain goods are: theinalienability, the imprescriptibility and the imperceptibility.

  16. Domains in Ferroic Crystals and Thin Films

    CERN Document Server

    Tagantsev, Alexander K; Fousek, Jan

    2010-01-01

    Domains in Ferroic Crystals and Thin Films presents experimental findings and theoretical understanding of ferroic (non-magnetic) domains developed during the past 60 years. It addresses the situation by looking specifically at bulk crystals and thin films, with a particular focus on recently-developed microelectronic applications and methods for observation of domains with techniques such as scanning force microscopy, polarized light microscopy, scanning optical microscopy, electron microscopy, and surface decorating techniques. Domains in Ferroic Crystals and Thin Films covers a large area of material properties and effects connected with static and dynamic properties of domains, which are extremely relevant to materials referred to as ferroics. In most solid state physics books, one large group of ferroics is customarily covered: those in which magnetic properties play a dominant role. Numerous books are specifically devoted to magnetic ferroics and cover a wide spectrum of magnetic domain phenomena. In co...

  17. Optical time-domain mixer

    Science.gov (United States)

    Valley, George C.; Sefler, George A.

    2010-08-01

    We simulate an optical time-domain mixer that can be used to make a photonic analog-to-digital converter (ADC) or a digital demodulator for high-speed optical communications signals. In the basic mixer, a high frequency RF signal modulates a repetitively chirped optical carrier; this RF/optical waveform then is dispersed in one transverse dimension, and imaged onto a 2-dimensional transparency or spatial light modulator whose pixels are modulated with randomly chosen transmission or reflection coefficients (the optical mixing matrix). Following transmission through or reflection from the mixing matrix, the optical waveform from each row of the matrix is recombined and directed to a photodiode and electronics that integrate over the repetition period of the chirped source. Finally, each of these signals is digitized by an independent ADC sampling at a rate equal to the pulse repetition rate of the chirp source. A digital replica of the input RF signal can be recovered by digital signal processing from the digital output of the ADCs and the values of the transmission or reflection coefficients of the mixing matrix. The effective sampling rate is given by the number of pixels per row of the mixing matrix times the repetition rate of the chirp source while the effective resolution is controlled by the resolution of the electronic ADCs and the distortions introduced by the optical mixing process.

  18. Deformation of Entire Functions with Baker Domains

    DEFF Research Database (Denmark)

    Fagella, Nuria; Henriksen, Christian

    2006-01-01

    We consider entire transcendental functions f with an invariant (or periodic) Baker Domain. First, we classify these domains into three types (hyperbolic, simply parabolic and doubly parabolic) according to the surface they induce when we take the quotient by the dynamics. Second, we study the sp...... the space of quasiconformal deformations of an entire map with such a Baker Domain by studying its Teichmuller Space....

  19. Discovering Structure in the Moral Domain

    OpenAIRE

    Chakroff, Aleksandr

    2015-01-01

    Early moral psychologists identified the moral domain with a class of actions that negatively impacted the wellbeing of others or violated their rights. However, anthropological work suggested that this view failed to capture the full extent of the moral domain, which can include victimless actions (e.g., food taboos), especially among socially conservative or non-Western individuals. Which kinds of acts are included in the moral domain? Along which dimensions do the acts differ from one anot...

  20. Heterogeneous Multitask Metric Learning Across Multiple Domains.

    Science.gov (United States)

    Luo, Yong; Wen, Yonggang; Tao, Dacheng

    2017-10-04

    Distance metric learning plays a crucial role in diverse machine learning algorithms and applications. When the labeled information in a target domain is limited, transfer metric learning (TML) helps to learn the metric by leveraging the sufficient information from other related domains. Multitask metric learning (MTML), which can be regarded as a special case of TML, performs transfer across all related domains. Current TML tools usually assume that the same feature representation is exploited for different domains. However, in real-world applications, data may be drawn from heterogeneous domains. Heterogeneous transfer learning approaches can be adopted to remedy this drawback by deriving a metric from the learned transformation across different domains. However, they are often limited in that only two domains can be handled. To appropriately handle multiple domains, we develop a novel heterogeneous MTML (HMTML) framework. In HMTML, the metrics of all different domains are learned together. The transformations derived from the metrics are utilized to induce a common subspace, and the high-order covariance among the predictive structures of these domains is maximized in this subspace. There do exist a few heterogeneous transfer learning approaches that deal with multiple domains, but the high-order statistics (correlation information), which can only be exploited by simultaneously examining all domains, is ignored in these approaches. Compared with them, the proposed HMTML can effectively explore such high-order information, thus obtaining more reliable feature transformations and metrics. Effectiveness of our method is validated by the extensive and intensive experiments on text categorization, scene classification, and social image annotation.

  1. Ferromagnetic stripe domains in ultrathin films

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, B. [Department of Secondary Science and Mathematics Education, University of Mersin, Yenisehir Campus, 33169 Mersin (Turkey)]. E-mail: bengukaplan@yahoo.com

    2005-03-01

    Using simple magnetostatic considerations, we discuss the domain structure and the domain-wall width, {omega}, in ultrathin magnetic films (of a few monolayer thickness) and in an atomic monolayer. The demagnetizing energy is calculated in a continuum theory which is valid provided that the domains are large compared with the lattice spacing. The calculated domain-wall width, {omega}, and the surface anisotropy constant, K{sub s}, are compared with the experimental data for thin epitaxial Co/Au (111) films and a good coincidence is obtained between both results.

  2. Planar domain walls in black hole spacetimes

    Science.gov (United States)

    Ficek, Filip; Mach, Patryk

    2018-02-01

    We investigate the behavior of low-mass, planar domain walls in the so-called ϕ4 model of the scalar field on the Schwarzschild and Kerr backgrounds. We focus on a transit of a domain wall through a black hole and solve numerically the equations of motion for a range of parameters of the domain wall and the black hole. We observe a behavior resembling an occurrence of ringing modes. Perturbations of domain walls vanish during latter evolution, suggesting their stability against a passage through the black hole. The results obtained for Kerr and Reissner-Nordström black holes are also compared.

  3. Sampling in the Linear Canonical Transform Domain

    Directory of Open Access Journals (Sweden)

    Bing-Zhao Li

    2012-01-01

    Full Text Available This paper investigates the interpolation formulae and the sampling theorem for bandpass signals in the linear canonical transform (LCT domain. Firstly, one of the important relationships between the bandpass signals in the Fourier domain and the bandpass signals in the LCT domain is derived. Secondly, two interpolation formulae from uniformly sampled points at half of the sampling rate associated with the bandpass signals and their generalized Hilbert transform or the derivatives in the LCT domain are obtained. Thirdly, the interpolation formulae from nonuniform samples are investigated. The simulation results are also proposed to verify the correctness of the derived results.

  4. Building the DAML Electronic Commerce Domain

    National Research Council Canada - National Science Library

    Anyiwo, David

    2001-01-01

    The project captured additional functional and technical requirements for collaboration and exchange in the electronics industry's value chain, and refined the eCommerce domain ontology requirements...

  5. Multiple graph regularized protein domain ranking

    Directory of Open Access Journals (Sweden)

    Wang Jim

    2012-11-01

    Full Text Available Abstract Background Protein domain ranking is a fundamental task in structural biology. Most protein domain ranking methods rely on the pairwise comparison of protein domains while neglecting the global manifold structure of the protein domain database. Recently, graph regularized ranking that exploits the global structure of the graph defined by the pairwise similarities has been proposed. However, the existing graph regularized ranking methods are very sensitive to the choice of the graph model and parameters, and this remains a difficult problem for most of the protein domain ranking methods. Results To tackle this problem, we have developed the Multiple Graph regularized Ranking algorithm, MultiG-Rank. Instead of using a single graph to regularize the ranking scores, MultiG-Rank approximates the intrinsic manifold of protein domain distribution by combining multiple initial graphs for the regularization. Graph weights are learned with ranking scores jointly and automatically, by alternately minimizing an objective function in an iterative algorithm. Experimental results on a subset of the ASTRAL SCOP protein domain database demonstrate that MultiG-Rank achieves a better ranking performance than single graph regularized ranking methods and pairwise similarity based ranking methods. Conclusion The problem of graph model and parameter selection in graph regularized protein domain ranking can be solved effectively by combining multiple graphs. This aspect of generalization introduces a new frontier in applying multiple graphs to solving protein domain ranking applications.

  6. Multiple graph regularized protein domain ranking

    KAUST Repository

    Wang, Jim Jing-Yan

    2012-11-19

    Background: Protein domain ranking is a fundamental task in structural biology. Most protein domain ranking methods rely on the pairwise comparison of protein domains while neglecting the global manifold structure of the protein domain database. Recently, graph regularized ranking that exploits the global structure of the graph defined by the pairwise similarities has been proposed. However, the existing graph regularized ranking methods are very sensitive to the choice of the graph model and parameters, and this remains a difficult problem for most of the protein domain ranking methods.Results: To tackle this problem, we have developed the Multiple Graph regularized Ranking algorithm, MultiG-Rank. Instead of using a single graph to regularize the ranking scores, MultiG-Rank approximates the intrinsic manifold of protein domain distribution by combining multiple initial graphs for the regularization. Graph weights are learned with ranking scores jointly and automatically, by alternately minimizing an objective function in an iterative algorithm. Experimental results on a subset of the ASTRAL SCOP protein domain database demonstrate that MultiG-Rank achieves a better ranking performance than single graph regularized ranking methods and pairwise similarity based ranking methods.Conclusion: The problem of graph model and parameter selection in graph regularized protein domain ranking can be solved effectively by combining multiple graphs. This aspect of generalization introduces a new frontier in applying multiple graphs to solving protein domain ranking applications. 2012 Wang et al; licensee BioMed Central Ltd.

  7. Trade name and trademark versus domain

    Directory of Open Access Journals (Sweden)

    Jarmila Pokorná

    2013-01-01

    Full Text Available Internet domains have become an integral part of our lives, so one can easily understand that during their use, conflicts can arise, whose participants will search for rules enabling resolution of conflicts. Since the domain name is a replacement of the computer IP address, in the technical sense of the word, this does not concern for domain names a commercial name or brand, because it primarily does not belong to a person in the legal sense of the word and does not serve for its individualization. The average user regularly affiliates domain names with a person offering goods or services on the relevant Website. Domain names used by entrepreneurs in their business activity are often chosen so that the second-level domain (SLD would use words that form the trade name of corporations formed of trading companies. This fact brings domain names close to such designations that serve the individualization of persons or products, especially the trademarks and the commercial name. Domains can come into conflict with the rights to designations, especially trademarks and commercial names. Court practice is resolving these conflicts using rules for unfair competition, or rules for protection of commercial names and trademarks, but it is not ruled out that in the future, special legal regulation of domain names could be established.

  8. Maritime Domain Awareness Architecture Management Hub Strategy

    National Research Council Canada - National Science Library

    2008-01-01

    This document provides an initial high level strategy for carrying out the responsibilities of the national Maritime Domain Awareness Architecture Management Hub to deliver a standards based service...

  9. Transform domain steganography with blind source separation

    Science.gov (United States)

    Jouny, Ismail

    2015-05-01

    This paper applies blind source separation or independent component analysis for images that may contain mixtures of text, audio, or other images for steganography purposes. The paper focuses on separating mixtures in the transform domain such as Fourier domain or the Wavelet domain. The study addresses the effectiveness of steganography when using linear mixtures of multimedia components and the ability of standard blind sources separation techniques to discern hidden multimedia messages. Mixing in the space, frequency, and wavelet (scale) domains is compared. Effectiveness is measured using mean square error rate between original and recovered images.

  10. Public domain optical character recognition

    Science.gov (United States)

    Garris, Michael D.; Blue, James L.; Candela, Gerald T.; Dimmick, Darrin L.; Geist, Jon C.; Grother, Patrick J.; Janet, Stanley A.; Wilson, Charles L.

    1995-03-01

    A public domain document processing system has been developed by the National Institute of Standards and Technology (NIST). The system is a standard reference form-based handprint recognition system for evaluating optical character recognition (OCR), and it is intended to provide a baseline of performance on an open application. The system's source code, training data, performance assessment tools, and type of forms processed are all publicly available. The system recognizes the handprint entered on handwriting sample forms like the ones distributed with NIST Special Database 1. From these forms, the system reads hand-printed numeric fields, upper and lowercase alphabetic fields, and unconstrained text paragraphs comprised of words from a limited-size dictionary. The modular design of the system makes it useful for component evaluation and comparison, training and testing set validation, and multiple system voting schemes. The system contains a number of significant contributions to OCR technology, including an optimized probabilistic neural network (PNN) classifier that operates a factor of 20 times faster than traditional software implementations of the algorithm. The source code for the recognition system is written in C and is organized into 11 libraries. In all, there are approximately 19,000 lines of code supporting more than 550 subroutines. Source code is provided for form registration, form removal, field isolation, field segmentation, character normalization, feature extraction, character classification, and dictionary-based postprocessing. The recognition system has been successfully compiled and tested on a host of UNIX workstations. This paper gives an overview of the recognition system's software architecture, including descriptions of the various system components along with timing and accuracy statistics.

  11. Molecular dynamics study of ferroelectric domain nucleation and domain switching dynamics.

    Science.gov (United States)

    Boddu, Vishal; Endres, Florian; Steinmann, Paul

    2017-04-11

    Ferroelectric materials contain domains of ordered electric dipoles, separated by domain walls, that can undergo polarisation switching under externally applied electric fields. The domain switching dynamics in ferroelectric materials plays an essential role in their application to electronic and electro-optic de- vices. Previous studies suggest that the switching occurs largely through domain wall motion which is explained from the viewpoint of statistical physics on surface growth as the behaviour of a pinned elas- tic interface. We perform molecular dynamics simulations to investigate the domain switching process and quantitatively estimate the switching speed of anti-parallel 180° domains in ferroelectric, tetragonal BaTiO 3 perfect single crystals at room temperature using the core-shell model. We observe an unprece- dented, non-linear increase in the domain switching speed caused by the nucleation of new domains within the switching domain. We determine the strength of the electric field to evoke nucleation of new domains and show that the nucleated domains diffuse into nearby favourable domains when the electric field is removed. Furthermore, we discuss the prominence of domain nucleations during ferroelectric switching.

  12. Genomewide analysis of LATERAL ORGAN BOUNDARIES Domain ...

    Indian Academy of Sciences (India)

    The investigation of transcription factor (TF) families is a major focus of postgenomic research. The plant-specific ASYMMETRIC LEAVES2-LIKE (ASL) / LATERAL ORGAN BOUNDARIES Domain (LBD) proteins constitute a major zincfinger-like-domain transcription factor family, and regulate diverse biological processes in ...

  13. Domain decomposition methods for hyperbolic problems

    Indian Academy of Sciences (India)

    problems using domain decomposition but this technique faces difficulties if the system becomes characteristic at the inter-element boundaries. By making the inter-element boundaries move faster than the fastest wave speed associated with the hyperbolic system we are able to overcome this problem. Keywords. Domain ...

  14. Enhanced functional and structural domain assignments using ...

    Indian Academy of Sciences (India)

    Unknown

    biology of MTB, yet the functions of many MTB proteins are unknown. We have used sensitive profile-based search procedures to assign functional and structural domains to infer functions of gene products encoded in. MTB. These domain assignments have been made using a compendium of sequence and structural ...

  15. Time domain NMR applied to food products

    NARCIS (Netherlands)

    Duynhoven, van J.P.M.; Voda, A.; Witek, M.M.; As, van H.

    2010-01-01

    Time-domain NMR is being used throughout all areas of food science and technology. A wide range of one- and two-dimensional relaxometric and diffusometric applications have been implemented on cost-effective, robust and easy-to-use benchtop NMR equipment. Time-domain NMR applications do not only

  16. Domain Wall Propagation through Spin Wave Emission

    NARCIS (Netherlands)

    Wang, X.S.; Yan, P.; Shen, Y.H.; Bauer, G.E.W.; Wang, X.R.

    2012-01-01

    We theoretically study field-induced domain wall motion in an electrically insulating ferromagnet with hard- and easy-axis anisotropies. Domain walls can propagate along a dissipationless wire through spin wave emission locked into the known soliton velocity at low fields. In the presence of

  17. Strong diamagnetism for general domains and applications

    DEFF Research Database (Denmark)

    Fournais, Søren; Helffer, Bernard

    2007-01-01

    We consider the Neumann Laplacian with constant magnetic field on a regular domain. Let $B$ be the strength of the magnetic field, and let $\\lambda_1(B)$ be the first eigenvalue of the magnetic Neumann Laplacian on the domain. It is proved that $B \\mapsto \\lambda_1(B)$ is monotone increasing for ...

  18. Thermodynamic magnon recoil for domain wall motion

    NARCIS (Netherlands)

    Yan, P.; Cao, Y.; Sinova, J.

    2015-01-01

    We predict a thermodynamic magnon recoil effect for domain wall motions in the presence of temperature gradients. All current thermodynamic theories assert that a magnetic domain wall must move toward the hotter side, based on equilibrium thermodynamic arguments. Microscopic calculations, on the

  19. UBA domain containing proteins in fission yeast

    DEFF Research Database (Denmark)

    Hartmann-Petersen, Rasmus; Semple, Colin A M; Ponting, Chris P

    2003-01-01

    characterised on both the functional and structural levels. One example of a widespread ubiquitin binding module is the ubiquitin associated (UBA) domain. Here, we discuss the approximately 15 UBA domain containing proteins encoded in the relatively small genome of the fission yeast Schizosaccharomyces pombe...

  20. Domain 2: Sport Safety and Injury Prevention

    Science.gov (United States)

    Gurchiek, Larry; Mokha, Monique Butcher

    2004-01-01

    Most coaches recognize the importance of creating a safe environment and preventing injuries of their athletes. Domain 2 is dedicated to this important aspect of coaching, and outlines specific areas within safety and injury prevention that coaches should address. Domain 2 sets the standards for facility, equipment, and environmental safety…

  1. Superfast domain walls in KTP single crystals

    Science.gov (United States)

    Shur, V. Ya.; Esin, A. A.; Alam, M. A.; Akhmatkhanov, A. R.

    2017-10-01

    Potassium titanyl phosphate KTiOPO4 (KTP) crystals with periodical ferroelectric domain structures are one of the most promising materials for nonlinear optics, in which the main types of nonlinear optical interactions have been demonstrated. Despite the crucial importance of the in situ visualization of domain structure kinetics for creation of high quality periodical domain gratings, there are only a few works concerning KTP. We present the results of in situ visualization of domain kinetics in KTP with the time resolution down to 12.5 μs and simultaneous recording of the switching current data. The wide range of wall velocities with two orders of magnitude difference was observed for switching in a uniform electric field. The kinetic maps allowed analyzing the spatial distribution of wall motion velocities and classifying the walls by velocity ranges. The distinguished slow, fast, and superfast types of domain walls differed by their orientation. It was shown that the fast and slow domain walls provided the smooth input to the switching current, whereas the short-lived superfast walls resulted in short current peaks. The mobility and the threshold fields for all types of domain walls were estimated. The revealed increase in the wall velocity with deviation from low-index crystallographic planes for slow and fast walls was considered in terms of determined step generation and anisotropic kink motion. The obtained results are important for further development of domain engineering in KTP required for creation of high power, reliable, and effective coherent light sources.

  2. Chiral gauge theories with domain wall fermions

    OpenAIRE

    Golterman, M.; Jansen, K.; Petcher, D.; Vink, J.

    1993-01-01

    We have investigated a proposal to construct chiral gauge theories on the lattice using domain wall fermions. The model contains two opposite chirality zeromodes, which live on two domain walls. We couple only one of them to a gauge field, but find that mirror fermions which also couple to the gauge field always seem to exist.

  3. Is the myonuclear domain size fixed?

    NARCIS (Netherlands)

    van der Meer, S.F.T.; Jaspers, R. T.; Degens, H.

    2011-01-01

    It has been suggested that the number of myonuclei in a muscle fibre changes in proportion to the change in fibre size, resulting in a constant myonuclear domain size, defined as the cytoplasmic volume per myonucleus. The myonuclear domain size varies, however, between fibre types and is inversely

  4. Frequency Domain Image Filtering Using CUDA

    Directory of Open Access Journals (Sweden)

    Muhammad Awais Rajput

    2014-10-01

    Full Text Available In this paper, we investigate the implementation of image filtering in frequency domain using NVIDIA?s CUDA (Compute Unified Device Architecture. In contrast to signal and image filtering in spatial domain which uses convolution operations and hence is more compute-intensive for filters having larger spatial extent, the frequency domain filtering uses FFT (Fast Fourier Transform which is much faster and significantly reduces the computational complexity of the filtering. We implement the frequency domain filtering on CPU and GPU respectively and analyze the speed-up obtained from the CUDA?s parallel processing paradigm. In order to demonstrate the efficiency of frequency domain filtering on CUDA, we implement three frequency domain filters, i.e., Butterworth, low-pass and Gaussian for processing different sizes of images on CPU and GPU respectively and perform the GPU vs. CPU benchmarks. The results presented in this paper show that the frequency domain filtering with CUDA achieves significant speed-up over the CPU processing in frequency domain with the same level of (output image quality on both the processing architectures

  5. implementation of spatial domain homomorphic filtering

    African Journals Online (AJOL)

    eobe

    Keywords: Spatial domain homomorphic filtering, contrast enhancement, image processing, java programming. 1. INTRODUCTION. There is a lot of background literature on frequency- domain Homomorphic filtering [1-2]. However, such a scheme is too costly and complex to implement in digital and embedded hardware ...

  6. Time Domain Stability Margin Assessment Method

    Science.gov (United States)

    Clements, Keith

    2017-01-01

    The baseline stability margins for NASA's Space Launch System (SLS) launch vehicle were generated via the classical approach of linearizing the system equations of motion and determining the gain and phase margins from the resulting frequency domain model. To improve the fidelity of the classical methods, the linear frequency domain approach can be extended by replacing static, memoryless nonlinearities with describing functions. This technique, however, does not address the time varying nature of the dynamics of a launch vehicle in flight. An alternative technique for the evaluation of the stability of the nonlinear launch vehicle dynamics along its trajectory is to incrementally adjust the gain and/or time delay in the time domain simulation until the system exhibits unstable behavior. This technique has the added benefit of providing a direct comparison between the time domain and frequency domain tools in support of simulation validation.

  7. The Private Legal Governance of Domain Names

    DEFF Research Database (Denmark)

    Schovsbo, Jens Hemmingsen

    2016-01-01

    This chapter evaluates the performance of the special private tribunals or panels such as the UDRP which have been developed within complicated systems of self- and co-regulation such as ICANN to decide disputes over domain names. It uses two different dispute resolution models viz. the UDRP (WIPO......) and the Danish Complaints Board for Internet Domain Names (the Board) to discuss how and to what extent the domain name system balances interests between trademark owners and other users of domain names and secures the rule of law (legal certainty and predictability) with a special focus on cases where...... trademarks are used as (parts of) domain names to express criticism of the trademark holder or the trademark itself (e.g. “TMsucks.com” / “lorteTM.dk”)....

  8. Requirements analysis, domain knowledge, and design

    Science.gov (United States)

    Potts, Colin

    1988-01-01

    Two improvements to current requirements analysis practices are suggested: domain modeling, and the systematic application of analysis heuristics. Domain modeling is the representation of relevant application knowledge prior to requirements specification. Artificial intelligence techniques may eventually be applicable for domain modeling. In the short term, however, restricted domain modeling techniques, such as that in JSD, will still be of practical benefit. Analysis heuristics are standard patterns of reasoning about the requirements. They usually generate questions of clarification or issues relating to completeness. Analysis heuristics can be represented and therefore systematically applied in an issue-based framework. This is illustrated by an issue-based analysis of JSD's domain modeling and functional specification heuristics. They are discussed in the context of the preliminary design of simple embedded systems.

