WorldWideScience

Sample records for featuring diquinone moieties

  1. Oxidation of the Primary Alcoholic Moiety Selectively in the Presence of the Secondary Alcoholic Moieties

    International Nuclear Information System (INIS)

    Tin Myint Htwe

    2011-12-01

    Both primary and secondary alcoholic moieties are very sensitive to oxidation reactions. But sometimes it is necessary to oxidized only the primary alcoholic moiety. Such cases are usually found in Food Industries. In this situation, TEMPO (1, 1, 6, 6-Tetramethyl-1-Piperidine Oxoammonium) was used as an oxidizing agent. In this paper, Alpha starch was successfully oxidized using TEMPO as the oxidizing agent in combination with sodium hypochlorite with and without sodium bromide. The oxidation of primary alcoholic moiety only and the remaining untouched secondary alcoholic moiety were proved by infrared spectroscopy method.

  2. Examination of adipose depot-specific PPAR moieties

    Energy Technology Data Exchange (ETDEWEB)

    Dodson, M.V., E-mail: dodson@wsu.edu [Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States); Vierck, J.L. [Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States); Hausman, G.J. [USDA-ARS, Richard B. Russell Agricultural Research Station, Athens, GA 30604 (United States); Guan, L.L. [Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5 Canada (Canada); Fernyhough, M.E. [The Hartz Mountain Corporation, Secaucus, NJ 07094 (United States); Poulos, S.P. [The Coca-Cola Company, Research and Technology, Atlanta, GA 30313 (United States); Mir, P.S. [Agriculture and Agri-Food Canada Research Centre, Lethbridge, CA T1J 4B1 (United States); Jiang, Z. [Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States)

    2010-04-02

    Molecular mechanisms of peroxisome proliferator activated receptors (PPARs) are being defined rapidly, as illustrated by the volume of papers published. Much of the research is directed towards a clinical end-point/application; however, the non-homogeneous nature of adipose depots in laboratory animals is spurring similar research in domestic meat animals (such as beef cattle). Moreover, the size of adipose depots in meat animals remains an attractive feature for using them to obtain cells for PPAR research. Examination of meat-animal depot-specific PPAR moieties may provide novel information about adipocyte regulation that might be extrapolated to all animals.

  3. Examination of adipose depot-specific PPAR moieties

    International Nuclear Information System (INIS)

    Dodson, M.V.; Vierck, J.L.; Hausman, G.J.; Guan, L.L.; Fernyhough, M.E.; Poulos, S.P.; Mir, P.S.; Jiang, Z.

    2010-01-01

    Molecular mechanisms of peroxisome proliferator activated receptors (PPARs) are being defined rapidly, as illustrated by the volume of papers published. Much of the research is directed towards a clinical end-point/application; however, the non-homogeneous nature of adipose depots in laboratory animals is spurring similar research in domestic meat animals (such as beef cattle). Moreover, the size of adipose depots in meat animals remains an attractive feature for using them to obtain cells for PPAR research. Examination of meat-animal depot-specific PPAR moieties may provide novel information about adipocyte regulation that might be extrapolated to all animals.

  4. Polyethene with pendant fullerene moieties

    NARCIS (Netherlands)

    Zhang, XC; Sieval, AB; Hummelen, JC; Hessen, B; Zhang, Xiaochun

    2005-01-01

    Polyethene with fullerene moieties pendant on short-chain branches was prepared by the catalytic copolymerisation of ethene and a fullerene-containing vinylic comonomer, yielding polyethene copolymers containing up to 25 wt% of C-60.

  5. Synthesis of the Sugar Moieties

    Science.gov (United States)

    Grynkiewicz, Grzegorz; Szeja, Wieslaw

    Biological activity of the anthracycline antibiotics, which have found wide application in clinical oncology, is strongly related to their glycosidic structure. Modification or switch of the saccharide moiety became an important line of new drug discovery and study of their mechanism of action. Natural glycons (sugar moieties) of the anthracycline antibiotics belong to the 2,6-dideoxypyranose family and their principal representative, daunosamine, is 3-amino-2,3,6-trideoxy- l-lyxo-pyranose. Some newer chemical syntheses of this sugar, from a chiral pool as well as from achiral starting materials, are presented and their capability for scale-up and process development are commented upon. Rational sugar structural modifications, which are either useful for synthetic purposes or offer advantages in experimental therapy of cancer, are discussed from the chemical point of view.

  6. An unprecedented two-fold nested super-polyrotaxane: sulfate-directed hierarchical polythreading assembly of uranyl polyrotaxane moieties

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Lei; Wu, Qun-yan; Yuan, Li-yong; Wang, Lin; An, Shu-wen; Xie, Zhen-ni; Hu, Kong-qiu; Shi, Wei-qun [Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing (China); Chai, Zhi-fang [Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing (China); School of Radiological and Interdisciplinary Sciences and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou (China); Burns, Peter C. [Department of Chemistry and Biochemistry, University of Notre Dame, IN (United States)

    2016-08-01

    The hierarchical assembly of well-organized submoieties could lead to more complicated superstructures with intriguing properties. We describe herein an unprecedented polyrotaxane polythreading framework containing a two-fold nested super-polyrotaxane substructure, which was synthesized through a uranyl-directed hierarchical polythreading assembly of one-dimensional polyrotaxane chains and two-dimensional polyrotaxane networks. This special assembly mode actually affords a new way of supramolecular chemistry instead of covalently linked bulky stoppers to construct stable interlocked rotaxane moieties. An investigation of the synthesis condition shows that sulfate can assume a vital role in mediating the formation of different uranyl species, especially the unique trinuclear uranyl moiety [(UO{sub 2}){sub 3}O(OH){sub 2}]{sup 2+}, involving a notable bent [O=U=O] bond with a bond angle of 172.0(9) . Detailed analysis of the coordination features, the thermal stability as well as a fluorescence, and electrochemical characterization demonstrate that the uniqueness of this super-polyrotaxane structure is mainly closely related to the trinuclear uranyl moiety, which is confirmed by quantum chemical calculations. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Azomesogens with a heterocyclic moiety

    Indian Academy of Sciences (India)

    Unknown

    Azomesogens with a heterocyclic moiety. †. JAYRANG S DAVE and MEERA MENON*. Department of Applied Chemistry, Faculty of Technology and Engineering, MS University of Baroda,. Baroda 390 001, India. Abstract. Azobenzene derivatives were among the first ten liquid crystalline compounds. But there have been.

  8. One-Pot Synthesis of Cu(II Complex with Partially Oxidized TTF Moieties

    Directory of Open Access Journals (Sweden)

    Hiroki Oshio

    2012-07-01

    Full Text Available The one-pot synthesis of a Cu(II complex with partially oxidized tetrathiafulvalene (TTF moieties in its capping MT-Hsae-TTF ligands, [CuII(MT-sae-TTF2] [CuICl2] was realized by the simultaneous occurrence of Cu(II complexation and CuIICl2 mediated oxidation of TTF moieties. The crystal structure was composed of one-dimensional columns formed by partially oxidized TTF moieties and thus the cation radical salt showed relatively high electrical conductivity. Tight binding band structure calculations indicated the existence of a Peierls gap due to the tetramerization of the TTF moieties in the one-dimensional stacking column at room temperature, which is consistent with the semiconducting behavior of this salt.

  9. Rearrangement of beta,gamma-unsaturated esters with thallium trinitrate: synthesis of indans bearing a beta-keto ester moiety

    Directory of Open Access Journals (Sweden)

    Silva Jr. Luiz F.

    2006-01-01

    Full Text Available The rearrangement of beta,gamma-unsaturated esters, such as 2-(3,4-dihydronaphthalen-1-yl-propionic acid ethyl ester, with thallium trinitrate (TTN in acetic acid leads to 3-indan-1-yl-2-methyl-3-oxo-propionic acid ethyl ester in good yield, through a ring contraction reaction. The new indans thus obtained feature a beta-keto ester moiety, which would be useful for further functionalization.

  10. Identification of Conserved Moieties in Metabolic Networks by Graph Theoretical Analysis of Atom Transition Networks

    Science.gov (United States)

    Haraldsdóttir, Hulda S.; Fleming, Ronan M. T.

    2016-01-01

    Conserved moieties are groups of atoms that remain intact in all reactions of a metabolic network. Identification of conserved moieties gives insight into the structure and function of metabolic networks and facilitates metabolic modelling. All moiety conservation relations can be represented as nonnegative integer vectors in the left null space of the stoichiometric matrix corresponding to a biochemical network. Algorithms exist to compute such vectors based only on reaction stoichiometry but their computational complexity has limited their application to relatively small metabolic networks. Moreover, the vectors returned by existing algorithms do not, in general, represent conservation of a specific moiety with a defined atomic structure. Here, we show that identification of conserved moieties requires data on reaction atom mappings in addition to stoichiometry. We present a novel method to identify conserved moieties in metabolic networks by graph theoretical analysis of their underlying atom transition networks. Our method returns the exact group of atoms belonging to each conserved moiety as well as the corresponding vector in the left null space of the stoichiometric matrix. It can be implemented as a pipeline of polynomial time algorithms. Our implementation completes in under five minutes on a metabolic network with more than 4,000 mass balanced reactions. The scalability of the method enables extension of existing applications for moiety conservation relations to genome-scale metabolic networks. We also give examples of new applications made possible by elucidating the atomic structure of conserved moieties. PMID:27870845

  11. Mutagenicity of quaternary ammonium salts containing carbohydrate moieties

    Energy Technology Data Exchange (ETDEWEB)

    Dmochowska, Barbara [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Piosik, Jacek; Woziwodzka, Anna [Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kladki 24, 80-822 Gdansk (Poland); Sikora, Karol; Wisniewski, Andrzej [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Wegrzyn, Grzegorz, E-mail: wegrzyn@biotech.univ.gda.pl [Department of Molecular Biology, University of Gdansk, Kladki 24, 80-822 Gdansk (Poland)

    2011-10-15

    Highlights: {yields} A series of quaternary ammonium salts containing carbohydrate moieties, with configuration D-galacto, D-gluco and D-manno, was synthesized and characterized. {yields} The quaternary ammonium salts containing carbohydrate moieties revealed potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. {yields} The N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. {yields} We suggest that quaternary ammonium salts may be more hazardous than previously supposed. - Abstract: Quaternary ammonium salts are widely used in industrial, agricultural, healthcare and domestic applications. They are believed to be safe compounds, with little or no health hazard to humans. However, in this report, we demonstrate that a series of newly synthesized quaternary ammonium salts containing carbohydrate moieties reveal potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. D-Gluco- and D-galacto-derivatives were found to have a higher mutagenic potential than D-manno-derivatives. Among the former groups of compounds, the N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. These results suggest that the safety of quaternary ammonium salts may be lower than previously supposed, indicating a need for testing such compounds for their mutagenicity.

  12. Mutagenicity of quaternary ammonium salts containing carbohydrate moieties

    International Nuclear Information System (INIS)

    Dmochowska, Barbara; Piosik, Jacek; Woziwodzka, Anna; Sikora, Karol; Wisniewski, Andrzej; Wegrzyn, Grzegorz

    2011-01-01

    Highlights: → A series of quaternary ammonium salts containing carbohydrate moieties, with configuration D-galacto, D-gluco and D-manno, was synthesized and characterized. → The quaternary ammonium salts containing carbohydrate moieties revealed potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. → The N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. → We suggest that quaternary ammonium salts may be more hazardous than previously supposed. - Abstract: Quaternary ammonium salts are widely used in industrial, agricultural, healthcare and domestic applications. They are believed to be safe compounds, with little or no health hazard to humans. However, in this report, we demonstrate that a series of newly synthesized quaternary ammonium salts containing carbohydrate moieties reveal potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. D-Gluco- and D-galacto-derivatives were found to have a higher mutagenic potential than D-manno-derivatives. Among the former groups of compounds, the N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. These results suggest that the safety of quaternary ammonium salts may be lower than previously supposed, indicating a need for testing such compounds for their mutagenicity.

  13. A series of copper complexes with carbazole and oxadiazole moieties: Synthesis, characterization and luminescence performance

    Energy Technology Data Exchange (ETDEWEB)

    Bai Weiyang, E-mail: baiwy02@163.com [College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054 (China); Sun Li [Graduate University of Chinese Academy of Sciences, Beijing 100049 (China)

    2012-10-15

    In this paper, various moieties of ethyl, carbazole and oxadiazole are attached to 2-thiazol-4-yl-1H-benzoimidazole to form a series of diamine ligands. Their corresponding Cu(I) complexes are also synthesized using bis(2-(diphenylphosphanyl)phenyl) ether as the auxiliary ligand. Crystal structures, thermal property, electronic nature and luminescence property of these Cu(I) complexes are discussed in detail. These Cu(I) complexes are found to be efficient green-emitting ones in solutions and the emissive parameters are improved largely by the incorporation of substituent moieties. Detailed analysis suggests that the effective suppression of solvent-induced exciplex quenching is responsible for this phenomenon. On the other hand, the introduction of substituent moieties exerts no obvious influence on molecular structure, thermal stability and emitting-energy of the Cu(I) complexes, owing to their absence from inner coordination sphere. - Highlights: Black-Right-Pointing-Pointer Diamine ligands with various moieties and Cu(I) complexes are synthesized. Black-Right-Pointing-Pointer Crystal structures and photophysical property are discussed in detail. Black-Right-Pointing-Pointer The incorporation of substituent moieties improves luminescence performance. Black-Right-Pointing-Pointer Solvent-induced exciplex quenching is suppressed by substituent moieties.

  14. Macromolecular Networks Containing Fluorinated Cyclic Moieties

    Science.gov (United States)

    2015-12-12

    Briefing Charts 3. DATES COVERED (From - To) 17 Nov 2015 – 12 Dec 2015 4. TITLE AND SUBTITLE Macromolecular Networks Containing Fluorinated Cyclic... FLUORINATED CYCLIC MOIETIES 12 December 2015 Andrew J. Guenthner,1 Scott T. Iacono,2 Cynthia A. Corley,2 Christopher M. Sahagun,3 Kevin R. Lamison,4...Reinforcements Good Flame, Smoke, & Toxicity Characteristics Low Water Uptake with Near Zero Coefficient of Hygroscopic Expansion ∆ DISTRIBUTION A

  15. Method for determining the composition of the sugar moiety of a sugar containing compound

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to methods of labeling sugar moieties of sugar containing compounds including glycopeptides. The compounds presented in the present invention facilitate reliable detection of sugar moieties of sugar containing compounds by a combination of spectroscopy methods...

  16. The disaccharide moiety of bleomycin facilitates uptake by cancer cells.

    Science.gov (United States)

    Schroeder, Benjamin R; Ghare, M Imran; Bhattacharya, Chandrabali; Paul, Rakesh; Yu, Zhiqiang; Zaleski, Paul A; Bozeman, Trevor C; Rishel, Michael J; Hecht, Sidney M

    2014-10-01

    The disaccharide moiety is responsible for the tumor cell targeting properties of bleomycin (BLM). While the aglycon (deglycobleomycin) mediates DNA cleavage in much the same fashion as bleomycin, it exhibits diminished cytotoxicity in comparison to BLM. These findings suggested that BLM might be modular in nature, composed of tumor-seeking and tumoricidal domains. To explore this possibility, BLM analogues were prepared in which the disaccharide moiety was attached to deglycobleomycin at novel positions, namely, via the threonine moiety or C-terminal substituent. The analogues were compared with BLM and deglycoBLM for DNA cleavage, cancer cell uptake, and cytotoxic activity. BLM is more potent than deglycoBLM in supercoiled plasmid DNA relaxation, while the analogue having the disaccharide on threonine was less active than deglycoBLM and the analogue containing the C-terminal disaccharide was slightly more potent. While having unexceptional DNA cleavage potencies, both glycosylated analogues were more cytotoxic to cultured DU145 prostate cancer cells than deglycoBLM. Dye-labeled conjugates of the cytotoxic BLM aglycons were used in imaging experiments to determine the extent of cell uptake. The rank order of internalization efficiencies was the same as their order of cytotoxicities toward DU145 cells. These findings establish a role for the BLM disaccharide in tumor targeting/uptake and suggest that the disaccharide moiety may be capable of delivering other cytotoxins to cancer cells. While the mechanism responsible for uptake of the BLM disaccharide selectively by tumor cells has not yet been established, data are presented which suggest that the metabolic shift to glycolysis in cancer cells may provide the vehicle for selective internalization.

  17. CNDO/SCF molecular orbital structural studies and charge transfer ...

    African Journals Online (AJOL)

    dimethoxy- diquinone (DQ) has been discussed and compared with some related compounds. The electron transfer between DQ and uracil was studied in ethanol as an interaction medium. The ionization potentials and the electron affinities of the ...

  18. White emission from liquid-crystalline copolymers containing oxadiazole moieties in the side chain

    Science.gov (United States)

    Kawamoto, Masuki; Tsukamoto, Takuji; Kinoshita, Motoi; Ikeda, Tomiki

    2006-09-01

    A liquid-crystalline polymer in the side chain was synthesized through copolymerization of a bipolar carrier-transporting monomer with a liquid-crystalline monomer containing oxadiazole moieties substituted with trifluoromethyl groups. A single-layer light-emitting diode of indium tin oxide (ITO)/copolymer/MgAg emitted white light with a maximum luminous efficiency of 0.1cd/A. The origin of the white emission in the copolymer is the electroplex between bipolar carrier-transporting moieties and strong electron-withdrawing moieties. Furthermore, a simple multilayer device with configuration of ITO/poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonic acid)/copolymer/MgAg device showed white emission with CIE 1931 chromaticity coordinates (x,y): (0.30, 0.33).

  19. Identifying all moiety conservation laws in genome-scale metabolic networks.

    Science.gov (United States)

    De Martino, Andrea; De Martino, Daniele; Mulet, Roberto; Pagnani, Andrea

    2014-01-01

    The stoichiometry of a metabolic network gives rise to a set of conservation laws for the aggregate level of specific pools of metabolites, which, on one hand, pose dynamical constraints that cross-link the variations of metabolite concentrations and, on the other, provide key insight into a cell's metabolic production capabilities. When the conserved quantity identifies with a chemical moiety, extracting all such conservation laws from the stoichiometry amounts to finding all non-negative integer solutions of a linear system, a programming problem known to be NP-hard. We present an efficient strategy to compute the complete set of integer conservation laws of a genome-scale stoichiometric matrix, also providing a certificate for correctness and maximality of the solution. Our method is deployed for the analysis of moiety conservation relationships in two large-scale reconstructions of the metabolism of the bacterium E. coli, in six tissue-specific human metabolic networks, and, finally, in the human reactome as a whole, revealing that bacterial metabolism could be evolutionarily designed to cover broader production spectra than human metabolism. Convergence to the full set of moiety conservation laws in each case is achieved in extremely reduced computing times. In addition, we uncover a scaling relation that links the size of the independent pool basis to the number of metabolites, for which we present an analytical explanation.

  20. Identifying all moiety conservation laws in genome-scale metabolic networks.

    Directory of Open Access Journals (Sweden)

    Andrea De Martino

    Full Text Available The stoichiometry of a metabolic network gives rise to a set of conservation laws for the aggregate level of specific pools of metabolites, which, on one hand, pose dynamical constraints that cross-link the variations of metabolite concentrations and, on the other, provide key insight into a cell's metabolic production capabilities. When the conserved quantity identifies with a chemical moiety, extracting all such conservation laws from the stoichiometry amounts to finding all non-negative integer solutions of a linear system, a programming problem known to be NP-hard. We present an efficient strategy to compute the complete set of integer conservation laws of a genome-scale stoichiometric matrix, also providing a certificate for correctness and maximality of the solution. Our method is deployed for the analysis of moiety conservation relationships in two large-scale reconstructions of the metabolism of the bacterium E. coli, in six tissue-specific human metabolic networks, and, finally, in the human reactome as a whole, revealing that bacterial metabolism could be evolutionarily designed to cover broader production spectra than human metabolism. Convergence to the full set of moiety conservation laws in each case is achieved in extremely reduced computing times. In addition, we uncover a scaling relation that links the size of the independent pool basis to the number of metabolites, for which we present an analytical explanation.

  1. Fluoride-induced modulation of ionic transport in asymmetric nanopores functionalized with "caged" fluorescein moieties.

    Science.gov (United States)

    Ali, Mubarak; Ahmed, Ishtiaq; Ramirez, Patricio; Nasir, Saima; Cervera, Javier; Niemeyer, Christof M; Ensinger, Wolfgang

    2016-04-28

    We demonstrate experimentally and theoretically a nanofluidic fluoride sensing device based on a single conical pore functionalized with "caged" fluorescein moieties. The nanopore functionalization is based on an amine-terminated fluorescein whose phenolic hydroxyl groups are protected with tert-butyldiphenylsilyl (TBDPS) moieties. The protected fluorescein (Fcn-TBDPS-NH2) molecules are then immobilized on the nanopore surface via carbodiimide coupling chemistry. Exposure to fluoride ions removes the uncharged TBDPS moieties due to the fluoride-promoted cleavage of the silicon-oxygen bond, leading to the generation of negatively charged groups on the fluorescein moieties immobilized onto the pore surface. The asymmetrical distribution of these groups along the conical nanopore leads to the electrical rectification observed in the current-voltage (I-V) curve. On the contrary, other halides and anions are not able to induce any significant ionic rectification in the asymmetric pore. In each case, the success of the chemical functionalization and deprotection reactions is monitored through the changes observed in the I-V curves before and after the specified reaction step. The theoretical results based on the Nernst-Planck and Poisson equations further demonstrate the validity of an experimental approach to fluoride-induced modulation of nanopore current rectification behaviour.

  2. Side chain polysiloxanes with phthalocyanine moieties

    Directory of Open Access Journals (Sweden)

    T. Ganicz

    2012-05-01

    Full Text Available Side chain polysiloxane with 5-(pentyloxy-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxyphthalocyanine moieties is synthesized by hydrosilylation reaction. The phase behavior and thermooptical properties of the polysiloxane and starting 2-(pent-4-enyloxy-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxyphthalocyanine is examined by POM (Polarizing optical microscopy, TOA (thermooptical analysis, DSC (differential scanning calorimetry, AFM (atomic force microscopy and SAXS (small angle X-ray scattering studies. The effect of the attachment of phthalocyanine to polysiloxane chains over phase transitions and phase morphology is discussed in details.

  3. Subtilisin-catalyzed esterification of di- and oligosaccharides containing a d-fructose moiety

    International Nuclear Information System (INIS)

    Riva, S.; Nonini, M.; Ottolina, G.; Danieli, B.

    1998-01-01

    Several di- and oligosaccharides containing a d-fructose moiety have been acylated by protease subtilisin in anhydrous dimethylformamide in the presence of the activated ester trifluoroethyl butanoate. Under the reaction conditions used, all the substrates were converted into the corresponding monobutanoates in ca. 50% isolated yields. Structural determination of the products by 13 C NMR indicated a strong preference of subtilisin towards the regioselective esterification of the primary hydroxyls of the fructose moiety and, specifically, of the C-1 OH, as already observed with sucrose. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Lanthanide coordination polymers based on multi-donor ligand containing pyridine and phthalate moieties: Structures, luminescence and magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xun [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Liu, Lang [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450002 (China); College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Wang, Li-Ya, E-mail: wlya@lynu.edu.cn [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang 473601 (China); Song, Hong-Liang; Qiang Shi, Zhi; Wu, Xu-Hong [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022 (China); Ng, Seik-Weng [Department of Chemistry, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 80203 (Saudi Arabia)

    2013-10-15

    A new family of five lanthanide-organic coordination polymers incorporating multi-functional N-hetrocyclic dicarboxylate ligand, namely, [Ln{sub 2}(Hdpp){sub 2}(dpp){sub 2}]{sub n}Ln=Pr(1), Eu(2), Gd(3), Dy(4), Er(5) (H{sub 2}dpp=1-(3, 4-dicarboxyphenyl) pyridin-4-ol) have been fabricated successfully through solvothermal reaction of 1-(3,4-dicarboxyphenyl)-4-hydroxypyridin-1-ium chloride with trivalent lanthanide salts, and have been characterized systematically. The complexes 1–5 are isomorphous and isostructural. They all feature three dimensional (3D) frameworks based on the interconnection of 1D double chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 4+} basic carboxylate as secondary building unit (SBU). The results of magnetic analysis shows the same bridging fashion of carboxylic group in this case results in the different magnetic properties occurring within lanthanide polymers. Moreover, the Eu(III) and Dy(III) complexes display characteristic luminescence emission in the visible regions. - Graphical abstract: A new family of lanthanide-organic frameworks incorporating multi-donor twisted ligand has been fabricated successfully, and has been characterized systematically. The complexes 1–5 are isostructural, and all feather three dimensional (3D) frameworks based on the interconnection of 1D double stride chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 2+} basic carboxylate as secondary building unit (SBU). Display Omitted - Highlights: • New family of lanthanide–organic coordination polymers incorporating multifunctional N-hetrocyclic dicarboxylate ligand has been fabricated. • They have been characterized systematically. • They all feather three dimensional frameworks based on the binuclear moiety of [Ln{sub 2}(Hdpp){sub 2}]{sup 2+}. • The Eu(III) and Dy(III) analogues exhibit intense photoluminescence.

  5. Ferricyanide-based analysis of aqueous lignin suspension revealed sequestration of water-soluble lignin moieties

    OpenAIRE

    Joshua, CJ; Simmons, BA; Singer, SW

    2016-01-01

    © 2016 The Royal Society of Chemistry. This study describes the application of a ferricyanide-based assay as a simple and inexpensive assay for rapid analysis of aqueous lignin samples. The assay measures the formation of Prussian blue from the redox reaction between a mixture of potassium ferricyanide and ferric chloride, and phenolic hydroxyl groups of lignin or lignin-derived phenolic moieties. This study revealed that soluble lignin moieties exhibited stronger ferricyanide reactivity than...

  6. Selective tumor cell targeting by the disaccharide moiety of bleomycin.

    Science.gov (United States)

    Yu, Zhiqiang; Schmaltz, Ryan M; Bozeman, Trevor C; Paul, Rakesh; Rishel, Michael J; Tsosie, Krystal S; Hecht, Sidney M

    2013-02-27

    In a recent study, the well-documented tumor targeting properties of the antitumor agent bleomycin (BLM) were studied in cell culture using microbubbles that had been derivatized with multiple copies of BLM. It was shown that BLM selectively targeted MCF-7 human breast carcinoma cells but not the "normal" breast cell line MCF-10A. Furthermore, it was found that the BLM analogue deglycobleomycin, which lacks the disaccharide moiety of BLM, did not target either cell line, indicating that the BLM disaccharide moiety is necessary for tumor selectivity. Not resolved in the earlier study were the issues of whether the BLM disaccharide moiety alone is sufficient for tumor cell targeting and the possible cellular uptake of the disaccharide. In the present study, we conjugated BLM, deglycoBLM, and BLM disaccharide to the cyanine dye Cy5**. It was found that the BLM and BLM disaccharide conjugates, but not the deglycoBLM conjugate, bound selectively to MCF-7 cells and were internalized. The same was also true for the prostate cancer cell line DU-145 (but not for normal PZ-HPV-7 prostate cells) and for the pancreatic cancer cell line BxPC-3 (but not for normal SVR A221a pancreas cells). The targeting efficiency of the disaccharide was only slightly less than that of BLM in MCF-7 and DU-145 cells and comparable to that of BLM in BxPC-3 cells. These results establish that the BLM disaccharide is both necessary and sufficient for tumor cell targeting, a finding with obvious implications for the design of novel tumor imaging and therapeutic agents.

  7. Metallacyclopentadienes: structural features and coordination in transition metal complexes

    International Nuclear Information System (INIS)

    Dolgushin, Fedor M; Yanovsky, Aleksandr I; Antipin, Mikhail Yu

    2004-01-01

    Results of structural studies of polynuclear transition metal complexes containing the metallacyclopentadiene fragment are overviewed. The structural features of the complexes in relation to the nature of the substituents in the organic moiety of the metallacycles, the nature of the transition metals and their ligand environment are analysed. The main structural characteristics corresponding to different modes of coordination of metallacyclopentadienes to one or two additional metal centres are revealed.