  9. Contribution of the CR domain to P-selectin lectin domain allostery by regulating the orientation of the EGF domain.

    Directory of Open Access Journals (Sweden)

    Shouqin Lü

    Full Text Available The allostery of P-selectin has been studied extensively with a focus on the Lec and EGF domains, whereas the contribution of the CR domain remains unclear. Here, molecular dynamics simulations (MDS combined with homology modeling were preformed to investigate the impact of the CR domain on P-selectin allostery. The results indicated that the CR domain plays a role in the allosteric dynamics of P-selectin in two ways. First, the CR1 domain tends to stabilize the low affinity of P-selectin during the equilibration processes with the transition inhibition from the S1 to S1' state by restraining the extension of the bent EGF orientation, or with the relaxation acceleration of the S2 state by promoting the bending of the extended EGF orientation. Second, the existence of CR domain increases intramolecular extension prior to complex separation, increasing the time available for the allosteric shift during forced dissociation with a prolonged bond duration. These findings further our understanding of the structure-function relationship of P-selectin with the enriched micro-structural bases of the CR domain.

  10. Interoperable domain models: the ISO land administration domain model LADM and its external classes

    CSIR Research Space (South Africa)

    Lemmen, CHJ

    2011-09-01

    Full Text Available This paper provides a brief overview of one of the first spatial domain standards: a standard for the domain of Land Administration (LA). This standard is in the draft stage of development now (May 2011). The development of domain standards is a...

  11. Time-domain modeling of electromagnetic diffusion with a frequency-domain code

    NARCIS (Netherlands)

    Mulder, W.A.; Wirianto, M.; Slob, E.C.

    2007-01-01

    We modeled time-domain EM measurements of induction currents for marine and land applications with a frequency-domain code. An analysis of the computational complexity of a number of numerical methods shows that frequency-domain modeling followed by a Fourier transform is an attractive choice if a

  12. Local coexpression domains in the genome of rice show no microsynteny with Arabidopsis domains

    NARCIS (Netherlands)

    Ren, X.Y.; Stiekema, W.J.; Nap, J.P.H.

    2007-01-01

    Chromosomal coexpression domains are found in a number of different genomes under various developmental conditions. The size of these domains and the number of genes they contain vary. Here, we define local coexpression domains as adjacent genes where all possible pair-wise correlations of

  13. Architecture for Mobile Heterogeneous Multi Domain Networks

    Directory of Open Access Journals (Sweden)

    Arjan Durresi

    2010-01-01

    Full Text Available Multi domain networks can be used in several scenarios including military, enterprize networks, emergency networks and many other cases. In such networks, each domain might be under its own administration. Therefore, the cooperation among domains is conditioned by individual domain policies regarding sharing information, such as network topology, connectivity, mobility, security, various service availability and so on. We propose a new architecture for Heterogeneous Multi Domain (HMD networks, in which one the operations are subject to specific domain policies. We propose a hierarchical architecture, with an infrastructure of gateways at highest-control level that enables policy based interconnection, mobility and other services among domains. Gateways are responsible for translation among different communication protocols, including routing, signalling, and security. Besides the architecture, we discuss in more details the mobility and adaptive capacity of services in HMD. We discuss the HMD scalability and other advantages compared to existing architectural and mobility solutions. Furthermore, we analyze the dynamic availability at the control level of the hierarchy.

  14. Evolution of domain promiscuity in eukaryotic genomes—a perspective from the inferred ancestral domain architectures†

    Science.gov (United States)

    Cohen-Gihon, Inbar; Fong, Jessica H.; Sharan, Roded; Nussinov, Ruth

    2012-01-01

    Most eukaryotic proteins are composed of two or more domains. These assemble in a modular manner to create new proteins usually by the acquisition of one or more domains to an existing protein. Promiscuous domains which are found embedded in a variety of proteins and co-exist with many other domains are of particular interest and were shown to have roles in signaling pathways and mediating network communication. The evolution of domain promiscuity is still an open problem, mostly due to the lack of sequenced ancestral genomes. Here we use inferred domain architectures of ancestral genomes to trace the evolution of domain promiscuity in eukaryotic genomes. We find an increase in average promiscuity along many branches of the eukaryotic tree. Moreover, domain promiscuity can proceed at almost a steady rate over long evolutionary time or exhibit lineage-specific acceleration. We also observe that many signaling and regulatory domains gained domain promiscuity around the Bilateria divergence. In addition we show that those domains that played a role in the creation of two body axes and existed before the divergence of the bilaterians from fungi/metazoan achieve a boost in their promiscuities during the bilaterian evolution. PMID:21127809

  15. Evolution of domain promiscuity in eukaryotic genomes--a perspective from the inferred ancestral domain architectures.

    Science.gov (United States)

    Cohen-Gihon, Inbar; Fong, Jessica H; Sharan, Roded; Nussinov, Ruth; Przytycka, Teresa M; Panchenko, Anna R

    2011-03-01

    Most eukaryotic proteins are composed of two or more domains. These assemble in a modular manner to create new proteins usually by the acquisition of one or more domains to an existing protein. Promiscuous domains which are found embedded in a variety of proteins and co-exist with many other domains are of particular interest and were shown to have roles in signaling pathways and mediating network communication. The evolution of domain promiscuity is still an open problem, mostly due to the lack of sequenced ancestral genomes. Here we use inferred domain architectures of ancestral genomes to trace the evolution of domain promiscuity in eukaryotic genomes. We find an increase in average promiscuity along many branches of the eukaryotic tree. Moreover, domain promiscuity can proceed at almost a steady rate over long evolutionary time or exhibit lineage-specific acceleration. We also observe that many signaling and regulatory domains gained domain promiscuity around the Bilateria divergence. In addition we show that those domains that played a role in the creation of two body axes and existed before the divergence of the bilaterians from fungi/metazoan achieve a boost in their promiscuities during the bilaterian evolution.

  16. A new principle technic for the transformation from frequency domain to time domain

    Science.gov (United States)

    Gao, Ben-Qing

    2017-03-01

    A principle technic for the transformation from frequency domain to time domain is presented. Firstly, a special type of frequency domain transcendental equation is obtained for an expected frequency domain parameter which is a rational or irrational fraction expression. Secondly, the inverse Laplace transformation is performed. When the two time-domain factors corresponding to the two frequency domain factors at two sides of frequency domain transcendental equation are known quantities, a time domain transcendental equation is reached. At last, the expected time domain parameter corresponding to the expected frequency domain parameter can be solved by the inverse convolution process. Proceeding from rational or irrational fraction expression, all solving process is provided. In the meantime, the property of time domain sequence is analyzed and the strategy for choosing the parameter values is described. Numerical examples are presented to verify the proposed theory and technic. Except for rational or irrational fraction expressions, examples of complex relative permittivity of water and plasma are used as verification method. The principle method proposed in the paper can easily solve problems which are difficult to be solved by Laplace transformation.

  17. Surface magnetostatic oscillations in elliptical bubble domains

    Science.gov (United States)

    Popov, M. A.; Zavislyak, I. V.

    2009-01-01

    A theory of surface magnetostatic oscillations in magnetic bubble domains with an elliptical cross section is presented. The dependences of the eigenfrequencies of resonant modes on the applied magnetic field are analyzed for a barium hexaferrite sample with allowance made for the change in the domain size due to a variation in the bias magnetic field. The range of frequency tuning in response to a magnetic field ranging from the elliptical instability field to the collapse field is estimated. It is demonstrated that elliptical bubble domains can be used as microminiature resonators operating in the millimeter range.

  18. Domain landscapes of somatic mutations in cancer.

    Science.gov (United States)

    Nehrt, Nathan L; Peterson, Thomas A; Park, DoHwan; Kann, Maricel G

    2012-06-18

    Large-scale tumor sequencing projects are now underway to identify genetic mutations that drive tumor initiation and development. Most studies take a gene-based approach to identifying driver mutations, highlighting genes mutated in a large percentage of tumor samples as those likely to contain driver mutations. However, this gene-based approach usually does not consider the position of the mutation within the gene or the functional context the position of the mutation provides. Here we introduce a novel method for mapping mutations to distinct protein domains, not just individual genes, in which they occur, thus providing the functional context for how the mutation contributes to disease. Furthermore, aggregating mutations from all genes containing a specific protein domain enables the identification of mutations that are rare at the gene level, but that occur frequently within the specified domain. These highly mutated domains potentially reveal disruptions of protein function necessary for cancer development. We mapped somatic mutations from the protein coding regions of 100 colon adenocarcinoma tumor samples to the genes and protein domains in which they occurred, and constructed topographical maps to depict the "mutational landscapes" of gene and domain mutation frequencies. We found significant mutation frequency in a number of genes previously known to be somatically mutated in colon cancer patients including APC, TP53 and KRAS. In addition, we found significant mutation frequency within specific domains located in these genes, as well as within other domains contained in genes having low mutation frequencies. These domain "peaks" were enriched with functions important to cancer development including kinase activity, DNA binding and repair, and signal transduction. Using our method to create the domain landscapes of mutations in colon cancer, we were able to identify somatic mutations with high potential to drive cancer development. Interestingly, the

  19. Two-Domain DNA Strand Displacement

    Directory of Open Access Journals (Sweden)

    Luca Cardelli

    2010-06-01

    Full Text Available We investigate the computing power of a restricted class of DNA strand displacement structures: those that are made of double strands with nicks (interruptions in the top strand. To preserve this structural invariant, we impose restrictions on the single strands they interact with: we consider only two-domain single strands consisting of one toehold domain and one recognition domain. We study fork and join signal-processing gates based on these structures, and we show that these systems are amenable to formalization and to mechanical verification.

  20. Shape design sensitivity analysis using domain information

    Science.gov (United States)

    Seong, Hwal-Gyeong; Choi, Kyung K.

    1985-01-01

    A numerical method for obtaining accurate shape design sensitivity information for built-up structures is developed and demonstrated through analysis of examples. The basic character of the finite element method, which gives more accurate domain information than boundary information, is utilized for shape design sensitivity improvement. A domain approach for shape design sensitivity analysis of built-up structures is derived using the material derivative idea of structural mechanics and the adjoint variable method of design sensitivity analysis. Velocity elements and B-spline curves are introduced to alleviate difficulties in generating domain velocity fields. The regularity requirements of the design velocity field are studied.

  1. Domain Specific Language Support for Exascale

    Energy Technology Data Exchange (ETDEWEB)

    Sadayappan, Ponnuswamy [The Ohio State Univ., Columbus, OH (United States)

    2017-02-24

    Domain-Specific Languages (DSLs) offer an attractive path to Exascale software since they provide expressive power through appropriate abstractions and enable domain-specific optimizations. But the advantages of a DSL compete with the difficulties of implementing a DSL, even for a narrowly defined domain. The DTEC project addresses how a variety of DSLs can be easily implemented to leverage existing compiler analysis and transformation capabilities within the ROSE open source compiler as part of a research program focusing on Exascale challenges. The OSU contributions to the DTEC project are in the area of code generation from high-level DSL descriptions, as well as verification of the automatically-generated code.

  2. System Identification A Frequency Domain Approach

    CERN Document Server

    Pintelon, Rik

    2012-01-01

    System identification is a general term used to describe mathematical tools and algorithms that build dynamical models from measured data. Used for prediction, control, physical interpretation, and the designing of any electrical systems, they are vital in the fields of electrical, mechanical, civil, and chemical engineering. Focusing mainly on frequency domain techniques, System Identification: A Frequency Domain Approach, Second Edition also studies in detail the similarities and differences with the classical time domain approach. It high??lights many of the important steps in the identi

  3. Cross domains Arabic named entity recognition system

    Science.gov (United States)

    Al-Ahmari, S. Saad; Abdullatif Al-Johar, B.

    2016-07-01

    Named Entity Recognition (NER) plays an important role in many Natural Language Processing (NLP) applications such as; Information Extraction (IE), Question Answering (QA), Text Clustering, Text Summarization and Word Sense Disambiguation. This paper presents the development and implementation of domain independent system to recognize three types of Arabic named entities. The system works based on a set of domain independent grammar-rules along with Arabic part of speech tagger in addition to gazetteers and lists of trigger words. The experimental results shown, that the system performed as good as other systems with better results in some cases of cross-domains corpora.

  4. Targeted delivery to cartilage is critical for in vivo efficacy of insulin-like growth factor 1 in a rat model of osteoarthritis.

    Science.gov (United States)

    Loffredo, Francesco S; Pancoast, James R; Cai, Lei; Vannelli, Todd; Dong, Jesse Z; Lee, Richard T; Patwari, Parth

    2014-05-01

    Acute articular injuries lead to an increased risk of progressive joint damage and osteoarthritis (OA), and no therapies are currently available to repair or protect the injured joint tissue. Intraarticular delivery of therapeutic proteins has been limited by their rapid clearance from the joint space and lack of retention within cartilage. The aim of this study was to test whether targeted delivery to cartilage by fusion with a heparin-binding domain would be sufficient to prolong the in vivo function of the insulin-like growth factor 1 (IGF-1). We produced a humanized and optimized recombinant HB-IGF-1 fusion protein. By injecting HB-IGF-1, IGF-1, or saline alone into the knee joints of adult Lewis rats, we tested whether fusion with a heparin-binding domain 1) altered the kinetics of retention in joint tissues, 2) prolonged functional stimulation as measured by radiolabel incorporation, and 3) enhanced efficacy in a rat model of surgically induced OA, using weekly injections. Fusion of heparin-binding domain with IGF-1 prolonged retention in articular and meniscal cartilage from <1 day to 8 days after injection. Unmodified IGF-1 had no functional effect 2 days after injection, whereas HB-IGF-1 stimulated meniscal cartilage at least 4 days after injection. HB-IGF-1, but not IGF-1, significantly slowed cartilage damage in a rat model of OA. Heparin-binding domain fusions can transform rapidly cleared proteins into potential intraarticular therapies by targeting them to cartilage. Copyright © 2014 by the American College of Rheumatology.

  5. Climiate Resilience Screening Index and Domain Scores

    Data.gov (United States)

    U.S. Environmental Protection Agency — CRSI and related-domain scores for all 50 states and 3135 counties in the U.S. This dataset is not publicly accessible because: They are already available within the...

  6. Maritime Domain Awareness: A Western Hemisphere Imperative

    National Research Council Canada - National Science Library

    Minta, James L

    2006-01-01

    .... The focus of this project is to research a question posed by U.S. Northern Command concerning whether Canada and the United States should enter into a bi-national agreement for maritime domain awareness...

  7. Magnified time-domain ghost imaging

    Science.gov (United States)

    Ryczkowski, Piotr; Barbier, Margaux; Friberg, Ari T.; Dudley, John M.; Genty, Goëry

    2017-04-01

    Ghost imaging allows the imaging of an object without directly seeing this object. Originally demonstrated in the spatial domain, it was recently shown that ghost imaging can be transposed into the time domain to detect ultrafast signals, even in the presence of distortion. We propose and experimentally demonstrate a temporal ghost imaging scheme which generates a 5× magnified ghost image of an ultrafast waveform. Inspired by shadow imaging in the spatial domain and building on the dispersive Fourier transform of an incoherent supercontinuum in an optical fiber, the approach overcomes the resolution limit of standard time-domain ghost imaging generally imposed by the detectors speed. The method can be scaled up to higher magnification factors using longer fiber lengths and light source with shorter duration.

  8. Patient Centric Ontology for Telehealth Domain

    DEFF Research Database (Denmark)

    Jørgensen, Daniel Bjerring; Hallenborg, Kasper; Demazeau, Yves

    2015-01-01

    This paper presents an ontology for the telehealth domain, a domain that concerns the use of telecommunication to support and deliver health related services e.g. patient monitoring and rehabilitative training. Our vision for the future of telehealth solutions is that they adapt their behavior...... to the needs, habits, and personality of the patient through user modeling and context awareness. The ontology will be our foundation for user modeling of patients in the telehealth domain, and hence it is one of the initial steps toward our vision. Compared to other ontologies within the domain, ours has...... explicit focus on: 1) personality traits of the patient, which is vital for fulfillment of our vision in term of adaptability, and 2) use of international standards to describe diseases, func-tioning and physiological measurement – ICD, ICF and SNOMED respectively – to promote interoperability...

  9. Domain-Specific Modelling Languages in Bigraphs

    DEFF Research Database (Denmark)

    Perrone, Gian David

    Modelling is a ubiquitous activity in human endeavours, and the construction of informatic models of many kinds is the key to understanding and managing the complexity of an increasingly computational world. We advocate the use of domain-specic modelling languages, instantiated within a \\tower......" of models, in order to improve the utility of the models we build, and to ease the process of model construction by moving the languages we use to express such models closer to their respective domains. This thesis is concerned with the study of bigraphical reactive systems as a host for domain...... for deciding reaction rule causation. Finally, we provide a mechanism for the modular construction of domain-specic modelling languages as bigraphical reactive systems, exploring the relationship between vertical renement and language specialisation in this setting. The thesis is composed of several...

  10. Domain walls and spacetime-filling branes

    NARCIS (Netherlands)

    Bergshoeff, E; Wess, J; Ivanov, EA

    1999-01-01

    We discuss branes with one transversal direction (domain walls) and no transversal direction (spacetime-filling branes). In particular, we briefly discuss a relationship between spacetime-filling branes and superstring theories with sixteen supercharges.

  11. Chromatin epigenomic domain folding: size matters

    Directory of Open Access Journals (Sweden)

    Bertrand R. Caré

    2015-09-01

    Full Text Available In eukaryotes, chromatin is coated with epigenetic marks which induce differential gene expression profiles and eventually lead to different cellular phenotypes. One of the challenges of contemporary cell biology is to relate the wealth of epigenomic data with the observed physical properties of chromatin. In this study, we present a polymer physics framework that takes into account the sizes of epigenomic domains. We build a model of chromatin as a block copolymer made of domains with various sizes. This model produces a rich set of conformations which is well explained by finite-size scaling analysis of the coil-globule transition of epigenomic domains. Our results suggest that size-dependent folding of epigenomic domains may be a crucial physical mechanism able to provide chromatin with tissue-specific folding states, these being associated with differential gene expression.

  12. Inter-domain incentives and Internet architecture

    OpenAIRE

    Rajahalme, Jarno

    2012-01-01

    Recent experience in networking research has shown protocol and architecture deployment to be problematic, to say the least. We argue that the typically non-uniform distribution of costs and benefits inherent in many inter-domain designs is a roadblock on the path of deployment that is extremely hard, or costly, to circumvent after the fact. Therefore, the voluntary inter-domain structure that has evolved along with the transition to the commercial Internet of today should be consciously embr...

  13. Cross-Domain Network Fault Localization

    Science.gov (United States)

    2009-06-01

    traffic flow between Autonomous Systems [14]. Links between domains are common points of congestion , and traffic engineering between domains is often...to identify routing faults and congestion [9]. However, implementing network tomography on a large scale faces significant computational challenges [7...14] N. Feamster, J. Borkenhagen, and J. Rexford. Guidelines for interdomain traffic engineering. ACM SIGCOMM Computer Communication Review, 33(5):19

  14. Targeting Discoidin Domain Receptors in Prostate Cancer

    Science.gov (United States)

    2017-08-01

    AWARD NUMBER: W81XWH-15-1-0226 TITLE: Targeting Discoidin Domain Receptors in Prostate Cancer PRINCIPAL INVESTIGATOR: Dr. Rafael Fridman...AND SUBTITLE 5a. CONTRACT NUMBER Targeting Discoidin Domain Receptors in Prostate Cancer 5b. GRANT NUMBER W81XWH-15-1-0226 5c. PROGRAM ELEMENT...response to collagen in prostate cancer . The project’s goal is to define the expression and therapeutic potential of DDRs in prostate cancer . During

  15. Quantum stochastic calculus with maximal operator domains

    OpenAIRE

    Lindsay, J. Martin; Attal, Stéphane

    2004-01-01

    Quantum stochastic calculus is extended in a new formulation in which its stochastic integrals achieve their natural and maximal domains. Operator adaptedness, conditional expectations and stochastic integrals are all defined simply in terms of the orthogonal projections of the time filtration of Fock space, together with sections of the adapted gradient operator. Free from exponential vector domains, our stochastic integrals may be satisfactorily composed yielding quantum Itô formulas for op...

  16. Small Thermal Fluctuations on a Large Domain

    Science.gov (United States)

    Shiromizu, T.; Morikawa, M.

    1996-07-01

    Weak first-order phase transitions proceed with percolation of a new phase. The kinematics of this process is clarified from the point of view of subcritical bubbles. We exdamine the effect of small subcritical bubbles around a large domain of an asymmetric phase by introducing an effective geometry. The percolation process can be understood as a perpetual growth of the large domain aided by the small subcritical bubbles.

  17. Domain knowledge patterns in pedagogical diagnostics

    Science.gov (United States)

    Miarka, Rostislav

    2017-07-01

    This paper shows a proposal of representation of knowledge patterns in RDF(S) language. Knowledge patterns are used for reuse of knowledge. They can be divided into two groups - Top-level knowledge patterns and Domain knowledge patterns. Pedagogical diagnostics is aimed at testing of knowledge of students at primary and secondary school. An example of domain knowledge pattern from pedagogical diagnostics is part of this paper.

  18. Evading the cosmological domain wall problem

    OpenAIRE

    Larsson, Sebastian E.; Sarkar, Subir; White, Peter L.

    1996-01-01

    Discrete symmetries are commonplace in field theoretical models but pose a severe problem for cosmology since they lead to the formation of domain walls during spontaneous symmetry breaking in the early universe. However if one of the vacuua is favoured over the others, either energetically, or because of initial conditions, it will eventually come to dominate the universe. Using numerical methods, we study the evolution of the domain wall network for a variety of field configurations in two ...

  19. Generalized Frequency Domain LMS Adaptive Filter

    Directory of Open Access Journals (Sweden)

    F. Dohnal

    1995-06-01

    Full Text Available The most significant problems of acoustic echo canceller (AEC realizations are high computational complexity and insufficient convergence rate of the applied adaptive algorithms. From the analysis of the frequency domain block adaptive filter [2,3] realization and the modified subband acoustic echo canceller [6] the generalized frequency domain adaptive filter [8,9] has been derived. The result of simulations is demonstrated the efficiency of this algorithm for a stationary noise and real speech signal excitation.

  20. Domain Specific Languages for Interactive Web Services

    DEFF Research Database (Denmark)

    Brabrand, Claus

    This dissertation shows how domain specific languages may be applied to the domain of interactive Web services to obtain flexible, safe, and efficient solutions. We show how each of four key aspects of interactive Web services involving sessions, dynamic creation of HTML/XML documents, form field......, , that supports virtually all aspects of the development of interactive Web services and provides flexible, safe, and efficient solutions....

  1. Robust Named Entity Recognition in Idiosyncratic Domains

    OpenAIRE

    Arnold, Sebastian; Gers, Felix A.; Kilias, Torsten; Löser, Alexander

    2016-01-01

    Named entity recognition often fails in idiosyncratic domains. That causes a problem for depending tasks, such as entity linking and relation extraction. We propose a generic and robust approach for high-recall named entity recognition. Our approach is easy to train and offers strong generalization over diverse domain-specific language, such as news documents (e.g. Reuters) or biomedical text (e.g. Medline). Our approach is based on deep contextual sequence learning and utilizes stacked bidir...

  2. C3 Domain Analysis, Lessons Learned

    Science.gov (United States)

    1993-09-30

    Software Engineering Institute’s (SEI) Feature-Oriented Domain Analysis ( FODA ) [Cohen, et al., 19901 method were the original two methods used to analyze the...oriented methods traditionally used for systems analysis and design. Since these two domain analysis tasks are of a more recent vintage than RLPM and FODA ...object-oriented analysis method), and the FODA method do make the distinction between descriptive and prescriptive phases. Based on our examination of

  3. Between-domain relations of students' academic emotions and their judgments of school domain similarity

    Science.gov (United States)

    Goetz, Thomas; Haag, Ludwig; Lipnevich, Anastasiya A.; Keller, Melanie M.; Frenzel, Anne C.; Collier, Antonie P. M.