  8. Selfassembly of gold nanoparticles onto the surface of multiwall carbon nanotubes functionalized with mercaptobenzene moieties

    International Nuclear Information System (INIS)

    Shi Jin; Wang Zhe; Li Hulin

    2006-01-01

    We have developed a new and effective method to robustly self-assemble gold nanoparticles onto the surface of multiwall carbon nanotubes (MWNTs) functionalized with mercaptobenzene moieties. Fourier transform infrared and electron diffraction spectroscopy were used to verify whether or not the mercaptobenzene moieties have been attached to the π-conjugated body of MWNTs. Transmission electron microscope images give direct evidences for the success of selfassembly of gold nanoparticles onto the functionalized MWNTs

  9. Evolutionary convergence in the biosyntheses of the imidazole moieties of histidine and purines.

    Directory of Open Access Journals (Sweden)

    Alberto Vázquez-Salazar

    Full Text Available The imidazole group is an ubiquitous chemical motif present in several key types of biomolecules. It is a structural moiety of purines, and plays a central role in biological catalysis as part of the side-chain of histidine, the amino acid most frequently found in the catalytic site of enzymes. Histidine biosynthesis starts with both ATP and the pentose phosphoribosyl pyrophosphate (PRPP, which is also the precursor for the de novo synthesis of purines. These two anabolic pathways are also connected by the imidazole intermediate 5-aminoimidazole-4-carboxamide ribotide (AICAR, which is synthesized in both routes but used only in purine biosynthesis. Rather surprisingly, the imidazole moieties of histidine and purines are synthesized by different, non-homologous enzymes. As discussed here, this phenomenon can be understood as a case of functional molecular convergence.In this work, we analyze these polyphyletic processes and argue that the independent origin of the corresponding enzymes is best explained by the differences in the function of each of the molecules to which the imidazole moiety is attached. Since the imidazole present in histidine is a catalytic moiety, its chemical arrangement allows it to act as an acid or a base. On the contrary, the de novo biosynthesis of purines starts with an activated ribose and all the successive intermediates are ribotides, with the key β-glycosidic bondage joining the ribose and the imidazole moiety. This prevents purine ribonucleotides to exhibit any imidazole-dependent catalytic activity, and may have been the critical trait for the evolution of two separate imidazole-synthesizing-enzymes. We also suggest that, in evolutionary terms, the biosynthesis of purines predated that of histidine.As reviewed here, other biosynthetic routes for imidazole molecules are also found in extant metabolism, including the autocatalytic cyclization that occurs during the formation of creatinine from creatine phosphate

  10. Arsenic moiety in gallium arsenide is responsible for neuronal apoptosis and behavioral alterations in rats

    International Nuclear Information System (INIS)

    Flora, Swaran J.S.; Bhatt, Kapil; Mehta, Ashish

    2009-01-01

    Gallium arsenide (GaAs), an intermetallic semiconductor finds widespread applications in high frequency microwave and millimeter wave, and ultra fast supercomputers. Extensive use of GaAs has led to increased exposure to humans working in semiconductor industry. GaAs has the ability to dissociate into its constitutive moieties at physiological pH and might be responsible for the oxidative stress. The present study was aimed at evaluating, the principle moiety (Ga or As) in GaAs to cause neurological dysfunction based on its ability to cause apoptosis, in vivo and in vitro and if this neuronal dysfunction translated to neurobehavioral changes in chronically exposed rats. Result indicated that arsenic moiety in GaAs was mainly responsible for causing oxidative stress via increased reactive oxygen species (ROS) and nitric oxide (NO) generation, both in vitro and in vivo. Increased ROS further caused apoptosis via mitochondrial driven pathway. Effects of oxidative stress were also confirmed based on alterations in antioxidant enzymes, GPx, GST and SOD in rat brain. We noted that ROS induced oxidative stress caused changes in the brain neurotransmitter levels, Acetylcholinesterase and nitric oxide synthase, leading to loss of memory and learning in rats. The study demonstrates for the first time that the slow release of arsenic moiety from GaAs is mainly responsible for oxidative stress induced apoptosis in neuronal cells causing behavioral changes.

  11. Design of Thermochromic Polynorbornene Bearing Spiropyran Chromophore Moieties: Synthesis, Thermal Behavior and Dielectric Barrier Discharge Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Saleh A. Ahmed

    2017-11-01

    Full Text Available A new class of thermochromic polynorbornene with pendent spiropyran moieties has been synthesized. Functionalization of norbornene monomers with spirobenzopyran moieties has been achieved using Steglich esterification. These new monomeric materials were polymerized via Ring Opening Metathesis Polymerization (ROMP. In spite of their poor solubility, polynorbornenes with spirobenzopyran exhibited thermochromic behavior due to the conversion of their closed spiropyran moieties to the open merocyanine form. Moreover, these polymers displayed bathochromic shifts in their optical response, which was attributed to the J-aggregation of the attached merocyanine moieties that were associated with their high concentration in the polymeric chain. The surface of the obtained polymers was exposed to atmospheric pressure air Dielectric Barrier Discharge (DBD plasma system, which resulted in the reduction of the surface porosity and converted some surface area into completely non-porous regions. Moreover, the plasma system created some areas with highly ordered J-aggregates of the merocyanine form in thread-like structures. This modification of the polymers’ morphology may alter their applications and allow for these materials to be potential candidates for new applications, such as non-porous membranes for reverse osmosis, nanofiltration, or molecular separation in the gas phase.

  12. A Modified P1 Moiety Enhances in vitro Antiviral Activity against Various Multi-Drug-Resistant HIV-1 Variants and in vitro CNS Penetration Properties of a Novel Nonpeptidic Protease Inhibitor, GRL-10413

    Energy Technology Data Exchange (ETDEWEB)

    Amano, Masayuki; Salcedo-Gómez, Pedro Miguel; Zhao, Rui; Yedidi, Ravikiran S.; Das, Debananda; Bulut, Haydar; Delino, Nicole S.; Sheri, Venkata Reddy; Ghosh, Arun K.; Mitsuya, Hiroaki (Kumamoto); (NIH); (Purdue)

    2016-09-12

    We here report that GRL-10413, a novel non-peptidic HIV-1 protease inhibitor (PI) containing a modified P1 moiety and a sulfonamide isostere, is highly active against laboratory HIV-1 strains and primary clinical isolates (EC50: 0.00035 - 0.0018 μM) with minimal cytotoxicity (CC50: 35.7 μM). GRL-10413 blocked the infectivity and replication of HIV-1NL4-3variants selected by up to 5 μM concentrations of atazanavir, lopinavir, or amprenavir (EC50: 0.0021 - 0.0023 μM). GRL-10413 also maintained its strong antiviral activity against multi-drug-resistant clinical HIV-1 variants isolated from patients, who no longer responded to various antiviral regimens after long-term antiretroviral therapy. The development of resistance against GRL-10413 was significantly delayed compared to that of APV. In addition, GRL-10413 showed a favorable central nervous system (CNS) penetration property as assessed with anin vitroblood brain barrier (BBB) reconstruction system. Analysis of the crystal structure of HIV-1 protease in complex with GRL-10413 demonstrated that the modified P1 moiety of GRL-10413 has a greater hydrophobic surface area and makes greater van der Waals contacts with active-site amino acids of protease than in the case of darunavir. Moreover, the chlorine substituent in the P1 moiety interacts with protease in two distinct configurations. The present data demonstrate that GRL-10413 has desirable features for treating patients infected with wild-type and/or multi-drug-resistant HIV-1 variants with favorable CNS-penetration capability and that the newly modified P1-moiety may confer desirable features in designing novel anti-HIV-1 PIs.

  13. Stabilization of liquid crystal dispersion by nonionic surfactant/acrylamide copolymer containing hydrophobic moieties

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.J.; Kim, M.H.; Lee, J.R. [Korea Research Institute of Chemical Technology, Taejon (Korea)

    1999-07-01

    The effect of nonionic surfactant (H(OCH){sub 2}-OC{sub 6}H{sub 4}-C{sub 9}H{sub 19}, NP-8) and acrylamide copolymer containing nonylphenyl groups as hydrophobic moieties on the stabilization of liquid crystal (LC)-in-water dispersion has been studied. According to cloud point and adsorption measurements, the hydrophobically strong interaction between NP-8 and the nonylphenol moieties is formed. And the addition of surfactant increases the stability of LC dispersion and improve the electrooptical properties of the nematic curvilinear aligned phase (NCAP) composite film. It is due to the presence of surfactant which allows the formation of nonpolar microenvironment in the round of LC droplet and finally reduces the anchoring effect between LC and the polymeric wall. 21 refs., 8 figs.

  14. Iptycene synthesis: A new method for attaching a 2,3-anthracene moiety to the 9,10-positions of another anthracene moiety - Exceptional conditions for a Lewis acid catalyzed Diels-Alder reaction

    Science.gov (United States)

    Chen, Yong-Shing; Hart, Harold

    1989-01-01

    An efficient three-step method for appending a 2,3-anthracene moiety to the 9,10-positions of an existing anthracene moiety is described. The first step uses excess 1,4-anthraquinone (3 equiv) and aluminum chloride (6 equiv) to obtain the anthracene-quinone cycloadduct (omission of the AlCl3 resulted in no adduct). The resulting diketone was reduced to the corresponding diol (excess LiAlH4), which was dehydrated to the arene with phosphorus oxychloride and pyridine. Specific examples include the preparation of heptipycene 8 from pentiptycene 6 (66 percent overall yield) and a similar conversion of 8 to the noniptycene 13 (75 percent overall yield). The methodology led to a markedly improved synthesis of tritriptycene 9 and the first synthesis of undecaiptycene 14.

  15. Novel immobilization of a quaternary ammonium moiety on keratin fibers for medical applications.

    Science.gov (United States)

    Yu, Dan; Cai, Jackie Y; Liu, Xin; Church, Jeffrey S; Wang, Lijing

    2014-09-01

    This paper introduces a new approach for immobilizing a quaternary ammonium moiety on a keratinous substrate for enhanced medical applications. The method involves the generation of thiols by controlled reduction of cystine disulfide bonds in the keratin, followed by reaction with [2-(acryloyloxy)ethyl]trimethylammonium chloride through thiol-ene click chemistry. The modified substrate was characterized with Raman and infrared spectroscopy, and assessed for its antibacterial efficacy and other performance changes. The results have demonstrated that the quaternary ammonium moiety has been effectively attached onto the keratin structure, and the resultant keratin substrate exhibits a multifunctional effect including antibacterial and antistatic properties, improved liquid moisture management property, improved dyeability and a non-leaching characteristic of the treated substrate. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  16. Transformation of ranitidine during water chlorination and ozonation: Moiety-specific reaction kinetics and elimination efficiency of NDMA formation potential.

    Science.gov (United States)

    Jeon, Dahee; Kim, Jisoo; Shin, Jaedon; Hidayat, Zahra Ramadhany; Na, Soyoung; Lee, Yunho

    2016-11-15

    Ranitidine can produce high yields of N-nitrosodimethylamine (NDMA) upon chloramination and its presence in water resources is a concern for water utilities using chloramine disinfection. This study assessed the efficiency of water chlorination and ozonation in transforming ranitidine and eliminating its NDMA formation potential (NDMA-FP) by determining moiety-specific reaction kinetics, stoichiometric factors, and elimination levels in real water matrices. Despite the fact that chlorine reacts rapidly with the acetamidine and thioether moieties of ranitidine (k>10(8)M(-1)s(-1) at pH 7), the NDMA-FP decreases significantly only when chlorine reacts with the less reactive tertiary amine (k=3×10(3)M(-1)s(-1) at pH 7) or furan moiety (k=81M(-1)s(-1) at pH 7). Ozone reacts rapidly with all four moieties of ranitidine (k=1.5×10(5)-1.6×10(6)M(-1)s(-1) at pH 7) and its reaction with the tertiary amine or furan moiety leads to complete elimination of the NDMA-FP. Treatments of ranitidine-spiked real water samples have shown that ozonation can efficiently deactivate ranitidine in water and wastewater treatment, while chlorination can be efficient for water containing low concentration of ammonia. This result can be applied to the other structurally similar, potent NDMA precursors. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Statistical mechanical model of gas adsorption in porous crystals with dynamic moieties.

    Science.gov (United States)

    Simon, Cory M; Braun, Efrem; Carraro, Carlo; Smit, Berend

    2017-01-17

    Some nanoporous, crystalline materials possess dynamic constituents, for example, rotatable moieties. These moieties can undergo a conformation change in response to the adsorption of guest molecules, which qualitatively impacts adsorption behavior. We pose and solve a statistical mechanical model of gas adsorption in a porous crystal whose cages share a common ligand that can adopt two distinct rotational conformations. Guest molecules incentivize the ligands to adopt a different rotational configuration than maintained in the empty host. Our model captures inflections, steps, and hysteresis that can arise in the adsorption isotherm as a signature of the rotating ligands. The insights disclosed by our simple model contribute a more intimate understanding of the response and consequence of rotating ligands integrated into porous materials to harness them for gas storage and separations, chemical sensing, drug delivery, catalysis, and nanoscale devices. Particularly, our model reveals design strategies to exploit these moving constituents and engineer improved adsorbents with intrinsic thermal management for pressure-swing adsorption processes.

  18. Structural effects of a light emitting copolymer having perylene moieties in the side chain on the electroluminescent characteristics

    International Nuclear Information System (INIS)

    Lee, Chang Ho; Ryu, Seung Hoon; Jang, Hee Dong; Oh, Se Young

    2004-01-01

    We have synthesized a novel side chain light emitting copolymer. The side chain light emitting copolymer has a perylene moiety as an emitting unit and methylmethacrylate (MMA) as a spacer to decrease the concentration quenching of light emitting site in the polymer intrachain. These polymers are very soluble in most organic solvents such as monochlorobenzene, tetrahydrofuran, chloroform and benzene. The single-layered electroluminescent (EL) device consisting of ITO/carrier transporting copolymer and light emitting copolymer/Al was manufactured. The carrier transporting copolymer has triphenylamine moiety as a hole transporting unit and triazine moiety as an electron transporting unit in the polymer side chain. This device exhibits maximum external quantum efficiency when the MMA contents of light emitting copolymer is 30 wt.%. In particular, the device emits more blue light as MMA contents increase

  19. High-efficiency red-light emission from polyfluorenes grafted with cyclometalated iridium complexes and charge transport moiety.

    Science.gov (United States)

    Chen, Xiwen; Liao, Jin-Long; Liang, Yongmin; Ahmed, M O; Tseng, Hao-En; Chen, Show-An

    2003-01-22

    We report a new route for the design of electroluminescent polymers by grafting high-efficiency phosphorescent organometallic complexes as dopants and charge transport moieties onto alky side chains of fully conjugated polymers for polymer light-emitting diodes (PLED) with single layer/single polymers. The polymer system studied involves polyfluorene (PF) as the base conjugated polymer, carbazole (Cz) as the charge transport moiety and a source for green emission by forming an electroplex with the PF main chain, and cyclometalated iridium (Ir) complexes as the phosphorescent dopant. Energy transfer from the green Ir complex or an electroplex formed between the fluorene main chain and side-chain carbazole moieties, in addition to that from the PF main chain, to the red Ir complex can significantly enhance the device performance, and a red light-emitting device with the high efficiency 2.8 cd/A at 7 V and 65 cd/m2, comparable to that of the same Ir complex-based OLED, and a broad-band light-emitting device containing blue, green, and red peaks (2.16 cd/A at 9 V) are obtained.

  20. Synthesis, Antiviral Bioactivity of Novel 4-Thioquinazoline Derivatives Containing Chalcone Moiety

    Directory of Open Access Journals (Sweden)

    Zhihua Wan

    2015-06-01

    Full Text Available A series of novel 4-thioquinazoline derivatives containing chalcone moiety were designed, synthesized and systematically evaluated for their antiviral activity against TMV. The bioassay results showed that most of these compounds exhibited moderate to good anti-TMV activity. In particular, compounds M2 and M6 possessed appreciable protection activities against TMV in vivo, with 50% effective concentration (EC50 values of 138.1 and 154.8 μg/mL, respectively, which were superior to that of Ribavirin (436.0 μg/mL. The results indicated that chalcone derivatives containing 4-thioquinazoline moiety could effectively control TMV. Meanwhile, the structure-activity relationship (SAR of the target compounds, studied using the three-dimensional quantitative structure-activity relationship (3D-QSAR method of comparative molecular field analysis (CoMFA based on the protection activities against TMV, demonstrated that the CoMFA model exhibited good predictive ability with the cross-validated q2 and non-cross-validated r2 values of 0.674 and 0.993, respectively. Meanwhile, the microscale thermophoresis (MST experimental showed that the compound M6 may interaction with the tobacco mosaic virus coat protein (TMV CP.

  1. Primary structure of the oligosaccharide moiety of hemocyanin from the scorpion Androctonus australis

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Debeire, P.; Montreuil, J.; Goyffon, M.; Kuik, J.A. van; Halbeek, H. van

    1986-01-01

    Hemocyanin, the copper-containing glycoprotein that serves as an oxygen carrier in the hemolymph of some arthropods and molluscs, was obtained from the blood of the scorpion Androctonus australis. Sugar analysis of the glycoprotein revealed that its carbohydrate moiety is of the N-glycosylic type.

  2. Flexible Enantioselectivity of Tryptophanase Attributable to Benzene Ring in Heterocyclic Moiety of D-Tryptophan

    Directory of Open Access Journals (Sweden)

    Akihiko Shimada

    2012-05-01

    Full Text Available The invariance principle of enzyme enantioselectivity must be absolute because it is absolutely essential to the homochiral biological world. Most enzymes are strictly enantioselective, and tryptophanase is one of the enzymes with extreme absolute enantioselectivity for L-tryptophan. Contrary to conventional knowledge about the principle, tryptophanase becomes flexible to catalyze D-tryptophan in the presence of diammonium hydrogenphosphate. Since D-amino acids are ordinarily inert or function as inhibitors even though they are bound to the active site, the inhibition behavior of D-tryptophan and several inhibitors involved in this process was examined in terms of kinetics to explain the reason for this flexible enantioselectivity in the presence of diammonium hydrogenphosphate. Diammonium hydrogenphosphate gave tryptophanase a small conformational change so that D-tryptophan could work as a substrate. As opposed to other D-amino acids, D-tryptophan is a very bulky amino acid with a benzene ring in its heterocyclic moiety, and so we suggest that this structural feature makes the catalysis of D-tryptophan degradation possible, consequently leading to the flexible enantioselectivity. The present results not only help to understand the mechanism of enzyme enantioselectivity, but also shed light on the origin of homochirality.

  3. Synthesis and Antifungal Activity of Novel Sulfone Derivatives Containing 1,3,4-Oxadiazole Moieties

    Directory of Open Access Journals (Sweden)

    Maoguo Tong

    2011-11-01

    Full Text Available A series of new sulfone compounds containing 1,3,4-oxadiazole moieties were synthesized. The structures of these compounds were confirmed by spectroscopic data (IR, 1H- and 13C-NMR and elemental analyses. Antifungal tests indicated that all the title compounds exhibited good antifungal activities against eight kinds of plant pathogenic fungi, and some showed superiority over the commercial fungicide hymexazol. Among them, compounds 5d, 5e, 5f, and 5i showed prominent activity against B. cinerea, with determined EC50 values of 5.21 μg/mL, 8.25 µg/mL, 8.03 µg/mL, and 21.00 µg/mL, respectively. The present work demonstrates that sulfone derivatives such as 5d containing a 1,3,4-oxadiazole moiety can be used as possible lead compounds for the development of potential agrochemicals.

  4. New Microporous Polymer Electrolyte Based on Polysiloxane Grafted with Imidazolium Iodide Moieties for DSSC

    Directory of Open Access Journals (Sweden)

    Yan Yang

    2011-01-01

    Full Text Available Two types of polysiloxane grafted with different ratio of imidazolium iodide moieties (IL-SiO2 have been synthesized to develop a micro-porous polymer electrolyte for quasi-solid-state dye-sensitized solar cells. The samples were characterized by 1HNMR, FT-IR spectrum, XRD, TEM and SEM, respectively. Moreover, the ionic conductivity of the electrolytes was measured by electrochemical workstation. Nanostructured polysiloxane containing imidazolium iodide showed excellent compatibility with organic solvent and polymer matrix for its ionic liquid characteristics. Increasing the proportion of imidazolium iodide moieties in polysiloxane improved the electrochemical behavior of the gel polymer electrolyte. A dye-sensitized solar cell with gel polymer electrolyte yielded an open-circuit voltage of 0.70 V, short-circuit current of 11.19 mA cm−2, and the conversion efficiency of 3.61% at 1 sun illumination.

  5. The effect of distribution of monomer moiety on the pH response and mechanical properties of poly(acrylonitrile-co-acrylic acid) copolymers

    International Nuclear Information System (INIS)

    Sahoo, Anasuya; Jassal, Manjeet; Agrawal, Ashwini K

    2010-01-01

    The pH response and mechanical properties of copolymer-based hydrogels such as poly(acrylonitrile-co-acrylic acid) are usually attributed to their chemical composition. In this study, it has been shown that the architecture of the polymer chains, i.e. the distribution of comonomers in the macromolecules, also plays a major role in controlling these properties. A series of four poly(acrylonitrile-co-acrylic acids) with fixed composition (i.e. ∼30 mol% acrylic acid moieties) were synthesized, where the block lengths of both AN (acrylonitrile) and AAc (acrylic acid) moieties in the copolymers were varied by controlling the feeding pattern of the monomers during free radical copolymerization. These copolymers were then converted into fine fibers of the same dimensions. The monomer distribution in the four copolymers was estimated using quantitative carbon 13 C nuclear magnetic resonance (NMR) and related to the mechanical and pH response properties of the resultant fibers. The pH response of the fibers with similar composition increased dramatically as the block length of the AAc moiety was increased, while the mechanical properties increased as a direct function of the block length of the AN moieties. The fiber's response at pH 10 in terms of the change in length increased by ∼four times while its response rate increased by ∼50 times with the increase in block length of the AAc moiety. On the other hand, the tensile properties and retractive stress increased by ∼four times with the increase in the block length of the AN moiety

  6. The effect of distribution of monomer moiety on the pH response and mechanical properties of poly(acrylonitrile-co-acrylic acid) copolymers

    Science.gov (United States)

    Sahoo, Anasuya; Jassal, Manjeet; Agrawal, Ashwini K.

    2010-02-01

    The pH response and mechanical properties of copolymer-based hydrogels such as poly(acrylonitrile-co-acrylic acid) are usually attributed to their chemical composition. In this study, it has been shown that the architecture of the polymer chains, i.e. the distribution of comonomers in the macromolecules, also plays a major role in controlling these properties. A series of four poly(acrylonitrile-co-acrylic acids) with fixed composition (i.e. ~30 mol% acrylic acid moieties) were synthesized, where the block lengths of both AN (acrylonitrile) and AAc (acrylic acid) moieties in the copolymers were varied by controlling the feeding pattern of the monomers during free radical copolymerization. These copolymers were then converted into fine fibers of the same dimensions. The monomer distribution in the four copolymers was estimated using quantitative carbon 13C nuclear magnetic resonance (NMR) and related to the mechanical and pH response properties of the resultant fibers. The pH response of the fibers with similar composition increased dramatically as the block length of the AAc moiety was increased, while the mechanical properties increased as a direct function of the block length of the AN moieties. The fiber's response at pH 10 in terms of the change in length increased by ~four times while its response rate increased by ~50 times with the increase in block length of the AAc moiety. On the other hand, the tensile properties and retractive stress increased by ~four times with the increase in the block length of the AN moiety.

  7. Preservation of peptide moieties in three Spanish sulfur-rich Tertiary kerogens

    Energy Technology Data Exchange (ETDEWEB)

    Rio, J.C. del [Consejo Superior de Investigaciones Cientificas, Seville (Spain). Inst. de Recursos Naturales y Agrobiologia; Olivella, M.A.; Heras, F.X.D. de las [Escola Universitaria Politecnica de Manresa, Catalonia (Spain); Knicker, H. [Technische Universitaet Muenchen (Germany). Lehrstuhl fuer Bodenkunde

    2004-09-01

    Thermochemolysis with tetramethylammonium hydroxide (TMAH) and solid-state {sup 15}N NMR were utilized for the characterization of refractory organic nitrogen in Tertiary Spanish kerogens. The samples included sulfur-rich oil shales from the Ribesalbes (Serravallian), Libros (Tortonian) and Cerdanya (Tortonian) basins. Analysis using solid state {sup 15}N NMR showed that part of the refractory nitrogen in the kerogens corresponds to amide groups. Moreover, the release of amino acid derivatives after pyrolysis in the presence of TMAH indicated that this amide-N arose from peptide moieties. The amino acids released from the kerogens were dominated by high amounts of glycine and alanine. Minor amounts of aspartic acid, serine, {alpha}-aminobutyric acid and other unidentified amino acids were also detected. Because proteinaceous structures, including small peptides, are generally considered as being highly sensitive to diagenetic degradation, encapsulation of labile peptide material into aliphatic structures in S-rich kerogens (probably via lipid sulfurization) has been proposed to explain the survival of these moieties. Substantial amounts of fatty acids (as methyl esters) were also released from all the kerogens after pyrolysis/TMAH, indicating their highly aliphatic character. The production of both fatty acids and amino acids from the kerogens supports the encapsulation process. (author)

  8. Synthesis of polynorbornene with pendant moiety bearing azide and terminal alkyne groups

    Institute of Scientific and Technical Information of China (English)

    Ze Zhang; Zhi Wei Peng; Kun Zeng Fan

    2011-01-01

    A powerful approach to the synthesis of an unprecedented polynorbornene with pendant moiety bearing azide and terminal alkyne groups is developed. Two key intermediates, namely, 3-azido-5-(2-(trimethylsilyl)ethynyl) benzyl alcohol and 4-(4-aza-tricyclo [5.2.1.02.6]dec-8-en-4-yl) benzoic acid, were optimally synthesized for convergent synthesis of the corresponding monomer.

  9. Donor-π-Acceptor Polymer with Alternating Triarylborane and Triphenylamine Moieties.

    Science.gov (United States)

    Li, Haiyan; Jäkle, Frieder

    2010-05-12

    A luminescent main chain donor-π-acceptor-type polymer (4) was prepared via organometallic polycondensation reaction followed by post modification. With both electron-rich amine and electron-deficient borane moieties embedded in the main chain, 4 exhibits an interesting ambipolar character: it can be reduced and oxidized electrochemically at moderate potentials and shows a strong solvatochromic effect in the emission spectra. Complexation studies show that 4 selectively binds to fluoride and cyanide; quantitative titration with cyanide reveals a two-step binding process. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Decisive Interactions between the Heterocyclic Moiety and the Cluster Observed in Polyoxometalate-Surfactant Hybrid Crystals

    Directory of Open Access Journals (Sweden)

    Saki Otobe

    2015-04-01

    Full Text Available Inorganic-organic hybrid crystals were successfully obtained as single crystals by using polyoxotungstate anion and cationic dodecylpyridazinium (C12pda and dodecylpyridinium (C12py surfactants. The decatungstate (W10 anion was used as the inorganic component, and the crystal structures were compared. In the crystal comprising C12pda (C12pda-W10, the heterocyclic moiety directly interacted with W10, which contributed to a build-up of the crystal structure. On the other hand, the crystal consisting of C12py (C12py-W10 had similar crystal packing and molecular arrangement to those in the W10 crystal hybridized with other pyridinium surfactants. These results indicate the significance of the heterocyclic moiety of the surfactant to construct hybrid crystals with polyoxometalate anions.

  11. The effect of intramolecular donor–acceptor moieties with donor–π-bridge–acceptor structure on the solar photovoltaic performance

    Directory of Open Access Journals (Sweden)

    T. L. Wang

    2015-10-01

    Full Text Available A series of intramolecular donor–acceptor polymers containing different contents of (E-1-(2-ethylhexyl-6,9-dioctyl-2-(2-(thiophen-3-ylvinyl-1H-phenanthro[9,10-d]imidazole (thiophene-DOPI moiety and 4,4-diethylhexylcyclopenta[ 2,1-b:3,4-b']dithiophene (CPDT unit was synthesized via Grignard metathesis (GRIM polymerization. The synthesized random copolymers and homopolymer of thiophene-DOPI contain the donor–π-bridge–acceptor conjugated structure to tune the absorption spectra and energy levels of the resultant polymers. UV-vis spectra of the three polymer films exhibit panchromatic absorptions ranging from 300 to 1100 nm and low band gaps from 1.38 to 1.51 eV. It is found that more thiophene-DOPI moieties result in the decrease of band gap and lower the highest occupied molecular orbital (HOMO and lowest unoccupied molecular orbital (LUMO values of polymers. Photovoltaic performance results indicate that if the content of the intramolecular donor–acceptor moiety is high enough, the copolymer structure may be better than homopolymer due to more light-harvesting afforded by both monomer units.

  12. Different Steric-Twist-Induced Ternary Memory Characteristics in Nonconjugated Copolymers with Pendant Naphthalene and 1,8-Naphthalimide Moieties.

    Science.gov (United States)

    Wang, Ming; Li, Zhuang; Li, Hua; He, Jinghui; Li, Najun; Xu, Qingfeng; Lu, Jianmei

    2017-10-18

    Herein, novel random copolymers PMNN and PMNB were designed and synthesized, and the memory devices Al/PMNN and PMNB/ITO both exhibited ternary memory performance. The switching voltages of the OFF-ON1 and ON1-ON2 transitions for both memory devices are around -2.0 and -3.5 V, respectively, and the ON1/OFF, ON2/ON1 current ratios are both up to 10 3 . The observed tristable electrical conductivity switching could be attributed to field-induced conformational ordering of the naphthalene rings in the side chains, and subsequent charge trapping by 1,8-naphthalimide moieties. More interestingly, by adjusting the connection sites of 1,8-naphthalimide moieties to tune the steric-twist effect, different memory properties were achieved (PMNN showed nonvolatile write once, read many (WORM) memory behavior, whereas PMNB showed volatile static RAM (SRAM) memory behavior). This result will offer a guideline for the design of different high-performance multilevel memory devices by tuning the steric effects of the chemical moieties. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Synthesis and Characterization of Poly (ether imide)s Containing Phthalazinone and Isopropyl Moieties

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel poly(ether imide)s containing phthalazinone and isopropyl moieties derived from 2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl]-phthalazin-l-one and bisphenol-A diphthalic anhydride was synthesized by one-step solution condensation polymerization in m-cresol. The polymer was characterized by FTIR, NMR, molecular weights, glass transition temperature,thermal degradation temperature and WAXD.

  14. Robot-assisted pyeloplasty for pelvi-ureteric junction obstruction of lower moiety in partial duplex system: A technical challenge

    Directory of Open Access Journals (Sweden)

    Girdhar S Bora

    2016-01-01

    Full Text Available Management of pelvi-ureteric junction obstruction (PUJO in a duplex system is technically challenging as dissection at the pelvis may jeopardize the vascularity of the normal moiety ureter. Anastomosing the pelvis to the one single ureter will have a risk of future development of stricture which then will risk both the moieties. Robotic assistance enables appropriate tissue dissection; minimal handling of normal ureter and precision in suturing, overcoming the potential challenges involved in the minimally invasive management of such complex cases. We report the feasibility and efficacy of robot-assisted laparoscopic pyeloplasty in such case.

  15. Syntehsis and antiproliferative activities of chloropyridazine derivatives retain alkylsulfonyl moiety

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chae Won; Park, Myung Sook [College of Pharmacy, Duksung Women' s University, Seoul (Korea, Republic of)

    2016-11-15

    Some chloropyridazine derivatives have shown interesting pharmacodynamics properties in terms of antioxidant and anti-human rotavirus (HRV) activities (Figure 1). To date, however, no study has evaluated the antiproliferative effects of chloropyridazines in other types of human cancer cells. In conclusion, we designed and synthesized a total of five groups of alkoxy-(or alkylthio-, alkylselenyl-, alkylsufinyl alkylsulfonyl-)chloropyridazines, and their antiproliferative activity was evaluated in the human cancer cell lines. IC{sub 50} values showed that the alkylsulfonylchloropyridazine compounds exhibited more active than the other four groups having alkoxy, alkylthio, alkylselenyl, alkylsulfinyl moieties against MCF-7 and Hep2B Cells.

  16. Syntehsis and antiproliferative activities of chloropyridazine derivatives retain alkylsulfonyl moiety

    International Nuclear Information System (INIS)

    Kim, Chae Won; Park, Myung Sook

    2016-01-01

    Some chloropyridazine derivatives have shown interesting pharmacodynamics properties in terms of antioxidant and anti-human rotavirus (HRV) activities (Figure 1). To date, however, no study has evaluated the antiproliferative effects of chloropyridazines in other types of human cancer cells. In conclusion, we designed and synthesized a total of five groups of alkoxy-(or alkylthio-, alkylselenyl-, alkylsufinyl alkylsulfonyl-)chloropyridazines, and their antiproliferative activity was evaluated in the human cancer cell lines. IC_5_0 values showed that the alkylsulfonylchloropyridazine compounds exhibited more active than the other four groups having alkoxy, alkylthio, alkylselenyl, alkylsulfinyl moieties against MCF-7 and Hep2B Cells

  17. Metallocene-based antimalarials: an exploration into the influence of the ferrocenyl moiety on in vitro antimalarial activity in chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum.

    Science.gov (United States)

    Blackie, Margaret A L; Beagley, Paul; Croft, Simon L; Kendrick, Howard; Moss, John R; Chibale, Kelly

    2007-10-15

    To establish the role of the ferrocenyl moiety in the antiplasmodial activity of ferroquine, compounds in which this moiety is replaced by the corresponding ruthenium-based moieties were synthesized and evaluated. In both the sensitive (D10) and resistant (K1) strains of Plasmodium falciparum, ruthenoquine analogues showed comparable potency to ferroquine. This suggests that a probable role of the ferrocenyl fragment is to serve simply as a hydrophobic spacer group. In addition, ferroquine analogues with different aromatic substituents were synthesized and evaluated. Unexpectedly high activity for quinoline compounds lacking the 7-chloro substituent suggests the ferrocenyl moiety may have an additive and/or synergistic effect.

  18. Difluorobenzothiadiazole based two-dimensional conjugated polymers with triphenylamine substituted moieties as pendants for bulk heterojunction solar cells

    Directory of Open Access Journals (Sweden)

    W. H. Lee

    2017-11-01

    Full Text Available Three donor/acceptor (D/A-type two-dimensional polythiophenes (PTs; PBTFA13, PBTFA12, PBTFA11 featuring difluorobenzothiadiazole (DFBT derivatives as the conjugated (acceptor units in the polymer backbone and tertbutyl–substituted triphenylamine (tTPA-containing moieties as (donor pendants have been synthesized and characterized. These PTs exhibited good thermal stabilities, broad absorption spectra, and narrow optical band gaps. The cutoff wavelength of the UV–Vis absorption band was red-shifted upon increasing the content of the DFBT units in the PTs. Bulk heterojunction solar cells having an active layer comprising blends of the PTs and fullerene derivatives [6,6] phenyl-C61/71-butyric acid methyl ester (PC61BM/PC71BM were fabricated; their photovoltaic performance was strongly dependent on the content of the DFBT derivative in the PT. Incorporating a suitable content of the DFBT derivative in the polymer backbone enhanced the solar absorption ability and conjugation length of the PTs. The photovoltaic properties of the PBTFA13-based solar cells were superior to those of the PBTFA11- and PBTFA12-based solar cells.

  19. Hydrophilization of poly(caprolactone copolymers through introduction of oligo(ethylene glycol moieties.

    Directory of Open Access Journals (Sweden)

    Jonathan J Wurth

    Full Text Available In this study, a new family of poly(ε-caprolactone (PCL copolymers that bear oligo(ethylene glycol (OEG moieties is described. The synthesis of three different oligo(ethylene glycol functionalized epoxide monomers derived from 2-methyl-4-pentenoic acid, and their copolymerization with ε-caprolactone (CL to poly(CL-co-OEG-MPO copolymers is presented. The statistical copolymerization initiated with SnOct2/BnOH yielded the copolymers with varying OEG content and composition. The linear relationship between feed ratio and incorporation of the OEG co-monomer enables control over backbone functional group density. The introduction of OEG moieties influenced both the thermal and the hydrophilic characteristics of the copolymers. Both increasing OEG length and backbone content resulted in a decrease in static water contact angle. The introduction of OEG side chains in the PCL copolymers had no adverse influence on MC-3TE3-E1 cell interaction. However, changes to cell form factor (Φ were observed. While unmodified PCL promoted elongated (anisotropic morphologies (Φ = 0.094, PCL copolymer with tri-ethylene glycol side chains at or above seven percent backbone incorporation induced more isotropic cell morphologies (Φ = 0.184 similar to those observed on glass controls (Φ = 0.151.

  20. The ecotoxicity of zinc and zinc-containing substances in soil with consideration of metal-moiety approaches and organometal complexes.

    Science.gov (United States)

    Ritchie, Ellyn; Boyd, Patrick; Lawson-Halasz, Annamaria; Hawari, Jalal; Saucier, Stacey; Scroggins, Richard; Princz, Juliska

    2017-12-01

    Within Canada, screening-level assessments for chemical substances are required to determine whether the substances pose a risk to human health and/or the environment, and as appropriate, risk management strategies. In response to the volume of metal and metal-containing substances, process efficiencies were introduced using a metal-moiety approach, whereby substances that contain a common metal moiety are assessed simultaneously as a group, with the moiety of concern consisting of the metal ion. However, for certain subgroups, such as organometals or organic metal salts, the organic moiety or parent substance may be of concern, rather than simply the metal ion. To further investigate the need for such additional consideration, certain substances were evaluated: zinc (Zn)-containing inorganic (Zn chloride [ZnCl2] and Zn oxide) and organic (organometal: Zn diethyldithiocarbamate [Zn(DDC) 2 ] and organic metal salts (Zn stearate [ZnSt] and 4-chloro-2-nitrobenzenediazonium tetrachlorozincate [BCNZ]). The toxicity of the substances were assessed using plant (Trifolium pratense and Elymus lanceolatus) and soil invertebrate (Folsomia candida and Eisenia andrei) tests in a sandy soil. Effect measures were determined based on total metal and total parent analyses (for organic substances). In general, the inorganic Zn substances were less toxic than the organometals and organic metal salts, with 50% effective concentrations ranging from 11 to >5194 mg Zn kg -1 dry soil. The data demonstrate the necessity for alternate approaches in the assessment of organo-metal complexes, with the organic moieties or parent substances warranting consideration rather than the metal ion alone. In this instance, the organometals and organic metal salts were significantly more toxic than other test substances despite their low total Zn content. Environ Toxicol Chem 2017;36:3324-3332. © 2017 Crown in the Right of Canada. Published by Wiley Periodicals Inc. on behalf of SETAC. © 2017 Crown

  1. Biosynthesis of triacylglycerols containing very long chain monounsaturated acyl moieties in developing seeds

    International Nuclear Information System (INIS)

    Fehling, E.; Murphy, D.J.; Mukherjee, K.D.

    1990-01-01

    Particulate (15,000g) fractions from developing seeds of honesty (Lunaria annua L.) and mustard (Sinapis alba L.) synthesize radioactive very long chain monounsaturated fatty acids (gadoleic, erucic, and nervonic) from [1- 14 C]oleoyl-CoA and malonyl-CoA or from oleoyl-CoA and [2- 14 C]malonyl-CoA. The very long chain monounsaturated fatty acids are rapidly channeled to triacylglycerols and other acyl lipids without intermediate accumulation of their CoA thioesters. When [1- 14 C]oleoyl-CoA is used as the radioactive substrate, phosphatidylcholines and other phospholipids are most extensively radiolabeled by oleoyl moieties rather than by very long chain monounsaturated acyl moieties. When [2- 14 C]malonyl-CoA is used as the radioactive substrate, no radioactive oleic acid is formed and the newly synthesized very long chain monounsaturated fatty acids are extensively incorporated into phosphatidylcholines and other phospholipids as well as triacylglycerols. The pattern of labeling of the key intermediates of the Kennedy pathway, e.g. lysophosphatidic acids, phosphatidic acids, and diacylglycerols by the newly synthesized very long chain monounsaturated fatty acids is consistent with the operation of this pathway in the biosynthesis of triacylglycerols

  2. New pentose dimers with bicyclic moieties from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, H.; Sørensen, Henrik Rokkjær; Tanner, David Ackland

    2017-01-01

    In lignocellulosic biorefinery processes involving enzyme catalysed reactions it is a challenge that enzyme inhibiting compounds are generated and liberated during pretreatment of the biomass. In this study the contribution to cellulase inhibition from xylooligosaccharides and newly discovered...... oligophenolic compounds from pilot scale pretreated wheat straw was assessed at two different pretreatment severities. An increase in severity of the pretreatment led to more oligophenol compounds and in turn the total overall cellulase inhibition increased. When the xylooligosaccharides were enzymatically...... degraded prior to cellulose hydrolysis, a relief in cellulase inhibition was observed, but some inhibition remained, suggesting that other components also played a role in inhibition. We propose that these components include dipentoses with bicyclic moieties and feruloylated tripentoses, because LC...

  3. Porous Lactose-Modified Chitosan Scaffold for Liver Tissue Engineering: Influence of Galactose Moieties on Cell Attachment and Mechanical Stability

    Directory of Open Access Journals (Sweden)

    Birong Wang

    2016-01-01

    Full Text Available Galactosylated chitosan (CTS has been widely applied in liver tissue engineering as scaffold. However, the influence of degree of substitution (DS of galactose moieties on cell attachment and mechanical stability is not clear. In this study, we synthesized the lactose-modified chitosan (Lact-CTS with various DS of galactose moieties by Schiff base reaction and reducing action of NaBH4, characterized by FTIR. The DS of Lact-CTS-1, Lact-CTS-2, and Lact-CTS-3 was 19.66%, 48.62%, and 66.21% through the method of potentiometric titration. The cell attachment of hepatocytes on the CTS and Lact-CTS films was enhanced accompanied with the increase of galactose moieties on CTS chain because of the galactose ligand-receptor recognition; however, the mechanical stability of Lact-CTS-3 was reduced contributing to the extravagant hydrophilicity, which was proved using the sessile drop method. Then, the three-dimensional Lact-CTS scaffolds were fabricated by freezing-drying technique. The SEM images revealed the homogeneous pore bearing the favorable connectivity and the pore sizes of scaffolds with majority of 100 μm; however, the extract solution of Lact-CTS-3 scaffold significantly damaged red blood cells by hemolysis assay, indicating that exorbitant DS of Lact-CTS-3 decreased the mechanical stability and increased the toxicity. To sum up, the Lact-CTS-2 with 48.62% of galactose moieties could facilitate the cell attachment and possess great biocompatibility and mechanical stability, indicating that Lact-CTS-2 was a promising material for liver tissue engineering.

  4. Scopranones with Two Atypical Scooplike Moieties Produced by Streptomyces sp. BYK-11038.

    Science.gov (United States)

    Uchida, Ryuji; Lee, Daiki; Suwa, Ibuki; Ohtawa, Masaki; Watanabe, Nozomu; Demachi, Ayumu; Ohte, Satoshi; Katagiri, Takenobu; Nagamitsu, Tohru; Tomoda, Hiroshi

    2017-11-03

    Three new compounds, designated scopranones A-C, were isolated from the culture broth of a soil isolate, Streptomyces sp. BYK-11038, and shown to be inhibitors of bone morphogenetic protein (BMP) induced alkaline phosphatase activity in a BMP receptor mutant cell line. The structures were elucidated using NMR and other spectral data. The scopranones have an unusual structure with two atypical scooplike moieties linked at the tails to form part of a unique 3-furanone ring.

  5. The nature of the Iron Moiety bisorped by immobilized Saccharomyces Cervisiae at low pH: A Mossbauer spectroscopic investigation

    International Nuclear Information System (INIS)

    Khalil, Mustaim I.; Al-Wassil, Abdulaziz I.

    1999-01-01

    The nature of the adsorped Fe-moiety on immobilized Saccharomyces Cervisiae at low pH has been investigated by Mossbauer spectroscopy. The Mossbauer spectrum at 77K exhibited two sites: the major one (69%) was a quadrupole-split double, Delta Q=0.77 mms with an isomer shift 0.46 mms, assigned to the high spin octahedrally coordinated iron (III); and a single line minor site (31%) with an isomer shift, d=0.36 mms, assigned to the high-spin tetrahedral iron (III) Cl-moiety. An electrostatic and a covalent mode of Fe binding were then inferred. (author)

  6. Diamond surface functionalization with biomimicry – Amine surface tether and thiol moiety for electrochemical sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sund, James B., E-mail: jim@jamessund.com [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Causey, Corey P. [Departments of Chemistry and Biochemistry, Duke University, Durham, NC (United States); Wolter, Scott D. [Department of Physics, Elon University, Elon, NC 27244 (United States); Parker, Charles B., E-mail: charles.parker@duke.edu [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Stoner, Brian R. [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States); Research Triangle Institute (RTI) International, Research Triangle Park, NC (United States); Toone, Eric J. [Departments of Chemistry and Biochemistry, Duke University, Durham, NC (United States); Glass, Jeffrey T. [Department of Electrical and Computer Engineering, Duke University, Durham, NC (United States)

    2014-05-01

    Highlights: • Diamond surfaces were functionalized with organic molecules using a novel approach. • Used biomimicry to select a molecule to bind NO, similar to the human body. • Molecular orbital theory predicted the molecule-analyte oxidation behavior. • A thiol moiety was attached to an amine surface tether on the diamond surface. • XPS analysis verified each surface functionalization step. - Abstract: The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen–oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis.

  7. Diamond surface functionalization with biomimicry – Amine surface tether and thiol moiety for electrochemical sensors

    International Nuclear Information System (INIS)

    Sund, James B.; Causey, Corey P.; Wolter, Scott D.; Parker, Charles B.; Stoner, Brian R.; Toone, Eric J.; Glass, Jeffrey T.

    2014-01-01

    Highlights: • Diamond surfaces were functionalized with organic molecules using a novel approach. • Used biomimicry to select a molecule to bind NO, similar to the human body. • Molecular orbital theory predicted the molecule-analyte oxidation behavior. • A thiol moiety was attached to an amine surface tether on the diamond surface. • XPS analysis verified each surface functionalization step. - Abstract: The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen–oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis

  8. Peptidyl prolyl isomerase Pin1-inhibitory activity of D-glutamic and D-aspartic acid derivatives bearing a cyclic aliphatic amine moiety.

    Science.gov (United States)

    Nakagawa, Hidehiko; Seike, Suguru; Sugimoto, Masatoshi; Ieda, Naoya; Kawaguchi, Mitsuyasu; Suzuki, Takayoshi; Miyata, Naoki

    2015-12-01

    Pin1 is a peptidyl prolyl isomerase that specifically catalyzes cis-trans isomerization of phosphorylated Thr/Ser-Pro peptide bonds in substrate proteins and peptides. Pin1 is involved in many important cellular processes, including cancer progression, so it is a potential target of cancer therapy. We designed and synthesized a novel series of Pin1 inhibitors based on a glutamic acid or aspartic acid scaffold bearing an aromatic moiety to provide a hydrophobic surface and a cyclic aliphatic amine moiety with affinity for the proline-binding site of Pin1. Glutamic acid derivatives bearing cycloalkylamino and phenylthiazole groups showed potent Pin1-inhibitory activity comparable with that of known inhibitor VER-1. The results indicate that steric interaction of the cyclic alkyl amine moiety with binding site residues plays a key role in enhancing Pin1-inhibitory activity. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Poly(2-vinyl pyridine)-block-poly(ethylene oxide) featuring a furan group at the block junction-synthesis and functionalization.

    Science.gov (United States)

    Rudolph, Tobias; Barthel, Markus J; Kretschmer, Florian; Mansfeld, Ulrich; Hoeppener, Stephanie; Hager, Martin D; Schubert, Ulrich S; Schacher, Felix H

    2014-05-01

    Furfuryl glycidyl ether (FGE) represents a highly versatile monomer for the preparation of reversibly cross-linkable nanostructured materials via Diels-Alder reactions. Here, the use of FGE for the mid-chain functionalization of a P2VP-b-PEO diblock copolymer is reported. The material features one furan moiety at the block junction, P2VP68 -FGE-b-PEO390 , which can be subsequently addressed in Diels-Alder reactions using maleimide-functionalized counterparts. The presence of the FGE moiety enables the introduction of dyes as model labels or the formation of hetero-grafted brushes as shell on hybrid Au@Polymer nanoparticles. This renders P2VP68 -FGE-b-PEO390 , a powerful tool for selective functionalization reactions, including the modification of surfaces. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Accumulation of medium-chain, saturated fatty acyl moieties in seed oils of transgenic Camelina sativa.

    Directory of Open Access Journals (Sweden)

    Zhaohui Hu

    Full Text Available With its high seed oil content, the mustard family plant Camelina sativa has gained attention as a potential biofuel source. As a bioenergy crop, camelina has many advantages. It grows on marginal land with low demand for water and fertilizer, has a relatively short life cycle, and is stress tolerant. As most other crop seed oils, camelina seed triacylglycerols (TAGs consist of mostly long, unsaturated fatty acyl moieties, which is not desirable for biofuel processing. In our efforts to produce shorter, saturated chain fatty acyl moieties in camelina seed oil for conversion to jet fuel, a 12:0-acyl-carrier thioesterase gene, UcFATB1, from California bay (Umbellularia californica Nutt. was expressed in camelina seeds. Up to 40% of short chain laurate (C12:0 and myristate (C14:0 were present in TAGs of the seed oil of the transgenics. The total oil content and germination rate of the transgenic seeds were not affected. Analysis of positions of these two fatty acyl moieties in TAGs indicated that they were present at the sn-1 and sn-3 positions, but not sn-2, on the TAGs. Suppression of the camelina KASII genes by RNAi constructs led to higher accumulation of palmitate (C16:0, from 7.5% up to 28.5%, and further reduction of longer, unsaturated fatty acids in seed TAGs. Co-transformation of camelina with both constructs resulted in enhanced accumulation of all three medium-chain, saturated fatty acids in camelina seed oils. Our results show that a California bay gene can be successfully used to modify the oil composition in camelina seed and present a new biological alternative for jet fuel production.

  11. TRPA1-dependent reversible opening of tight junction by natural compounds with an α,β-unsaturated moiety and capsaicin.

    Science.gov (United States)

    Kanda, Yusuke; Yamasaki, Youhei; Sasaki-Yamaguchi, Yoshie; Ida-Koga, Noriko; Kamisuki, Shinji; Sugawara, Fumio; Nagumo, Yoko; Usui, Takeo

    2018-02-02

    The delivery of hydrophilic macromolecules runs into difficulties such as penetration of the cell membrane lipid bilayer. Our prior experiment demonstrated that capsaicin induces the reversible opening of tight junctions (TJs) and enhances the delivery of hydrophilic macromolecules through a paracellular route. Herein, we screened paracellular permeability enhancers other than capsaicin. As TJ opening by capsaicin is associated with Ca 2+ influx, we first screened the compounds that induce Ca 2+ influx in layered MDCK II cells, and then we determined the compounds' abilities to open TJs. Our results identified several natural compounds with α,β-unsaturated moiety. A structure-activity relationship (SAR) analysis and the results of pretreatment with reducing reagent DTT suggested the importance of α,β-unsaturated moiety. We also examined the underlying mechanisms, and our findings suggest that the actin reorganization seen in capsaicin treatment is important for the reversibility of TJ opening. Furthermore, our analyses revealed that TRPA1 is involved in the Ca 2+ influx and TJ permeability increase not only by an α,β-unsaturated compound but also by capsaicin. Our results indicate that the α,β-unsaturated moiety can be a potent pharmacophore for TJ opening.

  12. Structural elucidation of the polysaccharide moiety of a glycopeptide (GLPCW-II) from Ganoderma lucidum fruiting bodies.

    Science.gov (United States)

    Ye, LiBin; Zhang, JingSong; Ye, XiJun; Tang, QingJiu; Liu, YanFang; Gong, ChunYu; Du, XiuJui; Pan, YingJie

    2008-03-17

    A water-soluble glycopeptide (GLPCW-II) was isolated from the fruiting bodies of Ganoderma lucidum by DEAE-Sepharose Fast-Flow and Sephacryl S-300 High Resolution Chromatography. The glycopeptide had a molecular weight of 1.2x10(4)Da (determined by HPLC), and consisted of approximately 90% carbohydrate and approximately 8% protein as determined using the phenol-sulfuric acid method and the BCA protein assay reagent kit, respectively. The polysaccharide moiety was composed mainly of D-Glc, L-Fuc, and D-Gal in the ratio of 1.00:1.09:4.09. To facilitate structure-activity studies, the structure of the GLPCW-II polysaccharide moiety was elucidated using 1H and 13C NMR spectroscopy including COSY, TOCSY, HMBC, HSQC, and ROESY, combined with GC-MS of methylated derivatives, and shown to consist of repeating units with the following structure: [Formula: see text].

  13. Effect of a spacer moiety on radiometal labelled Neurotensin derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, A.; Valverde, I.E.; Mindt, T.L. [Univ. of Basel Hospital (Switzerland). Div. of Radiopharmaceutical Chemistry

    2013-07-01

    The binding sequence of the regulatory peptide Neurotensin, NT(8-13), represents a promising tumour-specific vector for the development of radiopeptides useful in nuclear oncology for the diagnosis (imaging) and therapy of cancer. A number of radiometal-labelled NT(8-13) derivatives have been reported, however, the effect of the spacer which connects the vector with the radiometal complex has yet not been investigated systematically. Because a spacer moiety can influence potentially important biological characteristics of radiopeptides, we synthesized three [DOTA({sup 177}Lu)]-X-NT(8-13) derivatives and evaluated the effect of a spacer (X) on the physico-chemical properties of the conjugate including lipophilicity, stability, and in vitro receptor affinity and cell internalization. (orig.)

  14. A survey of cyclic replacements for the central diamide moiety of inhibitors of inosine monophosphate dehydrogenase.

    Science.gov (United States)

    Dhar, T G Murali; Liu, Chunjian; Pitts, William J; Guo, Junquing; Watterson, Scott H; Gu, Henry; Fleener, Catherine A; Rouleau, Katherine; Sherbina, N Z; Barrish, Joel C; Hollenbaugh, Diane; Iwanowicz, Edwin J

    2002-11-04

    A series of heterocyclic replacements for the central diamide moiety of 1, a potent small molecule inhibitor of inosine monophosphate dehydrogenase (IMPDH) were explored The synthesis and the structure-activity relationships (SARs), derived from in vitro studies, for these new series of inhibitors is given.

  15. Surface modified liposomes by mannosylated conjugates anchored via the adamantyl moiety in the lipid bilayer.

    Science.gov (United States)

    Stimac, Adela; Segota, Suzana; Dutour Sikirić, Maja; Ribić, Rosana; Frkanec, Leo; Svetličić, Vesna; Tomić, Srđanka; Vranešić, Branka; Frkanec, Ruža

    2012-09-01

    The aim of the present study was to encapsulate mannosylated 1-aminoadamantane and mannosylated adamantyltripeptides, namely [(2R)-N-(adamant-1-yl)-3-(α,β-d-mannopyranosyloxy)-2-methylpropanamide and (2R)-N-[3-(α-d-mannopyranosyloxy)-2-methylpropanoyl]-d,l-(adamant-2-yl)glycyl-l-alanyl-d-isoglutamine] in liposomes. The characterization of liposomes, size and surface morphology was performed using dynamic light scattering (DLS) and atomic force microscopy (AFM). The results have revealed that the encapsulation of examined compounds changes the size and surface of liposomes. After the concanavalin A (ConA) was added to the liposome preparation, increase in liposome size and their aggregation has been observed. The enlargement of liposomes was ascribed to the specific binding of the ConA to the mannose present on the surface of the prepared liposomes. Thus, it has been shown that the adamantyl moiety from mannosylated 1-aminoadamantane and mannosylated adamantyltripeptides can be used as an anchor in the lipid bilayer for carbohydrate moiety exposed on the liposome surface. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Engineered jadomycin analogues with altered sugar moieties revealing JadS as a substrate flexible O-glycosyltransferase.