    2014-01-01

    With the aim to deepen our understanding of the between-domain relations of academic emotions, a series of three studies was conducted. We theorized that between-domain relations of trait (i.e., habitual) emotions reflected students' judgments of domain similarities, whereas between-domain relations of state (i.e., momentary) emotions did not. This supposition was based on the accessibility model of emotional self-report, according to which individuals' beliefs tend to strongly impact trait, but not state emotions. The aim of Study 1 (interviews; N = 40; 8th and 11th graders) was to gather salient characteristics of academic domains from students' perspective. In Study 2 (N = 1709; 8th and 11th graders) the 13 characteristics identified in Study 1 were assessed along with academic emotions in four different domains (mathematics, physics, German, and English) using a questionnaire-based trait assessment. With respect to the same domains, state emotions were assessed in Study 3 (N = 121; 8th and 11th graders) by employing an experience sampling approach. In line with our initial assumptions, between-domain relations of trait but not state academic emotions reflected between-domain relations of domain characteristics. Implications for research and practice are discussed. PMID:25374547

  4. Between-Domain Relations of Students’ Academic Emotions and Their Judgments of School Domain Similarity

    Directory of Open Access Journals (Sweden)

    Thomas eGoetz

    2014-10-01

    Full Text Available With the aim to deepen our understanding of the between-domain relations of academic emotions, a series of three studies was conducted. We theorized that between-domain relations of trait (i.e., habitual emotions reflected students’ judgments of domain similarities, whereas between-domain relations of state (i.e., momentary emotions did not. This supposition was based on the accessibility model of emotional self-report, according to which individuals’ beliefs tend to strongly impact trait, but not state emotions. The aim of Study 1 (interviews; N = 40; 8th and 11th graders was to gather salient characteristics of academic domains from students’ perspective. In Study 2 (N=1709; 8th and 11th graders the 13 characteristics identified in Study 1 were assessed along with academic emotions in four different domains (mathematics, physics, German, and English using a questionnaire-based trait assessment. With respect to the same domains, state emotions were assessed in Study 3 (N = 121; 8th and 11th graders by employing an experience sampling approach. In line with our initial assumptions, between-domain relations of trait but not state academic emotions reflected between-domain relations of domain characteristics. Implications for research and practice are discussed.

  5. Protein function prediction using domain families.

    Science.gov (United States)

    Rentzsch, Robert; Orengo, Christine A

    2013-01-01

    Here we assessed the use of domain families for predicting the functions of whole proteins. These 'functional families' (FunFams) were derived using a protocol that combines sequence clustering with supervised cluster evaluation, relying on available high-quality Gene Ontology (GO) annotation data in the latter step. In essence, the protocol groups domain sequences belonging to the same superfamily into families based on the GO annotations of their parent proteins. An initial test based on enzyme sequences confirmed that the FunFams resemble enzyme (domain) families much better than do families produced by sequence clustering alone. For the CAFA 2011 experiment, we further associated the FunFams with GO terms probabilistically. All target proteins were first submitted to domain superfamily assignment, followed by FunFam assignment and, eventually, function assignment. The latter included an integration step for multi-domain target proteins. The CAFA results put our domain-based approach among the top ten of 31 competing groups and 56 prediction methods, confirming that it outperforms simple pairwise whole-protein sequence comparisons.

  6. Robust ferromagnetism carried by antiferromagnetic domain walls

    Science.gov (United States)

    Hirose, Hishiro T.; Yamaura, Jun-Ichi; Hiroi, Zenji

    2017-02-01

    Ferroic materials, such as ferromagnetic or ferroelectric materials, have been utilized as recording media for memory devices. A recent trend for downsizing, however, requires an alternative, because ferroic orders tend to become unstable for miniaturization. The domain wall nanoelectronics is a new developing direction for next-generation devices, in which atomic domain walls, rather than conventional, large domains themselves, are the active elements. Here we show that atomically thin magnetic domain walls generated in the antiferromagnetic insulator Cd2Os2O7 carry unusual ferromagnetic moments perpendicular to the wall as well as electron conductivity: the ferromagnetic moments are easily polarized even by a tiny field of 1 mT at high temperature, while, once cooled down, they are surprisingly robust even in an inverse magnetic field of 7 T. Thus, the magnetic domain walls could serve as a new-type of microscopic, switchable and electrically readable magnetic medium which is potentially important for future applications in the domain wall nanoelectronics.

  7. Structured hints : extracting and abstracting domain expertise.

    Energy Technology Data Exchange (ETDEWEB)

    Hereld, M.; Stevens, R.; Sterling, T.; Gao, G. R.; Mathematics and Computer Science; California Inst. of Tech.; Louisiana State Univ.; Univ. of Delaware

    2009-03-16

    We propose a new framework for providing information to help optimize domain-specific application codes. Its design addresses problems that derive from the widening gap between the domain problem statement by domain experts and the architectural details of new and future high-end computing systems. The design is particularly well suited to program execution models that incorporate dynamic adaptive methodologies for live tuning of program performance and resource utilization. This new framework, which we call 'structured hints', couples a vocabulary of annotations to a suite of performance metrics. The immediate target is development of a process by which a domain expert describes characteristics of objects and methods in the application code that would not be readily apparent to the compiler; the domain expert provides further information about what quantities might provide the best indications of desirable effect; and the interactive preprocessor identifies potential opportunities for the domain expert to evaluate. Our development of these ideas is progressing in stages from case study, through manual implementation, to automatic or semi-automatic implementation. In this paper we discuss results from our case study, an examination of a large simulation of a neural network modeled after the neocortex.

  8. Separating Cognitive and Content Domains in Mathematical Competence

    Science.gov (United States)

    Harks, Birgit; Klieme, Eckhard; Hartig, Johannes; Leiss, Dominik

    2014-01-01

    The present study investigates the empirical separability of mathematical (a) content domains, (b) cognitive domains, and (c) content-specific cognitive domains. There were 122 items representing two content domains (linear equations vs. theorem of Pythagoras) combined with two cognitive domains (modeling competence vs. technical competence)…

  9. Hidden Markov Models for Protein Domain Homology Identification and Analysis.

    Science.gov (United States)

    Jablonowski, Karl

    2017-01-01

    Protein domain identification and analysis are cornerstones of modern proteomics. The tools available to protein domain researchers avail a variety of approaches to understanding large protein domain families. Hidden Markov Models (HMM) form the basis for identifying and categorizing evolutionarily linked protein domains. Here I describe the use of HMM models for predicting and identifying Src Homology 2 (SH2) domains within the proteome.

  10. Domain-specific and domain-general processes in social perception--A complementary approach.

    Science.gov (United States)

    Michael, John; D'Ausilio, Alessandro

    2015-11-01

    In this brief discussion, we explicate and evaluate Heyes and colleagues' deflationary approach to interpreting apparent evidence of domain-specific processes for social perception. We argue that the deflationary approach sheds important light on how functionally specific processes in social perception can be subserved at least in part by domain-general processes. On the other hand, we also argue that the fruitfulness of this approach has been unnecessarily hampered by a contrastive conception of the relationship between domain-general and domain-specific processes. As an alternative, we propose a complementary conception: the identification of domain-general processes that are engaged in instances of social perception can play a positive, structuring role by adding additional constraints to be accounted for in modelling the domain-specific processes that are also involved in such instances. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Electric-field-driven dynamics of magnetic domain walls in magnetic nanowires patterned on ferroelectric domains

    OpenAIRE

    Wiele, Ben Van de; Leliaert, Jonathan; Franke, Kévin J A; Dijken, Sebastiaan van

    2016-01-01

    Strong coupling of magnetic domain walls onto straight ferroelastic boundaries of a ferroelectric layer enables full and reversible electric-field control of magnetic domain wall motion. In this paper, the dynamics of this new driving mechanism is analyzed using micromagnetic simulations. We show that transverse domain walls with a near-180° spin structure are stabilized in magnetic nanowires and that electric fields can move these walls with high velocities. Above a critical velocity, which ...

  12. Domain specialization: a post-training domain adaptation for Neural Machine Translation

    OpenAIRE

    Servan, Christophe; Crego, Josep; Senellart, Jean

    2016-01-01

    Domain adaptation is a key feature in Machine Translation. It generally encompasses terminology, domain and style adaptation, especially for human post-editing workflows in Computer Assisted Translation (CAT). With Neural Machine Translation (NMT), we introduce a new notion of domain adaptation that we call "specialization" and which is showing promising results both in the learning speed and in adaptation accuracy. In this paper, we propose to explore this approach under several perspectives.

  13. Low energy electron imaging of domains and domain walls in magnesium-doped lithium niobate

    Science.gov (United States)

    Nataf, G. F.; Grysan, P.; Guennou, M.; Kreisel, J.; Martinotti, D.; Rountree, C. L.; Mathieu, C.; Barrett, N.

    2016-09-01

    The understanding of domain structures, specifically domain walls, currently attracts a significant attention in the field of (multi)-ferroic materials. In this article, we analyze contrast formation in full field electron microscopy applied to domains and domain walls in the uniaxial ferroelectric lithium niobate, which presents a large 3.8 eV band gap and for which conductive domain walls have been reported. We show that the transition from Mirror Electron Microscopy (MEM - electrons reflected) to Low Energy Electron Microscopy (LEEM - electrons backscattered) gives rise to a robust contrast between domains with upwards (Pup) and downwards (Pdown) polarization, and provides a measure of the difference in surface potential between the domains. We demonstrate that out-of-focus conditions of imaging produce contrast inversion, due to image distortion induced by charged surfaces, and also carry information on the polarization direction in the domains. Finally, we show that the intensity profile at domain walls provides experimental evidence for a local stray, lateral electric field.

  14. Low energy electron imaging of domains and domain walls in magnesium-doped lithium niobate.

    Science.gov (United States)

    Nataf, G F; Grysan, P; Guennou, M; Kreisel, J; Martinotti, D; Rountree, C L; Mathieu, C; Barrett, N

    2016-09-09

    The understanding of domain structures, specifically domain walls, currently attracts a significant attention in the field of (multi)-ferroic materials. In this article, we analyze contrast formation in full field electron microscopy applied to domains and domain walls in the uniaxial ferroelectric lithium niobate, which presents a large 3.8 eV band gap and for which conductive domain walls have been reported. We show that the transition from Mirror Electron Microscopy (MEM - electrons reflected) to Low Energy Electron Microscopy (LEEM - electrons backscattered) gives rise to a robust contrast between domains with upwards (Pup) and downwards (Pdown) polarization, and provides a measure of the difference in surface potential between the domains. We demonstrate that out-of-focus conditions of imaging produce contrast inversion, due to image distortion induced by charged surfaces, and also carry information on the polarization direction in the domains. Finally, we show that the intensity profile at domain walls provides experimental evidence for a local stray, lateral electric field.

  15. Conversion of Dielectric Data from the Time Domain to the Frequency Domain

    Directory of Open Access Journals (Sweden)

    Vladimir Durman

    2005-01-01

    Full Text Available Polarisation and conduction processes in dielectric systems can be identified by the time domain or the frequency domain measurements. If the systems is a linear one, the results of the time domain measurements can be transformed into the frequency domain, and vice versa. Commonly, the time domain data of the absorption conductivity are transformed into the frequency domain data of the dielectric susceptibility. In practice, the relaxation are mainly evaluated by the frequency domain data. In the time domain, the absorption current measurement were prefered up to now. Recent methods are based on the recovery voltage measurements. In this paper a new method of the recovery data conversion from the time the frequency domain is proposed. The method is based on the analysis of the recovery voltage transient based on the Maxwell equation for the current density in a dielectric. Unlike the previous published solutions, the Laplace fransform was used to derive a formula suitable for practical purposes. the proposed procedure allows also calculating of the insulation resistance and separating the polarisation and conduction losses.

  16. Human-computer interface incorporating personal and application domains

    Science.gov (United States)

    Anderson, Thomas G [Albuquerque, NM

    2011-03-29

    The present invention provides a human-computer interface. The interface includes provision of an application domain, for example corresponding to a three-dimensional application. The user is allowed to navigate and interact with the application domain. The interface also includes a personal domain, offering the user controls and interaction distinct from the application domain. The separation into two domains allows the most suitable interface methods in each: for example, three-dimensional navigation in the application domain, and two- or three-dimensional controls in the personal domain. Transitions between the application domain and the personal domain are under control of the user, and the transition method is substantially independent of the navigation in the application domain. For example, the user can fly through a three-dimensional application domain, and always move to the personal domain by moving a cursor near one extreme of the display.

  17. Extracting meronomy relations from domain-specific, textual corporate databases

    NARCIS (Netherlands)

    Ittoo, R.A.; Bouma, G.; Maruster, L.; Wortmann, J.C.; Hopfe, C.J.; Rezgui, Y.; Métais, E.; Preece, A.; Li, H.

    2010-01-01

    Various techniques for learning meronymy relationships from open-domain corpora exist. However, extracting meronymy relationships from domain-specific, textual corporate databases has been overlooked, despite numerous application opportunities particularly in domains like product development and/or

  18. Human-computer interface incorporating personal and application domains

    Science.gov (United States)

    Anderson, Thomas G.

    2004-04-20

    The present invention provides a human-computer interface. The interface includes provision of an application domain, for example corresponding to a three-dimensional application. The user is allowed to navigate and interact with the application domain. The interface also includes a personal domain, offering the user controls and interaction distinct from the application domain. The separation into two domains allows the most suitable interface methods in each: for example, three-dimensional navigation in the application domain, and two- or three-dimensional controls in the personal domain. Transitions between the application domain and the personal domain are under control of the user, and the transition method is substantially independent of the navigation in the application domain. For example, the user can fly through a three-dimensional application domain, and always move to the personal domain by moving a cursor near one extreme of the display.

  19. Towards a continuous modeling of natural language domains

    OpenAIRE

    Ruder, Sebastian; Ghaffari, Parsa; Breslin, John G.

    2016-01-01

    Humans continuously adapt their style and language to a variety of domains. However, a reliable definition of `domain' has eluded researchers thus far. Additionally, the notion of discrete domains stands in contrast to the multiplicity of heterogeneous domains that humans navigate, many of which overlap. In order to better understand the change and variation of human language, we draw on research in domain adaptation and extend the notion of discrete domains to the continuous spectrum. We pro...

  20. Wavefield Extrapolation in Pseudo-depth Domain

    KAUST Repository

    Ma, Xuxin

    2011-12-11

    Wave-equation based seismic migration and inversion tools are widely used by the energy industry to explore hydrocarbon and mineral resources. By design, most of these techniques simulate wave propagation in a space domain with the vertical axis being depth measured from the surface. Vertical depth is popular because it is a straightforward mapping of the subsurface space. It is, however, not computationally cost-effective because the wavelength changes with local elastic wave velocity, which in general increases with depth in the Earth. As a result, the sampling per wavelength also increases with depth. To avoid spatial aliasing in deep fast media, the seismic wave is oversampled in shallow slow media and therefore increase the total computation cost. This issue is effectively tackled by using the vertical time axis instead of vertical depth. This is because in a vertical time representation, the "wavelength" is essentially time period for vertical rays. This thesis extends the vertical time axis to the pseudo-depth axis, which features distance unit while preserving the properties of the vertical time representation. To explore the potentials of doing wave-equation based imaging in the pseudo-depth domain, a Partial Differential Equation (PDE) is derived to describe acoustic wave in this new domain. This new PDE is inherently anisotropic because the use of a constant vertical velocity to convert between depth and vertical time. Such anisotropy results in lower reflection coefficients compared with conventional space domain modeling results. This feature is helpful to suppress the low wavenumber artifacts in reverse-time migration images, which are caused by the widely used cross-correlation imaging condition. This thesis illustrates modeling acoustic waves in both conventional space domain and pseudo-depth domain. The numerical tool used to model acoustic waves is built based on the lowrank approximation of Fourier integral operators. To investigate the potential

  1. Polar domain walls trigger magnetoelectric coupling.

    Science.gov (United States)

    Fontcuberta, Josep; Skumryev, Vassil; Laukhin, Vladimir; Granados, Xavier; Salje, Ekhard K H

    2015-09-21

    Interface physics in oxides heterostructures is pivotal in material's science. Domain walls (DWs) in ferroic systems are examples of naturally occurring interfaces, where order parameter of neighboring domains is modified and emerging properties may develop. Here we show that electric tuning of ferroelastic domain walls in SrTiO3 leads to dramatic changes of the magnetic domain structure of a neighboring magnetic layer (La1/2Sr1/2MnO3) epitaxially clamped on a SrTiO3 substrate. We show that the properties of the magnetic layer are intimately connected to the existence of polar regions at twin boundaries of SrTiO3, developing at , that can be electrically modulated. These findings illustrate that by exploiting the responsiveness of DWs nanoregions to external stimuli, even in absence of any domain contribution, prominent and adjustable macroscopic reactions of neighboring layers can be obtained. We conclude that polar DWs, known to exist in other materials, can be used to trigger tunable responses and may lead to new ways for the manipulation of interfacial emerging properties.

  2. The Private Legal Governance of Domain Names

    DEFF Research Database (Denmark)

    Schovsbo, Jens Hemmingsen

    2015-01-01

    Abstract This article evaluates the performance of the special private tribunals or panels such as the UDRP which have been developed within complicated systems of self- and co-regulation such as ICANN to decide disputes over domain names. It uses two different dispute resolution models viz. the ...... to be published in ”User Generated Law. Reconstructing Intellectual Property Law in a Knowledge Society” edited by Thomas Riis (forthcoming on Edward Elgar)....... on cases where trademarks are used as (parts of) domain names to express criticism of the trademark holder or the trademark itself (e.g. “TMsucks.com” / “lorteTM.dk”). The article is part of a research project on “User Generated Law” and uses the methodologies developed as part of this. It is scheduled....... the UDRP (WIPO) and the Danish Complaints Board for Internet Domain Names (the Board) to discuss how and to what extent the domain name system balances interests between trademark owners and other users of domain names and secures the rule of law (legal certainty and predictability) with a special focus...

  3. Observation of coupled magnetic and electric domains.

    Science.gov (United States)

    Fiebig, M; Lottermoser, Th; Fröhlich, D; Goltsev, A V; Pisarev, R V

    2002-10-24

    Ferroelectromagnets are an interesting group of compounds that complement purely (anti-)ferroelectric or (anti-)ferromagnetic materials--they display simultaneous electric and magnetic order. With this coexistence they supplement materials in which magnetization can be induced by an electric field and electrical polarization by a magnetic field, a property which is termed the magnetoelectric effect. Aside from its fundamental importance, the mutual control of electric and magnetic properties is of significant interest for applications in magnetic storage media and 'spintronics'. The coupled electric and magnetic ordering in ferroelectromagnets is accompanied by the formation of domains and domain walls. However, such a cross-correlation between magnetic and electric domains has so far not been observed. Here we report spatial maps of coupled antiferromagnetic and ferroelectric domains in YMnO3, obtained by imaging with optical second harmonic generation. The coupling originates from an interaction between magnetic and electric domain walls, which leads to a configuration that is dominated by the ferroelectromagnetic product of the order parameters.

  4. Generalized vector calculus on convex domain

    Science.gov (United States)

    Agrawal, Om P.; Xu, Yufeng

    2015-06-01

    In this paper, we apply recently proposed generalized integral and differential operators to develop generalized vector calculus and generalized variational calculus for problems defined over a convex domain. In particular, we present some generalization of Green's and Gauss divergence theorems involving some new operators, and apply these theorems to generalized variational calculus. For fractional power kernels, the formulation leads to fractional vector calculus and fractional variational calculus for problems defined over a convex domain. In special cases, when certain parameters take integer values, we obtain formulations for integer order problems. Two examples are presented to demonstrate applications of the generalized variational calculus which utilize the generalized vector calculus developed in the paper. The first example leads to a generalized partial differential equation and the second example leads to a generalized eigenvalue problem, both in two dimensional convex domains. We solve the generalized partial differential equation by using polynomial approximation. A special case of the second example is a generalized isoperimetric problem. We find an approximate solution to this problem. Many physical problems containing integer order integrals and derivatives are defined over arbitrary domains. We speculate that future problems containing fractional and generalized integrals and derivatives in fractional mechanics will be defined over arbitrary domains, and therefore, a general variational calculus incorporating a general vector calculus will be needed for these problems. This research is our first attempt in that direction.

  5. Cross domains Arabic named entity recognition system

    KAUST Repository

    Al-Ahmari, S. Saad

    2016-07-11

    Named Entity Recognition (NER) plays an important role in many Natural Language Processing (NLP) applications such as; Information Extraction (IE), Question Answering (QA), Text Clustering, Text Summarization and Word Sense Disambiguation. This paper presents the development and implementation of domain independent system to recognize three types of Arabic named entities. The system works based on a set of domain independent grammar-rules along with Arabic part of speech tagger in addition to gazetteers and lists of trigger words. The experimental results shown, that the system performed as good as other systems with better results in some cases of cross-domains corpora. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  6. Domain wall fringe field coupled spin logic

    Directory of Open Access Journals (Sweden)

    Yu-Ming Hung

    2016-12-01

    Full Text Available A class of spin logic devices based on the spin-orbit induced spin-transfer torques requires magnetic coupling between electrically isolated ferromagnetic elements. Here we use micromagnetic modeling to study the magnetic coupling induced by fringe fields from chiral domain walls in perpendicularly magnetized nanowires. These domains can be displaced using spin-orbit torques from a proximal heavy metal layer. For a 16 nm width wire that is 1 nm thick, we find that spin-orbit torques induced domain wall propagation can reliably switch a proximal 16 nm diameter 1 nm thick nanomagnet. These results show a promising means of implementing spin logic with spin-orbit torques using elements with perpendicular magnetization, which does not require an applied magnetic field.

  7. Bragg projection ptychography on niobium phase domains

    Science.gov (United States)

    Burdet, Nicolas; Shi, Xiaowen; Clark, Jesse N.; Huang, Xiaojing; Harder, Ross; Robinson, Ian

    2017-07-01

    Bragg projection ptychography (BPP) is a coherent x-ray diffraction imaging technique which combines the strengths of scanning microscopy with the phase contrast of x-ray ptychography. Here we apply it for high resolution imaging of the phase-shifted crystalline domains associated with epitaxial growth. The advantages of BPP are that the spatial extent of the sample is arbitrary, it is nondestructive, and it gives potentially diffraction limited spatial resolution. Here we demonstrate the application of BPP for revealing the domain structure caused by epitaxial misfit in a nanostructured metallic thin film. Experimental coherent diffraction data were collected from a niobium thin film, epitaxially grown on a sapphire substrate as the beam was scanned across the sample. The data were analyzed by BPP using a carefully selected combination of refinement procedures. The resulting image shows a close packed array of epitaxial domains, shifted with respect to each other due to misfit between the film and its substrate.

  8. Full traveltime inversion in source domain

    KAUST Repository

    Liu, Lu

    2017-06-01

    This paper presents a new method of source-domain full traveltime inversion (FTI). The objective of this study is automatically building near-surface velocity using the early arrivals of seismic data. This method can generate the inverted velocity that can kinetically best match the reconstructed plane-wave source of early arrivals with true source in source domain. It does not require picking first arrivals for tomography, which is one of the most challenging aspects of ray-based tomographic inversion. Besides, this method does not need estimate the source wavelet, which is a necessity for receiver-domain wave-equation velocity inversion. Furthermore, we applied our method on one synthetic dataset; the results show our method could generate a reasonable background velocity even when shingling first arrivals exist and could provide a good initial velocity for the conventional full waveform inversion (FWI).

  9. Transactions in domain-specific information systems

    Science.gov (United States)

    Zacek, Jaroslav

    2017-07-01

    Substantial number of the current information system (IS) implementations is based on transaction approach. In addition, most of the implementations are domain-specific (e.g. accounting IS, resource planning IS). Therefore, we have to have a generic transaction model to build and verify domain-specific IS. The paper proposes a new transaction model for domain-specific ontologies. This model is based on value oriented business process modelling technique. The transaction model is formalized by the Petri Net theory. First part of the paper presents common business processes and analyses related to business process modeling. Second part defines the transactional model delimited by REA enterprise ontology paradigm and introduces states of the generic transaction model. The generic model proposal is defined and visualized by the Petri Net modelling tool. Third part shows application of the generic transaction model. Last part of the paper concludes results and discusses a practical usability of the generic transaction model.

  10. Multi-Domain Modeling Based on Modelica

    Directory of Open Access Journals (Sweden)

    Liu Jun

    2016-01-01

    Full Text Available With the application of simulation technology in large-scale and multi-field problems, multi-domain unified modeling become an effective way to solve these problems. This paper introduces several basic methods and advantages of the multidisciplinary model, and focuses on the simulation based on Modelica language. The Modelica/Mworks is a newly developed simulation software with features of an object-oriented and non-casual language for modeling of the large, multi-domain system, which makes the model easier to grasp, develop and maintain.It This article shows the single degree of freedom mechanical vibration system based on Modelica language special connection mechanism in Mworks. This method that multi-domain modeling has simple and feasible, high reusability. it closer to the physical system, and many other advantages.