    Science.gov (United States)

    Li, Liyuan; Pan, Guohui; Zhu, Xifen; Fan, Keqiang; Gao, Wubin; Ai, Guomin; Ren, Jinwei; Shi, Mingxin; Olano, Carlos; Salas, José A; Yang, Keqian

    2017-07-01

    Glycosyltransferases (GTs)-mediated glycodiversification studies have drawn significant attention recently, with the goal of generating bioactive compounds with improved pharmacological properties by diversifying the appended sugars. The key to achieving glycodiversification is to identify natural and/or engineered flexible GTs capable of acting upon a broad range of substrates. Here, we report the use of a combinatorial biosynthetic approach to probe the substrate flexibility of JadS, the GT in jadomycin biosynthesis, towards different non-native NDP-sugar substrates, enabling us to identify six jadomycin B analogues with different sugar moieties. Further structural engineering by precursor-directed biosynthesis allowed us to obtain 11 new jadomycin analogues. Our results for the first time show that JadS is a flexible O-GT that can utilize both L- and D- sugars as donor substrates, and tolerate structural changes at the C2, C4 and C6 positions of the sugar moiety. JadS may be further exploited to generate novel glycosylated jadomycin molecules in future glycodiversification studies.

  17. Synthesis and Herbicidal Activity of Novel Sulfonylureas Containing 1,2,4-Triazolinone Moiety

    Institute of Scientific and Technical Information of China (English)

    LIU Zhuo; PAN Li; LI Yong-hong; WANG Su-hua; LI Zheng-ming

    2013-01-01

    A series of new sulfonylureas incorporating 1,2,4-triazolinone moiety was synthesized,which were further bio-assayed for the herbicidal activity against four herbs,representative of monocotyledons and dicotyledons.Some of them exhibited high potency to inhibit the growth of dicotyledons(Bassica napus and Amaranthus retroflexus) in the pot experiment.Compounds 9a and 9b also displayed an excellent herbicidal activity against Bassica napus at a concentration of 15 g/hectare,which were comparable with commercial triasulfuron.

  18. Radiolysis of aqueous solutions of nucleosides halogenated at the sugar moiety

    Energy Technology Data Exchange (ETDEWEB)

    Hissung, A; Isildar, M; von Sonntag, C [Max-Planck-Institut fuer Kohlenforschung, Muelheim an der Ruhr (Germany, F.R.). Inst. fuer Strahlenforschung; Witzel, H [Biochemisches Institut der Westfaelischen Wilhelms-Universitaet, Muenster, West Germany

    1981-02-01

    The pulse radiolysis of aqueous solutions of nucleosides halogenated at the sugar moiety (2'-bromo-2'-deoxyuridine 4, 3'-deoxy-3'-iodothymidine 5, 5'-deoxy-5'-iodouridine 6) has been studied. G(Hal) were determined by conductometry varying the experimental conditions (pH, saturation with Ar, N/sub 2/O or air, addition of t-butanol). The results indicate that solvated electrons both add to the nucleobases and eliminate halogen ions from the halogenated sugar moiety. In the case of 4(and possibly of 5) the radical anion of the base transfers (k approximately 10/sup 5/s/sup -1/) an electron to the sugar-bound halogen atom thus cleaving the C-Hal bond. In competition with this reaction there is a protonation of the radical anion of the base by protons and by water. For the latter reaction constant of k = 5 x 10/sup 3/ M/sup -1/s/sup -1/ was estimated. Compound 4 has also been investigated by product analysis after 60-Co-..gamma..-irradiation. In aerated solutions erythrose is formed with a G-value of 0.12. Its precursor radical is the 2'-radical generated from 4 by dissociative electron capture which reacts with O/sub 2/ to the corresponding peroxyl radical. Erythrose is formed after a sequence of reactions, one of which involves the scission of the C-1'-C-2'bond. Under this condition G(HBr) as measured by pulse radiolysis is 0.8. Thus erythrose is formed in 15 per cent yield with respect to its precursor radical. This result is of importance in assessing the precursor radical of a similar product observed in irradiated DNA.

  19. Radiolysis of aqueous solutions of nucleosides halogenated at the sugar moiety

    International Nuclear Information System (INIS)

    Hissung, A.; Isildar, M.; Sonntag, C. von; Witzel, H.

    1981-01-01

    The pulse radiolysis of aqueous solutions of nucleosides halogenated at the sugar moiety (2'-bromo-2'-deoxyuridine 4, 3'-deoxy-3'-iodothymidine 5, 5'-deoxy-5'-iodouridine 6) has been studied. G(Hal) were determined by conductometry varying the experimental conditions (pH, saturation with Ar, N 2 O or air, addition of t-butanol). The results indicate that solvated electrons both add to the nucleobases and eliminate halogen ions from the halogenated sugar moiety. In the case of 4(and possibly of 5) the radical anion of the base transfers (k approximately 10 5 s -1 ) an electron to the sugar-bound halogen atom thus cleaving the C-Hal bond. In competition with this reaction there is a protonation of the radical anion of the base by protons and by water. For the latter reaction constant of k = 5 x 10 3 M -1 s -1 was estimated. Compound 4 has also been investigated by product analysis after 60-Co-γ-irradiation. In aerated solutions erythrose is formed with a G-value of 0.12. Its precursor radical is the 2'-radical generated from 4 by dissociative electron capture which reacts with O 2 to the corresponding peroxyl radical. Erythrose is formed after a sequence of reactions, one of which involves the scission of the C-1'-C-2'bond. Under this condition G(HBr) as measured by pulse radiolysis is 0.8. Thus erythrose is formed in 15 per cent yield with respect to its precursor radical. This result is of importance in assessing the precursor radical of a similar product observed in irradiated DNA. (author)

  20. Inhibitors of inosine monophosphate dehydrogenase: SARs about the N-[3-Methoxy-4-(5-oxazolyl)phenyl moiety.

    Science.gov (United States)

    Iwanowicz, Edwin J; Watterson, Scott H; Guo, Junqing; Pitts, William J; Murali Dhar, T G; Shen, Zhongqi; Chen, Ping; Gu, Henry H; Fleener, Catherine A; Rouleau, Katherine A; Cheney, Daniel L; Townsend, Robert M; Hollenbaugh, Diane L

    2003-06-16

    The first reported structure-activity relationships (SARs) about the N-[3-methoxy-4-(5-oxazolyl)phenyl moiety for a series of recently disclosed inosine monophosphate dehydrogenase (IMPDH) inhibitors are described. The syntheses and in vitro inhibitory values for IMPDH II, and T-cell proliferation (for select analogues) are given.

  1. Discovery and biological evaluation of some (1H-1,2,3-triazol-4-yl)methoxybenzaldehyde derivatives containing an anthraquinone moiety as potent xanthine oxidase inhibitors.

    Science.gov (United States)

    Zhang, Ting-Jian; Li, Song-Ye; Yuan, Wei-Yan; Wu, Qing-Xia; Wang, Lin; Yang, Su; Sun, Qi; Meng, Fan-Hao

    2017-02-15

    A series of (1H-1,2,3-triazol-4-yl)methoxybenzaldehyde derivatives containing an anthraquinone moiety were synthesized and identified as novel xanthine oxidase inhibitors. Among them, the most promising compounds 1h and 1k were obtained with IC 50 values of 0.6μM and 0.8μM, respectively, which were more than 10-fold potent compared with allopurinol. The Lineweaver-Burk plot revealed that compound 1h acted as a mixed-type xanthine oxidase inhibitor. SAR analysis showed that the benzaldehyde moiety played a more important role than the anthraquinone moiety for inhibition potency. The basis of significant inhibition of xanthine oxidase by 1h was rationalized by molecular modeling studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Chemical Synthesis and Biological Activities of Novel Pleuromutilin Derivatives with Substituted Amino Moiety

    Science.gov (United States)

    Shang, Ruofeng; Wang, Shengyu; Xu, Ximing; Yi, Yunpeng; Guo, Wenzhu; YuLiu; Liang, Jianping

    2013-01-01

    Novel pleuromutilin derivatives designed based on the structure of valnemulin were synthesized and evaluated for their in vitro antibacterial activities. These pleuromutilin derivatives with substituted amino moiety exhibited excellent activities against methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, Escherichia coli, and Streptococcus agalactiae. Compound 5b showed the highest antibacterial activities and even exceeded tiamulin. Moreover, the docking experiments provided information about the binding model between the synthesized compounds and peptidyl transferase center (PTC) of 23S rRNA. PMID:24376551

  3. Chemical synthesis and biological activities of novel pleuromutilin derivatives with substituted amino moiety.

    Directory of Open Access Journals (Sweden)

    Ruofeng Shang

    Full Text Available Novel pleuromutilin derivatives designed based on the structure of valnemulin were synthesized and evaluated for their in vitro antibacterial activities. These pleuromutilin derivatives with substituted amino moiety exhibited excellent activities against methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, Escherichia coli, and Streptococcus agalactiae. Compound 5b showed the highest antibacterial activities and even exceeded tiamulin. Moreover, the docking experiments provided information about the binding model between the synthesized compounds and peptidyl transferase center (PTC of 23S rRNA.

  4. Synthesis of Morpholine Containing Sulfonamides: Introduction of Morpholine Moiety on Amine Functional Group

    Directory of Open Access Journals (Sweden)

    D. Singh

    2004-01-01

    Full Text Available Sulfonamides have been the center of drug structures as this group is quite stable & well tolerated in human beings. The synthesis of these structures was started in search of new pharmacological active reagents. These compounds are being tested for the desired activity (ICAM-1/LFA-1 Interaction inhibitors as anti-adhesion therapeutic agents, the biological activity & structure activity relationship will be published elsewhere. Synthesis of morpholine moiety from amino group is done by using reagent 2-chloroethanol.

  5. Structural features facilitating tumor cell targeting and internalization by bleomycin and its disaccharide.

    Science.gov (United States)

    Yu, Zhiqiang; Paul, Rakesh; Bhattacharya, Chandrabali; Bozeman, Trevor C; Rishel, Michael J; Hecht, Sidney M

    2015-05-19

    We have shown previously that the bleomycin (BLM) carbohydrate moiety can recapitulate the tumor cell targeting effects of the entire BLM molecule, that BLM itself is modular in nature consisting of a DNA-cleaving aglycone which is delivered selectively to the interior of tumor cells by its carbohydrate moiety, and that there are disaccharides structurally related to the BLM disaccharide which are more efficient than the natural disaccharide at tumor cell targeting/uptake. Because BLM sugars can deliver molecular cargoes selectively to tumor cells, and thus potentially form the basis for a novel antitumor strategy, it seemed important to consider additional structural features capable of affecting the efficiency of tumor cell recognition and delivery. These included the effects of sugar polyvalency and net charge (at physiological pH) on tumor cell recognition, internalization, and trafficking. Since these parameters have been shown to affect cell surface recognition, internalization, and distribution in other contexts, this study has sought to define the effects of these structural features on tumor cell recognition by bleomycin and its disaccharide. We demonstrate that both can have a significant effect on tumor cell binding/internalization, and present data which suggests that the metal ions normally bound by bleomycin following clinical administration may significantly contribute to the efficiency of tumor cell uptake, in addition to their characterized function in DNA cleavage. A BLM disaccharide-Cy5** conjugate incorporating the positively charged dipeptide d-Lys-d-Lys was found to associate with both the mitochondria and the nuclear envelope of DU145 cells, suggesting possible cellular targets for BLM disaccharide-cytotoxin conjugates.

  6. Functionalized mesoporous silicas with crown ether moieties for selective adsorption of lithium ions in artificial sea water.

    Science.gov (United States)

    Sung, Soo Park; Moorthy, Madhappan Santha; Song, Hyun-Jin; Ha, Chang-Sik

    2014-11-01

    Lithium ion has been increasingly recognized in a wide range of industrial applications. In this work, we studied on the adsorption of Li+ in the artificial seawater with high selectivity using methyl-crown ether (AC-SBA-15) and aza-crown ether (HMC-SBA-15) moieties-functionalized mesoporous silica materials. First, methyl-crown ether and aza-crown ether moieties-functionalized mesoporous silica materials were synthesized via two-step post-synthesis process using a grafting method. The functionalized materials were employed to the metal ion adsorption from aqueous solution (artificial seawater) containing Li+, Co2+, Cr3+ and Hg2+. The prepared hybrid material showed high selectivity for Li+ ion in the artificial seawater at pH 8.0. The absorbed amount of Li+ was 73 times higher than Cr3+ for aza-crown ether containing AC-SBA-15 as an absorbent. The absorbed amount of Co2+ (4.5 x 10(-5) mol/g), Cr3+ (1.5 x 10(-5) mol/g) and Hg2+ (2.25 x 10(-4) mol/g) were remarkably lower than the case of Li+. On the other hand, the absorbed amount of various metal ions of HMC-SBA-15 with amine groups in alky chains and crown ether moieties were 1.1 x 10(-3) mol/g for Li+, 5.0 x 10(-5) mol/g for Co2+, 2.9 x 10(-4) mol/g for Cr3+, 2.8 x 10(-4) mol/g for Hg2+ mol/g, respectively.

  7. Synthesis of New Thiazole Derivatives Bearing A Sulfonamide Moiety Of Expected Anticancer And Radiosensitizing Activities

    International Nuclear Information System (INIS)

    Mohamed, S.Sh.I.

    2012-01-01

    In a search for new cytotoxic agents with improved antitumor activity and selectivity, some new pyrano thiazole and thiazolopyranopyrimidine derivatives bearing sulfonamide moiety were synthesized. The newly synthesized compounds were evaluated for their antitumor activity alone and in combination with γ-irradiation. These new compounds were docked inside the active site of carbonic anhydrase II to predict their mechanism of action.

  8. How Secondary and Tertiary Amide Moieties are Molecular Stations for Dibenzo-24-crown-8 in [2]Rotaxane Molecular Shuttles?

    Science.gov (United States)

    Riss-Yaw, Benjamin; Morin, Justine; Clavel, Caroline; Coutrot, Frédéric

    2017-11-21

    Interlocked molecular machines like [2]rotaxanes are intriguing aesthetic molecules. The control of the localization of the macrocycle, which surrounds a molecular axle, along the thread leads to translational isomers of very different properties. Although many moieties have been used as sites of interactions for crown ethers, the very straightforwardly obtained amide motif has more rarely been envisaged as molecular station. In this article, we report the use of secondary and tertiary amide moieties as efficient secondary molecular station in pH-sensitive molecular shuttles. Depending on the N -substitution of the amide station, and on deprotonation or deprotonation-carbamoylation, the actuation of the molecular machinery differs accordingly to very distinct interactions between the axle and the DB24C8.

  9. Antidepressant potential of nitrogen-containing heterocyclic moieties: An updated review

    Directory of Open Access Journals (Sweden)

    Nadeem Siddiqui

    2011-01-01

    Full Text Available Depression is currently the fourth leading cause of disease or disability worldwide. Antidepressant is approved for the treatment of major depression (including paediatric depression, obsessive-compulsive disorder (in both adult and paediatric populations, bulimia nervosa, panic disorder and premenstrual dysphoric disorder. Antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. Many drugs produce an antidepressant effect, but restrictions on their use have caused controversy and off-label prescription a risk, despite claims of superior efficacy. Our current understanding of its pathogenesis is limited and existing treatments are inadequate, providing relief to only a subset of people suffering from depression. Reviews of literature suggest that heterocyclic moieties and their derivatives has proven success in treating depression.

  10. Radiation chemistry of carbohydrates and of the sugar moiety in DNA

    International Nuclear Information System (INIS)

    Sonntag, C. von

    1979-01-01

    The free radical chemistry of carbohydrates as studied by radiation techniques is briefly reviewed. In aqueous solutions OH radicals and H atoms abstract carbon-bound H atoms to give the primary carbohydrate radicals which can undergo a number of elimination and rearrangement reactions leading to secondary carbohydrate radicals. Oxygen can suppress these elimination and rearrangement reactions by converting the primary carbohydrate radicals into the corresponding peroxyl radicals. The reactions leading to the observed products are discussed. In the solid state a few carbohydrates show radiation-induced chain reactions which are of preparative interest. Hydroxyl radical attack at the sugar moiety of DNA eventually leads to DNA strand breaks and to alkali-labile sites. (Auth.)

  11. Facile Synthesis of Novel Vanillin Derivatives Incorporating a Bis(2-hydroxyethyl)dithhioacetal Moiety as Antiviral Agents.

    Science.gov (United States)

    Zhang, Jian; Zhao, Lei; Zhu, Chun; Wu, Zengxue; Zhang, Guoping; Gan, Xiuhai; Liu, Dengyue; Pan, Jianke; Hu, Deyu; Song, Baoan

    2017-06-14

    A series of vanillin derivatives incorporating a bis(2-hydroxyethyl)dithioacetal moiety was designed and synthesized via a facile method. A plausible reaction pathway was proposed and verified by computational studies. Bioassay results demonstrated that target compounds possessed good to excellent activities against potato virus Y (PVY) and cucumber mosaic virus (CMV), of which, compound 6f incorporating a bis(2-hydroxyethyl)dithioacetal moiety, exhibited the best curative and protection activities against PVY and CMV in vivo, with 50% effective concentration values of 217.6, 205.7 μg/mL and 206.3, 186.2 μg/mL, respectively, better than those of ribavirin (848.0, 808.1 μg/mL and 858.2, 766.5 μg/mL, respectively), dufulin (462.6, 454.8 μg/mL and 471.2, 465.4 μg/mL, respectively), and ningnanmycin (440.5, 425.3 μg/mL and 426.1, 405.3 μg/mL, respectively). Current studies provide support for the application of vanillin derivatives incorporating bis(2-hydroxyethyl)dithioacetal as new antiviral agents.

  12. Reactive fillers based on SWCNTs functionalized with matrix-based moieties for the production of epoxy composites with superior and tunable properties

    International Nuclear Information System (INIS)

    González-Domínguez, Jose M; Ansón-Casaos, A; Martínez, M Teresa; Martínez-Rubí, Yadienka; Simard, Benoit; Díez-Pascual, Ana M; Gómez-Fatou, Marian

    2012-01-01

    Composite materials based on epoxy matrix and single-walled carbon nanotubes (SWCNTs) are able to exhibit outstanding improvements in physical properties when using a tailored covalent functionalization with matrix-based moieties containing terminal amines or epoxide rings. The proper choice of grafted moiety and integration protocol makes it feasible to tune the composite physical properties. At 0.5 wt% SWCNT loading, these composites exhibit up to 65% improvement in storage modulus, 91% improvement in tensile strength, and 65% improvement in toughness. A 15 °C increase in the glass transition temperature relative to the parent matrix was also achieved. This suggests that a highly improved interfacial bonding between matrix and filler, coupled to improved dispersion, are achieved. The degradation temperatures show an upshift in the range of 40–60 °C, which indicates superior thermal performance. Electrical conductivity ranges from ∼10 −13 to ∼10 −3 S cm −1 , which also shows the possibility of tuning the insulating or conductive behaviour of the composites. The chemical affinity of the functionalization moieties with the matrix and the unchanged molecular structure at the SWCNT/matrix interface are responsible for such improvements. (paper)

  13. Two-dimensional NMR spectroscopy links structural moieties of soil organic matter to the temperature sensitivity of its decomposition

    Science.gov (United States)

    Soucemarianadin, Laure; Erhagen, Björn; Öquist, Mats; Nilsson, Mats; Schleucher, Jürgen

    2015-04-01

    Soil organic matter (SOM) represents a huge carbon pool, specifically in boreal ecosystems. Warming-induced release of large amounts of CO2 from the soil carbon pool might become a significant exacerbating feedback to global warming, if decomposition rates of boreal soils were more sensitive to increased temperatures. Despite a large number of studies dedicated to the topic, it has proven difficult to elucidate how the organo-chemical composition of SOM influences its decomposition, or its quality as a substrate for microbial metabolism. A great part of this challenge results from our inability to achieve a detailed characterization of the complex composition of SOM on the level of molecular structural moieties. 13C nuclear magnetic resonance (NMR) spectroscopy is a common tool to characterize SOM. However, SOM is a very complex mixture and the chemical shift regions distinguished in the 13C NMR spectra often represent many different molecular fragments. For example, in the carbohydrates region, signals of all monosaccharides present in many different polymers overlap. This overlap thwarts attempts to identify molecular moieties, resulting in insufficient information to characterize SOM composition. We applied two-dimensional (2D) NMR to characterize SOM with highly increased resolution. We directly dissolved finely ground litters and forest floors'fibric and humic horizons'of both coniferous and deciduous boreal forests in dimethyl sulfoxide and analyzed the resulting solution with a 2D 1H-13C NMR experiment. In the 2D planes of these spectra, signals of CH groups can be resolved based on their 13C and 1H chemical shifts, hence the resolving power and information content of these NMR spectra is hugely increased. The 2D spectra indeed resolved overlaps observed in 1D 13C spectra, so that hundreds of distinct CH groups could be observed and many molecular fragments could be identified. For instance, in the aromatics region, signals from individual lignin units could

  14. Synthesis and antimicrobial properties of 1,3,4-oxadiazole analogs containing dibenzosuberone moiety

    Energy Technology Data Exchange (ETDEWEB)

    Moger, Manjunath [Mangalore University, Karnataka (India). Department of Chemistry; Satam, Vijay; Paniraj, A.S.; Gopinath, Vadiraj S.; Hindupur, Rama Mohan; Pati, Hari N., E-mail: hari.pati@advinus.com [Advinus Therapeutics Ltd., 21 and 22, Phase II, Peenya Industrial Area, Karnataka (India); Govindaraju, Darshan Raj C. [Department of Bio-Medicinal Research, Vidya Herbs Pvt. Ltd., Karnataka (India)

    2014-01-15

    A series of ten novel 1,3,4-oxadiazole analogs containing dibenzosuberone moiety were synthesized using linear as well as convergent synthesis approach. All the compounds were characterized by mass spectrometry, infrared (IR), {sup 1}H and {sup 13}C nuclear magnetic resonance ({sup 1}H NMR and {sup 13}C NMR) spectroscopies and elemental analysis. These compounds were evaluated for antibacterial and antifungal activities. Among ten analogs, four compounds, namely, 8a, 8d, 8e and 8j were found to be highly active antibacterial and antifungal agents (author)

  15. Synthesis of Some New 1,3,4-Thiadiazole, Thiazole and Pyridine Derivatives Containing 1,2,3-Triazole Moiety

    Directory of Open Access Journals (Sweden)

    Nadia A. Abdelriheem

    2017-02-01

    Full Text Available In this study, 1-(5-Methyl-1-(p-tolyl-1H-1,2,3-triazol-4-ylethan-1-one, was reacted with Thiosemicarbazide, alkyl carbodithioate and benzaldehyde to give thiosemicarbazone, alkylidenehydrazinecarbodithioate and 3-phenylprop-2-en-1-one-1,2,3-triazole derivatives. The 1,3,4-thiadiazole derivatives containing the 1,2,3-triazole moiety were obtained via reaction of alkylidenecarbodithioate with hydrazonoyl halides. Also, hydrazonoyl halides were reacted with thiosemicarbazone and pyrazolylthioamide to give 1,3-thiazoles derivatives. Subsequently, 3-phenyl2-en-1-one was used to synthesize substituted pyridines and substituted nicotinic acid ester. The latter was converted to its azide compound which was reacted with aromatic amines and phenol to give substituted urea and phenylcarbamate containing 1,2,3-triazole moiety. The newly synthesized compounds were established by elemental analysis, spectral data and alternative synthesis whenever possible.

  16. Synthesis and Antibacterial Evaluation of Novel Heterocyclic Compounds Containing a Sulfonamido Moiety

    Directory of Open Access Journals (Sweden)

    Eman A. El-Bordany

    2013-01-01

    Full Text Available Aiming for the synthesis of new heterocyclic compounds containing a sulfonamido moiety suitable for use as antibacterial agents, the precursor ethyl {[4-N-(4,6-dimethylpyrimidin-2-ylsulfamoyl]phenylazo}cyanoacetate was reacted with a variety of active methylene compounds producing pyran, pyridine and pyridazine derivatives. Also, the reactivity of the precursor hydrazone towards hydrazine derivatives to give pyrazole and oxazole derivatives was studied. On the other hand, treatment of the same precursor with urea, thiourea and/or guanidine hydrochloride furnished pyrimidine and thiazine derivatives, respectively. The newly synthesized compounds were tested for antibacterial activity, whereby eight compounds were found to have high activities.

  17. Attachment of inorganic moieties onto aliphatic polyurethanes

    Directory of Open Access Journals (Sweden)

    Eliane Ayres

    2007-06-01

    Full Text Available Polyurethanes have been used in a series of applications due basically to their versatility in terms of controlling the behavior by altering basically the type of reagents used. However, for more specific and advanced applications, such as in membranes, biomaterials and sensors, well-organized and defined chemical functionalities are necessary. In this work, inorganic functionalities were incorporated into aliphatic polyurethanes (PU having different macromolecular architectures. Polyurethanes were synthesized using a polyether diol and dicyclohexylmethane 4,4' diisocyanate (H12-MDI. Polyurethanes having carboxylic acid groups were also produced by introducing 2,2- bis (hydroxymethyl propionic acid in the polymerization process. Inorganic functionalities were inserted into polyurethanes by reacting isocyanate end capped chains with aminopropyltriethoxysilane followed by tetraethoxysilane. PU having carboxylic acid groups yielded transparent samples after the incorporation of inorganic entities, as an evidence of smaller and better dispersed inorganic entities in the polymer network. FTIR and swelling measurements showed that polyurethanes having carboxylic acid groups had inorganic domains less packed, condensed and cross-linked when compared to polyurethanes with no carboxylic acid groups. Results also suggested that the progressive incorporation of inorganic moieties in both types of polyurethanes occurred in regions previously activated with inorganic functionalities, instead of by the creation of new domains. The temperatures of thermal decomposition and glass transition were also shifted to higher temperatures when inorganic functionalities were incorporated into polyurethanes.

  18. Structural Features Facilitating Tumor Cell Targeting and Internalization by Bleomycin and Its Disaccharide

    Science.gov (United States)

    2016-01-01

    We have shown previously that the bleomycin (BLM) carbohydrate moiety can recapitulate the tumor cell targeting effects of the entire BLM molecule, that BLM itself is modular in nature consisting of a DNA-cleaving aglycone which is delivered selectively to the interior of tumor cells by its carbohydrate moiety, and that there are disaccharides structurally related to the BLM disaccharide which are more efficient than the natural disaccharide at tumor cell targeting/uptake. Because BLM sugars can deliver molecular cargoes selectively to tumor cells, and thus potentially form the basis for a novel antitumor strategy, it seemed important to consider additional structural features capable of affecting the efficiency of tumor cell recognition and delivery. These included the effects of sugar polyvalency and net charge (at physiological pH) on tumor cell recognition, internalization, and trafficking. Since these parameters have been shown to affect cell surface recognition, internalization, and distribution in other contexts, this study has sought to define the effects of these structural features on tumor cell recognition by bleomycin and its disaccharide. We demonstrate that both can have a significant effect on tumor cell binding/internalization, and present data which suggests that the metal ions normally bound by bleomycin following clinical administration may significantly contribute to the efficiency of tumor cell uptake, in addition to their characterized function in DNA cleavage. A BLM disaccharide-Cy5** conjugate incorporating the positively charged dipeptide d-Lys-d-Lys was found to associate with both the mitochondria and the nuclear envelope of DU145 cells, suggesting possible cellular targets for BLM disaccharide–cytotoxin conjugates. PMID:25905565

  19. Synthesis, reactions, and antiarrhythmic activities of some novel pyrimidines and pyridines fused with thiophene moiety

    OpenAIRE

    AMR, Abdel-Galil El-Sayed; ABDEL-HAFEZ, Naglaa Abdel-Samei

    2009-01-01

    We report herein the synthesis and antiarrhythmic activities of some newly synthesized heterocyclic theino[2,3-c]pyrimidine and theino[2,3-c]pyridine derivatives fused with thiophene moiety. Initially the acute toxicity of the compounds was assayed via the determination of their LD50. The antiarrhythmic activities for the compounds were determined and all the tested compounds were found more potent than Procaine amide\\textregistered and Lidocaine\\textregistered as positive antiarrhyth...