  11. A Domain Description Language for Data Processing

    Science.gov (United States)

    Golden, Keith

    2003-01-01

    We discuss an application of planning to data processing, a planning problem which poses unique challenges for domain description languages. We discuss these challenges and why the current PDDL standard does not meet them. We discuss DPADL (Data Processing Action Description Language), a language for describing planning domains that involve data processing. DPADL is a declarative, object-oriented language that supports constraints and embedded Java code, object creation and copying, explicit inputs and outputs for actions, and metadata descriptions of existing and desired data. DPADL is supported by the IMAGEbot system, which we are using to provide automation for an ecological forecasting application. We compare DPADL to PDDL and discuss changes that could be made to PDDL to make it more suitable for representing planning domains that involve data processing actions.

  12. Dispersive Stiffness of Dzyaloshinskii Domain Walls

    Science.gov (United States)

    Pellegren, J. P.; Lau, D.; Sokalski, V.

    2017-07-01

    It is well documented that subjecting perpendicular magnetic films that exhibit the interfacial Dzyaloshinskii-Moriya interaction to an in-plane magnetic field results in a domain wall (DW) energy σ , which is highly anisotropic with respect to the orientation of the DW in the film plane Θ . We demonstrate that this anisotropy has a profound impact on the elastic response of the DW as characterized by the surface stiffness σ ˜ (Θ )=σ (Θ )+σ''(Θ ) and evaluate its dependence on the length scale of deformation. The influence of stiffness on DW mobility in the creep regime is assessed, with analytic and numerical calculations showing trends in σ ˜ that better represent experimental measurements of domain wall velocity in magnetic thin films compared to σ alone. Our treatment provides experimental support for theoretical models of the mobility of anisotropic elastic manifolds and makes progress toward a more complete understanding of magnetic domain wall creep.

  13. Gravitational waves from Higgs domain walls

    Directory of Open Access Journals (Sweden)

    Naoya Kitajima

    2015-05-01

    Full Text Available The effective potential for the Standard Model Higgs field allows two quasi-degenerate vacua; one is our vacuum at the electroweak scale, while the other is at a much higher scale. The latter minimum may be at a scale much smaller than the Planck scale, if the potential is lifted by new physics. This gives rise to a possibility of domain wall formation after inflation. If the high-scale minimum is a local minimum, domain walls are unstable and disappear through violent annihilation processes, producing a significant amount of gravitational waves. We estimate the amount of gravitational waves produced from unstable domain walls in the Higgs potential and discuss detectability with future experiments.

  14. On thick domain walls in general relativity

    Science.gov (United States)

    Goetz, Guenter; Noetzold, Dirk

    1989-01-01

    Planar scalar field configurations in general relativity differ considerably from those in flat space. It is shown that static domain walls of finite thickness in curved space-time do not possess a reflection symmetry. At infinity, the space-time tends to the Taub vacuum on one side of the wall and to the Minkowski vacuum (Rindler space-time) on the other. Massive test particles are always accelerated towards the Minkowski side, i.e., domain walls are attractive on the Taub side, but repulsive on the Minkowski side (Taub-vacuum cleaner). It is also proved that the pressure in all directions is always negative. Finally, a brief comment is made concerning the possibility of infinite, i.e., bigger than horizon size, domain walls in our universe. All of the results are independent of the form of the potential V(phi) greater than or equal to 0 of the scalar field phi.

  15. Work-domain knowledge in usability evaluation

    DEFF Research Database (Denmark)

    Følstad, Asbjørn; Hornbæk, Kasper

    2010-01-01

    Usability evaluation helps to determine whether interactive systems support users in their work tasks. However, knowledge about those tasks and, more generally, about the work-domain is difficult to bring to bear on the processes and outcome of usability evaluation. One way to include such work......-domain knowledge might be Cooperative Usability Testing, an evaluation method that consists of (a) interaction phases, similar to classic usability testing, and (b) interpretation phases, where the test participant and the moderator discuss incidents and experiences from the interaction phases. We have studied...... whether such interpretation phases improve the relevance of usability evaluations in the development of work-domain specific systems. The study included two development cases. We conclude that the interpretation phases generate additional insight and redesign suggestions related to observed usability...

  16. Domain Specific Language Support for Exascale

    Energy Technology Data Exchange (ETDEWEB)

    Mellor-Crummey, John [Rice Univ., Houston, TX (United States)

    2017-10-20

    A multi-institutional project known as D-TEC (short for “Domain- specific Technology for Exascale Computing”) set out to explore technologies to support the construction of Domain Specific Languages (DSLs) to map application programs to exascale architectures. DSLs employ automated code transformation to shift the burden of delivering portable performance from application programmers to compilers. Two chief properties contribute: DSLs permit expression at a high level of abstraction so that a programmer’s intent is clear to a compiler and DSL implementations encapsulate human domain-specific optimization knowledge so that a compiler can be smart enough to achieve good results on specific hardware. Domain specificity is what makes these properties possible in a programming language. If leveraging domain specificity is the key to keep exascale software tractable, a corollary is that many different DSLs will be needed to encompass the full range of exascale computing applications; moreover, a single application may well need to use several different DSLs in conjunction. As a result, developing a general toolkit for building domain-specific languages was a key goal for the D-TEC project. Different aspects of the D-TEC research portfolio were the focus of work at each of the partner institutions in the multi-institutional project. D-TEC research and development work at Rice University focused on on three principal topics: understanding how to automate the tuning of code for complex architectures, research and development of the Rosebud DSL engine, and compiler technology to support complex execution platforms. This report provides a summary of the research and development work on the D-TEC project at Rice University.

  17. Changing domains in human capital measurement

    Directory of Open Access Journals (Sweden)

    Pharny D. Chrysler-Fox

    2014-02-01

    Full Text Available Orientation: The management context is dynamic; this is especially evident in human capital as the primary source of value creation as opposed to physical and natural resources. In response, measurement methodologies have moved from a transactional approach (strategy implementation to a transformational approach (human capital contribution paradigm, as well as diverging into different purposes. To date, there has been little overlap on recent domains to consider in managing and measuring the contribution of the human resource function and employees, and how to unlock and add value.Research purpose: The aim of the study was to explore and describe changing domains within human capital management to be managed and measured.Motivation for the study: The motivation was to advance the understanding of changing measurement domains to aid practitioners to manage and measure the contribution of the human resource function and employees, in order to unlock and add value and ultimately contribute to the success of an organisation.Research design, approach and method: Unstructured, in-depth interview data of purposively selected cases from a selected panel of human resource practitioners specialising in human capital measurement was thematically analysed in this exploratory-descriptive investigation.Main findings: Findings suggested that seven domains should be managed and measured. These domains highlight new areas of impact and levels of management. In addition, crossdomain relationships in measurement allow for an understanding of the impact and potential value on which to capitalise.Practical/managerial implications: New domains to manage and measure focus the attention of practitioners beyond the transactional performance management paradigm to a transformational approach to influence the business strategy. Higher education institutions need to develop students’ cognitive skills to facilitate systems thinking.Contribution: This study suggests a new

  18. Design PID controllers for desired time-domain or frequency-domain response.

    Science.gov (United States)

    Zhang, Weidong; Xi, Yugeng; Yang, Genke; Xu, Xiaoming

    2002-10-01

    Practical requirements on the design of control systems, especially process control systems, are usually specified in terms of time-domain response, such as overshoot and rise time, or frequency-domain response, such as resonance peak and stability margin. Although numerous methods have been developed for the design of the proportional-integral-derivative (PID) controller, little work has been done in relation to the quantitative time-domain and frequency-domain responses. In this paper, we study the following problem: Given a nominal stable process with time delay, we design a suboptimal PID controller to achieve the required time-domain response or frequency-domain response for the nominal system or the uncertain system. An H(infinity) PID controller is developed based on optimal control theory and the parameters are derived analytically. Its properties are investigated and compared with that of two developed suboptimal controllers: an H2 PID controller and a Maclaurin PID controller. It is shown that all three controllers can provide the quantitative time-domain and frequency-domain responses.

  19. SH3 Domains Differentially Stimulate Distinct Dynamin I Assembly Modes and G Domain Activity.

    Directory of Open Access Journals (Sweden)

    Sai Krishnan

    Full Text Available Dynamin I is a highly regulated GTPase enzyme enriched in nerve terminals which mediates vesicle fission during synaptic vesicle endocytosis. One regulatory mechanism involves its interactions with proteins containing Src homology 3 (SH3 domains. At least 30 SH3 domain-containing proteins bind dynamin at its proline-rich domain (PRD. Those that stimulate dynamin activity act by promoting its oligomerisation. We undertook a systematic parallel screening of 13 glutathione-S-transferase (GST-tagged endocytosis-related SH3 domains on dynamin binding, GTPase activity and oligomerisation. No correlation was found between dynamin binding and their potency to stimulate GTPase activity. There was limited correlation between the extent of their ability to stimulate dynamin activity and the level of oligomerisation, indicating an as yet uncharacterised allosteric coupling of the PRD and G domain. We examined the two variants, dynamin Iab and Ibb, which differ in the alternately splice middle domain α2 helix. They responded differently to the panel of SH3s, with the extent of stimulation between the splice variants varying greatly between the SH3s. This study reveals that SH3 binding can act as a heterotropic allosteric regulator of the G domain via the middle domain α2 helix, suggesting an involvement of this helix in communicating the PRD-mediated allostery. This indicates that SH3 binding both stabilises multiple conformations of the tetrameric building block of dynamin, and promotes assembly of dynamin-SH3 complexes with distinct rates of GTP hydrolysis.

  20. Matter antimatter domains: A possible solution to the CP domain wall problem in the early universe

    Science.gov (United States)

    Mohanty, A. K.; Stecker, F. W.

    1984-01-01

    An SU(5) grand unified theory model is used to show how the degeneracy between vacua with different spontaneously broken charge parity can be dynamically lifted by a condensate of heavy fermion pairs. This drives a phase transition to a unique vacuum state with definite charge parity. The transition eliminates the domain walls in a matter antimatter symmetric domain cosmology.

  1. Intellectual Growth in Children as a Function of Domain Specific and Domain General Working Memory Subgroups

    Science.gov (United States)

    Swanson, H. Lee

    2011-01-01

    This study examined whether children's growth on measures of fluid (Raven Colored Progressive Matrices) and crystallized (reading and math achievement) intelligence was attributable to domain-specific or domain-general functions of working memory (WM). A sample of 290 elementary school children was tested on measures of intelligence across three…

  2. PTEN-PDZ domain interactions: Binding of PTEN to PDZ domains of PTPN13.

    NARCIS (Netherlands)

    Sotelo, N.S.; Schepens, J.T.G.; Valiente, M.; Hendriks, W.J.A.J.; Pulido, R.

    2015-01-01

    Protein modular interactions mediated by PDZ domains are essential for the establishment of functional protein networks controlling diverse cellular functions. The tumor suppressor PTEN possesses a C-terminal PDZ-binding motif (PDZ-BM) that is recognized by a specific set of PDZ domains from

  3. Detecting broad domains and narrow peaks in ChIP-seq data with hiddenDomains.

    Science.gov (United States)

    Starmer, Joshua; Magnuson, Terry

    2016-03-24

    Correctly identifying genomic regions enriched with histone modifications and transcription factors is key to understanding their regulatory and developmental roles. Conceptually, these regions are divided into two categories, narrow peaks and broad domains, and different algorithms are used to identify each one. Datasets that span these two categories are often analyzed with a single program for peak calling combined with an ad hoc method for domains. We developed hiddenDomains, which identifies both peaks and domains, and compare it to the leading algorithms using H3K27me3, H3K36me3, GABP, ESR1 and FOXA ChIP-seq datasets. The output from the programs was compared to qPCR-validated enriched and depleted sites, predicted transcription factor binding sites, and highly-transcribed gene bodies. With every method, hiddenDomains, performed as well as, if not better than algorithms dedicated to a specific type of analysis. hiddenDomains performs as well as the best domain and peak calling algorithms, making it ideal for analyzing ChIP-seq datasets, especially those that contain a mixture of peaks and domains.

  4. Model checking of healthcare domain models.

    Science.gov (United States)

    Baksi, Dibyendu

    2009-12-01

    This paper shows the application of a type of formal software verification technique known as lightweight model checking to a domain model in healthcare informatics in general and public health surveillance systems in particular. One of the most complex use cases of such a system is checked using assertions to verify one important system property. This use case is one of the major justifications for the complexity of the domain model. Alloy Analyzer verification tool is utilized for this purpose. Such verification work is very effective in either uncovering design flaws or in providing guarantees on certain desirable system properties in the earlier phases of the development lifecycle of any critical project.

  5. Vector domain decomposition schemes for parabolic equations

    Science.gov (United States)

    Vabishchevich, P. N.

    2017-09-01

    A new class of domain decomposition schemes for finding approximate solutions of timedependent problems for partial differential equations is proposed and studied. A boundary value problem for a second-order parabolic equation is used as a model problem. The general approach to the construction of domain decomposition schemes is based on partition of unity. Specifically, a vector problem is set up for solving problems in individual subdomains. Stability conditions for vector regionally additive schemes of first- and second-order accuracy are obtained.

  6. [Development of domain specific search engines].

    Science.gov (United States)

    Takai, T; Tokunaga, M; Maeda, K; Kaminuma, T

    2000-01-01

    As cyber space exploding in a pace that nobody has ever imagined, it becomes very important to search cyber space efficiently and effectively. One solution to this problem is search engines. Already a lot of commercial search engines have been put on the market. However these search engines respond with such cumbersome results that domain specific experts can not tolerate. Using a dedicate hardware and a commercial software called OpenText, we have tried to develop several domain specific search engines. These engines are for our institute's Web contents, drugs, chemical safety, endocrine disruptors, and emergent response for chemical hazard. These engines have been on our Web site for testing.

  7. Magnetic domains the analysis of magnetic microstructures

    CERN Document Server

    Hubert, Alex

    1998-01-01

    The book gives a systematic and comprehensive survey of the complete area of magnetic microstructures. It reaches from micromagnetism of nanoparticles to complex structures of extended magnetic materials. The book starts with a comprehensive evaluation of traditional and modern experimental methods for the observation of magnetic domains and continues with the treatment of important methods for the theoretical analysis of magnetic microcstructures. A survey of the necessary techniques in materials characterization is given. The book offers an observation and analysis of magnetic domains in all

  8. The different roles of aggrecan interaction domains

    DEFF Research Database (Denmark)

    Aspberg, Anders

    2012-01-01

    is vital in that it binds the proteoglycan to hyaluronan in ternary complex with link protein, retaining the proteoglycan in the tissue. The importance of the C-terminal G3 domain interactions has recently been emphasized by two different human hereditary disorders: autosomal recessive aggrecan......-type spondyloepimetaphyseal dysplasia and autosomal dominant familial osteochondritis dissecans. In these two conditions, different missense mutations in the aggrecan C-type lectin repeat have been described. The resulting amino acid replacements affect the ligand interactions of the G3 domain, albeit with widely different...

  9. Clojure for domain-specific languages

    CERN Document Server

    Kelker, Ryan D

    2013-01-01

    An example-oriented approach to develop custom domain-specific languages.If you've already developed a few Clojure applications and wish to expand your knowledge on Clojure or domain-specific languages in general, then this book is for you. If you're an absolute Clojure beginner, then you may only find the detailed examples of the core Clojure components of value. If you've developed DSLs in other languages, this Lisp and Java-based book might surprise you with the power of Clojure.

  10. Fake supergravity and domain wall stability

    Science.gov (United States)

    Freedman, D. Z.; Núñez, C.; Schnabl, M.; Skenderis, K.

    2004-05-01

    We review the generalized Witten-Nester spinor stability argument for flat domain wall solutions of gravitational theories. Neither the field theory nor the solution need be supersymmetric. Nor is the space-time dimension restricted. We develop the nontrivial extension required for AdS-sliced domain walls and apply this to show that the recently proposed “Janus” solution of type-IIB supergravity is stable nonperturbatively for a broad class of deformations. Generalizations of this solution to arbitrary dimension and a simple curious linear dilaton solution of type-IIB supergravity are by-products of this work.

  11. Software For Multivariable Frequency-Domain Analysis

    Science.gov (United States)

    Armstrong, Ernest S.; Giesy, Daniel P.

    1991-01-01

    FREQ (Multivariable Frequency Domain Singular Value Analysis Package) software package of subroutines performing frequency-domain analysis of: continuous- or discrete-multivariable linear systems; any continuous system for which one calculates transfer matrix at points on imaginary axis; or any discrete system for which one calculates transfer matrix at points on unit circle. Four different versions available. Single-precision brief version LAR-14119, single-precision complete version LAR-14120, double-precision brief version LAR-14121, and double-precision complete version LAR-14122. Written in ANSI standard FORTRAN 77.

  12. Small domain-size multiblock copolymer electrolytes

    Science.gov (United States)

    Pistorino, Jonathan; Eitouni, Hany Basam

    2016-09-20

    New block polymer electrolytes have been developed which have higher conductivities than previously reported for other block copolymer electrolytes. The new materials are constructed of multiple blocks (>5) of relatively low domain size. The small domain size provides greater protection against formation of dendrites during cycling against lithium in an electrochemical cell, while the large total molecular weight insures poor long range alignment, which leads to higher conductivity. In addition to higher conductivity, these materials can be more easily synthesized because of reduced requirements on the purity level of the reagents.

  13. XLOS-observed mutations of MID1 Bbox1 domain cause domain unfolding.

    Directory of Open Access Journals (Sweden)

    Katharine M Wright

    Full Text Available MID1 catalyzes the ubiquitination of the protein alpha4 and the catalytic subunit of protein phosphatase 2A. Mutations within the MID1 Bbox1 domain are associated with X-linked Opitz G syndrome (XLOS. Our functional assays have shown that mutations of Ala130 to Val or Thr, Cys142 to Ser and Cys145 to Thr completely disrupt the polyubiquitination of alpha4. Using NMR spectroscopy, we characterize the effect of these mutations on the tertiary structure of the Bbox1 domain by itself and in tandem with the Bbox2 domain. The mutation of either Cys142 or Cys145, each of which is involved in coordinating one of the two zinc ions, results in the collapse of signal dispersion in the HSQC spectrum of the Bbox1 domain indicating that the mutant protein structure is unfolded. Each mutation caused the coordination of both zinc ions, which are ∼ 13 Å apart, to be lost. Although Ala130 is not involved in the coordination of a zinc ion, the Ala130Thr mutant Bbox1 domain yields a poorly dispersed HSQC spectrum similar to those of the Cys142Ser and Cys145Thr mutants. Interestingly, neither cysteine mutation affects the structure of the adjacent Bbox2 domain when the two Bbox domains are engineered in their native tandem Bbox1-Bbox2 protein construct. Dynamic light scattering measurements suggest that the mutant Bbox1 domain has an increased propensity to form aggregates compared to the wild type Bbox1 domain. These studies provide insight into the mechanism by which mutations observed in XLOS affect the structure and function of the MID1 Bbox1 domain.

  14. Theory of topological edges and domain walls

    NARCIS (Netherlands)

    Bais, F.A.; Slingerland, J.K.; Haaker, S.M.

    2009-01-01

    We investigate domain walls between topologically ordered phases in two spatial dimensions. We present a method which allows for the determination of the superselection sectors of excitations of such walls and which leads to a unified description of the kinematics of a wall and the two phases to

  15. A metamodel for mobile forensics investigation domain

    Science.gov (United States)

    Abd Razak, Shukor; Othman, Siti Hajar; Mohammed, Arafat; Saeed, Faisal

    2017-01-01

    With the rapid development of technology, mobile phones have become an essential tool in terms of crime fighting and criminal investigation. However, many mobile forensics investigators face difficulties with the investigation process in their domain. These difficulties are due to the heavy reliance of the forensics field on knowledge which, although a valuable resource, is scattered and widely dispersed. The wide dispersion of mobile forensics knowledge not only makes investigation difficult for new investigators, resulting in substantial waste of time, but also leads to ambiguity in the concepts and terminologies of the mobile forensics domain. This paper developed an approach for mobile forensics domain based on metamodeling. The developed approach contributes to identify common concepts of mobile forensics through a development of the Mobile Forensics Metamodel (MFM). In addion, it contributes to simplifying the investigation process and enables investigation teams to capture and reuse specialized forensic knowledge, thereby supporting the training and knowledge management activities. Furthermore, it reduces the difficulty and ambiguity in the mobile forensics domain. A validation process was performed to ensure the completeness and correctness of the MFM. The validation was conducted using two techniques for improvements and adjustments to the metamodel. The last version of the adjusted metamodel was named MFM 1.2. PMID:28445486

  16. Behavioural domain knowledge transfer for autonomous agents

    CSIR Research Space (South Africa)

    Rosman, Benjamin S

    2014-11-01

    Full Text Available task independent behaviour model based on the underlying structure of a domain which is common across multiple tasks presented to an autonomous agent. Our approach involves learning action priors: a behavioural model which encodes a notion of local...

  17. Ecological Automation Design, Extending Work Domain Analysis

    NARCIS (Netherlands)

    Amelink, M.H.J.

    2010-01-01

    In high–risk domains like aviation, medicine and nuclear power plant control, automation has enabled new capabilities, increased the economy of operation and has greatly contributed to safety. However, automation increases the number of couplings in a system, which can inadvertently lead to more

  18. Nanoscale Membrane Domain Formation Driven by Cholesterol

    DEFF Research Database (Denmark)

    Javanainen, Matti; Martinez-Seara, Hector; Vattulainen, Ilpo

    2017-01-01

    . The complex nanodomain substructure forms when cholesterol positions itself in the domain boundary region. Here cholesterol can also readily flip-flop across the membrane. Most importantly, replacing cholesterol with a sterol characterized by a less asymmetric ring region impairs the emergence of nanodomains...

  19. Genomewide analysis of LATERAL ORGAN BOUNDARIES Domain ...

    Indian Academy of Sciences (India)

    2014-04-23

    Apr 23, 2014 ... State Key Laboratory of Crop Biology, Shandong Agricultural University, Taian, Shandong 271018,. People's Republic of ... finger-like-domain transcription factor family, and regulate diverse biological processes in plants. However, little is ...... Letunic I., Doerks T. and Bork P. 2012 SMART 7: recent updates.

  20. Conceptualizing Indicator Domains for Evaluating Action Research

    Science.gov (United States)

    Piggot-Irvine, Eileen; Rowe, Wendy; Ferkins, Lesley

    2015-01-01

    The focus of this paper is to share thinking about meta-level evaluation of action research (AR), and to introduce indicator domains for assessing and measuring inputs, outputs and outcomes. Meta-level and multi-site evaluation has been rare in AR beyond project implementation and participant satisfaction. The paper is the first of several…

  1. Domain-specific knowledge as playful interaction

    DEFF Research Database (Denmark)

    Valente, Andrea; Marchetti, Emanuela

    2015-01-01

    the design process of Prime Slaughter, to move further in developing a general approach in developing games, aimed at effectively conveying knowledge from a specific domain. Hence this paper will discuss the past design process, as a concrete case, and then formulate a theoretical framework, based...

  2. Domain decomposition methods for hyperbolic problems

    Indian Academy of Sciences (India)

    In this paper a method is developed for solving hyperbolic initial boundary value problems in one space dimension using domain decomposition, which can be extended to problems in several space dimensions. We minimize a functional which is the sum of squares of the 2 norms of the residuals and a term which is the ...

  3. Domain wall dynamics of magnetically bistable microwires

    Directory of Open Access Journals (Sweden)

    Ipatov M.

    2012-06-01

    Full Text Available We studied domain wall propagation of magnetically-bistable Fe- Co-rich microwires paying attention on effect of applied and internal stresses. We measured hysteresis loops and domain wall propagation in various magnetic Fe- Co-rich amorphous microwires with metallic nucleus diameters (from 12 □m till 22 □m using Sixtus Tonks-like experiments. Application of tensile stresses results in decreasing of domain wall velocity. We discussed magnetoelastic contribution in dynamics of domain wall propagation. We observed, that microwires with different geometries exhibit v(H dependences with different slopes. Application of stresses resulted in decrease of DW velocity, v, and DW mobility S. Quite fast DW propagation (v till 2500 m/s at H about 30 A/m has been observed in low magnetostrictive magnetically bistable Co56Fe8Ni10Si110B16 microwires. Consequently, we can assume that generally magnetoelastic energy affects DW dynamics: decreasing magnetoelastic energy, Kme, DW velocity increases.

  4. Vector solitons with an embedded domain wall

    NARCIS (Netherlands)

    Kevrekidis, P.G.; Susanto, H.; Carretero-Gonzalez, R.; Malomed, B.A.; Frantzeskakis, D.J.

    2005-01-01

    We present a class of soliton solutions to a system of two coupled nonlinear Schrödinger equations, with an intrinsic domain wall (DW) which separates regions occupied by two different fields. The model describes a binary mixture of two Bose-Einstein condensates (BECs) with interspecies repulsion.

  5. Leptogenesis with left-right domain walls

    Indian Academy of Sciences (India)

    the scale of left-right symmetry breaking. Keywords. Leptogenesis; baryogenesis; domain walls; left-right symmetry. PACS Nos 12.10.Dm; 98.80.Cq; 98.80.Ft. Explaining the observed baryon asymmetry of the Universe within the framework of gauge theories and the standard Big Bang cosmology remains an open problem.

  6. Load Estimation by Frequency Domain Decomposition

    DEFF Research Database (Denmark)

    Pedersen, Ivar Chr. Bjerg; Hansen, Søren Mosegaard; Brincker, Rune

    2007-01-01

    When performing operational modal analysis the dynamic loading is unknown, however, once the modal properties of the structure have been estimated, the transfer matrix can be obtained, and the loading can be estimated by inverse filtering. In this paper loads in frequency domain are estimated...... and the errors on the estimated loads are determined....

  7. Learning domain abstractions for long lived robots

    CSIR Research Space (South Africa)

    Rosman, Benjamin S

    2014-06-01

    Full Text Available . This thesis aims to address the major question: what are the domain invariances which should be learnt by a long lived agent which encounters a range of different tasks? This question can be decomposed into three dimensions for learning invariances, based...

  8. Structural Time Domain Identification Toolbox User's Guide

    DEFF Research Database (Denmark)

    Andersen, P.; Kirkegaard, Poul Henning; Brincker, Rune

    This manual describes the Structural Time Domain Identification toolbox for use with MA TLAB. This version of the tool box has been developed using the PC-based MA TLAB version 4.2c, but is compatible with prior versions of MATLAB and UNIX-based versions. The routines of the toolbox are the so...

  9. Scalable Domain Decomposed Monte Carlo Particle Transport

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Matthew Joseph [Univ. of California, Davis, CA (United States)

    2013-12-05

    In this dissertation, we present the parallel algorithms necessary to run domain decomposed Monte Carlo particle transport on large numbers of processors (millions of processors). Previous algorithms were not scalable, and the parallel overhead became more computationally costly than the numerical simulation.

  10. Enhanced functional and structural domain assignments using ...

    Indian Academy of Sciences (India)

    The sequencing of the Mycobacterium tuberculosis (MTB) H37Rv genome has facilitated deeper insights into the biology of MTB, yet the functions of many MTB proteins are unknown. We have used sensitive profile-based search procedures to assign functional and structural domains to infer functions of gene products ...

  11. Towards Clone Detection in UML Domain Models

    DEFF Research Database (Denmark)

    Störrle, Harald

    2010-01-01

    , we discuss how model clones arise by analyzing several practical scenarios. We propose a formal definition of models and clones, that allows us to specify a generic clone detection algorithm. Through a thorough analysis of the detail structure of sample UML domain models, recommendations for clone...

  12. Single Domain Antibodies as New Biomarker Detectors

    Directory of Open Access Journals (Sweden)

    Chiuan Herng Leow

    2017-10-01

    Full Text Available Biomarkers are defined as indicators of biological processes, pathogenic processes, or pharmacological responses to a therapeutic intervention. Biomarkers have been widely used for early detection, prediction of response after treatment, and for monitoring the progression of diseases. Antibodies represent promising tools for recognition of biomarkers, and are widely deployed as analytical tools in clinical settings. For immunodiagnostics, antibodies are now exploited as binders for antigens of interest across a range of platforms. More recently, the discovery of antibody surface display and combinatorial chemistry techniques has allowed the exploration of new binders from a range of animals, for instance variable domains of new antigen receptors (VNAR from shark and variable heavy chain domains (VHH or nanobodies from camelids. These single domain antibodies (sdAbs have some advantages over conventional murine immunoglobulin owing to the lack of a light chain, making them the smallest natural biomarker binders thus far identified. In this review, we will discuss several biomarkers used as a means to validate diseases progress. The potential functionality of modern singe domain antigen binders derived from phylogenetically early animals as new biomarker detectors for current diagnostic and research platforms development will be described.

  13. Towards Public Domain Management of Liberation Movement ...

    African Journals Online (AJOL)

    ... appropriate acquisition for long term public domain management of the liberation movement archives that are currently managed ineffectively by various private archives in the region. The study recommends that such archives, because of their national heritage importance, should be decommissioned from private custody ...

  14. Domains involved in TAF15 subcellular localisation

    DEFF Research Database (Denmark)

    Marko, Marija; Vlassis, Arsenios; Guialis, Apostolia

    2012-01-01

    to play important roles in the onset of specific tumours, certain forms of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). In this study we identified the domains of TAF15 responsible for its subcellular localisation in human (HeLa) cells and experimentally confirmed...

  15. Membrane domains and polarized trafficking of sphingolipids

    NARCIS (Netherlands)

    Maier, O; Slimane, TA; Hoekstra, D

    The plasma membrane of polarized cells consists of distinct domains, the apical and basolateral membrane that are characterized by a distinct lipid and protein content. Apical protein transport is largely mediated by (glyco)sphingolipid-cholesterol enriched membrane microdomains, so called rafts. In

  16. Desiderata for domain reference ontologies in biomedicine.

    Science.gov (United States)

    Burgun, Anita

    2006-06-01

    Domain reference ontologies represent knowledge about a particular part of the world in a way that is independent from specific objectives, through a theory of the domain. An example of reference ontology in biomedical informatics is the Foundational Model of Anatomy (FMA), an ontology of anatomy that covers the entire range of macroscopic, microscopic, and subcellular anatomy. The purpose of this paper is to explore how two domain reference ontologies--the FMA and the Chemical Entities of Biological Interest (ChEBI) ontology, can be used (i) to align existing terminologies, (ii) to infer new knowledge in ontologies of more complex entities, and (iii) to manage and help reasoning about individual data. We analyze those kinds of usages of these two domain reference ontologies and suggest desiderata for reference ontologies in biomedicine. While a number of groups and communities have investigated general requirements for ontology design and desiderata for controlled medical vocabularies, we are focusing on application purposes. We suggest five desirable characteristics for reference ontologies: good lexical coverage, good coverage in terms of relations, compatibility with standards, modularity, and ability to represent variation in reality.

  17. Compactified webs and domain wall partition functions

    Energy Technology Data Exchange (ETDEWEB)

    Shabbir, Khurram [Government College University, Department of Mathematics, Lahore (Pakistan)

    2017-04-15

    In this paper we use the topological vertex formalism to calculate a generalization of the ''domain wall'' partition function of M-strings. This generalization allows calculation of partition function of certain compactified webs using a simple gluing algorithm similar to M-strings case. (orig.)

  18. Magnetoresistance in magnetic domain wall systems

    NARCIS (Netherlands)

    Jonkers, PAE

    The contribution to the magneto resistance (MR) was calculated for a single magnetic domain wall present in a small 2D impure ferromagnetic wire. On assuming low-temperatures and spin-independent impurity scattering the mechanism responsible for a positive contribution to MR is quantum interference.

  19. Anisotropic conductance at improper ferroelectric domain walls.

    Science.gov (United States)

    Meier, D; Seidel, J; Cano, A; Delaney, K; Kumagai, Y; Mostovoy, M; Spaldin, N A; Ramesh, R; Fiebig, M

    2012-02-26

    Transition metal oxides hold great potential for the development of new device paradigms because of the field-tunable functionalities driven by their strong electronic correlations, combined with their earth abundance and environmental friendliness. Recently, the interfaces between transition-metal oxides have revealed striking phenomena, such as insulator-metal transitions, magnetism, magnetoresistance and superconductivity. Such oxide interfaces are usually produced by sophisticated layer-by-layer growth techniques, which can yield high-quality, epitaxial interfaces with almost monolayer control of atomic positions. The resulting interfaces, however, are fixed in space by the arrangement of the atoms. Here we demonstrate a route to overcoming this geometric limitation. We show that the electrical conductance at the interfacial ferroelectric domain walls in hexagonal ErMnO(3) is a continuous function of the domain wall orientation, with a range of an order of magnitude. We explain the observed behaviour using first-principles density functional and phenomenological theories, and relate it to the unexpected stability of head-to-head and tail-to-tail domain walls in ErMnO(3) and related hexagonal manganites. As the domain wall orientation in ferroelectrics is tunable using modest external electric fields, our finding opens a degree of freedom that is not accessible to spatially fixed interfaces.

  20. An English language interface for constrained domains

    Science.gov (United States)

    Page, Brenda J.

    1989-01-01

    The Multi-Satellite Operations Control Center (MSOCC) Jargon Interpreter (MJI) demonstrates an English language interface for a constrained domain. A constrained domain is defined as one with a small and well delineated set of actions and objects. The set of actions chosen for the MJI is from the domain of MSOCC Applications Executive (MAE) Systems Test and Operations Language (STOL) directives and contains directives for signing a cathode ray tube (CRT) on or off, calling up or clearing a display page, starting or stopping a procedure, and controlling history recording. The set of objects chosen consists of CRTs, display pages, STOL procedures, and history files. Translation from English sentences to STOL directives is done in two phases. In the first phase, an augmented transition net (ATN) parser and dictionary are used for determining grammatically correct parsings of input sentences. In the second phase, grammatically typed sentences are submitted to a forward-chaining rule-based system for interpretation and translation into equivalent MAE STOL directives. Tests of the MJI show that it is able to translate individual clearly stated sentences into the subset of directives selected for the prototype. This approach to an English language interface may be used for similarly constrained situations by modifying the MJI's dictionary and rules to reflect the change of domain.

  1. Overlapping domain decomposition methods for elliptic quasi ...

    Indian Academy of Sciences (India)

    In this paper we provide a maximum norm analysis of an overlapping Schwarz method on non-matching grids for quasi-variational inequalities related to impulse control problem with mixed boundary conditions. We provide that the discretization on every sub-domain converges in uniform norm. Furthermore, a result of ...

  2. Overlapping domain decomposition methods for elliptic quasi ...

    Indian Academy of Sciences (India)

    Abstract. In this paper we provide a maximum norm analysis of an overlapping. Schwarz method on non-matching grids for quasi-variational inequalities related to impulse control problem with mixed boundary conditions. We provide that the dis- cretization on every sub-domain converges in uniform norm. Furthermore ...

  3. Supporting Collaborative Learning in the Architectural Domain

    NARCIS (Netherlands)

    Wolpers, Martin; Memmel, Martin; Giretti, Alberto; Casals, Miquel; Niemann, Katja; Specht, Marcus

    2013-01-01

    Wolpers, M., Memmel, M., Giretti, A., Casals, M., Niemann, K., & Specht, M. (2012). Supporting Collaborative Learning in the Architectural Domain. In A. Okada, T. Connolly, & P. Scott (Eds.), Collaborative Learning 2.0: Open Educational Resources (pp. 328-356). Hershey, PA: Information Science

  4. JavaScript domain-driven design

    CERN Document Server

    Fehre, Philipp

    2015-01-01

    If you are an experienced JavaScript developer who wants to improve the design of his or her applications, or find yourself in a situation to implement an application in an unfamiliar domain, this book is for you. Prior knowledge of JavaScript is required and prior experience with Node.js will also be helpful.

  5. Entanglement versus negative domains of Wigner functions

    DEFF Research Database (Denmark)

    Dahl, Jens Peder; Mack, H.; Wolf, A.

    2006-01-01

    We show that s waves, that is wave functions that only depend on a hyperradius, are entangled if and only if the corresponding Wigner functions exhibit negative domains. We illustrate this feature using a special class of s waves which allows us to perform the calculations analytically. This class...

  6. ISO 19512 : The land administration domain model

    NARCIS (Netherlands)

    Lemmen, C.H.J.; Van Oosterom, P.J.M.

    2011-01-01

    Focus of this paper is on the Land Administration Domain Model which is under development as an International Standard at ISO. This development is an initiative of the International Federation of Surveyors – FIG. The International Standard is expected to be published in 2012. Why is this development

  7. Promoting the Affective Domain within Online Education

    Science.gov (United States)

    Roche, Stephen H.

    2013-01-01

    In the past decade Higher Education Institutions have experienced tremendous growth in enrollments. To meet this demand, many higher education institutions have embraced online education and its requisite technologies. Online education has matured, and studies focusing on the cognitive domain indicate that distance education is as effective as the…

  8. Learning and Reasoning in Unknown Domains

    Science.gov (United States)

    Strannegård, Claes; Nizamani, Abdul Rahim; Juel, Jonas; Persson, Ulf

    2016-12-01

    In the story Alice in Wonderland, Alice fell down a rabbit hole and suddenly found herself in a strange world called Wonderland. Alice gradually developed knowledge about Wonderland by observing, learning, and reasoning. In this paper we present the system Alice In Wonderland that operates analogously. As a theoretical basis of the system, we define several basic concepts of logic in a generalized setting, including the notions of domain, proof, consistency, soundness, completeness, decidability, and compositionality. We also prove some basic theorems about those generalized notions. Then we model Wonderland as an arbitrary symbolic domain and Alice as a cognitive architecture that learns autonomously by observing random streams of facts from Wonderland. Alice is able to reason by means of computations that use bounded cognitive resources. Moreover, Alice develops her belief set by continuously forming, testing, and revising hypotheses. The system can learn a wide class of symbolic domains and challenge average human problem solvers in such domains as propositional logic and elementary arithmetic.

  9. Domain General Constraints on Statistical Learning

    Science.gov (United States)

    Thiessen, Erik D.

    2011-01-01

    All theories of language development suggest that learning is constrained. However, theories differ on whether these constraints arise from language-specific processes or have domain-general origins such as the characteristics of human perception and information processing. The current experiments explored constraints on statistical learning of…

  10. Memetic Algorithms, Domain Knowledge, and Financial Investing

    Science.gov (United States)

    Du, Jie

    2012-01-01

    While the question of how to use human knowledge to guide evolutionary search is long-recognized, much remains to be done to answer this question adequately. This dissertation aims to further answer this question by exploring the role of domain knowledge in evolutionary computation as applied to real-world, complex problems, such as financial…

  11. Nucleation of domains under the influence of temperature in ...

    Indian Academy of Sciences (India)

    the forward motion of the tips of the wedge-shaped domain as well as the lateral motion of the domain walls. However, there is no fresh nucleation of the domains. Generally, the nucleation of domain does not take place under the influence of temperature except under highly stressed conditions. However, in the ferroelectric.

  12. Estimation for Domains in Double Sampling with Probabilities ...

    African Journals Online (AJOL)

    Available publications show that the variance of an estimator of a domain parameter depends variance of the study variable for the domain elements and on the variance of the mean of that variable for element of the domain in each constituent stratum. In this article, we show that the variance of an estimator of a domain total ...

  13. Reflective measurement models, behavior domains, and common causes

    NARCIS (Netherlands)

    Markus, K.A.; Borsboom, D.

    Causal theories of measurement view test items as effects of a common cause. Behavior domain theories view test item responses as behaviors sampled from a common domain. A domain score is a composite score over this domain. The question arises whether latent variables can simultaneously constitute

  14. Domain-specific language design requires feature descriptions

    NARCIS (Netherlands)

    A. van Deursen (Arie); P. Klint (Paul)

    2001-01-01

    textabstractA domain-specific language (DSL) provides a notation tailored towards an application domain and is based on the relevant concepts and features of that domain. As such, a DSL is a means to describe and generate members of a family of programs in the domain. A prerequisite for the design

  15. Docking protein domains in contact space

    Directory of Open Access Journals (Sweden)

    Walker-Taylor Alice

    2006-06-01

    Full Text Available Abstract Background Many biological processes involve the physical interaction between protein domains. Understanding these functional associations requires knowledge of the molecular structure. Experimental investigations though present considerable difficulties and there is therefore a need for accurate and reliable computational methods. In this paper we present a novel method that seeks to dock protein domains using a contact map representation. Rather than providing a full three dimensional model of the complex, the method predicts contacting residues across the interface. We use a scoring function that combines structural, physicochemical and evolutionary information, where each potential residue contact is assigned a value according to the scoring function and the hypothesis is that the real configuration of contacts is the one that maximizes the score. The search is performed with a simulated annealing algorithm directly in contact space. Results We have tested the method on interacting domain pairs that are part of the same protein (intra-molecular domains. We show that it correctly predicts some contacts and that predicted residues tend to be significantly closer to each other than other pairs of residues in the same domains. Moreover we find that predicted contacts can often discriminate the best model (or the native structure, if present among a set of optimal solutions generated by a standard docking procedure. Conclusion Contact docking appears feasible and able to complement other computational methods for the prediction of protein-protein interactions. With respect to more standard docking algorithms it might be more suitable to handle protein conformational changes and to predict complexes starting from protein models.

  16. Characteristic impedance: frequency or time domain approach?

    Science.gov (United States)

    Qureshi, Muhammad Umar; Colebank, Mitchel; Schreier, David; Tabima Martinez, Diana Marcela; Haider, Mansoor A; Chesler, Naomi C; Olufsen, Mette S

    2017-11-27

    Characteristic impedance (Zc) is an important component in the theory of hemodynamics. It is a commonly used metric of proximal arterial stiffness and pulse wave velocity. Calculated using simultaneously measured dynamic pressure and flow data, estimates of Zc can be obtained using methods based on frequency or time domain analysis. Applications of these methods under different physiological and pathological conditions in species with different body sizes and heart rates show that the two approaches do not always yield the same result. Considering the interpretation and role of Zc as an important hemodynamic parameter, we have investigated the discrepancies between frequency and time domain estimates accounting for uncertainties associated with experimental processes and physiological conditions. We have used published data measured in different species including humans, dogs and mice, to investigate: (a) the effects of time delay and signal noise in the pressure-flow data, (b) uncertainties about the blood flow conditions, (c) and the periodicity of the cardiac cycle versus breathing cycle, on the frequency and time domain estimates of Zc, and (d) if discrepancies observed under different hemodynamic conditions can be eliminated. We have shown that the frequency and time domain estimates are not equally sensitive to certain characteristics of hemodynamic signals including phase lag between pressure and flow, signal to noise ratio and the end of systole retrograde flow. The discrepancies between two types of estimates are inherent due to their intrinsically different mathematical expressions and therefore it is impossible to define a criterion to resolve such discrepancies. We propose that the frequency and time domain estimates of Zc should be further assessed as two different hemodynamic parameters in a future study. © 2017 Institute of Physics and Engineering in Medicine.

  17. Interoperable Domain Models: the ISO Land Administration Domain Model Ladm and its External Classes

    Science.gov (United States)

    Lemmen, C. H. J.; van Oosterom, P. J. M.; Uitermark, H. T.; Zevenbergen, J. A.; Cooper, A. K.

    2011-08-01

    This paper provides a brief overview of one of the first spatial domain standards: a standard for the domain of Land Administration (LA). This standard is in the draft stage of development now (May 2011). The development of domain standards is a logical follow up after domain-independent standards, which are available now in the area of geo-information processing. The Land Administration Domain Model (LADM) provides a conceptual schema with three basic packages with a limited scope: parties, rights (and restrictions/responsibilities) and spatial units. Certain classes are outside the scope but can be referred to. An important aspect in the development of a coherent (Spatial) Information Infrastructures - (S)II is that the various standardized domain models are reusing the same model patterns as solutions for the same situations. In this paper the LADM and its external classes are briefly presented. It outlines the advantages of standardized domain models in the development of (S)II and the importance of LA as an authentic register, in relation to other authentic registers, such as for addresses, population, companies, topography, or buildings. This will be illustrated with the Dutch case of authentic registers.

  18. Domain adaptation of statistical machine translation with domain-focused web crawling.

    Science.gov (United States)

    Pecina, Pavel; Toral, Antonio; Papavassiliou, Vassilis; Prokopidis, Prokopis; Tamchyna, Aleš; Way, Andy; van Genabith, Josef

    In this paper, we tackle the problem of domain adaptation of statistical machine translation (SMT) by exploiting domain-specific data acquired by domain-focused crawling of text from the World Wide Web. We design and empirically evaluate a procedure for automatic acquisition of monolingual and parallel text and their exploitation for system training, tuning, and testing in a phrase-based SMT framework. We present a strategy for using such resources depending on their availability and quantity supported by results of a large-scale evaluation carried out for the domains of environment and labour legislation, two language pairs (English-French and English-Greek) and in both directions: into and from English. In general, machine translation systems trained and tuned on a general domain perform poorly on specific domains and we show that such systems can be adapted successfully by retuning model parameters using small amounts of parallel in-domain data, and may be further improved by using additional monolingual and parallel training data for adaptation of language and translation models. The average observed improvement in BLEU achieved is substantial at 15.30 points absolute.

  19. PTEN-PDZ domain interactions: binding of PTEN to PDZ domains of PTPN13.

    Science.gov (United States)

    Sotelo, Natalia S; Schepens, Jan T G; Valiente, Miguel; Hendriks, Wiljan J A J; Pulido, Rafael

    2015-05-01

    Protein modular interactions mediated by PDZ domains are essential for the establishment of functional protein networks controlling diverse cellular functions. The tumor suppressor PTEN possesses a C-terminal PDZ-binding motif (PDZ-BM) that is recognized by a specific set of PDZ domains from scaffolding and regulatory proteins. Here, we review the current knowledge on PTEN-PDZ domain interactions and tumor suppressor networks, describe methodology suitable to analyze these interactions, and report the binding of PTEN and the PDZ domain-containing protein tyrosine phosphatase PTPN13. Yeast two-hybrid and GST pull-down analyses showed that PTEN binds to PDZ2/PTPN13 domain in a manner that depends on the specific PTPN13 PDZ domain arrangement involving the interdomain region between PDZ1 and PDZ2. Furthermore, a specific binding profile of PTEN to PDZ2/PTPN13 domain was observed by mutational analysis of the PTEN PDZ-BM. Our results disclose a PDZ-mediated physical interaction of PTEN and PTPN13 with potential relevance in tumor suppression and cell homeostasis. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Revised domain structure of ulvan lyase and characterization of the first ulvan binding domain.

    Science.gov (United States)

    Melcher, Rebecca L J; Neumann, Marten; Fuenzalida Werner, Juan Pablo; Gröhn, Franziska; Moerschbacher, Bruno M

    2017-03-22

    Biomass waste products from green algae have recently been given new life, as these polysaccharides have potential applications in industry, agriculture, and medicine. One such polysaccharide group called ulvans displays many different, potentially useful properties that arise from their structural versatility. Hence, performing structural analyses on ulvan is crucial for future applications. However, chemical reaction-based analysis methods cannot fully characterize ulvan and tend to alter its structure. Thus, better methods require well-characterized ulvan-degrading enzymes. Therefore, we analysed a previously sequenced ulvan lyase (Genebank TM reference number JN104480) and characterized its domains. We suggest that the enzyme consists of a shorter than previously described catalytic domain, a newly identified substrate binding domain, and a C-terminal type 9 secretion system signal peptide. By separately expressing the two domains in E. coli, we confirmed that the binding domain is ulvan specific, having higher affinity for ulvan than most lectins for their ligands (affinity constant: 10 5  M -1 ). To our knowledge, this is the first description of an ulvan-binding domain. Overall, identifying this new binding domain is one step towards engineering ulvan enzymes that can be used to characterize ulvan, e.g. through enzymatic/mass spectrometric fingerprinting analyses, and help unlock its full potential.

  1. Individual globular domains and domain unfolding visualized in overstretched titin molecules with atomic force microscopy.