  20. Synthesis, reactions, and antiarrhythmic activities of some novel pyrimidines and pyridines fused with thiophene moiety

    OpenAIRE

    AMR, Abdel-Galil El-Sayed; ABDEL-HAFEZ, Naglaa Abdel-Samei; MOHAMED, Salwa Fahem; ABDALLA, Mohamed Mostafa

    2014-01-01

    We report herein the synthesis and antiarrhythmic activities of some newly synthesized heterocyclic theino[2,3-c]pyrimidine and theino[2,3-c]pyridine derivatives fused with thiophene moiety. Initially the acute toxicity of the compounds was assayed via the determination of their LD50. The antiarrhythmic activities for the compounds were determined and all the tested compounds were found more potent than Procaine amide\\textregistered and Lidocaine\\textregistered as positive antiarrhyth...

  1. The Synthesis of Novel 3-Substituted Poly(pyrroles) Bearing Crown-ether Moieties and a Study of their Electrochemical Properties

    DEFF Research Database (Denmark)

    Guernion, Nicolas J.L.; Blencowe, A.; Hayes, Wayne

    2006-01-01

    A series of fourteen novel pyrrole monomers substituted at the 3-position with aliphatic and aromatic crown-ether moieties have been synthesised in good yield and characterised extensively. Several of those compounds were electropolymerised successfully in acetonitrile, using both potentiostatic ...

  2. Synthesis and antiproliferative activity of novel limonene derivatives with a substituted thiourea moiety

    International Nuclear Information System (INIS)

    Figueiredo, Isis M.; Santos, Luciane V. dos; Costa, Willian F. da; Silva, Cleuza C. da; Sarragiotto, Maria H.; Carvalho, Joao E. de; Sacoman, Juliana L.; Kohn, Luciana K.

    2006-01-01

    A series of R-(+)-limonene derivatives bearing a substituted thiourea moiety (3-13) and five S-methyl analogs (14-18) were synthesized and evaluated for their in vitro antiproliferative activity against human cancer cell lines. Compounds bearing aromatic substituents (3-6) exhibit cytostatic activity in the full panel of cell lines tested, with GI 50 values in the range of 2.5 to 24 μmol L -1 . Compounds 3, 10, 12 and 16 were the most active with GI 5 )0 values in the range of 0.41 to 3.0 μmol L -1 , against different cell lines. (author)

  3. Controlled radical polymerization of an acrylamide containing L-alanine moiety via ATRP.

    Science.gov (United States)

    Rafiee, Zahra

    2016-02-01

    Homopolymerization of an optically active acrylamide having an amino acid moiety in the side chain, N-acryloyl-L-alanine (AAla) was carried out via atom transfer radical polymerization (ATRP) at room temperature using 2-hydroxyethyl-2'-methyl-2'-bromopropionate (HMB) or sodium-4-(bromomethyl)benzoate (SBB) as initiator in pure water, methanol/water mixture and pure methanol solvents. The polymerization reaction resulted in the optically active biocompatible amino acid-based homopolymer in good yield with narrow molecular weight distribution. The number average molecular weight increased with conversion and polydispersity was low. The structure and molecular weight of synthesized polymer were characterized by (1)H NMR, FT-IR spectroscopic techniques and size-exclusion chromatography.

  4. Cyclohexane/benzene organic glasses and ethylene/styrene copolymers behaviour under ionizing radiations: energy and species transfers between aliphatic and aromatic moieties

    International Nuclear Information System (INIS)

    Ferry, M.

    2008-11-01

    The aim of this study is to understand how aliphatic and aromatic groups interact under ionizing radiations. Three research orientations were explored: the determination of the relative contribution of energy and radical transfers, the determination of the intermolecular and intra-chain relative contribution, and the influence of the repartition of the aliphatic and aromatic units inside the polymer chain. Three systems composed of aromatic and aliphatic units were studied: the cyclohexane/benzene organic glasses (intermolecular reactions), the ethylene/styrene random copolymers (inter-chain and intra-chain reactions) and ethylene/styrene di-blocs copolymers (influence of the repartition of the aliphatic and aromatic units in the material). Considering the results obtained, we have concluded that energy transfers are important in the radiation protection effect of the aliphatic moiety by the aromatic one, although radical transfers are also contributing. Intermolecular transfers are efficient in the solid state and their efficiency seems equivalent to that of the intra-chain ones. Thanks to the use of infrared spectroscopy, we have shown an important effect of radiation sensitization of the aromatic moiety, whatever the irradiation temperature and the system studied: energy transfers to the aromatic moiety are carried out at the detriment of its stability. Finally, the repartition of the aliphatic and aromatic units in the polymer chain is not an important factor in the effects induced by the energy transfers. (author)

  5. Mesoporous silicas with covalently immobilized β-cyclodextrin moieties: synthesis, structure, and sorption properties

    Science.gov (United States)

    Roik, Nadiia V.; Belyakova, Lyudmila A.; Trofymchuk, Iryna M.; Dziazko, Marina O.; Oranska, Olena I.

    2017-09-01

    Mesoporous silicas with chemically attached macrocyclic moieties were successfully prepared by sol-gel condensation of tetraethyl orthosilicate and β-cyclodextrin-silane in the presence of a structure-directing agent. Introduction of β-cyclodextrin groups into the silica framework was confirmed by the results of IR spectral, thermogravimetric, and quantitative chemical analysis of surface compounds. The porous structure of the obtained materials was characterized by nitrogen adsorption-desorption measurements, powder X-ray diffraction, transmission electron microscopy, and dynamic light scattering. It was found that the composition of the reaction mixture used in β-cyclodextrin-silane synthesis significantly affects the structural parameters of the resulting silicas. The increase in (3-aminopropyl)triethoxysilane as well as the coupling agent content in relation to β-cyclodextrin leads ultimately to the lowering or complete loss of hexagonal arrangement of pore channels in the synthesized materials. Formation of hexagonally ordered mesoporous structure was observed at molar composition of the mixture 0.049 TEOS:0.001 β-CD-silane:0.007 CTMAB:0.27 NH4OH:7.2 H2O and equimolar ratio of components in β-CD-silane synthesis. The sorption of alizarin yellow on starting silica and synthesized materials with chemically attached β-cyclodextrin moieties was studied in phosphate buffer solutions with pH 7.0. Experimental results of the dye equilibrium sorption were analyzed using Langmuir, Freundlich, and Redlich-Peterson isotherm models. It was proved that the Redlich-Peterson isotherm model is the most appropriate for fitting the equilibrium sorption of alizarin yellow on parent silica with hexagonally arranged mesoporous structure as well as on modified one with chemically immobilized β-cyclodextrin groups. [Figure not available: see fulltext.

  6. Wittig Reaction: Domino Olefination and Stereoselectivity DFT Study. Synthesis of the Miharamycins' Bicyclic Sugar Moiety.

    Science.gov (United States)

    Cachatra, Vasco; Almeida, Andreia; Sardinha, João; Lucas, Susana D; Gomes, Ana; Vaz, Pedro D; Florêncio, M Helena; Nunes, Rafael; Vila-Viçosa, Diogo; Calhorda, Maria José; Rauter, Amélia P

    2015-11-20

    2-O-Acyl protected-d-ribo-3-uloses reacted with [(ethoxycarbonyl)methylene]triphenylphosphorane in acetonitrile to afford regio- and stereoselectively 2-(Z)-alkenes in 10-60 min under microwave irradiation. This domino reaction is proposed to proceed via tautomerization of 3-ulose to enol, acyl migration, tautomerization to the 3-O-acyl-2-ulose, and Wittig reaction. Alternatively, in chloroform, regioselective 3-olefination of 2-O-pivaloyl-3-uloses gave (E)-alkenes, key precursors for the miharamycins' bicyclic sugar moiety.

  7. Diamond surface functionalization with biomimicry - Amine surface tether and thiol moiety for electrochemical sensors

    Science.gov (United States)

    Sund, James B.; Causey, Corey P.; Wolter, Scott D.; Parker, Charles B.; Stoner, Brian R.; Toone, Eric J.; Glass, Jeffrey T.

    2014-05-01

    The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen-oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis.

  8. An efficient synthesis and spectroscopic characterization of Schiff bases containing 9,10-anthracenedione moiety

    Directory of Open Access Journals (Sweden)

    Fareed Ghulam

    2013-01-01

    Full Text Available A new method has been developed for the synthesis of novel Schiff bases containg anthraquinone moiety using dodeca-Tungstosilicic acid/P2O5 under solvent free conditions at room temperature. The reaction was completed in 1-3 minutes with excellent yields. This method was found to be more efficient, easy and hazardous free for the synthesis of azomethines. The development of these type of methadologies in synthetic chemistry may contribute to green chemistry. The structures of synthesized novel Schiff bases was elucidated using 1H-NMR, 13C-NMR, LCMS, FTIR and CHN analysis.

  9. Quantum mechanics models of the methanol dimer: O-H…O hydrogen bonds of ß-D-glucose moieties from crystallographic data.

    Science.gov (United States)

    In this study, a survey of the Cambridge Crystal Structure Database for all donor-acceptor interactions in ß-D-glucose moieties was performed to examine the similarities and differences among the different hydroxyl groups and ether oxygen atoms that participate in hydrogen bonds. Comparable behavior...

  10. Photo-triggered release from liposomes without membrane solubilization, based on binding to poly(vinyl alcohol) carrying a malachite green moiety.

    Science.gov (United States)

    Uda, Ryoko M; Kato, Yutaka; Takei, Michiko

    2016-10-01

    When working with liposomes analogous to cell membranes, it is important to develop substrates that can regulate interactions with the liposome surface in response to light. We achieved a photo-triggered release from liposomes by using a copolymer of poly(vinyl alcohol) carrying a malachite green moiety (PVAMG). Although PVAMG is a neutral polymer under dark conditions, it is photoionized upon exposure to UV light, resulting in the formation of a cationic site for binding to liposomes with a negatively charged surface. Under UV irradiation, PVAMG showed effective interaction with liposomes, releasing the encapsulated compound; however, this release was negligible under dark conditions. The poly(vinyl alcohol) moiety of PVAMG played an important role in the photo-triggered release. This release was caused by membrane destabilization without lipid solubilization. We also investigated different aspects of liposome/PVAMG interactions, including PVAMG-induced fusion between the liposomes and the change in the liposome morphologies. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Blue Light Emitting Polyphenylene Dendrimers with Bipolar Charge Transport Moieties

    Directory of Open Access Journals (Sweden)

    Guang Zhang

    2016-10-01

    Full Text Available Two light-emitting polyphenylene dendrimers with both hole and electron transporting moieties were synthesized and characterized. Both molecules exhibited pure blue emission solely from the pyrene core and efficient surface-to-core energy transfers when characterized in a nonpolar environment. In particular, the carbazole- and oxadiazole-functionalized dendrimer (D1 manifested a pure blue emission from the pyrene core without showing intramolecular charge transfer (ICT in environments with increasing polarity. On the other hand, the triphenylamine- and oxadiazole-functionalized one (D2 displayed notable ICT with dual emission from both the core and an ICT state in highly polar solvents. D1, in a three-layer organic light emitting diode (OLED by solution processing gave a pure blue emission with Commission Internationale de l’Éclairage 1931 CIE xy = (0.16, 0.12, a peak current efficiency of 0.21 cd/A and a peak luminance of 2700 cd/m2. This represents the first reported pure blue dendrimer emitter with bipolar charge transport and surface-to-core energy transfer in OLEDs.

  12. Blue Light Emitting Polyphenylene Dendrimers with Bipolar Charge Transport Moieties.

    Science.gov (United States)

    Zhang, Guang; Auer-Berger, Manuel; Gehrig, Dominik W; Blom, Paul W M; Baumgarten, Martin; Schollmeyer, Dieter; List-Kratochvil, E J W; Müllen, Klaus

    2016-10-20

    Two light-emitting polyphenylene dendrimers with both hole and electron transporting moieties were synthesized and characterized. Both molecules exhibited pure blue emission solely from the pyrene core and efficient surface-to-core energy transfers when characterized in a nonpolar environment. In particular, the carbazole- and oxadiazole-functionalized dendrimer ( D1 ) manifested a pure blue emission from the pyrene core without showing intramolecular charge transfer (ICT) in environments with increasing polarity. On the other hand, the triphenylamine- and oxadiazole-functionalized one ( D2 ) displayed notable ICT with dual emission from both the core and an ICT state in highly polar solvents. D1 , in a three-layer organic light emitting diode (OLED) by solution processing gave a pure blue emission with Commission Internationale de l'Éclairage 1931 CIE xy = (0.16, 0.12), a peak current efficiency of 0.21 cd/A and a peak luminance of 2700 cd/m². This represents the first reported pure blue dendrimer emitter with bipolar charge transport and surface-to-core energy transfer in OLEDs.

  13. Polypeptide nanogels with hydrophobic moieties in the cross-linked ionic cores: Synthesis, characterization and implications for anticancer drug delivery

    Science.gov (United States)

    Kim, Jong Oh; Oberoi, Hardeep S.; Desale, Swapnil; Kabanov, Alexander V.; Bronich, Tatiana K.

    2014-01-01

    Polymer nanogels have gained considerable attention as a potential platform for drug delivery applications. Here we describe the design and synthesis of novel polypeptide-based nanogels with hydrophobic moieties in the cross-linked ionic cores. Diblock copolymer, poly(ethylene glycol)-b-poly(L-glutamic acid), hydrophobically modified with L-phenylalanine methyl ester moieties was used for controlled template synthesis of nanogels with small size (ca. 70 nm in diameter) and narrow particle size distribution. Steady-state and time-resolved fluorescence studies using coumarin C153 indicated the existence of hydrophobic domains in the ionic cores of the nanogels. Stable doxorubicin-loaded nanogels were prepared at high drug capacity (30 w/w%). We show that nanogels are enzymatically-degradable leading to accelerated drug release under simulated lysosomal acidic pH. Furthermore, we demonstrate that the nanogel-based formulation of doxorubicin is well tolerated and exhibit an improved antitumor activity compared to a free doxorubicin in an ovarian tumor xenograft mouse model. Our results signify the point to a potential of these biodegradable nanogels as attractive carriers for delivery of chemotherapeutics. PMID:23998716

  14. Pharmaceutical micelles featured with singlet oxygen-responsive cargo release and mitochondrial targeting for enhanced photodynamic therapy

    Science.gov (United States)

    Zhang, Xin; Yan, Qi; Naer Mulatihan, Di; Zhu, Jundong; Fan, Aiping; Wang, Zheng; Zhao, Yanjun

    2018-06-01

    The efficacy of nanoparticulate photodynamic therapy is often compromised by the short life time and limited diffusion radius of singlet oxygen as well as uncontrolled intracellular distribution of photosensitizer. It was hypothesized that rapid photosensitizer release upon nanoparticle internalization and its preferred accumulation in mitochondria would address the above problems. Hence, the aim of this study was to engineer a multifunctional micellar nanosystem featured with singlet oxygen-responsive cargo release and mitochondria-targeting. An imidazole-bearing amphiphilic copolymer was employed as the micelle building block to encapsulate triphenylphosphonium-pyropheophorbide a (TPP-PPa) conjugate or PPa. Upon laser irradiation, the singlet oxygen produced by TPP-PPa/PPa oxidized the imidazole moiety to produce hydrophilic urea, leading to micelle disassembly and rapid cargo release. The co-localization analysis showed that the TPP moiety significantly enhanced the photosensitizer uptake by mitochondria, improved mitochondria depolarization upon irradiation, and hence boosted the cytotoxicity in 4T1 cells. The targeting strategy also dramatically reduced the intracellular ATP concentration as a consequence of mitochondria injury. The mitochondria damage was accompanied with the activation of the apoptosis signals (caspase 3 and caspase 9), whose level was directly correlated to the apoptosis extent. The current work provides a facile and robust means to enhance the efficacy of photodynamic therapy.

  15. Synthesis and antitumor evaluation of thiophene based azo dyes incorporating pyrazolone moiety

    Directory of Open Access Journals (Sweden)

    Moustafa A. Gouda

    2016-03-01

    Full Text Available A series of thiophene incorporating pyrazolone moieties 5a–f and 6a–c were synthesized via diazo coupling of diazonium salt of 3-substituted-2-amino-4,5,6,7-tetrahydrobenzo[b]thiophenes 1a–c with 3-methyl-1H-pyrazol-5(4H-one, 3-methyl-1-phenyl-1H-pyrazol-5(4H-one or 3-amino-1H-pyrazol-5(4H-one, respectively. Newly synthesized dyes were applied to polyester fabric as disperse dyes in which their color measurements and fastness properties were evaluated. These dyes showed generally red to blue shifted color with high extinction coefficient in comparison with aniline-based azo dyes. The antitumor activity of the synthesized dyes was evaluated. The results showed clearly that most of them exhibited good activity and compounds 5c and 5d exhibited moderate activity.

  16. Muscle-type nicotinic receptor modulation by 2,6-dimethylaniline, a molecule resembling the hydrophobic moiety of lidocaine

    Directory of Open Access Journals (Sweden)

    Armando Alberola-Die

    2016-11-01

    Full Text Available To identify the molecular determinants responsible for lidocaine blockade of muscle-type nAChRs, we have studied the effects on this receptor of 2,6-dimethylaniline (DMA, which resembles lidocaine’s hydrophobic moiety. Torpedo marmorata nAChRs were microtransplanted to Xenopus oocytes and currents elicited by ACh (IACh, either alone or co-applied with DMA, were recorded. DMA reversibly blocked IACh and, similarly to lidocaine, exerted a closed-channel blockade, as evidenced by the enhancement of IACh blockade when DMA was pre-applied before its co-application with ACh, and hastened IACh decay. However, there were marked differences among its mechanisms of nAChR inhibition and those mediated by either the entire lidocaine molecule or diethylamine (DEA, a small amine resembling lidocaine’s hydrophilic moiety. Thereby, the IC50 for DMA, estimated from the dose-inhibition curve, was in the millimolar range, which is one order of magnitude higher than that for either DEA or lidocaine. Besides, nAChR blockade by DMA was voltage-independent in contrast to the increase of IACh inhibition at negative potentials caused by the more polar lidocaine or DEA molecules. Accordingly, virtual docking assays of DMA on nAChRs showed that this molecule binds predominantly at intersubunit crevices of the transmembrane-spanning domain, but also at the extracellular domain. Furthermore, DMA interacted with residues inside the channel pore, although only in the open-channel conformation. Interestingly, co-application of ACh with DEA and DMA, at their IC50s, had additive inhibitory effects on IACh and the extent of blockade was similar to that predicted by the allotopic model of interaction, suggesting that DEA and DMA bind to nAChRs at different loci. These results indicate that DMA mainly mimics the low potency and non-competitive actions of lidocaine on nAChRs, as opposed to the high potency and voltage-dependent block by lidocaine, which is emulated by the

  17. Triphenylphosphonium Moiety Modulates Proteolytic Stability and Potentiates Neuroprotective Activity of Antioxidant Tetrapeptides in Vitro

    Directory of Open Access Journals (Sweden)

    Rezeda A. Akhmadishina

    2018-02-01

    Full Text Available Although delocalized lipophilic cations have been identified as effective cellular and mitochondrial carriers for a range of natural and synthetic drug molecules, little is known about their effects on pharmacological properties of peptides. The effect of triphenylphosphonium (TPP cation on bioactivity of antioxidant tetrapeptides based on the model opioid YRFK motif was studied. Two tetrapeptide variants with L-arginine (YRFK and D-arginine (YrFK were synthesized and coupled with carboxyethyl-TPP (TPP-3 and carboxypentyl-TPP (TPP-6 units. The TPP moiety noticeably promoted YRFK cleavage by trypsin, but effectively prevented digestion of more resistant YrFK attributed, respectively, to structure-organizing and shielding effects of the TPP cation on conformational variants of the tetrapeptide motif. The TPP moiety enhanced radical scavenging activity of the modified YRFK in a model Fenton-like reaction, whereas decreased reactivity was revealed for both YrFK and its TPP derivative. The starting motifs and modified oligopeptides, especially the TPP-6 derivatives, suppressed acute oxidative stress in neuronal PC-12 cells during a brief exposure similarly with glutathione. The effect of oligopeptides was compared upon culturing of PC-12 cells with CoCl2, L-glutamic acid, or menadione to mimic physiologically relevant oxidative states. The cytoprotective activity of oligopeptides significantly depended on the type of oxidative factor, order of treatment and peptide structure. Pronounced cell-protective effect was established for the TPP-modified oligopeptides, which surpassed that of the unmodified motifs. The protease-resistant TPP-modified YrFK showed the highest activity when administered 24 h prior to the cell damage. Our results suggest that the TPP cation can be used as a modifier for small therapeutic peptides to improve their pharmacokinetic and pharmacological properties.

  18. Uranium(VI) adsorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety

    International Nuclear Information System (INIS)

    Matsuda, Masaaki; Akiyoshi, Yoshirou

    1991-01-01

    Uranium(VI) adsorption and desorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety of 2.29 mmol/g-resin (APA) were examined. Uranium(VI) adsorption properties of several ion exchange resins and extractant agents which were known as excellent adsorbents for uranium(VI), were examined together for a comparison with those of APA. Uranium(VI) adsorption capacity of APA at the concentration of 100 mg·dm -3 -uranium(VI) in 100 g·dm -3 -H 2 SO 4 aq. soln., 190 g·dm -3 -H 3 PO 4 aq. soln. and uranium enriched sea water, was 0.2, 0.05 and 0.05 mmol·g -1 respectively. The adsorption capacity of APA for uranium(VI) in these solutions was larger than that of another adsorbents, except the adsorption of uranium(VI) in enriched sea water on ion exchange resin containing phosphoric acid moiety (adsorption capacity ; 0.2 mmol·g -1 ). Uranium(VI) adsorption rate on APA was high and the relation between treatment time (t : min) and uranium(VI) concentration (y : mg·dm -3 ) in 100 g·dm -3 H 2 SO 4 aq. soln. after treatment, was shown as following equation, y=20 0.048t+1.90 (0≤t≤30). The adsorbed uranium(VI) on APA was able to be eluted with a mixed aq. soln. of hydrogen peroxide and sodium hydroxide and also was able to be eluted with an aq. alkaline soln. dissolved reduction agents such as sodium sulfite and hydrazine. From these results, it was thought that uranium(VI) adsorbed on APA was eluted due to the reduction to uranium(VI) by these eluents. (author)

  19. The Human Skin Barrier Is Organized as Stacked Bilayers of Fully Extended Ceramides with Cholesterol Molecules Associated with the Ceramide Sphingoid Moiety

    DEFF Research Database (Denmark)

    Iwai, Ichiro; Han, Hongmei; Hollander, Lianne den

    2012-01-01

    not previously described in a biological system-stacked bilayers of fully extended ceramides (CERs) with cholesterol molecules associated with the CER sphingoid moiety. This arrangement rationalizes the skin's low permeability toward water and toward hydrophilic and lipophilic substances, as well as the skin...

  20. Insights into the structure-activity relationship of the anticancer compound ZJ-101, a derivative of marine natural product superstolide A: A role played by the lactone moiety.

    Science.gov (United States)

    Qiu, Haibo; Qian, Shan; Head, Sarah A; Liu, Jun O; Jin, Zhendong

    2016-10-01

    Compound ZJ-101, a structurally simplified analog of the marine natural product superstolide A, was previously developed in our laboratory. In the subsequent structure-activity relationship study, a new analog ZJ-109 was designed and synthesized to probe the importance of the lactone moiety of the molecule by replacing the lactone in ZJ-101 with a lactam. The biological evaluation showed that ZJ-109 is about 8-12 times less active against cancer cells in vitro than ZJ-101, suggesting that the lactone moiety of the molecule is important for its anticancer activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. One-Pot Multicomponent Synthesis of Thiourea Derivatives in Cyclotriphosphazenes Moieties

    Directory of Open Access Journals (Sweden)

    Zainab Ngaini

    2017-01-01

    Full Text Available In this study, hexasubstituted thiourea was carried out via reaction of isothiocyanato cyclophosphazene intermediates with a series of aromatics amines and amino acids in a one-pot reaction system. The reaction was not as straightforward as typical thiourea synthesis. Six unexpected thiourea derivatives 3a–f were formed in the presence of cyclotriphosphazene moieties in good yields (53–82%. The structures of 3a–f were characterized by elemental analysis and FTIR, 1H, 13C, and 31P NMR spectroscopies. The occurrence of reverse thioureas formation in a one-pot reaction system is discussed. The possible binding interaction of the synthesised thiourea 3a-b in comparison to the predicted phenyl thiourea 5a-b and the targeted 4a with enzyme enoyl ACP reductase (FabI is also discussed. Molecular docking of the targeted hexasubstituted thiourea 4a is able to give higher binding affinity of −7.5 kcal/mol compared to 5a-b (−5.9 kcal/mol and −6.3 kcal/mol and thiourea 3a-b (−4.5 kcal/mol and −4.7 Kcal/mol.

  2. Turnover and metabolism of phosphatidylglycerol acyl moieties in E. coli

    International Nuclear Information System (INIS)

    Cooper, C.L.; Rock, C.O.

    1987-01-01

    Fatty acids synthesized in mutants (plsB) blocked in de novo phospholipid biosynthesis were preferentially transferred to phosphatidylglycerol (PtdGro). The ratio of phospholipid species labeled with 32 P and [ 3 H]acetate in the absence of glycerol-3-P acyltransferase activity indicated that [ 3 H]acetate incorporation into PtdGro was due to fatty acid turnover. The magnitude of the turnover process was difficult to estimate due to a significant contraction of the acetyl-CoA pool following the inhibition of phospholipid synthesis. A possible connection between PtdGro turnover and protein acylation was investigated in an E. coli strain containing a lipoprotein expression vector. Cells were prelabeled with [ 3 H]acetate and lipoprotein expression was induced concomitant with the addition of exogenous [ 14 C]-palmitate. [ 14 C] Palmitate was assimilated into the l-position of phosphatidylethanolamine and transferred to the amino terminus of the lipoprotein. In contrast, the ester-linked lipoprotein fatty acids and PtdGro were not enriched in carbon-14 implying a metabolic relationship between these two pools. The data suggest that turnover of PtdGro acyl moieties is related to protein acylation, but a direct link between the two processes remains to be established

  3. Enhancement of Ag-Based Plasmonic Photocatalysis in Hydrogen Production from Ammonia Borane by the Assistance of Single-Site Ti-Oxide Moieties within a Silica Framework.

    Science.gov (United States)

    Verma, Priyanka; Kuwahara, Yasutaka; Mori, Kohsuke; Yamashita, Hiromi

    2017-03-13

    Ag nanoparticles (NPs) have gained great attention owing to their interesting plasmonic properties and efficient catalysis under visible-light irradiation. In this study, an Ag-based plasmonic catalyst supported on mesoporous silica with isolated and tetrahedrally coordinated single-site Ti-oxide moieties, namely, Ag/Ti-SBA-15, was designed with the purpose of utilizing the broad spectral range of solar energy. The Ti-SBA-15 support allows the deposition of small Ag NPs with a narrow size distribution. The chemical structure, morphology, and optical properties of the prepared catalyst were characterized by techniques such as UV/Vis, FT extended X-ray absorption fine structure, and X-ray photoelectron spectroscopy, field-emission SEM, TEM, and N 2 physisorption studies. The catalytic activity of Ag/Ti-SBA-15 in hydrogen production from ammonia borane by hydrolysis was significantly enhanced in comparison with Ag/SBA-15 without Ti-oxide moieties and Ag/TiO 2 /SBA-15 involving agglomerated TiO 2 , both in the dark and under light irradiation. Improved electron transfer under light irradiation caused by the creation of heterojunctions between Ag NPs and Ti-oxide moieties explains the results obtained in the present study. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Systematic Moiety Variations of Ultrashort Peptides Produce Profound Effects on Self-Assembly, Nanostructure Formation, Hydrogelation, and Phase Transition

    KAUST Repository

    Chan, Kiat Hwa

    2017-10-04

    Self-assembly of small biomolecules is a prevalent phenomenon that is increasingly being recognised to hold the key to building complex structures from simple monomeric units. Small peptides, in particular ultrashort peptides containing up to seven amino acids, for which our laboratory has found many biomedical applications, exhibit immense potential in this regard. For next-generation applications, more intricate control is required over the self-assembly processes. We seek to find out how subtle moiety variation of peptides can affect self-assembly and nanostructure formation. To this end, we have selected a library of 54 tripeptides, derived from systematic moiety variations from seven tripeptides. Our study reveals that subtle structural changes in the tripeptides can exert profound effects on self-assembly, nanostructure formation, hydrogelation, and even phase transition of peptide nanostructures. By comparing the X-ray crystal structures of two tripeptides, acetylated leucine-leucine-glutamic acid (Ac-LLE) and acetylated tyrosine-leucine-aspartic acid (Ac-YLD), we obtained valuable insights into the structural factors that can influence the formation of supramolecular peptide structures. We believe that our results have major implications on the understanding of the factors that affect peptide self-assembly. In addition, our findings can potentially assist current computational efforts to predict and design self-assembling peptide systems for diverse biomedical applications.