    Directory of Open Access Journals (Sweden)

    Zsolt Mártonfalvi

    Full Text Available Titin is a giant elastomeric protein responsible for the generation of passive muscle force. Mechanical force unfolds titin's globular domains, but the exact structure of the overstretched titin molecule is not known. Here we analyzed, by using high-resolution atomic force microscopy, the structure of titin molecules overstretched with receding meniscus. The axial contour of the molecules was interrupted by topographical gaps with a mean width of 27.7 nm that corresponds well to the length of an unfolded globular (immunoglobulin and fibronectin domain. The wide gap-width distribution suggests, however, that additional mechanisms such as partial domain unfolding and the unfolding of neighboring domain multimers may also be present. In the folded regions we resolved globules with an average spacing of 5.9 nm, which is consistent with a titin chain composed globular domains with extended interdomain linker regions. Topographical analysis allowed us to allocate the most distal unfolded titin region to the kinase domain, suggesting that this domain systematically unfolds when the molecule is exposed to overstretching forces. The observations support the prediction that upon the action of stretching forces the N-terminal ß-sheet of the titin kinase unfolds, thus exposing the enzyme's ATP-binding site and hence contributing to the molecule's mechanosensory function.

  2. Functional interchangeability of late domains, late domain cofactors and ubiquitin in viral budding.

    Directory of Open Access Journals (Sweden)

    Maria Zhadina

    2010-10-01

    Full Text Available The membrane scission event that separates nascent enveloped virions from host cell membranes often requires the ESCRT pathway, which can be engaged through the action of peptide motifs, termed late (L- domains, in viral proteins. Viral PTAP and YPDL-like L-domains bind directly to the ESCRT-I and ALIX components of the ESCRT pathway, while PPxY motifs bind Nedd4-like, HECT-domain containing, ubiquitin ligases (e.g. WWP1. It has been unclear precisely how ubiquitin ligase recruitment ultimately leads to particle release. Here, using a lysine-free viral Gag protein derived from the prototypic foamy virus (PFV, where attachment of ubiquitin to Gag can be controlled, we show that several different HECT domains can replace the WWP1 HECT domain in chimeric ubiquitin ligases and drive budding. Moreover, artificial recruitment of isolated HECT domains to Gag is sufficient to stimulate budding. Conversely, the HECT domain becomes dispensable if the other domains of WWP1 are directly fused to an ESCRT-1 protein. In each case where budding is driven by a HECT domain, its catalytic activity is essential, but Gag ubiquitination is dispensable, suggesting that ubiquitin ligation to trans-acting proteins drives budding. Paradoxically, however, we also demonstrate that direct fusion of a ubiquitin moiety to the C-terminus of PFV Gag can also promote budding, suggesting that ubiquitination of Gag can substitute for ubiquitination of trans-acting proteins. Depletion of Tsg101 and ALIX inhibits budding that is dependent on ubiquitin that is fused to Gag, or ligated to trans-acting proteins through the action of a PPxY motif. These studies underscore the flexibility in the ways that the ESCRT pathway can be engaged, and suggest a model in which the identity of the protein to which ubiquitin is attached is not critical for subsequent recruitment of ubiquitin-binding components of the ESCRT pathway and viral budding to proceed.

  3. A mixed finite element domain decomposition method for nearly elastic wave equations in the frequency domain

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xiaobing [Univ. of Tennessee, Knoxville, TN (United States)

    1996-12-31

    A non-overlapping domain decomposition iterative method is proposed and analyzed for mixed finite element methods for a sequence of noncoercive elliptic systems with radiation boundary conditions. These differential systems describe the motion of a nearly elastic solid in the frequency domain. The convergence of the iterative procedure is demonstrated and the rate of convergence is derived for the case when the domain is decomposed into subdomains in which each subdomain consists of an individual element associated with the mixed finite elements. The hybridization of mixed finite element methods plays a important role in the construction of the discrete procedure.

  4. Robust phase-domain transmission line representation based on time-domain fitting

    Energy Technology Data Exchange (ETDEWEB)

    Nobre, Diana M.; Neves, Washington L.A. [Federal University of Campina Grande (UFCG), Electrical Engineering Department, Av Aprigio Veloso, 882 Campina Grande, PB 58.109-970 (Brazil); Boaventura, Wallace do C. [Federal University of Minas Gerais (UFMG), Electrical Engineering Department, Av Antonio Carlos, 6627 Pampulha, Belo Horizonte, MG 31.270-010 (Brazil)

    2006-05-15

    This work presents a methodology for deriving a phase-domain transmission line representation based on time-domain fitting. A polynomial matrix in the discrete-time domain describes the resulting model. The robustness of the representation, its stability and passivity, is attained by imbedding a set of constraints in the solution of the fitting equations, which are solved using quadratic programming. Results demonstrating from transient simulations the features of the derived representation are presented for the case of an asymmetric, untransposed two-phase transmission line. (author)

  5. Ferroelectric charged domain walls in an applied electric field

    OpenAIRE

    Gureev, M. Y.; Mokry, P.; Tagantsev, A. K.; Setter, N.

    2012-01-01

    The interaction of electric field with charged domain walls in ferroelectrics is theoretically addressed. Ageneral expression for the force acting per unit area of a charged domain wall carrying free charge is derived. It is shown that, in proper ferroelectrics, the free charge carried by the wall is dependent on the size of the adjacent domains. As a result, the mobility of such domain wall (with respect to the applied field) is sensitive to the parameters of the domain pattern containing th...

  6. Serous carcinomatous component championed by heparin-binding EGF-like growth factor (HB-EGF) predisposing to metastasis and recurrence in stage I uterine malignant mixed mullerian tumor.

    Science.gov (United States)

    Zhang, Lei; Shimizu, David; Killeen, Jeffrey L; Honda, Stacey A; Lu, Di; Stanoyevitch, Alexander; Lin, Fritz; Wang, Beverly; Monuki, Edwin S; Carbone, Michele

    2016-07-01

    The stage I uterine malignant mixed mullerian tumor (MMMT) shows different potential for progression. We reason that MMMTs with high-grade carcinomatous component and positivity for HB-EGF are prone to recurrence/metastasis in the early stage. A retrospective clinical and histopathologic review with immunohistochemical staining for HB-EGF, EGFR, and integrin-α5 was performed for 62 surgically staged MMMT cases. Recurrence/metastasis (RM) is 6/18 (33%) in stage I disease. Of all the clinicopathologic variables and biomarkers analyzed for stage I MMMT, serous carcinomatous component (83% [5/6] versus 17% [1/12], P = .0015) and HB-EGF expression (100% [6/6] versus 50% [6/12], P=.0339) were significantly different between groups with RM and without RM. The presence of serous carcinoma in all stages was 83% (5/6) in stage I with RM, 8% (1/12) in stage I without RM, 20% (1/5) in stage II, 36.4% (8/22) in stage III and 64.7% (11/17) in stage IV; this was paralleled by HB-EGF expression of 100% (6/6), 50% (6/12), 40% (2/5), 50% (11/22) and 71% (12/17) with a correlation coefficient r=0.9131 (P=.027). HB-EGF and integrin-α5 were highly expressed in MMMTs bearing serous carcinoma component, compared to endometrioid and unclassifiable/miscellaneous subtypes (84.6%/47.6%/33.3%, P=.025 for HB-EGF; and 61.5%/42.9%/20.0%, P=.021 for integrin-α5). The EGFR positivity was comparable among the three subtypes (48.1%, 47.6% and 26.7%, P=.326). This study indicates that serous carcinomatous component championed by expression of HB-EGF predisposes to recurrence/metastasis in stage I MMMT. This process might involve integrin-α5 and does not seem to require overexpression of EGFR. Further study is required. Published by Elsevier Inc.

  7. Heparin-binding EGF-like growth factor, which acts as the diphtheria toxin receptor, forms a complex with membrane protein DRAP27/CD9, which up-regulates functional receptors and diphtheria toxin sensitivity.

    OpenAIRE

    Iwamoto, R; Higashiyama, S.; Mitamura, T; Taniguchi, N.; Klagsbrun, M; Mekada, E

    1994-01-01

    DRAP27, the monkey homolog of human CD9 antigen (DRAP27/CD9) and diphtheria toxin receptor (DTR) were expressed in mouse L cells. L cells transfected transiently with both DRAP27/CD9 and DTR cDNA bound approximately 10 times more diphtheria toxin (DT) than cells transfected with DTR alone. Stable L cell transfectants expressing both DTR and DRAP27/CD9 (LCH-1 cells) had 15 times more cell surface DT-binding sites and were 20 times more sensitive to DT than were stable L cell transfectants expr...

  8. Semi-Supervised Single- and Multi-Domain Regression with Multi-Domain Training

    CERN Document Server

    Michaeli, Tomer; Sapiro, Guillermo

    2012-01-01

    We address the problems of multi-domain and single-domain regression based on distinct and unpaired labeled training sets for each of the domains and a large unlabeled training set from all domains. We formulate these problems as a Bayesian estimation with partial knowledge of statistical relations. We propose a worst-case design strategy and study the resulting estimators. Our analysis explicitly accounts for the cardinality of the labeled sets and includes the special cases in which one of the labeled sets is very large or, in the other extreme, completely missing. We demonstrate our estimators in the context of removing expressions from facial images and in the context of audio-visual word recognition, and provide comparisons to several recently proposed multi-modal learning algorithms.

  9. Genome-wide identification and domain organization of lectin domains in cucumber.

    Science.gov (United States)

    Dang, Liuyi; Van Damme, Els J M

    2016-11-01

    Lectins are ubiquitous proteins in plants and play important roles in a diverse set of biological processes, such as plant defense and cell signaling. Despite the availability of the Cucumis sativus L. genome sequence since 2009, little is known with respect to the occurrence of lectins in cucumber. In this study, a total of 146 putative lectin genes belonging to 10 different lectin families were identified and localized in the cucumber genome. Domain architecture analysis revealed that most of these lectin gene sequences contain multiple domains, where lectin domains are linked with other domains, as such creating chimeric lectin sequences encoding proteins with dual activities. This study provides an overview of lectin motifs in cucumber and will help to understand their potential biological role(s). Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Domain Walls and Matter-Antimatter Domains in the Early Universe

    National Research Council Canada - National Science Library

    Dolgov A.D; Godunov S.I; Rudenko A.S

    2017-01-01

    We suggest a scenario of spontaneous (or dynamical) C and CP violation according to which it is possible to generate domains of matter and antimatter separated by cosmologically large distances. Such C(CP...

  11. A Fast, Efficient Domain Adaptation Technique for Cross-Domain Electroencephalography(EEG)-Based Emotion Recognition.

    Science.gov (United States)

    Chai, Xin; Wang, Qisong; Zhao, Yongping; Li, Yongqiang; Liu, Dan; Liu, Xin; Bai, Ou

    2017-05-03

    Electroencephalography (EEG)-based emotion recognition is an important element in psychiatric health diagnosis for patients. However, the underlying EEG sensor signals are always non-stationary if they are sampled from different experimental sessions or subjects. This results in the deterioration of the classification performance. Domain adaptation methods offer an effective way to reduce the discrepancy of marginal distribution. However, for EEG sensor signals, both marginal and conditional distributions may be mismatched. In addition, the existing domain adaptation strategies always require a high level of additional computation. To address this problem, a novel strategy named adaptive subspace feature matching (ASFM) is proposed in this paper in order to integrate both the marginal and conditional distributions within a unified framework (without any labeled samples from target subjects). Specifically, we develop a linear transformation function which matches the marginal distributions of the source and target subspaces without a regularization term. This significantly decreases the time complexity of our domain adaptation procedure. As a result, both marginal and conditional distribution discrepancies between the source domain and unlabeled target domain can be reduced, and logistic regression (LR) can be applied to the new source domain in order to train a classifier for use in the target domain, since the aligned source domain follows a distribution which is similar to that of the target domain. We compare our ASFM method with six typical approaches using a public EEG dataset with three affective states: positive, neutral, and negative. Both offline and online evaluations were performed. The subject-to-subject offline experimental results demonstrate that our component achieves a mean accuracy and standard deviation of 80.46% and 6.84%, respectively, as compared with a state-of-the-art method, the subspace alignment auto-encoder (SAAE), which achieves values

  12. Quantifying information transfer by protein domains: analysis of the Fyn SH2 domain structure.

    Science.gov (United States)

    Lenaerts, Tom; Ferkinghoff-Borg, Jesper; Stricher, Francois; Serrano, Luis; Schymkowitz, Joost W H; Rousseau, Frederic

    2008-10-08

    Efficient communication between distant sites within a protein is essential for cooperative biological response. Although often associated with large allosteric movements, more subtle changes in protein dynamics can also induce long-range correlations. However, an appropriate formalism that directly relates protein structural dynamics to information exchange between functional sites is still lacking. Here we introduce a method to analyze protein dynamics within the framework of information theory and show that signal transduction within proteins can be considered as a particular instance of communication over a noisy channel. In particular, we analyze the conformational correlations between protein residues and apply the concept of mutual information to quantify information exchange. Mapping out changes of mutual information on the protein structure then allows visualizing how distal communication is achieved. We illustrate the approach by analyzing information transfer by the SH2 domain of Fyn tyrosine kinase, obtained from Monte Carlo dynamics simulations. Our analysis reveals that the Fyn SH2 domain forms a noisy communication channel that couples residues located in the phosphopeptide and specificity binding sites and a number of residues at the other side of the domain near the linkers that connect the SH2 domain to the SH3 and kinase domains. We find that for this particular domain, communication is affected by a series of contiguous residues that connect distal sites by crossing the core of the SH2 domain. As a result, our method provides a means to directly map the exchange of biological information on the structure of protein domains, making it clear how binding triggers conformational changes in the protein structure. As such it provides a structural road, next to the existing attempts at sequence level, to predict long-range interactions within protein structures.

  13. Thermal Loss of High-Q Antennas in Time Domain vs. Frequency Domain Solver

    DEFF Research Database (Denmark)

    Bahramzy, Pevand; Pedersen, Gert Frølund

    2014-01-01

    High-Q structures pose great challenges to their loss simulations in Time Domain Solvers (TDS). Therefore, in this work the thermal loss of high-Q antennas is calculated both in TDS and Frequency Domain Solver (FDS), which are then compared with each other and with the actual measurements....... The thermal loss calculation in FDS is shown to be more accurate for high-Q antennas....

  14. Creating and Manipulating a Domain-Specific Formal Object Base to Support a Domain-Oriented Application Composition System

    Science.gov (United States)

    1992-12-01

    and add new attributes as needed (11:129). 2.2.3.2 Feature Oriented Domain Analysis In their Feature-Oriented Domain Analysis ( FODA ) study, the...problems within the domain 3. Architecture Modeling - Create software architecture(s) to implement a solution in the problem domain. The FODA study also...dissertation, The University of Texas at Austin, Austin Texas, 1990. 12. Kang, Kyo C. and others. Feature-Oriented Domain Analysis ( FODA ) Feasibil- ity Study

  15. Domain Theory, Its Models and Concepts

    DEFF Research Database (Denmark)

    Andreasen, Mogens Myrup; Howard, Thomas J.; Bruun, Hans Peter Lomholt

    2014-01-01

    , which can support design work and to form elements of designers’ mindsets and thereby their practice. The theory is a model-based theory, which means it is composed of concepts and models, which explains certain design phenomena. Many similar theories are described in the literature with differences...... and industrial applications especially for the DFX areas (not reported here) and for product modelling. The theory therefore contains a rich ontology of interrelated concepts. The Domain Theory is not aiming to create normative methods but the creation of a collection of concepts related to design phenomena...... in the set of concepts but assumingly all valid. The Domain Theory cannot be falsified or proven; but its value may be seen spanning from its range and productivity as described in the article....

  16. Manifest domains:analysis and description

    DEFF Research Database (Denmark)

    Bjørner, Dines

    2017-01-01

    show how to model attributes, essentially following Michael Jackson (Software requirements & specifications: a lexicon of practice, principles and prejudices. ACM Press, Addison-Wesley, Reading, 1995), but with a twist: The attribute model introduces the attribute analysis prompts is...... parts, and attributes. We show that the manifest domain analysis endeavour can be supported by a calculus of manifest domain analysis prompts: is_entity, is_endurant, is_perdurant, is_part, is_component, is_material, is_atomic, is_composite, has_components, has_materials, has_concrete_type, attribute...... processes. C.A.R. Hoare series in computer science. Prentice-Hall International, London, 2004). We show how to model essential aspects of perdurants in terms of their signatures based on the concepts of endurants. And we show how one can “compile” descriptions of endurant parts into descriptions...

  17. Damping Estimation by Frequency Domain Decomposition

    DEFF Research Database (Denmark)

    Brincker, Rune; Ventura, C. E.; Andersen, P.

    2001-01-01

    In this paper it is explained how the damping can be estimated using the Frequency Domain Decomposition technique for output-only modal identification, i.e. in the case where the modal parameters is to be estimated without knowing the forces exciting the system. Also it is explained how the natural...... back to time domain to identify damping and frequency. The technique is illustrated on a simple simulation case with 2 closely spaced modes. On this example it is illustrated how the identification is influenced by very closely spacing, by non-orthogonal modes, and by correlated input. The technique...... is further illustrated on the output-only identification of the Great Belt Bridge. On this example it is shown how the damping is identified on a weakly exited mode and a closely spaced mode....

  18. Multiple Shooting and Time Domain Decomposition Methods

    CERN Document Server

    Geiger, Michael; Körkel, Stefan; Rannacher, Rolf

    2015-01-01

    This book offers a comprehensive collection of the most advanced numerical techniques for the efficient and effective solution of simulation and optimization problems governed by systems of time-dependent differential equations. The contributions present various approaches to time domain decomposition, focusing on multiple shooting and parareal algorithms.  The range of topics covers theoretical analysis of the methods, as well as their algorithmic formulation and guidelines for practical implementation. Selected examples show that the discussed approaches are mandatory for the solution of challenging practical problems. The practicability and efficiency of the presented methods is illustrated by several case studies from fluid dynamics, data compression, image processing and computational biology, giving rise to possible new research topics.  This volume, resulting from the workshop Multiple Shooting and Time Domain Decomposition Methods, held in Heidelberg in May 2013, will be of great interest to applied...

  19. Temporal Annotation in the Clinical Domain

    Science.gov (United States)

    Styler, William F.; Bethard, Steven; Finan, Sean; Palmer, Martha; Pradhan, Sameer; de Groen, Piet C; Erickson, Brad; Miller, Timothy; Lin, Chen; Savova, Guergana; Pustejovsky, James

    2014-01-01

    This article discusses the requirements of a formal specification for the annotation of temporal information in clinical narratives. We discuss the implementation and extension of ISO-TimeML for annotating a corpus of clinical notes, known as the THYME corpus. To reflect the information task and the heavily inference-based reasoning demands in the domain, a new annotation guideline has been developed, “the THYME Guidelines to ISO-TimeML (THYME-TimeML)”. To clarify what relations merit annotation, we distinguish between linguistically-derived and inferentially-derived temporal orderings in the text. We also apply a top performing TempEval 2013 system against this new resource to measure the difficulty of adapting systems to the clinical domain. The corpus is available to the community and has been proposed for use in a SemEval 2015 task. PMID:29082229

  20. LHC RF System Time-Domain Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Mastorides, T.; Rivetta, C.; /SLAC

    2010-09-14

    Non-linear time-domain simulations have been developed for the Positron-Electron Project (PEP-II) and the Large Hadron Collider (LHC). These simulations capture the dynamic behavior of the RF station-beam interaction and are structured to reproduce the technical characteristics of the system (noise contributions, non-linear elements, and more). As such, they provide useful results and insight for the development and design of future LLRF feedback systems. They are also a valuable tool for the study of diverse longitudinal beam dynamics effects such as coupled-bunch impedance driven instabilities and single bunch longitudinal emittance growth. Results from these studies and related measurements from PEP-II and LHC have been presented in multiple places. This report presents an example of the time-domain simulation implementation for the LHC.

  1. Transposition of Domain Knowledge into Educational Games

    DEFF Research Database (Denmark)

    Marchetti, Emanuela; Jensen, Kristoffer; Valente, Andrea

    2014-01-01

    Starting from Rogoff’s (1990) theory of apprenticeship in thinking and Apter’s (1987) reversal theory, this paper discusses the formulation of PlayDT (Playful Domain Transposition), a new approach to support the transposition of complex concepts, from different knowledge domains, into playful...... a participatory design process, involving task-supported interviews and co-design workshops with children between 9 and 12. Among the findings, a strategy to map knowledge into interactions emerged, together with rich insights about children’s different approaches to play. In an attempt to evaluate the knowledge...... of the PlayDT approach, through another design study, aimed at creating a game to support learning of the Fourier Transform. In order to generalize further the mapping approach, a participatory workshop was conducted with university students, who provided inspirations to map the Fourier Transform...

  2. Space Domain Awareness for Manned GEO Servicing

    Science.gov (United States)

    Blake, T.

    2010-09-01

    The Defense Advanced Research Projects Agency (DARPA) is embarking on a joint program to service spacecraft in Geosynchronous (GEO) Orbit. This ambitious program, known as R5 (Rendezvous, Refuel, Refurbish, Repair, and Reposition), will develop the technologies required to extend the life of billions of dollars of invested in building, launching and operating GEO spacecraft. Inherent in the R5 program, is the need for high quality awareness of the space domain at GEO. Servicing non-operational spacecraft in GEO will require enhanced debris detect/track and space weather monitoring for crew safety, as well as high resolution characterization of the spacecraft to understand the status of the spacecraft to manifest the repair mission. This paper will briefly describe the GEO space domain sensor and data processing requirements to support the R5 program and outline DARPA’s program plans to develop these capabilities. Distribution Statement A (Approved for Public Release, Distribution Unlimited). DISTAR case 15410.

  3. Modeling Network Traffic in Wavelet Domain

    Directory of Open Access Journals (Sweden)

    Sheng Ma

    2004-12-01

    Full Text Available This work discovers that although network traffic has the complicated short- and long-range temporal dependence, the corresponding wavelet coefficients are no longer long-range dependent. Therefore, a "short-range" dependent process can be used to model network traffic in the wavelet domain. Both independent and Markov models are investigated. Theoretical analysis shows that the independent wavelet model is sufficiently accurate in terms of the buffer overflow probability for Fractional Gaussian Noise traffic. Any model, which captures additional correlations in the wavelet domain, only improves the performance marginally. The independent wavelet model is then used as a unified approach to model network traffic including VBR MPEG video and Ethernet data. The computational complexity is O(N for developing such wavelet models and generating synthesized traffic of length N, which is among the lowest attained.

  4. Broadband Beamspace DOA Estimation: Frequency-Domain and Time-Domain Processing Approaches

    Directory of Open Access Journals (Sweden)

    Yan Shefeng

    2007-01-01

    Full Text Available Frequency-domain and time-domain processing approaches to direction-of-arrival (DOA estimation for multiple broadband far field signals using beamspace preprocessing structures are proposed. The technique is based on constant mainlobe response beamforming. A set of frequency-domain and time-domain beamformers with constant (frequency independent mainlobe response and controlled sidelobes is designed to cover the spatial sector of interest using optimal array pattern synthesis technique and optimal FIR filters design technique. These techniques lead the resulting beampatterns higher mainlobe approximation accuracy and yet lower sidelobes. For the scenario of strong out-of-sector interfering sources, our approaches can form nulls or notches in the direction of them and yet guarantee that the mainlobe response of the beamformers is constant over the design band. Numerical results show that the proposed time-domain processing DOA estimator has comparable performance with the proposed frequency-domain processing method, and that both of them are able to resolve correlated source signals and provide better resolution at lower signal-to-noise ratio (SNR and lower root-mean-square error (RMSE of the DOA estimate compared with the existing method. Our beamspace DOA estimators maintain good DOA estimation and spatial resolution capability in the scenario of strong out-of-sector interfering sources.

  5. Maritime Domain Awareness FY08 assessment report

    OpenAIRE

    MacKinnon, Douglas J.; Schacher, Gordon E.; Hutchins, Susan G.; Freeman, Jared

    2008-01-01

    The U.S. Navy has been given the responsibility to develop a comprehensive, worldwide Maritime Domain Awareness (MDA) capability. PEO C4I has specified and assessed an initial set of systems, designated Spiral-1, to support MDS. Deputy Under Secretary of the Navy (DUSN) has appointed the Naval Postgraduate School (NPS) to assess the overall capabilities and needs of MDA. This document reports the progress made in developing MDA capabilities during FY08. It summarizes information from PEO C4...