  5. New Flame-Retardant Poly(ester-imide)s Containing Phosphine Oxide Moieties in the Main Chain: Synthesis and Properties

    OpenAIRE

    FAGHIHI, Khalil

    2014-01-01

    Six new flame-retardant poly(ester-imide)s (9a-f) with high inherent viscosity and containing phosphine oxide moieties in the main chain were synthesized from the polycondensation reaction of N,N-(3,3-diphenylphenyl phosphine oxide) bistrimellitimide diacid chloride (7) with 6 aromatic diols (8a-f) by 2 different methods:--solution and microwave-assisted polycondensation. The results showed that compared to solution polycondensation, the microwave-assisted polycondensation reaction us...

  6. Small endogenous molecules as moiety to improve targeting of CNS drugs.

    Science.gov (United States)

    Sutera, Flavia Maria; De Caro, Viviana; Giannola, Libero Italo

    2017-01-01

    A major challenge in the development of novel neuro-therapeutic agents is to effectively overcome the blood-brain barrier (BBB), which acts as a 'working dynamic barrier'. The core problem in the treatment of neurodegenerative diseases is failed delivery of potential medicines due to their inadequate permeation rate. Areas covered: The present review gives a summary of endogenous moieties used in synthesizing prodrugs, derivatives and bioisosteric drugs appositely designed to structurally resemble physiological molecular entities able to be passively absorbed or carried by specific carrier proteins expressed at BBB level. In particular, this overview focuses on aminoacidic, glycosyl, purinergic, ureic and acidic fragments derivatives, most of which can take advantage from BBB carrier-mediated transporters, where passive diffusion is not permitted. Expert opinion: In the authors' perspective, further progress in this field could expedite successful translation of new chemical entities into clinical trials. Careful rationalization of the linkage between endogenous molecular structures and putative transporters binding sites could allow to useful work-flows and libraries for synthesizing new BBB-crossing therapeutic substances and/or multifunctional drugs for treatments of central disorders.

  7. Control of cell function on a phospholipid polymer having phenylboronic acid moiety

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Aya; Ishihara, Kazuhiko [Department of Materials Engineering, School of Engineering, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Konno, Tomohiro [Center for NanoBio Integration, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ikake, Hiroki; Kurita, Kimio, E-mail: konno@bioeng.t.u-tokyo.ac.j [Department of Materials and Applied Chemistry, Graduate School of Science and Technology, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan)

    2010-10-01

    We synthesized a water-insoluble phospholipid polymer bearing a phenylboronic acid moiety (PMBV), which induces cell adhesion through a specific interaction with the glycoprotein, fibronectin. Surface plasmon resonance analysis revealed that fibronectin was adsorbed on the PMBV surface. When fibroblasts were cultured on the PMBV surface, the cells adhered and proliferated normally while showing a spherical morphology. In addition, the adherent cells were able to detach after the addition of sugar molecules, which bound to phenylboronic acid through an exchange reaction. The cell cycle of adherent cells was evaluated with the embedded HeLa-Fucci cells by using a fluorescent ubiquitination-based cell cycle indicator. The cell-cycle analysis by fluorescence microscopy indicated that the adherent HeLa-Fucci cells tended to converge to the G1 phase. The differentiation of mesenchymal stem cells to chondrocytes was accelerated on PMBV in the presence of bone morphogenetic protein-2. We concluded that PMBV is a useful surface in experiments for assessing cellular function and differentiation.

  8. The effect of albumin on podocytes: The role of the fatty acid moiety and the potential role of CD36 scavenger receptor

    International Nuclear Information System (INIS)

    Pawluczyk, I.Z.A.; Pervez, A.; Ghaderi Najafabadi, M.; Saleem, M.A.; Topham, P.S.

    2014-01-01

    Evidence is emerging that podocytes are able to endocytose proteins such as albumin using kinetics consistent with a receptor-mediated process. To date the role of the fatty acid moiety on albumin uptake kinetics has not been delineated and the receptor responsible for uptake is yet to be identified. Albumin uptake studies were carried out on cultured human podocytes exposed to FITC-labelled human serum albumin either carrying fatty acids (HSA +FA ) or depleted of them (HSA −FA ). Receptor-mediated endocytosis of FITC-HSA +FA over 60 min was 5 times greater than that of FITC-HSA −FA . 24 h exposure of podocytes to albumin up-regulated nephrin expression and induced the activation of caspase-3. These effects were more pronounced in response to HSA −FA. Individually, anti-CD36 antibodies had no effect upon endocytosis of FITC-HSA. However, a cocktail of 2 antibodies reduced uptake by nearly 50%. Albumin endocytosis was enhanced in the presence of the CD36 specific inhibitor sulfo-N-succinimidyl oleate (SSO) while knock-down of CD36 using CD36siRNA had no effect on uptake. These data suggest that receptor-mediated endocytosis of albumin by podocytes is regulated by the fatty acid moiety, although, some of the detrimental effects are induced independently of it. CD36 does not play a direct role in the uptake of albumin. - Highlights: • The fatty acid moiety is essential for receptor mediated endocytosis of albumin. • Fatty acid depleted albumin is more pathogenic to podocytes. • CD36 is not directly involved in albumin uptake by podocytes

  9. Enhancing photophysical and photochemical properties of zinc(II) phthalocyanine dyes by substitution of triptycene moieties

    Energy Technology Data Exchange (ETDEWEB)

    Al-Sohaimi, Bander Roshadan [Department of Chemistry, Faculty of Science, Taibah University, P.O. Box 344, Al-Madinah Al Munawwrah (Saudi Arabia); Pişkin, Mehmet [Çanakkale Onsekiz Mart University, Vocational School of Technical Sciences, Department of Food Technology, Çanakkale 17100 (Turkey); Aljuhani, Ateyatallah; Al-Raqa, Shaya Y. [Department of Chemistry, Faculty of Science, Taibah University, P.O. Box 344, Al-Madinah Al Munawwrah (Saudi Arabia); Durmuş, Mahmut, E-mail: durmus@gtu.edu.tr [Gebze Technical University, Department of Chemistry, P.O. Box 141, Gebze 41400, Kocaeli (Turkey)

    2016-05-15

    The symmetrical zinc(II) phthalocyanines conjugated with 9,10-dioctyl-6,7-dimethoxy-2,3-dioxytriptycene or 9,10-diundecyl-6,7-dimethoxy-2,3-dioxytriptycene moieties were synthesized in this study. These novel phthalocyanines were characterized by standard characterization techniques such as {sup 1}H-NMR, FT-IR, UV–vis, Mass and Elemental Analysis. All these phthalocyanines showed highly solubility and formed non-aggregated monomeric species in most of the organic solvents. Their photochemical properties such as singlet oxygen, and photodegradation quantum yields, and photophysical properties including fluorescence quantum yields and lifetimes were investigated in toluene. The fluorescence quenching behavior of the studied zinc(II) phthalocyanines by the addition of 1,4-benzoquinone were also described in toluene.

  10. Enhancing photophysical and photochemical properties of zinc(II) phthalocyanine dyes by substitution of triptycene moieties

    International Nuclear Information System (INIS)

    Al-Sohaimi, Bander Roshadan; Pişkin, Mehmet; Aljuhani, Ateyatallah; Al-Raqa, Shaya Y.; Durmuş, Mahmut

    2016-01-01

    The symmetrical zinc(II) phthalocyanines conjugated with 9,10-dioctyl-6,7-dimethoxy-2,3-dioxytriptycene or 9,10-diundecyl-6,7-dimethoxy-2,3-dioxytriptycene moieties were synthesized in this study. These novel phthalocyanines were characterized by standard characterization techniques such as 1 H-NMR, FT-IR, UV–vis, Mass and Elemental Analysis. All these phthalocyanines showed highly solubility and formed non-aggregated monomeric species in most of the organic solvents. Their photochemical properties such as singlet oxygen, and photodegradation quantum yields, and photophysical properties including fluorescence quantum yields and lifetimes were investigated in toluene. The fluorescence quenching behavior of the studied zinc(II) phthalocyanines by the addition of 1,4-benzoquinone were also described in toluene.

  11. Light-harvesting features revealed by the structure of plant Photosystem I

    CERN Document Server

    Ben-Shem, A; Nelson, N; 10.1023/B:PRES.0000036881.23512.42

    2004-01-01

    Oxygenic photosynthesis is driven by two multi-subunit membrane protein complexes, Photosystem I and Photosystem II. In plants and green algae, both complexes are composed of two moieties: a reaction center (RC), where light-induced charge translocation occurs, and a peripheral antenna that absorbs light and funnels its energy to the reaction center. The peripheral antenna of PS I (LHC I) is composed of four gene products (Lhca 1-4) that are unique among the chlorophyll a/b binding proteins in their pronounced long-wavelength absorbance and in their assembly into dimers. The recently determined structure of plant Photosystem I provides the first relatively high- resolution structural model of a super-complex containing a reaction center and its peripheral antenna. We describe some of the structural features responsible for the unique properties of LHC I and discuss the advantages of the particular LHC I dimerization mode over monomeric or trimeric forms. In addition, we delineate some of the interactions betw...

  12. Photoconducting hybrid perovskite containing carbazole moiety as the organic layer: Fabrication and characterization

    International Nuclear Information System (INIS)

    Deng Meng; Wu Gang; Cheng Siyuan; Wang Mang; Borghs, Gustaaf; Chen Hongzheng

    2008-01-01

    PbCl 2 -based thin films of perovskite structure with hole-transporting carbazole derivatives as the organic layer were successfully prepared by spin-coating from dimethylformamide solution containing stoichiometric amounts of organic and inorganic moieties. The crystal structure and optical property of the hybrid perovskite were characterized by Fourier transform infrared (FT-IR) spectrum, X-ray diffraction (XRD), UV-vis absorption and photoluminescence (PL). FT-IR spectra confirmed the formation of organic-inorganic hybrid perovskite structure. UV-vis spectra of hybrid perovskite thin films exhibited a wide absorption band in ultraviolet region as well as a sharp peak at 330 nm characteristic of PbCl 2 -based layered perovskite. X-ray diffraction profiles indicated that the layered structure was oriented parallel to the silica glass slide plane. Meanwhile, double-layer photoreceptors of the hybrid perovskite were also fabricated, which showed the enhancement of photoconductivity by carbazole chromophore

  13. Specific membrane binding of factor VIII is mediated by O-phospho-L-serine, a moiety of phosphatidylserine.

    Science.gov (United States)

    Gilbert, G E; Drinkwater, D

    1993-09-21

    Phosphatidylserine, a negatively charged lipid, is exposed on the platelet membrane following cell stimulation, correlating with the expression of factor VIII receptors. We have explored the importance of the negative electrostatic potential of phosphatidylserine vs chemical moieties of phosphatidylserine for specific membrane binding of factor VIII. Fluorescein-labeled factor VIII bound to membranes containing 15% phosphatidic acid, a negatively charged phospholipid, with low affinity compared to phosphatidylserine-containing membranes. Binding was not specific as it was inhibited by other proteins in plasma. Factor VIII bound to membranes containing 10% phosphatidylserine in spite of a varying net charge provided by 0-15% stearylamine, a positively charged lipid. The soluble phosphatidylserine moiety, O-phospho-L-serine, inhibited factor VIII binding to phosphatidylserine-containing membranes with a Ki of 20 mM, but the stereoisomer, O-phospho-D-serine, was 5-fold less effective. Furthermore, binding of factor VIII to membranes containing synthetic phosphatidyl-D-serine was 5-fold less than binding to membranes containing phosphatidyl-L-serine. Membranes containing synthetic phosphatidyl-L-homoserine, differing from phosphatidylserine by a single methylene, supported high-affinity binding, but it was not specific as factor VIII was displaced by other plasma proteins. O-Phospho-L-serine also inhibited the binding of factor VIII to platelet-derived microparticles with a Ki of 20 mM, and the stereoisomer was 4-fold less effective. These results indicate that membrane binding of factor VIII is mediated by a stereoselective recognition O-phospho-L-serine of phosphatidylserine and that negative electrostatic potential is of lesser importance.

  14. Synthesis, structural characterization and photoluminescence properties of rhenium(I) complexes based on bipyridine derivatives with carbazole moieties.

    Science.gov (United States)

    Li, Hong-Yan; Wu, Jing; Zhou, Xin-Hui; Kang, Ling-Chen; Li, Dong-Ping; Sui, Yan; Zhou, Yong-Hui; Zheng, You-Xuan; Zuo, Jing-Lin; You, Xiao-Zeng

    2009-12-21

    Three N,N-bidentate ligands, 5,5'-dibromo-2,2-bipyridine (L1) and two carbazole containing ligands of 5-bromo-5'-carbazolyl-2,2-bipyridine (L2), 5,5'-dicarbazolyl-2,2'-bipyridine (L3), and their corresponding rhenium Re(CO)3Cl(L) complexes (ReL1-ReL3) have been successfully synthesized and characterized by elemental analysis, 1H NMR and IR spectra. Their photophysical properties and thermal analysis, along with the X-ray crystal structure analysis of L3 and complexes ReL1 and ReL3 are also described. In CH2Cl2 solution at room temperature, all complexes display intense absorption bands at ca. 220-350 nm, which can be assigned to spin-allowed intraligand (pi-->pi*) transitions, and the low energy broad bands in the 360-480 nm region are attributed to the metal to ligand charge-transfer d(Re)-->pi* (diimine) (MLCT). The introduction of carbazole moieties improves the MLCT absorption and molar extinction coefficient of these complexes. Upon excitation at the peak maxima, all complexes show strong emissions around 620 nm, which are assigned to d(Re)-->pi* (diimine) MLCT phosphorescence. The photoluminescence lifetime decay of Re(I) complexes were measured and the quantum efficiencies of the rhenium(I) complexes were calculated by using air-equilibrated [Ru(bpy)3]2+ x 2 Cl- aqueous solution as standard (phi(std) = 0.028). The complexes with appended carbazole moieties exhibit enhanced luminescence performances relative to ReL1.

  15. Comparison of Separation of Seed Oil Triglycerides Containing Isomeric Conjugated Octadecatrienoic Acid Moieties by Reversed-Phase HPLC

    Directory of Open Access Journals (Sweden)

    Anh Van Nguyen

    2017-12-01

    Full Text Available Relative retention analysis and increment approach were applied for the comparison of triglycerides (TGs retention of a broad set of plant seed oils with isomeric conjugated octadecatrienoic acids (CLnA by reversed-phase HPLC for “propanol-2-acetonitrile” mobile phases and Kromasil 100-5C18 stationary phase with diode array detection (DAD and mass spectrometric (MS detection. The subjects of investigation were TGs of seed oils: Calendula officinalis, Catalpa ovata, Jacaranda mimosifolia, Centranthus ruber, Momordica charantia, Trichosanthes anguina, Punica granatum, Thladiantha dubia, Valeriana officinalis, and Vernicia montana. It was found that a sequence of elution of TGs of the same types is the same without any inversions for full range of mobile phase compositions: punicic (C18:39Z11E13Z < jacaric (C18:38Z10E12Z < catalpic (C18:39E11E13Z < α-eleostearic (C18:39Z11E13E < calendic (C18:38E10E12Z < β-eleostearic (C18:39E11E13E < all-E calendic (C18:38E10E12E acids. TGs and fatty acid compositions were calculated for all oil samples. Regularities of solute retentions as a function of isomeric conjugated octadecatrienoic acid moiety structure are discussed. Thus, it was proven that it is possible to differentiate TGs of complex composition with moieties of all natural CLnA by retention control accomplished by electronic spectra comparison, even though there are only three types of electronic-vibration spectra for seven isomeric CLnA.

  16. Improvement of thermal properties and flame retardancy of epoxy-amine thermosets by introducing bisphenol containing azomethine moiety

    Directory of Open Access Journals (Sweden)

    2007-05-01

    Full Text Available A novel bisphenol 1, 4'-bis{4-[(4-hydroxy phenyliminomethylidene] phenoxy} benzene (BHPB, which contains azomethine moiety and flexible aromatic ether linkage, was synthesized and introduced into the curing system composed of diglycidyl ether of bisphenol A (DGEBA and diamine. The curing behavior of DGEBA/diamine changed dramatically due to the introduction of BHPB. The resultant epoxy thermosets containing BHPB had high Tgs (127-160 °C, high Td, 5% (>=330°C and high integral procedure decomposition temperature (IPDT values (662-1230°C and good flame retardancy for their high Limited Oxygen Index (LOI values (above 29.5.

  17. Design of α-S-Neoglycopeptides Derived from MUC1 with a Flexible and Solvent-Exposed Sugar Moiety

    DEFF Research Database (Denmark)

    Rojas-Ocáriz, Víctor; Compañón, Ismael; Aydillo Miguel, Carlos

    2016-01-01

    in solution have been evaluated by combining NMR experiments and molecular dynamics simulations. The linker plays a key role in the modulation of the conformation of these compounds at different levels, blocking a direct contact between the sugar moiety and the backbone, promoting a helix-like conformation...... for the glycosylated residue and favoring the proper presentation of the sugar unit for molecular recognition events. The feasibility of these novel compounds as mimics of MUC1 antigens has been validated by the X-ray diffraction structure of one of these unnatural derivatives complexed to an anti-MUC1 monoclonal...

  18. Role of the p-Coumaroyl Moiety in the Antioxidant and Cytoprotective Effects of Flavonoid Glycosides: Comparison of Astragalin and Tiliroside

    Directory of Open Access Journals (Sweden)

    Xican Li

    2017-07-01

    Full Text Available The aim of this study was to explore the role of p-coumaroyl in the antioxidant and cytoprotective effects of flavonoid glycosides. The antioxidant effects of astragalin and tiliroside were compared using ferric ion reducing antioxidant power, DPPH• scavenging, ABTS•+ scavenging, •O2– scavenging, and Fe2+-chelating assays. The results of these assays revealed that astragalin and tiliroside both exhibited dose-dependent activities; however, tiliroside exhibited lower IC50 values than astragalin. In the Fe2+-chelating assay, tiliroside gave a larger shoulder-peak at 510 nm than astragalin, and was also found to be darker in color. Both of these compounds were subsequently evaluated in a Fenton-induced mesenchymal stem cell (MSC damaged assay, where tiliroside performed more effectively as a cytoprotective agent than astragalin. Tiliroside bearing a 6′′-O-p-coumaroyl moiety exhibits higher antioxidant and cytoprotective effects than astragalin. The 6′′-O-p-coumaroyl moiety of tiliroside not only enhances the possibility of electron-transfer and hydrogen-atom-transfer-based multi-pathways, but also enhances the likelihood of Fe-chelating. The p-coumaroylation of the 6"-OH position could therefore be regarded as a potential approach for improving the antioxidant and cytoprotective effects of flavonoid glycosides in MSC implantation therapy.

  19. Synthesis and Bioactivities of Novel Pyrazole Oxime Derivatives Containing a 5-Trifluoromethylpyridyl Moiety

    Directory of Open Access Journals (Sweden)

    Hong Dai

    2016-02-01

    Full Text Available In this study, in order to find novel biologically active pyrazole oxime compounds, a series of pyrazole oxime derivatives containing a 5-trifluoromethylpyridyl moiety were synthesized. Preliminary bioassays indicated that most title compounds were found to display good to excellent acaricidal activity against Tetranychus cinnabarinus at a concentration of 200 μg/mL, and some designed compounds still showed excellent acaricidal activity against Tetranychus cinnabarinus at the concentration of 10 μg/mL, especially since the inhibition rates of compounds 8e, 8f, 8l, 8m, 8n, 8p, and 8q were all 100.00%. Interestingly, some target compounds exhibited moderate to good insecticidal activities against Plutella xylostella and Aphis craccivora at a concentration of 200 μg/mL; furthermore, compounds 8e and 8l possessed outstanding insecticidal activities against Plutella xylostella under the concentration of 50 μg/mL.

  20. Sulforaphane Analogues with Heterocyclic Moieties: Syntheses and Inhibitory Activities against Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Ye-Hui Shi

    2016-04-01

    Full Text Available Recent studies have shown that sulforaphane (SFN selectively inhibits the growth of ALDH+ breast cancer stem-like cells.Herein, a series of SFN analogues were synthesized and evaluated against breast cancer cell lines MCF-7 and SUM-159, and the leukemia stem cell-like cell line KG-1a. These SFN analogues were characterized by the replacement of the methyl group with heterocyclic moieties, and the replacement of the sulfoxide group with sulfide or sulfone. A growth inhibitory assay indicated that the tetrazole analogs 3d, 8d and 9d were significantly more potent than SFN against the three cancer cell lines. Compound 14c, the water soluble derivative of tetrazole sulfide 3d, demonstrated higher potency against KG-1a cell line than 3d. SFN, 3d and 14c significantly induced the activation of caspase-3, and reduced the ALDH+ subpopulation in the SUM159 cell line, while the marketed drug doxrubicin(DOX increased the ALDH+ subpopulation.

  1. Heat Shock Protein-Inducing Property of Diarylheptanoid Containing Chalcone Moiety from Alpinia katsumadai

    Directory of Open Access Journals (Sweden)

    Joo-Won Nam

    2017-10-01

    Full Text Available A new diarylheptanoid containing a chalcone moiety, katsumain H (1, was isolated from the seeds of Alpinia katsumadai. The structure was elucidated using a combination of 1D/2D NMR spectroscopy and mass spectrometry data analysis. The absolute configurations of C-3, C-5, and C-7 in 1 were assigned based on its optical rotation and after comparing its NMR chemical shifts with those of its diastereoisomers, katsumain E and katsumain F, which were previously isolated from this plant and characterized. In this study, the stimulatory effects of compounds 1 and 2 were evaluated on heat shock factor 1 (HSF1, heat shock protein 27 (HSP27, and HSP70. Compounds 1 and 2 increased the expression of HSF1 (1.056- and 1.200-fold, respectively, HSP27 (1.312- and 1.242-fold, respectively, and HSP70 (1.234- and 1.271-fold, respectively, without increased cytotoxicity.

  2. Synthesis, Characterization, and Anti-Inflammatory Activities of Methyl Salicylate Derivatives Bearing Piperazine Moiety.

    Science.gov (United States)

    Li, Jingfen; Yin, Yong; Wang, Lisheng; Liang, Pengyun; Li, Menghua; Liu, Xu; Wu, Lichuan; Yang, Hua

    2016-11-23

    In this study, a new series of 16 methyl salicylate derivatives bearing a piperazine moiety were synthesized and characterized. The in vivo anti-inflammatory activities of target compounds were investigated against xylol-induced ear edema and carrageenan-induced paw edema in mice. The results showed that all synthesized compounds exhibited potent anti-inflammatory activities. Especially, the anti-inflammatory activities of compounds M15 and M16 were higher than that of aspirin and even equal to that of indomethacin at the same dose. In addition, the in vitro cytotoxicity activities and anti-inflammatory activities of four target compounds were performed in RAW264.7 macrophages, and compound M16 was found to significantly inhibit the release of lipopolysaccharide (LPS)-induced interleukin (IL)-6 and tumor necrosis factor (TNF)-α in a dose-dependent manner. In addition, compound M16 was found to attenuate LPS induced cyclooxygenase (COX)-2 up-regulation. The current preliminary study may provide information for the development of new and safe anti-inflammatory agents.

  3. Biomimetic PDMS-hydroxyurethane terminated with catecholic moieties for chemical grafting on transition metal oxide-based surfaces

    Science.gov (United States)

    de Aguiar, Kelen R.; Rischka, Klaus; Gätjen, Linda; Noeske, Paul-Ludwig Michael; Cavalcanti, Welchy Leite; Rodrigues-Filho, Ubirajara P.

    2018-01-01

    The aim of this work was to synthesize a non-isocyanate poly(dimethylsiloxane) hydroxyurethane with biomimetic terminal catechol moieties, as a candidate for inorganic and metallic surface modification. Such surface modifier is capable to strongly attach onto metallic and inorganic substrates forming layers and, in addition, providing water-repellent surfaces. The non-isocyanate route is based on carbon dioxide cycloaddition into bis-epoxide, resulting in a precursor bis(cyclic carbonate)-polydimethylsiloxane (CCPDMS), thus fully replacing isocyanate in the manufacture process. A biomimetic approach was chosen with the molecular composition being inspired by terminal peptides present in adhesive proteins of mussels, like Mefp (Mytilus edulis foot protein), which bear catechol moieties and are strong adhesives even under natural and saline water. The catechol terminal groups were grafted by aminolysis reaction into a polydimethylsiloxane backbone. The product, PDMSUr-Dopamine, presented high affinity towards inhomogeneous alloy surfaces terminated by native oxide layers as demonstrated by quartz crystal microbalance (QCM-D), as well as stability against desorption by rinsing with ethanol. As revealed by QCM-D, X-ray photoelectron spectroscopy (XPS) and computational studies, the thickness and composition of the resulting nanolayers indicated an attachment of PDMSUr-Dopamine molecules to the substrate through both terminal catechol groups, with the adsorbate exposing the hydrophobic PDMS backbone. This hypothesis was investigated by classical molecular dynamic simulation (MD) of pure PDMSUr-Dopamine molecules on SiO2 surfaces. The computationally obtained PDMSUr-Dopamine assembly is in agreement with the conclusions from the experiments regarding the conformation of PDMSUr-Dopamine towards the surface. The tendency of the terminal catechol groups to approach the surface is in agreement with proposed model for the attachment PDMSUr-Dopamine. Remarkably, the versatile

  4. Synthesis and pharmacological characterization of a novel nitric oxide-releasing diclofenac derivative containing a benzofuroxan moiety.

    Science.gov (United States)

    de Carvalho, Paulo Sérgio; Maróstica, Marta; Gambero, Alessandra; Pedrazzoli, José

    2010-06-01

    1-oxy-benzo[1,2,5]oxadiazol-5-ylmethyl [2-(2,6-dichloro-phenylamino)-phenyl]-acetate, a new diclofenac derivative bearing a benzofuroxan heterocyclic moiety in its structure, was prepared by the reaction of sodium diclofenac and 5-bromomethyl-benzo[1,2,5]oxadiazole 1-oxide. Pharmacological characterization of this modified diclofenac maintained the anti-inflammatory activity similar to its parent compound assayed in vitro and in vivo. The ulcerogenic properties of native diclofenac were not observed with this modified compound, despite the inhibition of prostaglandin E2 gastric content. The better gastric tolerability seems to be related to nitric oxide release ability. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

  5. Effect of molecular aggregation on the photo-induced anisotropy in amorphous polymethacrylate bearing an aminonitroazobenzene moiety

    CERN Document Server

    Kim, B J; Choi, D H

    2001-01-01

    We investigated H-type molecular aggregation in a simply spin-coated amorphous homopolymer film of polymethacrylate containing push-pull azobenzene moieties. It was found that the aggregate formation was strongly influenced by thermal treatment and that the aggregate created in the polymer film could be easily disrupted by irradiation of a linearly polarized light. In the first writing cycle of aggregated polymer film, photo-induced birefringence showed a steep increase to the highest value followed by a gradual decrease to the certain asymptotic value under longer irradiation of linearly polarized light. This unique behavior could be attributed to the cooperative motion and the disruption of the aggregated molecules under continuous irradiation of light.

  6. Effect of molecular aggregation on the photo-induced anisotropy in amorphous polymethacrylate bearing an aminonitroazobenzene moiety

    International Nuclear Information System (INIS)

    Kim, Beom Jun; Park, Soo Young; Choi, Dong Hoon

    2001-01-01

    We investigated H-type molecular aggregation in a simply spin-coated amorphous homopolymer film of polymethacrylate containing push-pull azobenzene moieties. It was found that the aggregate formation was strongly influenced by thermal treatment and that the aggregate created in the polymer film could be easily disrupted by irradiation of a linearly polarized light. In the first writing cycle of aggregated polymer film, photo-induced birefringence showed a steep increase to the highest value followed by a gradual decrease to the certain asymptotic value under longer irradiation of linearly polarized light. This unique behavior could be attributed to the cooperative motion and the disruption of the aggregated molecules under continuous irradiation of light

  7. Targeting N-Glycan Cryptic Sugar Moieties for Broad-Spectrum Virus Neutralization: Progress in Identifying Conserved Molecular Targets in Viruses of Distinct Phylogenetic Origins

    Directory of Open Access Journals (Sweden)

    Denong Wang

    2015-03-01

    Full Text Available Identifying molecular targets for eliciting broadly virus-neutralizing antibodies is one of the key steps toward development of vaccines against emerging viral pathogens. Owing to genomic and somatic diversities among viral species, identifying protein targets for broad-spectrum virus neutralization is highly challenging even for the same virus, such as HIV-1. However, viruses rely on host glycosylation machineries to synthesize and express glycans and, thereby, may display common carbohydrate moieties. Thus, exploring glycan-binding profiles of broad-spectrum virus-neutralizing agents may provide key information to uncover the carbohydrate-based virus-neutralizing epitopes. In this study, we characterized two broadly HIV-neutralizing agents, human monoclonal antibody 2G12 and Galanthus nivalis lectin (GNA, for their viral targeting activities. Although these agents were known to be specific for oligomannosyl antigens, they differ strikingly in virus-binding activities. The former is HIV-1 specific; the latter is broadly reactive and is able to neutralize viruses of distinct phylogenetic origins, such as HIV-1, severe acute respiratory syndrome coronavirus (SARS-CoV, and human cytomegalovirus (HCMV. In carbohydrate microarray analyses, we explored the molecular basis underlying the striking differences in the spectrum of anti-virus activities of the two probes. Unlike 2G12, which is strictly specific for the high-density Man9GlcNAc2Asn (Man9-clusters, GNA recognizes a number of N-glycan cryptic sugar moieties. These include not only the known oligomannosyl antigens but also previously unrecognized tri-antennary or multi-valent GlcNAc-terminating N-glycan epitopes (Tri/m-Gn. These findings highlight the potential of N-glycan cryptic sugar moieties as conserved targets for broad-spectrum virus neutralization and suggest the GNA-model of glycan-binding warrants focused investigation.

  8. CYTOCHROME P450 REGULATION: THE INTERPLAY BETWEEN ITS HEME AND APOPROTEIN MOIETIES IN SYNTHESIS, ASSEMBLY, REPAIR AND DISPOSAL123

    OpenAIRE

    Correia, Maria Almira; Sinclair, Peter R.; De Matteis, Francesco

    2010-01-01

    Heme is vital to our aerobic universe. Heme cellular content is finely tuned through an exquisite control of synthesis and degradation. Heme deficiency is deleterious to cells, whereas excess heme is toxic. Most of the cellular heme serves as the prosthetic moiety of functionally diverse hemoproteins, including cytochromes P450 (P450s). In the liver, P450s are its major consumers with >50% of hepatic heme committed to their synthesis. Prosthetic heme is the sine qua non of P450 catalytic biot...

  9. Quantum mechanics study of repulsive π-π interaction and flexibility of phenyl moiety in the iron azodioxide complex

    Science.gov (United States)

    Liu, Yuemin; Liu, Yucheng; Murru, Siva; Tzeng, Nianfeng; Srivastava, Radhey S.

    2015-10-01

    In this study, repulsive π-π interactions within iron azodioxide complex Fe[Ph(O)NN(O)Ph]3 were quantum mechanically characterized using DFT, MP2 and CCSD(T) methods. Flexibility of six phenyl moieties in this complex structure was also investigated by structural optimization approach using the DFT methods. Our MP2 and CCSD(T) calculations of the closest pair provided interaction energy of 6.62 and 8.29 kcal/mol respectively, which indicate a strongest repulsion among these intra-molecular π-π interactions. Interaction energy of the particular π-π pair calculated from 24 hybrid DFT methods ranges from 4.56 kcal/mol from BHandH method to 15.15 kcal/mol from O3LYP method. Cares should be exercised when interpreting interaction energy and geometry optimization from DFT simulation of systems containing π-π interaction. Comparison between the DFT results and the benchmark CCSD(T) results shows that the DFT calculations of π-π interaction are reasonable but still need to be interpreted with caution. Furthermore, MP2 interaction energy of -44.69 kcal/mol between two substituted π systems/phenyl rings Ph(O)N-moieties suggested that above energetically unfavorable π-π interaction can be compensated by the covalent bond N-N in a single ligand Ph(O)NN(O)Ph, which allows for a reasonable stability across the complex molecules. Optimizations of the entire complex molecule using B3LYP and M06HF methods produced a large variation of π-π distances and orientations, which implied that the complex molecule may perform catalysis at room temperature.

  10. Peripheral Hole Acceptor Moieties on an Organic Dye Improve Dye‐Sensitized Solar Cell Performance

    Science.gov (United States)

    Hao, Yan; Gabrielsson, Erik; Lohse, Peter William; Yang, Wenxing; Johansson, Erik M. J.; Hagfeldt, Anders

    2015-01-01

    Investigation of charge transfer dynamics in dye‐sensitized solar cells is of fundamental interest and the control of these dynamics is a key factor for developing more efficient solar cell devices. One possibility for attenuating losses through recombination between injected electrons and oxidized dye molecules is to move the positive charge further away from the metal oxide surface. For this purpose, a metal‐free dye named E6 is developed, in which the chromophore core is tethered to two external triphenylamine (TPA) units. After photoinduced electron injection into TiO2, the remaining hole is rapidly transferred to a peripheral TPA unit. Electron–hole recombination is slowed down by 30% compared to a reference dye without peripheral TPA units. Furthermore, it is found that the added TPA moieties improve the electron blocking effect of the dye, retarding recombination of electrons from TiO2 to the cobalt‐based electrolyte. PMID:27722076

  11. A Carbohydrate Moiety of Secreted Stage-Specific Glycoprotein 4 Participates in Host Cell Invasion by Trypanosoma cruzi Extracellular Amastigotes

    Science.gov (United States)

    Florentino, Pilar T. V.; Real, Fernando; Orikaza, Cristina M.; da Cunha, Julia P. C.; Vitorino, Francisca N. L.; Cordero, Esteban M.; Sobreira, Tiago J. P.; Mortara, Renato A.

    2018-01-01

    Trypanosoma cruzi is the etiologic agent of Chagas’ disease. It is known that amastigotes derived from trypomastigotes in the extracellular milieu are infective in vitro and in vivo. Extracellular amastigotes (EAs) have a stage-specific surface antigen called Ssp-4, a GPI-anchored glycoprotein that is secreted by the parasites. By immunoprecipitation with the Ssp-4-specific monoclonal antibodies (mAb) 2C2 and 1D9, we isolated the glycoprotein from EAs. By mass spectrometry, we identified the core protein of Ssp-4 and evaluated mRNA expression and the presence of Ssp-4 carbohydrate epitopes recognized by mAb1D9. We demonstrated that the carbohydrate epitope recognized by mAb1D9 could promote host cell invasion by EAs. Although infectious EAs express lower amounts of Ssp-4 compared with less-infectious EAs (at the mRNA and protein levels), it is the glycosylation of Ssp-4 (identified by mAb1D9 staining only in infectious strains and recognized by galectin-3 on host cells) that is the determinant of EA invasion of host cells. Furthermore, Ssp-4 is secreted by EAs, either free or associated with parasite vesicles, and can participate in host-cell interactions. The results presented here describe the possible role of a carbohydrate moiety of T. cruzi surface glycoproteins in host cell invasion by EA forms, highlighting the potential of these moieties as therapeutic and vaccine targets for the treatment of Chagas’ disease. PMID:29692765

  12. Synthesis and characterization of a new class of glycosylated porphyrins bearing the RGD moiety and their application in photodynamic therapy

    International Nuclear Information System (INIS)

    Chaleix, Vincent

    2003-01-01

    The use of porphyrins and analogues as photosensitisers together with visible light is a new treatment of tumors (photodynamic therapy, PDT). Carbohydrate-substituted porphyrins are in this domain very promising compounds. In addition, it is known that endothelial cells of the neo-vascularisation in tumors express αVβ3 integrin. Extracellular domains of this transmembrane glycoprotein are able to bind components of the extracellular matrix (ECM) and more precisely the sequence Arg-Gly-Asp. With the aim of their utilization in photodynamic therapy of cancers, we describe the synthesis and characterization (UV-Visible, mass, NMR) of new glucosylated porphyrins bearing the RGD moiety. The first synthesised compounds were derived from tritolyl and tri-glucosyl-aryl-porphyrins where the peptidic moiety is linked to the phenyl group by a spacer arm by means of a solid phase reaction.. The second series consists of glucosylated porphyrin derivatives bearing a cyclical unsaturated pentapeptide including RGD sequence, obtained by ring closing metathesis in solid phase. We have also synthesized a dimer in which the two glucosylated porphyrins are linked by the RGD sequence. These compounds produced 1 O 2 and photo-cyto-toxicities against K562 leukemia cell line were favourably compared to Photofrin II R . Due to their sensitising abilities, these compounds are of considerable interest for photodynamic therapy. (author) [fr

  13. Synthesis and electroluminescent properties of anthracene derivatives containing electron-withdrawing oxide moieties

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jhin-yeong; Na, Eun Jae; Park, Soo Na [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of); Lee, Seok Jae [Department of Information Display, Hongik University, Seoul, 121-791 (Korea, Republic of); Kim, Young Kwan, E-mail: kimyk@wow.hongik.ac.kr [Department of Information Display, Hongik University, Seoul, 121-791 (Korea, Republic of); Yoon, Seung Soo, E-mail: ssyoon@skku.edu [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of)

    2014-10-15

    Highlights: • Blue fluorescent material is important for application in full-color displays. • We have synthesized emitters based on anthracene connected with oxide moieties. • 1C shows a highly efficient blue EL emission due to electron-injection property. - Abstract: A series of new blue-emitting materials: (4-(10-(naphthalen-2-yl)anthracen-9-yl)phenyl)(phenyl)methanone (1); 9-(naphthalen-2-yl)-10-(4-((diphenyl)phosphine oxide)phenyl)anthracene (2); 9-(naphthalen-2-yl)-10-(4-(phenylsulfonyl)phenyl)anthracene (3) were designed and synthesized via Suzuki cross-coupling reaction. Multilayer OLEDs were fabricated in the following sequence: ITO (180 nm)/NPB (50 nm)/blue materials 1–3 (30 nm)/TPBi (15 nm)/Liq (2 nm)/Al (100 nm). All devices showed the efficient blue EL emissions. In particular, the device using 1 as an emitter exhibited efficient blue electroluminescent properties with a maximum luminous, power, external quantum efficiency and CIE coordinates of 0.36 cd/A, 0.90 lm/W, 0.55% at 20 mA/cm{sup 2} and (x = 0.16, y = 0.20) at 10.0 V, respectively.

  14. Coumarin derivatives bearing benzoheterocycle moiety: synthesis, cholinesterase inhibitory, and docking simulation study

    Directory of Open Access Journals (Sweden)

    Kimia Hirbod

    2017-06-01

    Full Text Available Objective(s: To investigate the efficiency of a novel series of coumarin derivatives bearing benzoheterocycle moiety as novel cholinesterase inhibitors. Materials and Methods: Different 7-hydroxycoumarin derivatives were synthesized via Pechmann or Knoevenagel condensation and conjugated to different benzoheterocycle (8-hydroxyquinoline, 2-mercaptobenzoxazole or 2-mercaptobenzimidazole using dibromoalkanes 3a-m. Final compounds were evaluated against acetylcholinesterase (AChE and butyrylcholinesterase (BuChE by Ellman's method. Kinetic study of AChE inhibition and ligand-protein docking simulation were also carried out for the most potent compound 3b. Results: Some of the compounds revealed potent and selective activity against AChE. Compound 3b containing the quinoline group showed the best activity with an IC50 value of 8.80 µM against AChE. Kinetic study of AChE inhibition revealed the mixed-type inhibition of the enzyme by compound 3b. Ligand-protein docking simulation also showed that the flexibility of the hydrophobic five carbons linker allows the quinoline ring to form π-π interaction with Trp279 in the PAS. Conclusion: We suggest these synthesized compounds could become potential leads for AChE inhibition and prevention of AD symptoms.

  15. Discovery of novel scaffolds for γ-secretase modulators without an arylimidazole moiety.

    Science.gov (United States)

    Sekioka, Ryuichi; Honjo, Eriko; Honda, Shugo; Fuji, Hideyoshi; Akashiba, Hiroki; Mitani, Yasuyuki; Yamasaki, Shingo

    2018-01-15

    Gamma-secretase modulators (GSMs) selectively inhibit the production of amyloid-β 42 (Aβ42) and may therefore be useful in the management of Alzheimer's disease. Most heterocyclic GSMs that are not derived from nonsteroidal anti-inflammatory drugs contain an arylimidazole moiety that potentially inhibits cytochrome P450 (CYP) activity. Here, we discovered imidazopyridine derivatives that represent a new class of scaffold for GSMs, which do not have a strongly basic end group such as arylimidazole. High-throughput screening identified 2-methyl-8-[(2-methylbenzyl)oxy]-3-(pyridin-4-yl)imidazo[1,2-a]pyridine (3a), which inhibited the cellular production of Aβ42 (IC 50  = 7.1 µM) without changing total production of Aβ. Structural optimization of this series of compounds identified 5-[8-(benzyloxy)-2-methylimidazo[1,2-a]pyridin-3-yl]-2-ethylisoindolin-1-one (3m) as a potent inhibitor of Aβ42 (IC 50  = 0.39 µM) but not CYP3A4. Further, 3m demonstrated a sustained pharmacokinetic profile in mice and sufficiently penetrated the brain. Copyright © 2017. Published by Elsevier Ltd.

  16. The design and synthesis of novel SGLT2 inhibitors: C-glycosides with benzyltriazolopyridinone and phenylhydantoin as the aglycone moieties.

    Science.gov (United States)

    Guo, Cheng; Hu, Min; DeOrazio, Russell J; Usyatinsky, Alexander; Fitzpatrick, Kevin; Zhang, Zhenjun; Maeng, Jun-Ho; Kitchen, Douglas B; Tom, Susan; Luche, Michele; Khmelnitsky, Yuri; Mhyre, Andrew J; Guzzo, Peter R; Liu, Shuang

    2014-07-01

    The sodium glucose co-transporter 2 (SGLT2) has received considerable attention in recent years as a target for the treatment of type 2 diabetes mellitus. This report describes the design, synthesis and structure-activity relationship (SAR) of C-glycosides with benzyltriazolopyridinone and phenylhydantoin as the aglycone moieties as novel SGLT2 inhibitors. Compounds 5p and 33b demonstrated high potency in inhibiting SGLT2 and high selectivity against SGLT1. The in vitro ADMET properties of these compounds will also be discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Synthesis of some new heterocyclic compounds bearing a sulfonamide moiety and studying their combined anticancer effect with γ-radiation

    International Nuclear Information System (INIS)

    El-Hossary, E.M.M.

    2010-01-01

    In search for new cytotoxic agents with improved anticancer profile, some new halogen-containing quinoline and pyrimido[4,5-b]quinoline derivatives bearing a free sulfonamide moiety were synthesized. All the newly synthesized target compounds were subjected to in vitro anticancer screening against human breast cancer cell line (MCF7). The most potent compounds, as concluded from the in vitro anticancer screening, were selected to be evaluated again for their in vitro anticancer activity in combination with radiation. Also, the newly synthesized compounds were docked in the active site of the carbonic anhydrase enzyme

  18. Theoretical pKa prediction of the α-phosphate moiety of uridine 5‧-diphosphate-GlcNAc

    Science.gov (United States)

    Vipperla, Bhavaniprasad; Griffiths, Thomas M.; Wang, Xingyong; Yu, Haibo

    2017-01-01

    The pKa value of the α-phosphate moiety of uridine 5‧-diphosphate-GlcNAc (UDP-GlcNAc) has been successfully calculated using density functional theory methods in conjunction with the Polarizable Continuum Models. Theoretical methods were benchmarked over a dataset comprising of alkyl phosphates. B3LYP/6-31+G(d,p) calculations using SMD solvation model provide excellent agreement with the experimental data. The predicted pKa for UDP-GlcNAc is consistent with most recent NMR studies but much higher than what it has long been thought to be. The importance of this study is evident that the predicted pKa for UDP-GlcNAc supports its potential role as a catalytic base in the substrate-assisted biocatalysis.

  19. Renal pelvis urothelial carcinoma of the upper moiety in complete right renal duplex: a case report.

    Science.gov (United States)

    Zhang, Yiran; Yu, Quanfeng; Zhang, Zhihong; Liu, Ranlu; Xu, Yong

    2015-01-01

    Urothelial carcinoma (UC) originated from renal pelvis is the common tumor of the urinary system, however, neoplasia of the renal pelvis in duplex kidneys is extremely rare, especially in the complete renal and ureteral duplex cases. We present the first case of renal pelvis UC of the upper moiety in a complete right renal duplex. This male patient has bilateral complete renal and ureteral duplex. To the best of our knowledge, this is the first reported case of renal pelvis UC in a complete renal duplex system. After this experience we feel that the diagnosis of renal pelvis UC in duplex kidneys is not so easy, and once the diagnosis is determined, the whole renal duplex units and bladder cuff or ectopic orifice should be excised radically.

  20. Radioactive methionine: determination, and distribution of radioactivity in the sulfur, methyl and 4-carbon moieties

    International Nuclear Information System (INIS)

    Giovanelli, J.; Mudd, S.H.

    1985-01-01

    A simple and inexpensive method is described for isolation and determination of [ 14 C]methionine in the non-protein fraction of tissues extensively labeled with 14 C. The effectiveness of the method was demonstrated by isolation of non-protein [ 14 C]methionine (as the carboxymethylsulfonium salt) of proven radiopurity from the plant Lemna which had been grown for a number of generations on (U- 14 C]sucrose and contained a 2000-fold excess of 14 C in undefined non-protein compounds. An advantage is that the isolated methioninecarboxymethlysulfonium salt is readily degraded to permit separate determination of radioactivity in the 4-carbon, methyl and sulfur moieties of methionine. During this work, a facile labilization of 3 H attached to the (carboxy)methylene carbon of methioninecarboxymethylsulfonium salt was observed. This labilization is ascribed to formation of a sulfur ylid. (Auth.)

  1. A Carbohydrate Moiety of Secreted Stage-Specific Glycoprotein 4 Participates in Host Cell Invasion by Trypanosoma cruzi Extracellular Amastigotes

    Directory of Open Access Journals (Sweden)

    Pilar T. V. Florentino

    2018-04-01

    Full Text Available Trypanosoma cruzi is the etiologic agent of Chagas’ disease. It is known that amastigotes derived from trypomastigotes in the extracellular milieu are infective in vitro and in vivo. Extracellular amastigotes (EAs have a stage-specific surface antigen called Ssp-4, a GPI-anchored glycoprotein that is secreted by the parasites. By immunoprecipitation with the Ssp-4-specific monoclonal antibodies (mAb 2C2 and 1D9, we isolated the glycoprotein from EAs. By mass spectrometry, we identified the core protein of Ssp-4 and evaluated mRNA expression and the presence of Ssp-4 carbohydrate epitopes recognized by mAb1D9. We demonstrated that the carbohydrate epitope recognized by mAb1D9 could promote host cell invasion by EAs. Although infectious EAs express lower amounts of Ssp-4 compared with less-infectious EAs (at the mRNA and protein levels, it is the glycosylation of Ssp-4 (identified by mAb1D9 staining only in infectious strains and recognized by galectin-3 on host cells that is the determinant of EA invasion of host cells. Furthermore, Ssp-4 is secreted by EAs, either free or associated with parasite vesicles, and can participate in host-cell interactions. The results presented here describe the possible role of a carbohydrate moiety of T. cruzi surface glycoproteins in host cell invasion by EA forms, highlighting the potential of these moieties as therapeutic and vaccine targets for the treatment of Chagas’ disease.

  2. Preparation and characterization of new polyamide/montmorillonite nanocomposites containing azo moiety in the main chain

    Directory of Open Access Journals (Sweden)

    Khalil Faghihi

    2016-11-01

    Full Text Available Two new samples of polyamide/montmorillonite reinforced nanocomposites containing 4,4′-azobenzoic acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Polyamide (PA 4 as a source of polymer matrix was synthesized by the direct polycondensation reaction of 4,4′-azobenzoic acid 2 with 4,4′-diamino diphenyl ether 3 in the presence of triphenyl phosphite (TPP, CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP. Morphology and structure of the resulting PA-nanocomposite films 4a and 4b with 10 and 20% silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM. The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV–vis spectroscopy, thermogravimetric analysis (TGA and water uptake measurements.

  3. SAR studies directed toward the pyridine moiety of the sap-feeding insecticide sulfoxaflor (Isoclast™ active).

    Science.gov (United States)

    Loso, Michael R; Benko, Zoltan; Buysse, Ann; Johnson, Timothy C; Nugent, Benjamin M; Rogers, Richard B; Sparks, Thomas C; Wang, Nick X; Watson, Gerald B; Zhu, Yuanming

    2016-02-01

    Sap-feeding insect pests constitute a major insect pest complex that includes a range of aphids, whiteflies, planthoppers and other insect species. Sulfoxaflor (Isoclast™ active), a new sulfoximine class insecticide, targets sap-feeding insect pests including those resistant to many other classes of insecticides. A structure activity relationship (SAR) investigation of the sulfoximine insecticides revealed the importance of a 3-pyridyl ring and a methyl substituent on the methylene bridge linking the pyridine and the sulfoximine moiety to achieving strong Myzus persicae activity. A more in depth QSAR investigation of pyridine ring substituents revealed a strong correlation with the calculated logoctanol/water partition coefficient (SlogP). Model development resulted in a highly predictive model for a set of 18 sulfoximines including sulfoxaflor. The model is consistent with and helps explain the highly optimized pyridine substitution pattern for sulfoxaflor. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Online feature selection with streaming features.

    Science.gov (United States)

    Wu, Xindong; Yu, Kui; Ding, Wei; Wang, Hao; Zhu, Xingquan

    2013-05-01

    We propose a new online feature selection framework for applications with streaming features where the knowledge of the full feature space is unknown in advance. We define streaming features as features that flow in one by one over time whereas the number of training examples remains fixed. This is in contrast with traditional online learning methods that only deal with sequentially added observations, with little attention being paid to streaming features. The critical challenges for Online Streaming Feature Selection (OSFS) include 1) the continuous growth of feature volumes over time, 2) a large feature space, possibly of unknown or infinite size, and 3) the unavailability of the entire feature set before learning starts. In the paper, we present a novel Online Streaming Feature Selection method to select strongly relevant and nonredundant features on the fly. An efficient Fast-OSFS algorithm is proposed to improve feature selection performance. The proposed algorithms are evaluated extensively on high-dimensional datasets and also with a real-world case study on impact crater detection. Experimental results demonstrate that the algorithms achieve better compactness and higher prediction accuracy than existing streaming feature selection algorithms.

  5. Understanding Legacy Features with Featureous

    DEFF Research Database (Denmark)

    Olszak, Andrzej; Jørgensen, Bo Nørregaard

    2011-01-01

    Java programs called Featureous that addresses this issue. Featureous allows a programmer to easily establish feature-code traceability links and to analyze their characteristics using a number of visualizations. Featureous is an extension to the NetBeans IDE, and can itself be extended by third...

  6. Investigating the use of endogenous quinoid moieties on carbon fibre as means of developing micro pH sensors

    International Nuclear Information System (INIS)

    Anderson, Ashleigh; Phair, Jolene; Benson, John; Meenan, Brian; Davis, James

    2014-01-01

    The redox profile obtained from electrochemically oxidised carbon fibre was exploited as a foundation from which to design a reusable pH probe. X-ray photoelectron spectroscopy of the surface after anodisation revealed an increase in the population of endogenous quinone moieties. Square wave voltammograms recorded in various buffer solutions (pH 3–9) yielded a distinct and unambiguous oxidation process through which to ascribe the peak potential — with the latter found to shift in a sub-Nernstian (− 0.052 V/pH) manner. The design of a discrete 2-electrode reusable probe which provides a rapid assessment of pH is described and a preliminary characterisation of the electrochemical performance is critically assessed. - Graphical abstract: The redox profile obtained from electrochemically oxidised carbon fibre was exploited as a foundation from which to design a reusable pH probe. X-ray photoelectron spectroscopy of the surface after anodisation revealed an increase in the population endogenous quinone moieties. Square wave voltammograms recorded in various buffer solutions (pH 3–9) yielded a distinct and unambiguous oxidation process through which to ascribe the peak potential — with the latter found to shift in a sub-Nernstian (− 0.052 V/pH) manner. The design of a discrete 2-electrode reusable probe which provides a rapid assessment of pH is described and a preliminary characterisation of the electrochemical performance is critically assessed. - Highlights: • In situ creation of pH sensitive quinone groups on carbon fibre • Versatile and accessible approach to manufacturing disposable pH sensors • Miniature probe design enables monitoring pH in small volumes. • Detailed surface characterisation of electrochemically modified carbon fibre

  7. Investigating the use of endogenous quinoid moieties on carbon fibre as means of developing micro pH sensors

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Ashleigh; Phair, Jolene; Benson, John; Meenan, Brian; Davis, James, E-mail: james.davis@ulster.ac.uk

    2014-10-01

    The redox profile obtained from electrochemically oxidised carbon fibre was exploited as a foundation from which to design a reusable pH probe. X-ray photoelectron spectroscopy of the surface after anodisation revealed an increase in the population of endogenous quinone moieties. Square wave voltammograms recorded in various buffer solutions (pH 3–9) yielded a distinct and unambiguous oxidation process through which to ascribe the peak potential — with the latter found to shift in a sub-Nernstian (− 0.052 V/pH) manner. The design of a discrete 2-electrode reusable probe which provides a rapid assessment of pH is described and a preliminary characterisation of the electrochemical performance is critically assessed. - Graphical abstract: The redox profile obtained from electrochemically oxidised carbon fibre was exploited as a foundation from which to design a reusable pH probe. X-ray photoelectron spectroscopy of the surface after anodisation revealed an increase in the population endogenous quinone moieties. Square wave voltammograms recorded in various buffer solutions (pH 3–9) yielded a distinct and unambiguous oxidation process through which to ascribe the peak potential — with the latter found to shift in a sub-Nernstian (− 0.052 V/pH) manner. The design of a discrete 2-electrode reusable probe which provides a rapid assessment of pH is described and a preliminary characterisation of the electrochemical performance is critically assessed. - Highlights: • In situ creation of pH sensitive quinone groups on carbon fibre • Versatile and accessible approach to manufacturing disposable pH sensors • Miniature probe design enables monitoring pH in small volumes. • Detailed surface characterisation of electrochemically modified carbon fibre.

  8. A New Flame-Retardant Polyamide Containing Phosphine Oxide and N,N-(4,4-diphenylether) Moieties in the Main Chain: Synthesis and Characterization

    OpenAIRE

    FAGHIHI, Khalil

    2014-01-01

    A new flame-retardant polyamide containing phosphine oxide moieties in the main chain was synthesized from the solution polycondensation reaction of bis(3-aminophenyl) phenyl phosphine oxide with N,N-(4,4-diphenylether) bis trimellitimide, using thionyl chloride, N-methyl-2-pyrolidone, and pyridine as condensing agents. This new polymer was obtained in high yield (92%), has high inherent viscosity (0.73 dL/g), and was characterized by elemental analysis, FT-IR spectroscopy, thermal gr...

  9. Comparative Studies on Conventional and Ultrasound-Assisted Synthesis of Novel Homoallylic Alcohol Derivatives Linked to Sulfonyl Dibenzene Moiety in Aqueous Media

    Directory of Open Access Journals (Sweden)

    Mohamed F. Mady

    2013-01-01

    Full Text Available Novel homoallylic alcohols incorporating sulfone moieties were synthesized by the treatment of different carbonyl compounds with allylic bromides in aqueous media via sonochemical Barbier-type reaction conditions. Sulfonation of α-bromoketones with sodium benzenesulfinate in presence of CuI/2,6-lutidine rapidly gave β-keto-sulfones in good yields. In general, ultrasound irradiation offered the advantages of high yields, short reaction times, and simplicity compared to the conventional methods. The structures of all the compounds were confirmed by analytical and spectral data.