  6. Tyrosine Phosphorylation of Botulinum Neurotoxin Protease Domains

    OpenAIRE

    Stephen eToth; Ernst E Brueggemann; Oyler, George A.; Smith, Leonard A.; Hines, Harry B.; S. Ashraf eAhmed

    2012-01-01

    Botulinum neurotoxins are most potent of all toxins. Their N-terminal light chain domain (Lc) translocates into peripheral cholinergic neurons to exert its endoproteolytic action leading to muscle paralysis. Therapeutic development against these toxins is a major challenge due to their in vitro and in vivo structural differences. Although three-dimensional structures and reaction mechanisms are very similar, the seven serotypes designated A through G vastly vary in their intracellular catalyt...

  7. Domain decomposition methods for mortar finite elements

    Energy Technology Data Exchange (ETDEWEB)

    Widlund, O.

    1996-12-31

    In the last few years, domain decomposition methods, previously developed and tested for standard finite element methods and elliptic problems, have been extended and modified to work for mortar and other nonconforming finite element methods. A survey will be given of work carried out jointly with Yves Achdou, Mario Casarin, Maksymilian Dryja and Yvon Maday. Results on the p- and h-p-version finite elements will also be discussed.

  8. Image domain propeller fast spin echo.

    Science.gov (United States)

    Skare, Stefan; Holdsworth, Samantha J; Lilja, Anders; Bammer, Roland

    2013-04-01

    A new pulse sequence for high-resolution T2-weighted (T2-w) imaging is proposed - image domain propeller fast spin echo (iProp-FSE). Similar to the T2-w PROPELLER sequence, iProp-FSE acquires data in a segmented fashion, as blades that are acquired in multiple TRs. However, the iProp-FSE blades are formed in the image domain instead of in the k-space domain. Each iProp-FSE blade resembles a single-shot fast spin echo (SSFSE) sequence with a very narrow phase-encoding field of view (FOV), after which N rotated blade replicas yield the final full circular FOV. Our method of combining the image domain blade data to a full FOV image is detailed, and optimal choices of phase-encoding FOVs and receiver bandwidths were evaluated on phantom and volunteers. The results suggest that a phase FOV of 15-20%, a receiver bandwidth of ±32-63 kHz and a subsequent readout time of about 300 ms provide a good tradeoff between signal-to-noise ratio (SNR) efficiency and T2 blurring. Comparisons between iProp-FSE, Cartesian FSE and PROPELLER were made on single-slice axial brain data, showing similar T2-w tissue contrast and SNR with great anatomical conspicuity at similar scan times - without colored noise or streaks from motion. A new slice interleaving order is also proposed to improve the multislice capabilities of iProp-FSE. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. On fictitious domain formulations for Maxwell's equations

    DEFF Research Database (Denmark)

    Dahmen, W.; Jensen, Torben Klint; Urban, K.

    2003-01-01

    We consider fictitious domain-Lagrange multiplier formulations for variational problems in the space H(curl: Omega) derived from Maxwell's equations. Boundary conditions and the divergence constraint are imposed weakly by using Lagrange multipliers. Both the time dependent and time harmonic...... formulations of the Maxwell's equations are considered. and we derive well-posed formulations for both cases. The variational problem that arises can be discretized by functions that do not satisfy an a-priori divergence constraint....

  10. Differential operators in exterior domain and application

    OpenAIRE

    Shakhmurov, Veli

    2017-01-01

    The abstract elliptic and parabolic equations on exterior domain are considered. The equations have top-order variable coefficients. The separability properties of boundary value problems for elliptic equation and well-posedness of the Cauchy problem for parabolic equations are established. In application, the well-posedness of Wentzell-Robin type mixed probem for parabolic equation, Cauchy problem for anisotropic parabolic equations and system of parabolic equations are derived

  11. 2015 Cross-Domain Deterrence Seminar Bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Juarez, Anthony [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-02-04

    In November 2015, the Center for Global Security Research, NSO, and Global Security program jointly sponsored a seminar investigating questions related to cross-domain deterrence at Lawrence Livermore National Laboratory. At the seminar, experts were asked to moderate discussion based on the four topics below. For each of these topics, we have compiled a short list of literature that will help analysts develop a baseline understanding of the issue.

  12. Finite Temperature Qcd With Domain Wall Fermions

    CERN Document Server

    Fleming, G T

    2001-01-01

    Domain wall fermions are a new lattice fermion formulation which preserves the full chiral symmetry of the continuum at finite lattice spacing, up to terms exponentially small in an extra parameter. We discuss the main features of the formulation and its application to study of QCD with two light fermions of equal mass. We also present numerical studies of the two flavor QCD thermodynamics with aT = 1/4.

  13. Allosteric Communication in the Dynein Motor Domain

    Science.gov (United States)

    Bhabha, Gira; Cheng, Hui-Chun; Zhang, Nan; Moeller, Arne; Liao, Maofu; Speir, Jeffrey A.; Cheng, Yifan; Vale, Ronald D.

    2014-01-01

    SUMMARY Dyneins power microtubule motility using ring-shaped, AAA-containing motor domains. Here, we report X-ray and electron microscopy (EM) structures of yeast dynein bound to different ATP analogs, which collectively provide insight into the roles of dynein’s two major ATPase sites, AAA1 and AAA3, in the conformational change mechanism. ATP binding to AAA1 triggers a cascade of conformational changes that propagate to all six AAA domains and cause a large movement of the “linker,” dynein’s mechanical element. In contrast to the role of AAA1 in driving motility, nucleotide transitions in AAA3 gate the transmission of conformational changes between AAA1 and the linker, suggesting that AAA3 acts as a regulatory switch. Further structural and mutational studies also uncover a role for the linker in regulating the catalytic cycle of AAA1. Together, these results reveal how dynein’s two major ATP-binding sites initiate and modulate conformational changes in the motor domain during motility. PMID:25417161

  14. Productivity? Domain Complexity vs. Tacit Knowledge

    DEFF Research Database (Denmark)

    Madsen, Erik Skov; Mikkelsen, Lars Lindegaard

    This paper discusses productivity in relation to tacit knowledge (which in the paper is regarded as skills, experiences, competences and attitudes) and domain complexity. The study is based on five very different case studies; three studies are conducted in Den¬mark, China, and the Czech Republic...... a novel conceptual framework around which manage¬ment will be able to generate discussions about productivity and the need for learning programs when considering changes in the complexity of a domain.......This paper discusses productivity in relation to tacit knowledge (which in the paper is regarded as skills, experiences, competences and attitudes) and domain complexity. The study is based on five very different case studies; three studies are conducted in Den¬mark, China, and the Czech Republic...... and these studies are particularly studying knowledge transfer when moving manufacturing facilities to a new location. Two studies investigate operation and automation of oil and gas production in the North Sea. Semi-structured interviews, surveys, and observations are the main methods used. The paper provides...

  15. Bregmanized Domain Decomposition for Image Restoration

    KAUST Repository

    Langer, Andreas

    2012-05-22

    Computational problems of large-scale data are gaining attention recently due to better hardware and hence, higher dimensionality of images and data sets acquired in applications. In the last couple of years non-smooth minimization problems such as total variation minimization became increasingly important for the solution of these tasks. While being favorable due to the improved enhancement of images compared to smooth imaging approaches, non-smooth minimization problems typically scale badly with the dimension of the data. Hence, for large imaging problems solved by total variation minimization domain decomposition algorithms have been proposed, aiming to split one large problem into N > 1 smaller problems which can be solved on parallel CPUs. The N subproblems constitute constrained minimization problems, where the constraint enforces the support of the minimizer to be the respective subdomain. In this paper we discuss a fast computational algorithm to solve domain decomposition for total variation minimization. In particular, we accelerate the computation of the subproblems by nested Bregman iterations. We propose a Bregmanized Operator Splitting-Split Bregman (BOS-SB) algorithm, which enforces the restriction onto the respective subdomain by a Bregman iteration that is subsequently solved by a Split Bregman strategy. The computational performance of this new approach is discussed for its application to image inpainting and image deblurring. It turns out that the proposed new solution technique is up to three times faster than the iterative algorithm currently used in domain decomposition methods for total variation minimization. © Springer Science+Business Media, LLC 2012.

  16. Detecting coevolution in and among protein domains.

    Directory of Open Access Journals (Sweden)

    Chen-Hsiang Yeang

    2007-11-01

    Full Text Available Correlated changes of nucleic or amino acids have provided strong information about the structures and interactions of molecules. Despite the rich literature in coevolutionary sequence analysis, previous methods often have to trade off between generality, simplicity, phylogenetic information, and specific knowledge about interactions. Furthermore, despite the evidence of coevolution in selected protein families, a comprehensive screening of coevolution among all protein domains is still lacking. We propose an augmented continuous-time Markov process model for sequence coevolution. The model can handle different types of interactions, incorporate phylogenetic information and sequence substitution, has only one extra free parameter, and requires no knowledge about interaction rules. We employ this model to large-scale screenings on the entire protein domain database (Pfam. Strikingly, with 0.1 trillion tests executed, the majority of the inferred coevolving protein domains are functionally related, and the coevolving amino acid residues are spatially coupled. Moreover, many of the coevolving positions are located at functionally important sites of proteins/protein complexes, such as the subunit linkers of superoxide dismutase, the tRNA binding sites of ribosomes, the DNA binding region of RNA polymerase, and the active and ligand binding sites of various enzymes. The results suggest sequence coevolution manifests structural and functional constraints of proteins. The intricate relations between sequence coevolution and various selective constraints are worth pursuing at a deeper level.

  17. PID position domain control for contour tracking

    Science.gov (United States)

    Ouyang, P. R.; Pano, V.; Dam, T.

    2015-01-01

    Contour error reduction for modern machining processes is an important concern in multi-axis contour tracking applications in order to ensure the quality of final products. Many control methods were developed in time domain to deal with contour tracking problems, and a proportional-derivative (PD) position domain control (PDC) was also proposed by the authors. It is well known that proportional-integral-differential (PID) control is the most popular control in applications of control theory. In this paper, a PID PDC is proposed for reducing contour tracking errors and improving contour tracking performances. To determine proper control gains, system stability analysis is conducted for the proposed PDC. Several experiments are conducted to evaluate the performance of the developed approach and are compared with the PID time domain control (TDC) and the cross-coupled control. Different control gains are used in the simulations to explore the robustness of PID PDC. Comparison results demonstrate the effectiveness and good contour performances of PID PDC for contour tracking applications.

  18. Metastable magnetic domain walls in cylindrical nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, C.A.; MacLaren, D.A.; McVitie, S., E-mail: Stephen.McVitie@glasgow.ac.uk

    2015-05-01

    The stability of the asymmetric domain wall (ATDW) in soft magnetic cylindrical nanowires and nanotubes is investigated using micromagnetic simulations. Our calculated phase diagram shows that for cylindrical permalloy nanowires, the transverse domain wall (TDW) is the ground state for radii below 20 nm whilst the Bloch point wall (BPW) is favoured in thicker wires. The ATDW stabilises only as a metastable state but with energy close to that of the BPW. Characterisation of the DW spin structures reveals that the ATDW has a vortex-like surface spin state, in contrast to the divergent surface spins of the TDW. This results in lowering of surface charge above the critical radius. For both cylindrical nanotubes and nanowires we find that ATDWs only appear to exist as metastable static states and are particularly suppressed in nanotubes due to an increase in magnetostatic energy. - Highlights: • We simulate the micromagnetic structures of domain walls in cylindrical nanowires. • A phase diagram identifies ground and metastable states. • Asymmetric transverse walls are metastable in nanowires but suppressed in tubes. • Unrolling surface magnetisation aids visualisation of asymmetry and chirality. • We predict experimental discrimination based on magnetic charge distribution.

  19. Fast domain wall dynamics in amorphous and nanocrystalline magnetic microwires

    Energy Technology Data Exchange (ETDEWEB)

    Varga, R., E-mail: rvarga@upjs.sk [Institute of Physics, Faculty of Science, UPJS, Park Angelinum 9, 041 54, Kosice (Slovakia); Klein, P.; Richter, K. [Institute of Physics, Faculty of Science, UPJS, Park Angelinum 9, 041 54, Kosice (Slovakia); Zhukov, A. [Dept. Fisica de Materiales, Fac. Quimica, UPV/EHU, San Sebastian (Spain); Vazquez, M. [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Ines de la Cruz 3, 28049 Cantoblanco, Madrid (Spain)

    2012-10-15

    We have studied the effect of thermal treatment on the domain wall dynamics of FeSiB and FeCoMoB microwires. It was shown that annealing in transversal magnetic field increases the domain wall mobility as well as the domain wall velocity. Annealing under the tensile stress hinders the appearance of the monodomain structure but application of tensile stress leads to the magnetic bistability having the domain wall mobility twice higher that in as-cast state. Further increase of the tensile stress reduces the domain wall mobility but the domain wall velocity increases as a result of the decrease of critical propagation field. Annealing of the FeCoMoB microwire by Joule heating leads to introduction of the circular anisotropy that favors the vortex domain wall. Such treatment increases the domain wall mobility as well as the maximum domain wall velocity.

  20. PREFACE: Domain wall dynamics in nanostructures Domain wall dynamics in nanostructures

    Science.gov (United States)

    Marrows, C. H.; Meier, G.

    2012-01-01

    Domain structures in magnetic materials are ubiquitous and have been studied for decades. The walls that separate them are topological defects in the magnetic order parameter and have a wide variety of complex forms. In general, their investigation is difficult in bulk materials since only the domain structure on the surface of a specimen is visible. Cutting the sample to reveal the interior causes a rearrangement of the domains into a new form. As with many other areas of magnetism, the study of domain wall physics has been revitalised by the advent of nanotechnology. The ability to fabricate nanoscale structures has permitted the formation of simplified and controlled domain patterns; the development of advanced microscopy methods has permitted them to be imaged and then modelled; subjecting them to ultrashort field and current pulses has permitted their dynamics to be explored. The latest results from all of these advances are described in this special issue. Not only has this led to results of great scientific beauty, but also to concepts of great applicability to future information technologies. In this issue the reader will find the latest results for these domain wall dynamics and the high-speed processes of topological structures such as domain walls and magnetic vortices. These dynamics can be driven by the application of magnetic fields, or by flowing currents through spintronic devices using the novel physics of spin-transfer torque. This complexity has been studied using a wide variety of experimental techniques at the edge of the spatial and temporal resolution currently available, and can be described using sophisticated analytical theory and computational modelling. As a result, the dynamics can be engineered to give rise to finely controlled memory and logic devices with new functionality. Moreover, the field is moving to study not only the conventional transition metal ferromagnets, but also complex heterostructures, novel magnets and even other

  1. Time Domain Diffraction by Composite Structures

    Science.gov (United States)

    Riccio, Giovanni; Frongillo, Marcello

    2017-04-01

    Time domain (TD) diffraction problems are receiving great attention because of the widespread use of ultra wide band (UWB) communication and radar systems. It is commonly accepted that, due to the large bandwidth of the UWB signals, the analysis of the wave propagation mechanisms in the TD framework is preferable to the frequency domain (FD) data processing. Furthermore, the analysis of transient scattering phenomena is also of importance for predicting the effects of electromagnetic pulses on civil structures. Diffraction in the TD framework represents a challenging problem and numerical discretization techniques can be used to support research and industry activities. Unfortunately, these methods become rapidly intractable when considering excitation pulses with high frequency content. This contribution deals with the TD diffraction phenomenon related to composite structures containing a dielectric wedge with arbitrary apex angle when illuminated by a plane wave. The approach is the same used in [1]-[3]. The transient diffracted field originated by an arbitrary function plane wave is evaluated via a convolution integral involving the TD diffraction coefficients, which are determined in closed form starting from the knowledge of the corresponding FD counterparts. In particular, the inverse Laplace transform is applied to the FD Uniform Asymptotic Physical Optics (FD-UAPO) diffraction coefficients available for the internal region of the structure and the surrounding space. For each observation domain, the FD-UAPO expressions are obtained by considering electric and magnetic equivalent PO surface currents located on the interfaces. The surface radiation integrals using these sources is assumed as starting point and manipulated for obtaining integrals able to be solved by means of the Steepest Descent Method and the Multiplicative Method. [1] G. Gennarelli and G. Riccio, "Time domain diffraction by a right-angled penetrable wedge," IEEE Trans. Antennas Propag., Vol

  2. Role of Kallistatin Treatment in Aging and Cancer by Modulating miR-34a and miR-21 Expression

    Directory of Open Access Journals (Sweden)

    Julie Chao

    2017-01-01

    Full Text Available Kallistatin is an endogenous protein that regulates differential signaling pathways and a wide spectrum of biological activities via its two structural elements: an active site and a heparin-binding domain. Kallistatin via its heparin-binding site inhibits vascular inflammation and oxidative stress by antagonizing TNF-α-induced NADPH oxidase activity, NF-κB activation, and inflammatory gene expression in endothelial cells. Moreover, kallistatin via its active site inhibits microRNA-34a (miR-34a synthesis and stimulates eNOS and SIRT1 expression in endothelial progenitor cells, whereas its heparin-binding site is crucial for blocking TNF-α-induced miR-21 expression and oxidative stress, thus reducing cellular senescence. By downregulating miR-34a and miR-21 expression, kallistatin treatment attenuates oxidative damage and aortic senescence in streptozotocin-induced diabetic mice and extends Caenorhabditis elegans lifespan under stress conditions. Likewise, kallistatin through the heparin-binding site inhibits TGF-β-induced miR-21 synthesis and oxidative stress in endothelial cells, resulting in inhibition of endothelial-mesenchymal transition, a process contributing to fibrosis and cancer. Furthermore, kallistatin’s active site is essential for stimulating miR-34a and p53 expression and inhibiting the miR-21-Akt-Bcl-2 signaling pathway, thus inducing apoptosis in breast cancer cells. These findings reveal novel mechanisms of kallistatin in protection against senescence, aging, and cancer development by modulating miR-34a and miR-21 levels and inhibiting oxidative stress.

  3. Survivability-enhancing routing scheme for multi-domain networks

    DEFF Research Database (Denmark)

    Li, Xiaohua; Ruepp, Sarah Renée; Manolova, Anna Vasileva

    2008-01-01

    We present a routing solution which eliminates the inherent path exploration problem of BGP and thereby enhances survivability in multi-domain networks. The path exploration problem is caused by the dependency among paths learned from neighboring domains. We propose to solve this issue by using two...... the size of routing table is 2*(n-1). To implement our solution, domain level source routing is used and a SDRP header is added to the delivered packet. This avoids re-calculation and path exploration when repairing inter-domain link failures. Inter-domain link failures must be repaired at domain level...

  4. Two approaches to synthesis based on the domain theory

    DEFF Research Database (Denmark)

    Hansen, Claus Thorp; Andreasen, Mogens Myrup

    2002-01-01

    The domain theory is described in this chapter. By a strict distinction between the structural characteristics and the behavioural properties of a mechanical artefact, each domain, i.e. transformation-, organ-, and part domain, becomes a productive view for design of mechanical artefacts....... The functional reasoning within each domain and between the domains seems to be ruled by the function-means law (Hubka´s law). On the basis of the domain theory and the function-means law we present two formal approaches to the synthesis of mechanical artefacts, namely a design-process-oriented approach...

  5. Domain Walls and Matter-Antimatter Domains in the Early Universe

    Directory of Open Access Journals (Sweden)

    Dolgov A.D.

    2017-01-01

    Full Text Available We suggest a scenario of spontaneous (or dynamical C and CP violation according to which it is possible to generate domains of matter and antimatter separated by cosmologically large distances. Such C(CP violation existed only in the early universe and later it disappeared with the only trace of generated matter and antimatter domains. So this scenario does not suffer from the problem of domain walls. According to this scenario the width of the domain wall should grow exponentially to prevent annihilation at the domain boundaries. Though there is a classical result obtained by Basu and Vilenkin that the width of the wall tends to the one of the stationary solution (constant physical width. That is why we considered thick domain walls in a de Sitter universe following paper by Basu and Vilenkin. However, we were interested not only in stationary solutions found therein, but also investigated the general case of domain wall evolution with time. When the wall thickness parameter, δ0 , is smaller than H−1/2 where H is the Hubble parameter in de Sitter space-time, then the stationary solutions exist, and initial field configurations tend with time to the stationary ones. However, there are no stationary solutions for δ0>H−1/2 We have calculated numerically the rate of the wall expansion in this case and have found that the width of the wall grows exponentially fast for δ0≫H−1 An explanation for the critical value δ0c=H−1/2 is also proposed.

  6. IDDI: integrated domain-domain interaction and protein interaction analysis system.

    Science.gov (United States)

    Kim, Yul; Min, Bumki; Yi, Gwan-Su

    2012-06-21

    Deciphering protein-protein interaction (PPI) in domain level enriches valuable information about binding mechanism and functional role of interacting proteins. The 3D structures of complex proteins are reliable source of domain-domain interaction (DDI) but the number of proven structures is very limited. Several resources for the computationally predicted DDI have been generated but they are scattered in various places and their prediction show erratic performances. A well-organized PPI and DDI analysis system integrating these data with fair scoring system is necessary. We integrated three structure-based DDI datasets and twenty computationally predicted DDI datasets and constructed an interaction analysis system, named IDDI, which enables to browse protein and domain interactions with their relationships. To integrate heterogeneous DDI information, a novel scoring scheme is introduced to determine the reliability of DDI by considering the prediction scores of each DDI and the confidence levels of each prediction method in the datasets, and independencies between predicted datasets. In addition, we connected this DDI information to the comprehensive PPI information and developed a unified interface for the interaction analysis exploring interaction networks at both protein and domain level. IDDI provides 204,705 DDIs among total 7,351 Pfam domains in the current version. The result presents that total number of DDIs is increased eight times more than that of previous studies. Due to the increment of data, 50.4% of PPIs could be correlated with DDIs which is more than twice of previous resources. Newly designed scoring scheme outperformed the previous system in its accuracy too. User interface of IDDI system provides interactive investigation of proteins and domains in interactions with interconnected way. A specific example is presented to show the efficiency of the systems to acquire the comprehensive information of target protein with PPI and DDI relationships

  7. Cache Domains That are Homologous to, but Different from PAS Domains Comprise the Largest Superfamily of Extracellular Sensors in Prokaryotes.

    Science.gov (United States)

    Upadhyay, Amit A; Fleetwood, Aaron D; Adebali, Ogun; Finn, Robert D; Zhulin, Igor B

    2016-04-01

    Cellular receptors usually contain a designated sensory domain that recognizes the signal. Per/Arnt/Sim (PAS) domains are ubiquitous sensors in thousands of species ranging from bacteria to humans. Although PAS domains were described as intracellular sensors, recent structural studies revealed PAS-like domains in extracytoplasmic regions in several transmembrane receptors. However, these structurally defined extracellular PAS-like domains do not match sequence-derived PAS domain models, and thus their distribution across the genomic landscape remains largely unknown. Here we show that structurally defined extracellular PAS-like domains belong to the Cache superfamily, which is homologous to, but distinct from the PAS superfamily. Our newly built computational models enabled identification of Cache domains in tens of thousands of signal transduction proteins including those from important pathogens and model organisms. Furthermore, we show that Cache domains comprise the dominant mode of extracellular sensing in prokaryotes.

  8. Domain-General Factors Influencing Numerical and Arithmetic Processing

    Directory of Open Access Journals (Sweden)

    André Knops

    2017-12-01

    Full Text Available This special issue contains 18 articles that address the question how numerical processes interact with domain-general factors. We start the editorial with a discussion of how to define domain-general versus domain-specific factors and then discuss the contributions to this special issue grouped into two core numerical domains that are subject to domain-general influences (see Figure 1. The first group of contributions addresses the question how numbers interact with spatial factors. The second group of contributions is concerned with factors that determine and predict arithmetic understanding, performance and development. This special issue shows that domain-general (Table 1a as well as domain-specific (Table 1b abilities influence numerical and arithmetic performance virtually at all levels and make it clear that for the field of numerical cognition a sole focus on one or several domain-specific factors like the approximate number system or spatial-numerical associations is not sufficient. Vice versa, in most studies that included domain-general and domain-specific variables, domain-specific numerical variables predicted arithmetic performance above and beyond domain-general variables. Therefore, a sole focus on domain-general aspects such as, for example, working memory, to explain, predict and foster arithmetic learning is also not sufficient. Based on the articles in this special issue we conclude that both domain-general and domain-specific factors contribute to numerical cognition. But the how, why and when of their contribution still needs to be better understood. We hope that this special issue may be helpful to readers in constraining future theory and model building about the interplay of domain-specific and domain-general factors.

  9. Evolutionary history of the TBP-domain superfamily.

    Science.gov (United States)

    Brindefalk, Björn; Dessailly, Benoit H; Yeats, Corin; Orengo, Christine; Werner, Finn; Poole, Anthony M

    2013-03-01

    The TATA binding protein (TBP) is an essential transcription initiation factor in Archaea and Eucarya. Bacteria lack TBP, and instead use sigma factors for transcription initiation. TBP has a symmetric structure comprising two repeated TBP domains. Using sequence, structural and phylogenetic analyses, we examine the distribution and evolutionary history of the TBP domain, a member of the helix-grip fold family. Our analyses reveal a broader distribution than for TBP, with TBP-domains being present across all three domains of life. In contrast to TBP, all other characterized examples of the TBP domain are present as single copies, primarily within multidomain proteins. The presence of the TBP domain in the ubiquitous DNA glycosylases suggests that this fold traces back to the ancestor of all three domains of life. The TBP domain is also found in RNase HIII, and phylogenetic analyses show that RNase HIII has evolved from bacterial RNase HII via TBP-domain fusion. Finally, our comparative genomic screens confirm and extend earlier reports of proteins consisting of a single TBP domain among some Archaea. These monopartite TBP-domain proteins suggest that this domain is functional in its own right, and that the TBP domain could have first evolved as an independent protein, which was later recruited in different contexts.

  10. Shape and assembly of type IV procollagen obtained from cell culture.

    OpenAIRE

    Oberbäumer, I; Wiedemann, H.; Timpl, R; Kühn, K

    1982-01-01

    Type IV procollagen was isolated from the culture medium of the teratocarcinoma cell line PYS-2 by affinity chromatography on heparin-Sepharose. Immunological studies showed that type IV procollagen is composed of pro-alpha 1(IV) and pro-alpha 2(IV) chains and contains two potential cross-linking sites which are located in the short triple-helical 7S domain and the globular domain NC1 . The 7S domain was also identified as the heparin binding site. Rotary shadowing visualized type IV procolla...

  11. From striped domain to single domain: Evolution of partial dislocations in epitaxial silicene

    Science.gov (United States)

    Fleurence, Antoine; Yamada-Takamura, Yukiko

    Silicene is a graphene-analogue 2D material made of Si atoms. The mixed sp2/sp3 hybridization of the Si atom orbitals makes its atomistic structure particularly flexible. The epitaxial form of silicene that crystallizes spontaneously on the (0001) surface of zirconium diboride (ZrB2) thin films grown on Si(111) features a periodic one-dimensional domain structure resulting from the release of the stress. The domain boundaries are partial dislocations of the silicene lattice. The domain structure can be turned into a single domain by depositing an amount of silicon compensating the difference of Si atom density between the boundaries and the domains. This transformation requires the coherent motion of a large number of Si atoms to suppress the dislocations and to allow for the incorporation of Si atoms, which needs to overcome the repulsion between the boundaries. The flexibility of the silicene structure permits the monitoring of the partial dislocations disappearing upon Si deposition by room-temperature scanning tunneling microscopy. These observations give insights into how the dislocations are introduced and removed in 2D materials.

  12. Compassion and professional care: exploring the domain.

    Science.gov (United States)

    van der Cingel, Margreet

    2009-04-01

    Compassion unites people during times of suffering and distress. Unfortunately, compassion cannot take away suffering. Why then, is compassion important for people who suffer? Nurses work in a domain where human suffering is evidently present. In order to give meaning to compassion in the domain of professional care, it is necessary to describe what compassion is. The purpose of this paper is to explore questions and contradictions in the debate on compassion related to nursing care. The paper reviews classical philosophers as well as contemporary scientists' main arguments on compassion. First, I will examine the relationship between compassion and suffering. Second, how does one recognize serious suffering? This issue raises questions about the role of imagination and the need for identification. Third, literature describes compassion as an emotion. Some philosophers consider emotions uncontrollable feelings; others see a clear rational dimension in emotions. In order to determine what compassion is, it is necessary to weigh these contradictional arguments. Fourth, I will discuss motives for compassion. Is compassion an act of altruism or egoism? In this debate Nietzsche and Schopenhauer are well-known opponents. Today, analysis of their arguments leads to some surprising conclusions. Fifth, there is the issue of fault and compassion. Can we only feel compassionate when people who suffer are not to blame for their own suffering? Such a condition faces professional caretakers with a dilemma which needs a thorough analysis if compassion is to be of use in the field of professional care. Finally, I will explore the moral meaning of compassion. Compassion, described as a concept with cognitive as well as affective dimensions, also has volitional and behavioural aspects. These aspects specifically are of importance to nursing care and further research of compassion in the nursing domain.

  13. Domain Wall Evolution in Phase Transforming Oxides

    Science.gov (United States)

    2015-01-14

    Domain wall motion and electric?field?induced strains in NBT ?xBT solid solutions from in situ neutron diffraction,” T.-M. Usher,* J. S. Forrester, E...Morphotropic Phase Boundary of NBT ?BT,” L. M. Denis,* J. Glaum, M. Hoffman, J. Forrester, and J. L. Jones, Electronic Materials and Applications 2013...titanate (PZT) and lead-free compositions Na0.5K0.5NbO3 (NKN) and Na0.5Bi0.5TiO3 ( NBT ). This past year, we reported results on piezoelectric compositions

  14. Neutron scattering from polarised proton domains

    CERN Document Server

    Van den Brandt, B; Kohbrecher, J; Konter, J A; Mango, S; Glattli, H; Leymarie, E; Grillo, I; May, R P; Jouve, H; Stuhrmann, H B; Stuhrmann, H B; Zimmer, O

    2002-01-01

    Time-dependent small-angle polarised neutron scattering from domains of polarised protons has been observed at the onset of dynamic nuclear polarisation in a frozen solution of 98% deuterated glycerol-water at 1 K containing a small concentration of paramagnetic centres (EHBA-Cr sup V). Simultaneous NMR measurements show that the observed scattering arises from protons around the Cr sup V -ions which are polarised to approx 10% in a few seconds, much faster than the protons in the bulk. (authors)

  15. Multipath inter-domain policy routing

    OpenAIRE

    Amaral, Pedro Miguel Figueiredo

    2012-01-01

    Dissertação submetida para a obtenção do grau de Doutor em Engenharia Electrotécnica e de Computadores Routing can be abstracted to be a path nding problem in a graph that models the network. The problem can be modelled using an algebraic approach that describes the way routes are calculated and ranked. The shortest path problem is the most common form and consists in nding the path with the smallest cost. The inter-domain scenario introduces some new challenges to the routin...

  16. Designing Assistive Technologies for the ADHD Domain

    DEFF Research Database (Denmark)

    Sonne, Tobias; Grønbæk, Kaj

    (ADHD). In this paper, we identify a set of challenges that children with ADHD typically experience, which provides an empirical foundation for pervasive health researchers to address the ADHD domain. The work is grounded in extensive empirical studies and it is contextualized using literature on ADHD....... Based on these studies, we also present lessons learned that are relevant to consider when designing assistive technology to support children with ADHD. Finally, we provide an example (CASTT) of our own work to illustrate how the presented findings can frame research activities and be used to develop...... novel assistive technology to empower children with ADHD and improve their wellbeing....

  17. Decomposition and removability properties of John domains

    Indian Academy of Sciences (India)

    A quasidisk is the image of a disk or a half-plane under a quasiconformal mapping of the ... also a John domain, where P = {p1,p2,...,pm} and pi ∈ D (i = 1, 2,...,m). .... (2.5). Proof. Let S = ∂Bn(w1,r1)∩∂Bn(w2,r2). If S contains at most one point, then the proof is obvious. On the other hand, if S contains at least two points, ...

  18. Fermionic Zero Modes on Domain Walls

    OpenAIRE

    Stojkovic, Dejan

    2000-01-01

    We study fermionic zero modes in the domain wall background. The fermions have Dirac and left- and right-handed Majorana mass terms. The source of the Dirac mass term is the coupling to a scalar field $\\Phi$. The source of the Majorana mass terms could also be the coupling to a scalar field $\\Phi$ or a vacuum expectation value of some other field acquired in a phase transition well above the phase transition of the field $\\Phi$. We derive the fermionic equations of motion and find the necessa...

  19. Maximum Probability Domains for Hubbard Models

    CERN Document Server

    Acke, Guillaume; Claeys, Pieter W; Van Raemdonck, Mario; Poelmans, Ward; Van Neck, Dimitri; Bultinck, Patrick

    2015-01-01

    The theory of Maximum Probability Domains (MPDs) is formulated for the Hubbard model in terms of projection operators and generating functions for both exact eigenstates as well as Slater determinants. A fast MPD analysis procedure is proposed, which is subsequently used to analyse numerical results for the Hubbard model. It is shown that the essential physics behind the considered Hubbard models can be exposed using MPDs. Furthermore, the MPDs appear to be in line with what is expected from Valence Bond Theory-based knowledge.

  20. Developmental Disorders as Pathological Resilience Domains

    Directory of Open Access Journals (Sweden)

    Rodrick Wallace

    2008-06-01

    Full Text Available Ecosystem resilience theory permits novel exploration of developmental psychiatric and chronic physical disorders. Structured psychosocial stress, and similar noxious exposures, can write distorted images of themselves onto child growth, and, if sufficiently powerful, adult development as well, initiating a punctuated life course trajectory to characteristic forms of comorbid mind/body dysfunction. For an individual, within the linked network of broadly cognitive psysiological and mental subsystems, this occurs in a manner almost exactly similar to resilience domain shifts affecting a stressed ecosystem, suggesting that reversal or palliation may often be exceedingly difficult. Thus resilience theory may contribute significant new perspectives to the understanding, remediation, and prevention, of these debilitating conditions.

  1. Matters of fiber size and myonuclear domain

    DEFF Research Database (Denmark)

    Karlsen, Anders; Couppé, Christian; Andersen, Jesper L.

    2015-01-01

    INTRODUCTION: The relationship between fiber size and myonuclear content is understood poorly. METHODS: Biopsy cross-sections from young and old trained and untrained healthy individuals were analyzed for fiber area and myonuclei, and 2 fiber size-dependent cluster analyses were performed. RESULTS...... in fibers type II fibers below 3,000 μm(2) was observed in the old. DISCUSSION: These findings suggest that age-related reductions in myonuclear domain size could be explained by a larger proportion of small fibers and highlight the usefulness of fiber size...

  2. Landauer's principle in the quantum domain

    Directory of Open Access Journals (Sweden)

    Eric Lutz

    2010-06-01

    Full Text Available Recent papers discussing thermodynamic processes in strongly coupled quantum systems claim a violation of Landauer's principle and imply a violation of the second law of thermodynamics. If true, this would have powerful consequences. Perpetuum mobiles could be build as long as the operating temperature is brought close to zero. It would also have serious consequences on thermodynamic derivations of information theoretic results, such as the Holevo bound. Here we argue why these claims are erroneous. Correlations occurring in the strongly coupled, quantum domain require a rethink of how entropy, heat and work are calculated. It is shown that a consistent treatment solves the paradox.

  3. Ontological Engineering for the Cadastral Domain

    DEFF Research Database (Denmark)

    Stubkjær, Erik; Stuckenschmidt, Heiner

    2000-01-01

    The term 'ontology' has been used in many ways and across different communities. In th following we will introduce ontologies as an explication of some shared vocabulary or conceptualization of a specific subject matter. The main problem with the use of a shared vocabulary according to a specific...... conceptualization of the world is that much information remains implicit. Ontologies have set out to overcome the problem of implicit and hidden knowledge by making the conceptualization of a domain (e.g. mathematics) explicit. Ontological engineering is thus an approach to achieve a conceptual rigor...

  4. Dental optical coherence domain reflectometry explorer

    Energy Technology Data Exchange (ETDEWEB)

    Everett, Matthew J. (Livermore, CA); Colston, Jr., Billy W. (Livermore, CA); Sathyam, Ujwal S. (Livermore, CA); Da Silva, Luiz B. (Pleasanton, CA)

    2001-01-01

    A hand-held, fiber optic based dental device with optical coherence domain reflectometry (OCDR) sensing capabilities provides a profile of optical scattering as a function of depth in the tissue at the point where the tip of the dental explorer touches the tissue. This system provides information on the internal structure of the dental tissue, which is then used to detect caries and periodontal disease. A series of profiles of optical scattering or tissue microstructure are generated by moving the explorer across the tooth or other tissue. The profiles are combined to form a cross-sectional, or optical coherence tomography (OCT), image.

  5. Fourier transforms in the complex domain

    CERN Document Server

    Wiener, N

    1934-01-01

    With the aid of Fourier-Mellin transforms as a tool in analysis, the authors were able to attack such diverse analytic questions as those of quasi-analytic functions, Mercer's theorem on summability, Milne's integral equation of radiative equilibrium, the theorems of Münz and Szász concerning the closure of sets of powers of an argument, Titchmarsh's theory of entire functions of semi-exponential type with real negative zeros, trigonometric interpolation and developments in polynomials of the form \\sum^N_1A_ne^{i\\lambda_nx}, lacunary series, generalized harmonic analysis in the complex domain,

  6. Correlation between spin structure oscillations and domain wall velocities

    Science.gov (United States)

    Bisig, André; Stärk, Martin; Mawass, Mohamad-Assaad; Moutafis, Christoforos; Rhensius, Jan; Heidler, Jakoba; Büttner, Felix; Noske, Matthias; Weigand, Markus; Eisebitt, Stefan; Tyliszczak, Tolek; van Waeyenberge, Bartel; Stoll, Hermann; Schütz, Gisela; Kläui, Mathias

    2013-08-01

    Magnetic sensing and logic devices based on the motion of magnetic domain walls rely on the precise and deterministic control of the position and the velocity of individual magnetic domain walls in curved nanowires. Varying domain wall velocities have been predicted to result from intrinsic effects such as oscillating domain wall spin structure transformations and extrinsic pinning due to imperfections. Here we use direct dynamic imaging of the nanoscale spin structure that allows us for the first time to directly check these predictions. We find a new regime of oscillating domain wall motion even below the Walker breakdown correlated with periodic spin structure changes. We show that the extrinsic pinning from imperfections in the nanowire only affects slow domain walls and we identify the magnetostatic energy, which scales with the domain wall velocity, as the energy reservoir for the domain wall to overcome the local pinning potential landscape.

  7. Epidermal growth factor (EGF) ligand release by substrate-specific a disintegrin and metalloproteases (ADAMs) involves different protein kinase C (PKC) isoenzymes depending on the stimulus.

    Science.gov (United States)

    Dang, Michelle; Dubbin, Karen; D'Aiello, Antonio; Hartmann, Monika; Lodish, Harvey; Herrlich, Andreas

    2011-05-20

    The dysregulation of EGF family ligand cleavage has severe consequences for the developing as well as the adult organism. Therefore, their production is highly regulated. The limiting step is the ectodomain cleavage of membrane-bound precursors by one of several a disintegrin and metalloprotease (ADAM) metalloproteases, and understanding the regulation of cleavage is an important goal of current research. We have previously reported that in mouse lung epithelial cells, the pro-EGF ligands TGFα, neuregulin 1β (NRG), and heparin-binding EGF are differentially cleaved depending on the cleavage stimulus (Herrlich, A., Klinman, E., Fu, J., Sadegh, C., and Lodish, H. (2008) FASEB J.). In this study in mouse embryonic fibroblasts that lack different ADAMs, we show that induced cleavage of EGF ligands can involve the same substrate-specific metalloprotease but does require different stimulus-dependent signaling pathways. Cleavage was stimulated by phorbol ester (12-O-tetradecanoylphorbol-13-acetate (TPA), a mimic of diacylglycerol and PKC activator), hypertonic stress, lysophosphatidic acid (LPA)-induced G protein-coupled receptor activation, or by ionomycin-induced intracellular calcium release. Although ADAMs showed substrate preference (ADAM17, TGFα and heparin-binding EGF; and ADAM9, NRG), substrate cleavage differed substantially with the stimulus, and cleavage of the same substrate depended on the presence of different, sometimes multiple, PKC isoforms. For instance, classical PKC was required for TPA-induced but not hypertonic stress-induced cleavage of all EGF family ligands. Inhibition of PKCζ enhanced NRG release upon TPA stimulation, but it blocked NRG release in response to hypertonic stress. Our results suggest a model in which substantial regulation of ectodomain cleavage occurs not only on the metalloprotease level but also on the level of the substrate or of a third protein. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Extending the Effective Ranging Depth of Spectral Domain Optical Coherence Tomography by Spatial Frequency Domain Multiplexing

    Directory of Open Access Journals (Sweden)

    Tong Wu

    2016-11-01

    Full Text Available We present a spatial frequency domain multiplexing method for extending the imaging depth range of a spectral domain optical coherence tomography (SDOCT system without any expensive device. This method uses two galvo scanners with different pivot-offset distances in two independent reference arms for spatial frequency modulation and multiplexing. The spatial frequency contents corresponding to different depth regions of the sample can be shifted to different frequency bands. The spatial frequency domain multiplexing SDOCT system provides an approximately 1.9-fold increase in the effective ranging depth compared with that of a conventional full-range SDOCT system. The reconstructed images of phantom and biological tissue demonstrate the expected increase in ranging depth. The parameters choice criterion for this method is discussed.

  9. Domain Endurants: An Analysis and Description Process Model

    DEFF Research Database (Denmark)

    Bjørner, Dines

    2014-01-01

    We present a summary, Sect. 2, of a structure of domain analysis and description concepts: techniques and tools. And we link, in Sect. 3, these concepts, embodied in domain analysis prompts and domain description prompts, in a model of how a diligent domain analyser cum describer would use them. We...... claim that both sections, Sects. 2–3, contribute to a methodology of software engineering....

  10. When and how to develop domain-specific languages

    OpenAIRE

    Mernik, Marjan; Heering, Jan; Sloane, A.M.

    2003-01-01

    textabstractDomain-specific languages (DSLs) are languages tailored to a specific application domain. They offer substantial gains in expressiveness and ease of use compared with general purpose programming languages in their domain of application. DSL development is hard, requiring both domain knowledge and language development expertise. Few people have both. Not surprisingly, the decision to develop a DSL is often postponed indefinitely, if considered at all, and most DSLs never get beyond...

  11. Analysis of tiltrotor whirl flutter in time and frequency domain

    DEFF Research Database (Denmark)

    Kim, Taeseong; Shin, SanJoon; Kim, Taehyoun

    2009-01-01

    flexible wing modes. Numerical results are obtained in both time and frequency domains. Generalized eigenvalue solution is utilized to estimate the whirl flutter stability in the frequency domain, and Runge-Kutta method is used to analyze it in time domain. The effects of varying the pylon spring stiffness...

  12. A Hierarchy of Management Training Requirements: The Competency Domain Model.

    Science.gov (United States)

    Sandwith, Paul

    1993-01-01

    The Competency Domain Model has five domains of management competencies: conceptual/creative, leadership, interpersonal, administrative, and technical. Specific competencies and training plans can be identified in each domain for different levels--first line supervisor, field office manager, assistant manager, area manager, director of operations.…

  13. Evaluation of Damping Using Frequency Domain Operational Modal Analysis Techniques

    DEFF Research Database (Denmark)

    Bajric, Anela; Georgakis, Christos T.; Brincker, Rune

    2015-01-01

    domain techniques, the Frequency Domain Decomposition (FDD) and the Frequency Domain Polyreference (FDPR). The response of a two degree-of-freedom (2DOF) system is numerically established with specified modal parameters subjected to white noise loading. The system identification is evaluated with well...

  14. Phase transition in a domain-wall lattice

    Science.gov (United States)

    Stolzenberg, M.; Lyuksyutov, I.; Bauer, E.

    1991-12-01

    A new type of phase transition in the domain-wall lattice between the (4×2) and (5×2) structure of Te on Mo(110) is reported. In this phase transition the period of the uniaxial domain-wall lattice remains constant, but domain walls themselves transform in more heavy ones.

  15. Domain Specificity between Peer Support and Self-Concept

    Science.gov (United States)

    Leung, Kim Chau; Marsh, Herbert W.; Craven, Rhonda G.; Yeung, Alexander S.; Abduljabbar, Adel S.

    2013-01-01

    Peer support interventions have mostly neglected the domain specificity of intervention effects. In two studies, the present investigation examined the domain specificity of peer support interventions targeting specific domains of self-concept. In Study 1, participants ("n" = 50) who had received an academically oriented peer support…

  16. Sobolev Embedding Theorems for a Class of Anisotropic Irregular Domains

    NARCIS (Netherlands)

    Trushin, B. V.

    Sufficient conditions for the embedding of a Sobolev space in Lebesgue spaces on a domain depend on the integrability and smoothness parameters of the spaces and on the geometric features of the domain. In the present paper, Sobolev embedding theorems are obtained for a class of domains with

  17. Entropy based classifier for cross-domain opinion mining

    Directory of Open Access Journals (Sweden)

    Jyoti S. Deshmukh

    2018-01-01

    Full Text Available In recent years, the growth of social network has increased the interest of people in analyzing reviews and opinions for products before they buy them. Consequently, this has given rise to the domain adaptation as a prominent area of research in sentiment analysis. A classifier trained from one domain often gives poor results on data from another domain. Expression of sentiment is different in every domain. The labeling cost of each domain separately is very high as well as time consuming. Therefore, this study has proposed an approach that extracts and classifies opinion words from one domain called source domain and predicts opinion words of another domain called target domain using a semi-supervised approach, which combines modified maximum entropy and bipartite graph clustering. A comparison of opinion classification on reviews on four different product domains is presented. The results demonstrate that the proposed method performs relatively well in comparison to the other methods. Comparison of SentiWordNet of domain-specific and domain-independent words reveals that on an average 72.6% and 88.4% words, respectively, are correctly classified.

  18. Conserved C-terminal nascent peptide binding domain of HYPK ...

    Indian Academy of Sciences (India)

    2014-07-09

    Jul 9, 2014 ... viability and decreases caspase activities in Huntington's disease (HD) cell culture model. This domain is found to be required ... Huntington's disease (HD), this domain reduces cellular toxicity. We also find that ..... the adaptive functional value conferred by the NPAA domain of. HYPK is quite higher in case ...

  19. Cross-domain active learning for video concept detection

    Science.gov (United States)

    Li, Huan; Li, Chao; Shi, Yuan; Xiong, Zhang; Hauptmann, Alexander G.

    2011-08-01

    As video data from a variety of different domains (e.g., news, documentaries, entertainment) have distinctive data distributions, cross-domain video concept detection becomes an important task, in which one can reuse the labeled data of one domain to benefit the learning task in another domain with insufficient labeled data. In this paper, we approach this problem by proposing a cross-domain active learning method which iteratively queries labels of the most informative samples in the target domain. Traditional active learning assumes that the training (source domain) and test data (target domain) are from the same distribution. However, it may fail when the two domains have different distributions because querying informative samples according to a base learner that initially learned from source domain may no longer be helpful for the target domain. In our paper, we use the Gaussian random field model as the base learner which has the advantage of exploring the distributions in both domains, and adopt uncertainty sampling as the query strategy. Additionally, we present an instance weighting trick to accelerate the adaptability of the base learner, and develop an efficient model updating method which can significantly speed up the active learning process. Experimental results on TRECVID collections highlight the effectiveness.

  20. The role of domain analysis in prediction instrument development

    NARCIS (Netherlands)

    van der Spoel, Sjoerd; Amrit, Chintan Amrit; van Hillegersberg, Jos

    2016-01-01

    In order to develop prediction instruments that have sufficient predictive power, it is essential to understand the specific domain the prediction instrument is developed for. This domain analysis is especially important for domains where human behavior, politics, or other soft factors play a role.