  10. Cytochrome P450 regulation: the interplay between its heme and apoprotein moieties in synthesis, assembly, repair, and disposal.

    Science.gov (United States)

    Correia, Maria Almira; Sinclair, Peter R; De Matteis, Francesco

    2011-02-01

    Heme is vital to our aerobic universe. Heme cellular content is finely tuned through an exquisite control of synthesis and degradation. Heme deficiency is deleterious to cells, whereas excess heme is toxic. Most of the cellular heme serves as the prosthetic moiety of functionally diverse hemoproteins, including cytochromes P450 (P450s). In the liver, P450s are its major consumers, with >50% of hepatic heme committed to their synthesis. Prosthetic heme is the sine qua non of P450 catalytic biotransformation of both endo- and xenobiotics. This well-recognized functional role notwithstanding, heme also regulates P450 protein synthesis, assembly, repair, and disposal. These less well-appreciated aspects are reviewed herein.

  11. Computer Based Design and Synthesis of Some Novel Thiazole Derivatives Bearing a Sulfonamide Moiety and Studying Their Potential Synergistic Anticancer Effect With γ-Irradiation

    International Nuclear Information System (INIS)

    Soliman, A.M.M.

    2011-01-01

    In a search for new cytotoxic agents with improved antitumor activity and selectivity, some new thiazole, thiazolo pyrimidine, thiazolo pyrane and thiazolo pyrano pyrimidine derivatives bearing sulfonamide moiety were synthesized. The newly synthesized compounds were evaluated for their antitumor activity alone and in combination with γ-irradiation. These new compounds were docked inside the active site of carbonic anhydrase II to predict their mechanism of action.

  12. Synthesis, characterization and theoretical study of a new asymmetrical tripodal amine containing morpholine moiety

    Directory of Open Access Journals (Sweden)

    Majid Rezaeivala

    2016-11-01

    Full Text Available A new asymmetrical tripodal amine, [H3L2]Br3 containing morpholine moiety was prepared from reacting of one equivalent of N-(3-aminopropylmorpholine and two equivalents of tosylaziridine, followed by detosylation with HBr/CH3COOH. The products were characterized by various spectroscopic methods such as FAB-MS, elemental analysis, 1H and 13C NMR spectroscopy. The crystal structure of the hydrobromide salt of the latter amine, [H3L2]Br3, was also determined. For triprotonated form of the ligand L2 we can consider several microspecies and/or conformers. A theoretical study at B3LYP/6-31G∗∗ level of theory showed that the characterized microspecies is the most stable microspecies for the triprotonated form of the ligand. It was shown that the experimental NMR data for [H3L2]Br3 in solution have good correlation with the corresponding calculated data for the most stable microspecies of [H3L2]3+ in the gas phase.

  13. Novel α,β-unsaturated amide derivatives bearing α-amino phosphonate moiety as potential antiviral agents.

    Science.gov (United States)

    Lan, Xianmin; Xie, Dandan; Yin, Limin; Wang, Zhenzhen; Chen, Jin; Zhang, Awei; Song, Baoan; Hu, Deyu

    2017-09-15

    Based on flexible construction and broad bioactivity of ferulic acid, a series of novel α,β-unsaturated amide derivatives bearing α-aminophosphonate moiety were designed, synthesized and systematically evaluated for their antiviral activity. Bioassay results indicated that some compounds exhibited good antiviral activities against cucumber mosaic virus (CMV) and tobacco mosaic virus (TMV) in vivo. Especially, compound g18 showed excellent curative and protective activities against CMV, with half-maximal effective concentration (EC 50 ) values of 284.67μg/mL and 216.30μg/mL, which were obviously superior to that of Ningnanmycin (352.08μg/mL and 262.53μg/mL). Preliminary structure-activity relationships (SARs) analysis revealed that the introduction of electron-withdrawing group at the 2-position or 4-position of the aromatic ring is favorable for antiviral activity. Present work provides a promising template for development of potential inhibitor of plant virus. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Ultrasound-aided formation of gold nanoparticles on multi-walled carbon nanotubes functionalized with mercaptobenzene moieties.

    Science.gov (United States)

    Park, Gle; Lee, Kyung G; Lee, Seok Jae; Park, Tae Jung; Wi, Ringbok; Wang, Kye Won; Kim, Do Hyun

    2011-07-01

    A hybrid of multi-walled carbon nanotube (MWCNT) and gold nanoparticle (Au NP) was prepared under ultrasound irradiation. The approach starts with the functionalization of the walls of MWCNTs with mercaptobenzene moieties for the subsequent immobilization of Au NPs. From the Raman spectra, mercaptobenzene was proven to exist on the MWCNTs. Gold ions were added to the aqueous dispersion of functionalized MWCNTs (f-MWCNTs), and were reduced with the aid of ultrasound and ammonium hydroxide. The reduced gold nanoparticles were examined from the TEM images. Au NPs adhered specifically on the thiol groups of mercaptobenzene to be deposited uniformly on the outer walls of the f-MWCNTs. The application of ultrasound led to a high yield of MWCNT-Au nanocomposites and to the dense distribution of the Au NPs. Moreover, the synthesis reaction rate of the hybrid was considerably enhanced relative to synthesis with mechanical agitation. Through an adsorption test using gold-binding-peptide-(GBP)-modified biomolecules, the hybrid's potential for biological diagnosis was verified.

  15. Synthesis of Hydrophilic Sulfur-Containing Adsorbents for Noble Metals Having Thiocarbonyl Group Based on a Methacrylate Bearing Dithiocarbonate Moieties

    Directory of Open Access Journals (Sweden)

    Haruki Kinemuchi

    2018-01-01

    Full Text Available Novel hydrophilic sulfur-containing adsorbents for noble metals were prepared by the radical terpolymerization of a methacrylate bearing dithiocarbonate moieties (DTCMMA, hydrophilic monomers, and a cross-linker. The resulting adsorbents efficiently and selectively adsorbed noble metals (Au, Ag, and Pd from various multielement aqueous solutions at room temperature owing to the thiocarbonyl group having high affinity toward noble metals. The metal adsorption by the adsorbents was proceeded by simple mixing followed by filtration. The noble metal selectivity of the adsorbent obtained from DTCMMA and N-isopropylacrylamide was higher than that of the adsorbent obtained from DTCMMA and N,N-dimethylacrylamide due to the lower nonspecific adsorption.

  16. Tyrosine B10 triggers a heme propionate hydrogen bonding network loop with glutamine E7 moiety

    International Nuclear Information System (INIS)

    Ramos-Santana, Brenda J.; López-Garriga, Juan

    2012-01-01

    Highlights: ► H-bonding network loop by PheB10Tyr mutation is proposed. ► The propionate group H-bonding network restricted the flexibility of the heme. ► The hydrogen bonding interaction modulates the electron density of the iron. ► Propionate H-bonding network loop explains the heme-ligand stabilization. -- Abstract: Propionates, as peripheral groups of the heme active center in hemeproteins have been described to contribute in the modulation of heme reactivity and ligand selection. These electronic characteristics prompted the question of whether the presence of hydrogen bonding networks between propionates and distal amino acids present in the heme ligand moiety can modulate physiological relevant events, like ligand binding association and dissociation activities. Here, the role of these networks was evaluated by NMR spectroscopy using the hemoglobin I PheB10Tyr mutant from Lucina pectinata as model for TyrB10 and GlnE7 hemeproteins. 1 H-NMR results for the rHbICN PheB10Tyr derivative showed chemical shifts of TyrB10 OHη at 31.00 ppm, GlnE7 N ε1 H/N ε2 H at 10.66 ppm/−3.27 ppm, and PheE11 C δ H at 11.75 ppm, indicating the presence of a crowded, collapsed, and constrained distal pocket. Strong dipolar contacts and inter-residues crosspeaks between GlnE7/6-propionate group, GlnE7/TyrB10 and TyrB10/CN suggest that this hydrogen bonding network loop between GlnE7, TyrB10, 6-propionate group, and the heme ligand contribute significantly to the modulation of the heme iron electron density as well as the ligand stabilization mechanism. Therefore, the network loop presented here support the fact that the electron withdrawing character of the hydrogen bonding is controlled by the interaction of the propionates and the nearby electronic environments contributing to the modulation of the heme electron density state. Thus, we hypothesize that in hemeproteins with similar electrostatic environment the flexibility of the heme-6-propionate promotes a hydrogen

  17. Insights into the structure-activity relationship of the anticancer compound ZJ-101, a derivative of marine natural product superstolide A: A critical role played by the conjugated trienyl lactone moiety.

    Science.gov (United States)

    Qian, Shan; Shah, Aashay K; Head, Sarah A; Liu, Jun O; Jin, Zhendong

    2016-08-01

    Compound ZJ-101, a structurally simplified analog of the marine natural product superstolide A, was previously developed in our laboratory. In the subsequent structure-activity relationship study, two new analogs, ZJ-105 and ZJ-106, were designed and synthesized to probe the importance of the conjugated trienyl lactone moiety of the molecule by replacing the C2-C3 double bond in ZJ-101 with a single bond and switching the geometry of the C4-C5 double bond in ZJ-101 from Z to E, respectively. Biological evaluation showed that ZJ-105 completely loses antiproliferative activity whereas ZJ-106 is significantly less active against cancer cells in vitro than ZJ-101, suggesting that the conjugated trienyl lactone moiety of the molecule is critical for its anticancer activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Discovery of a low-systemic-exposure DGAT-1 inhibitor with a picolinoylpyrrolidine-2-carboxylic acid moiety.

    Science.gov (United States)

    Yan, Jianwei; Wang, Gaihong; Dang, Xiangyu; Guo, Binbin; Chen, Wuhong; Wang, Ting; Zeng, Limin; Wang, Heyao; Hu, Youhong

    2017-09-01

    A series of diacylglycerol O-acyltransferase 1 (DGAT-1) inhibitors with a picolinoylpyrrolidine-2-carboxylic acid moiety were designed and synthesized. Of these compounds, compound 22 exhibited excellent DGAT-1-inhibitory activity (hDGAT-1 enzyme assay, 50% inhibitory concentration [IC 50 ]=3.5±0.9nM) and effectively reduced the intracellular triglyceride contents in 3T3-L1, HepG2 and Caco-2 cells. A preliminary study of the plasma and tissue distributions of compound 22 in mice revealed low plasma exposure and high concentrations in different segments of the intestine and liver, which may facilitate targeting DGAT-1. Furthermore, in an acute lipid challenge test, compound 22 showed a dose-dependent inhibitory effect on high-serum triglycerides in C57/KSJ mice induced by olive oil (1, 3, and 10mg/kg, i.g.). Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Thermal and Optical Properties of New Poly(amide-imide)/Nanocomposite Reinforced by Layer Silicate Containing Diphenyl Ether Moieties

    Science.gov (United States)

    Faghihi, Khalil; Faramarzi, Ellahe; Shabanian, Meisam

    2011-04-01

    New poly(amide-imide)-montmorillonite reinforced nanocomposites containing Bis(4-N-trimellitylimido) diphenyl ether moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 4 was synthesized by the direct polycondensation reaction of Bis(4-N-trimellitylimido) diphenyl ether 3 with 4,4'-diamino diphenyl ether 2 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films 4a and 4b with 10 and 20 mass% silicate particles respectively, were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The properties of nanocomposites films were investigated by using Uv-vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements.

  20. Design, Synthesis and Biological Evaluation of Novel Bromophenol Derivatives Incorporating Indolin-2-One Moiety as Potential Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Li-Jun Wang

    2015-02-01

    Full Text Available A series of bromophenol derivatives containing indolin-2-one moiety were designed and evaluated that for their anticancer activities against A549, Bel7402, HepG2, HeLa and HCT116 cancer cell lines using MTT assay in vitro. Among them, seven compounds (4g–4i, 5h, 6d, 7a, 7b showed potent activity against the tested five human cancer cell lines. Wound-healing assay demonstrated that compound 4g can be used as a potent compound for inactivating invasion and metastasis by inhibiting the migration of cancer cells. The structure–activity relationships (SARs of bromophenol derivatives had been discussed, which were useful for exploring and developing bromophenol derivatives as novel anticancer drugs.

  1. Effect of pendant isophthalic acid moieties on the adsorption properties of light hydrocarbons in HKUST-1-like tbo -MOFs: Application to methane purification and storage

    KAUST Repository

    Belmabkhout, Youssef

    2014-01-01

    Equilibrium adsorption of methane (CH4), C2+ gases (ethane (C2H6), ethylene (C2H4), propane (C3H8), and propylene (C3H6)), and carbon dioxide (CO2) was measured on a series of tbo-MOFs (topological analogues of the prototypical MOF, HKUST-1, correspondingly dubbed tbo-MOF-1), which were developed via the supermolecular building layer (SBL) pillaring strategy. Specifically, tbo-MOF-2 and its isoreticular, functionalized analogue, tbo-MOF-2-{CH2O[Ph(CO2H)2]}2 (or tbo-MOF-3), which is characterized by pendant isophthalic acid moieties freely pointing into the cavities, were evaluated on the basis of potential use in methane storage and C2+/CH4 separation. The parent, tbo-MOF-2, showed high gravimetric and volumetric CH4 uptake, close to the U.S. Department of Energy (DOE) target for methane storage at 35 bar and room temperature. Though the presence of the pendant isophthalic acid moiety in the analogous compound, tbo-MOF-3, led to a decrease in total CH4 uptake, due mainly to the reduced size of the cavities, interestingly, it increased the affinity of the SBL-based tbo-MOF platform for propane, propene, ethane, and ethylene at low pressures compared with CH4, due additionally to the enhanced interactions of the highly polarizable light hydrocarbons with the isophthalic acid moiety. Using Ideal Adsorption Solution Theory (IAST), the predicted mixture adsorption equilibria for the C3H8/CH4, C3H6/CH4, C2H6/CH4, C2H4/CH4, and C3H8/CO2 systems showed high adsorption selectivity for C2+ over methane for tbo-MOF-3 compared with tbo-MOF-2. The high working storage capacity of tbo-MOF-2 and the high affinity of tbo-MOF-3 for C2+ over CH4 and CO2 make tbo-MOF an ideal platform for studies in gas storage and separation.

  2. Synthesis and characterisation of sulphonated poly(arylene sulphone) terpolymers with triphenylphosphine oxide moieties for proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Titvinidze, G.; Kaltbeitzel, A.; Manhart, A.; Meyer, W.H. [Max Planck Institute for Polymer Research, Mainz (Germany)

    2010-06-15

    For application in fuel cells, a series of sulphonated poly(phenylene sulphone) terpolymers with triphenylphosphine oxide moieties as constitutional units in the polymer backbone have been prepared. The synthesis of the terpolymers represents a two-step process including: (i) an aromatic nucleophilic substitution polycondensation of three difluoro monomers with varying ratios, i.e. 3,3'-disulphonate-4,4'-difluorodiphenylsulphone, 4,4'-difluorodiphenylsulphone and bis(4-fluorophenyl)phenyl phosphine oxide (BFPPO), with 4,4'-thiobisbenzenethiol yielding sulphonated poly(phenylene sulphide) terpolymers (sPPSPO) and (ii) their following oxidation with hydrogen peroxide in acidic solution to yield sulphonated poly(phenylene sulphone) terpolymers (sPPSO2PO). The structures and molecular compositions were confirmed by {sup 1}H and {sup 13}C NMR spectroscopy. The ion exchange capacity (IEC) was adjusted at will choosing the appropriate ratio of sulphonated and unsulphonated monomers. Terpolymers with 1.72 {<=} IEC {<=} 2.32 have been obtained. Sulphonated poly(arylene) ionomers containing only sulphone (-SO{sub 2}-) linkages and phosphine oxide (-PO-) units rather than ether or sulphide in the backbone reveal a high thermal and oxidative stability. Membranes were cast either from dimethylformamide (DMF) or from dimethyl sulphoxide (DMSO) solutions. For all terpolymers some general characteristic trends were observed, such as an increase of the proton conductivity with increasing IEC, water uptake and temperature. The series of sPPSO2PO membranes offered high conductivities at high humidification, however, their performance strongly depends on the relative humidity. The mechanical properties of sulphonated poly(phenylene sulphone)s have been considerably improved by means of terpolymerisation with phenylene oxide moieties. Even under high humidification the terpolymers form clear, flexible membranes the stress at break of some membranes exceeds that of

  3. Dihydropyridazinone cardiotonics: discovery of LY195115 and elucidation of structural features necessary for optimal inotropic activity

    International Nuclear Information System (INIS)

    Krushinski, J.H.; Hayes, J.S.; Beedle, E.E.; Pollock, G.D.; Wilson, H.; Robertson, D.W.

    1986-01-01

    A series of 4,5-dihydro-6-aryl-3( 2 H)-pyridazinones has been examined for inotropic activity. The optimal compound of the series, LY195115 (1,3-dihydro-3,3-dimethyl-5-(1,4,5,6-tetrahydro-6-oxo-3-pyridazinyl)- 2 H-indol-2-one), is one of the most potent and long-acting oral inotropes described to date. ED 50 's of LY195115, CI-914 and milrinone after i.v. administration to pentobarbital anesthetized dogs were 6.8, 46 and 37 μg/kg, respectively. ED 50 's after oral administration to conscious dogs were 25, 1000 and 500 μg/kg, respectively. For optimal positive inotropic activity and oral bioavailability in this series, the following structural features are necessary: (1) dihydropyridazinone ring with the nitrogen unsubstituted; (2) a hydrogen-bond acceptor substituent with a σ value of ca 0.0 para to the dihydropyridazinone moiety; and (3) additional sterically undemanding lipophilic substituents adjacent to the hydrogen-bond acceptor site

  4. A Nitric Oxide-Donor Furoxan Moiety Improves the Efficacy of Edaravone against Early Renal Dysfunction and Injury Evoked by Ischemia/Reperfusion

    Directory of Open Access Journals (Sweden)

    Fausto Chiazza

    2015-01-01

    Full Text Available Edaravone (5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, EDV is a free-radical scavenger reduces organ ischemic injury. Here we investigated whether the protective effects of EDV in renal ischemia/reperfusion (I/R injury may be enhanced by an EDV derivative bearing a nitric oxide- (NO- donor furoxan moiety (NO-EDV. Male Wistar rats were subjected to renal ischemia (45 minutes, followed by reperfusion (6 hours. Administration of either EDV (1.2–6–30 µmol/kg, i.v. or NO-EDV (0.3–1.2–6 µmol/kg, i.v. dose-dependently attenuated markers of renal dysfunction (serum urea and creatinine, creatinine clearance, urine flow, urinary N-acetyl-β-D-glucosaminidase, and neutrophil gelatinase-associated lipocalin/lipocalin-2. NO-EDV exerted protective effects in the dose-range 1.2–6 µmol/kg, while a higher dose (30 µmol/kg was needed to obtain protection by EDV. Both EDV and NO-EDV modulated tissue markers of oxidative stress and lipid peroxidation. NO-EDV, but not EDV, activated endothelial NO synthase (NOS and blunted I/R-induced upregulation of inducible NOS, secondary to modulation of Akt and NF-κB activation, respectively. Besides NO-EDV administration inhibited I/R-induced IL-1β, IL-18, IL-6, and TNF-α overproduction. Overall, these findings demonstrate that the NO-donor moiety contributes to the protection against early renal I/R injury and suggest that NO-donor EDV codrugs are worthy of additional study as innovative pharmacological tools.

  5. Functionalization of Chitosan with 3,4,5-Trihydroxy Benzoic Acid Moiety for The Uptake of Chromium Species

    Directory of Open Access Journals (Sweden)

    Akhmad Sabarudin

    2013-03-01

    Full Text Available Chitosan-based chelating resin, the cross-linked chitosan functionalized with 3,4,5-trihydroxy benzoic acid moiety (CCTS-THBA resin, was newly synthesized and its adsorption behavior toward appropriate elements was investigated. At pH 5-9, the CCTS-THBA resin showed quantitative adsorption (87-91% for Cr (VI, while only < 15% for Cr (III. The addition of cyclohexanediamine tetraacetic acid (CyDTA to the samples resulted in a considerably increase of the adsorption of both chromium species. In this condition, Cr (III is chelated with CyDTA to form anionic complexes at pH 3-5, which was then completely adsorbed on the resin by ion exchange mechanism. Similarly, the adsorption of Cr (VI reached almost 100% in pH range of 3-6. The adsorption capacity of CCTS-THBA resin for Cr (VI was 109 mg g-1.

  6. Synthesis and biological activity of some 1,3-dihydro-2H-3-benzazepin-2-ones with a piperazine moiety as bradycardic agents.

    Science.gov (United States)

    Liang, Hong-Yu; Zhang, Deng-Qing; Yue, Yun; Shi, Zhe; Zhao, Sheng-Yin

    2010-02-01

    A series of 1,3-dihydro-2H-3-benzazepin-2-ones with a piperazine moiety were designed and synthesized by treating the common intermediate of 1,3-dihydro-7,8-dimethoxy-3-[3-(1-piperazinyl)propyl]-2H-3-benzazepin-2-ones with a variety of N-aryl-2-chloroacetamides and acyl chlorides. Their structures have been characterized by (1)H-NMR, MS, and elemental analysis. The title compounds were evaluated for their bradycardic activity in vitro. Most of the synthesized compounds exhibited some vasorelaxant activity and heart-rate-reducing activity with bradycardic potency.

  7. New Features in the Lipid A Structure of Brucella suis and Brucella abortus Lipopolysaccharide

    Science.gov (United States)

    Casabuono, Adriana C.; Czibener, Cecilia; Del Giudice, Mariela G.; Valguarnera, Ezequiel; Ugalde, Juan E.; Couto, Alicia S.

    2017-12-01

    Brucellaceae are Gram-negative bacteria that cause brucellosis, one of the most distributed worldwide zoonosis, transmitted to humans by contact with either infected animals or their products. The lipopolysaccharide exposed on the cell surface has been intensively studied and is considered a major virulence factor of Brucella. In the last years, structural studies allowed the determination of new structures in the core oligosaccharide and the O-antigen of this lipopolysaccharide. In this work, we have reinvestigated the lipid A structure isolated from B. suis and B. abortus lipopolysaccharides. A detailed study by MALDI-TOF mass spectrometry in the positive and negative ion modes of the lipid A moieties purified from both species was performed. Interestingly, a new feature was detected: the presence of a pyrophosphorylethanolamine residue substituting the backbone. LID-MS/MS analysis of some of the detected ions allowed assurance that the Lipid A structure composed by the diGlcN3N disaccharide, mainly hexa-acylated and penta-acylated, bearing one phosphate and one pyrophosphorylethanolamine residue. [Figure not available: see fulltext.

  8. New Poly(amide-imide)/Nanocomposites Reinforced Silicate Nanoparticles Based on N-pyromellitimido-L-phenyl Alanine Containing Ether Moieties

    Science.gov (United States)

    Faghihi, Khalil; Shabanian, Meisam; Dadfar, Ehsan

    2012-02-01

    A series of Poly(amide-imide)/montmorillonite nanocomposites containing N-pyromellitimido-L-phenyl alanine moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 5 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N-pyromellitimido-L-phenyl alanine 3 with 4,4'-diamino diphenyl ether 4 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). The resulting nanocomposite films were characterized by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The results showed that organo-modified clay was dispersed homogeneously in PAI matrix. TGA indicated an enhancement of thermal stability of new nanocomposites compared with the pure polymer.

  9. Electron Transfer and Geometric Conversion of Co-NO Moiety in Saddled Porphyrins: Implications for Trigger Role of Tetrapyrrole Distortion.

    Science.gov (United States)

    Tang, Min; Yang, Yan; Zhang, Shaowei; Chen, Jiafu; Zhang, Jian; Zhou, Zaichun; Liu, Qiuhua

    2018-01-02

    The electrons of NO and Co are strongly delocalized in normal {Co-NO} 8 species. In this work, {Co-NO} 8 complexes are induced to convert from (Co II ) +• -NO • to Co III -NO - by a core contraction of 0.06 Å in saddled cobalt(II) porphyrins. This intramolecular electron transfer mechanism indicates that nonplanarity of porphyrin is involved in driving conversion of the NO units from electrophilic NO • as a bent geometry to nucleophilic NO - as a linear geometry. This implies that distortion acts as a trigger in enzymes containing tetrapyrrole. The electronic behaviors of the Co II ions and Co-NO moieties were confirmed by X-ray crystallography, EPR spectroscopy, theoretical calculation, UV-vis and IR spectroscopy, and electrochemistry.

  10. 3D printed modular centrifugal contactors and method for separating moieties using 3D printed optimized surfaces

    Science.gov (United States)

    Wardle, Kent E.

    2017-08-29

    The present invention provides an annular centrifugal contactor, having a housing to receive a plurality of liquids; a rotor inside the housing; an annular mixing zone, with a plurality of fluid retention reservoirs; and an adjustable stem that can be raised to restrict the flow of a liquid into the rotor or lowered to increase the flow of liquid into the rotor. The invention also provides a method for transferring moieties from a first liquid to a second liquid, the method having the steps of combining the fluids in a housing whose interior has helically shaped first channels; subjecting the fluids to a spinning rotor to produce a mixture, whereby the channels simultaneously conduct the mixture downwardly and upwardly; and passing the mixture through the rotor to contact second channels, whereby the channels pump the second liquid through a first aperture while the first fluid exits a second aperture.

  11. Hybrid fluorescent nanoparticles fabricated from pyridine-functionalized polyfluorene-based conjugated polymer as reversible pH probes over a broad range of acidity-alkalinity

    International Nuclear Information System (INIS)

    Cui, Haijun; Chen, Ying; Li, Lianshan; Tang, Zhiyong; Wu, Yishi; Fu, Hongbing; Tian, Zhiyuan

    2014-01-01

    Conjugated polymer nanoparticles (CPNs) were developed based on a polyfluorene-based conjugated polymer with thiophene units carrying pyridyl moieties incorporated in the backbone of polymer chains (PFPyT). Hybrid CPNs fabricated from PFPyT and an amphiphilic polymer (NP1) displayed pH-sensitive fluorescence emission features in the range from pH 4.8 to 13, which makes them an attractive nanomaterial for wide range optical sensing of pH values. The fluorescence of hybrid CPNs based on chemically close polyfluorene derivatives without pyridyl moieties (NP3), in contrast, remains virtually unperturbed by pH values in the same range. The fluorescence emission features of NP1 underwent fully reversible changes upon alternating acidification/basification of aqueous dispersions of the CPNs and also displayed excellent repeatability. The observed pH sensing properties of NP1 are attributed to protonation/deprotonation of the nitrogen atoms of the pyridine moieties. This, in turn, leads to the redistribution of electron density of pyridine moieties and their participation in the π-conjugation within the polymer main chains. The optically transparent amphiphilic polymers also exerted significant influence on the pH sensing features of the CPNs, likely by acting as proton sponge and/or acid chaperone. (author)

  12. Synthesis and Positive Inotropic Activity of [1,2,4]Triazolo[4,3-a] Quinoxaline Derivatives Bearing Substituted Benzylpiperazine and Benzoylpiperazine Moieties

    Directory of Open Access Journals (Sweden)

    Xue-Kun Liu

    2017-02-01

    Full Text Available In an attempt to search for more potent positive inotropic agents, two series of [1,2,4]triazolo[4,3-a] quinoxaline derivatives bearing substituted benzylpiperazine and benzoylpiperazine moieties were synthesized and their positive inotropic activities evaluated by measuring left atrial stroke volume in isolated rabbit heart preparations. Several compounds showed favorable activities compared with the standard drug, milrinone. Compound 6c was the most potent agent, with an increased stroke volume of 12.53% ± 0.30% (milrinone: 2.46% ± 0.07% at 3 × 10−5 M. The chronotropic effects of compounds having considerable inotropic effects were also evaluated.

  13. New carbocyclic nucleoside analogues with a bicyclo[2.2.1]heptane fragment as sugar moiety; synthesis, X-ray crystallography and anticancer activity.

    Science.gov (United States)

    Tănase, Constantin I; Drăghici, Constantin; Căproiu, Miron Teodor; Shova, Sergiu; Mathe, Christophe; Cocu, Florea G; Enache, Cristian; Maganu, Maria

    2014-01-01

    An amine group was synthesized starting from an optically active bicyclo[2.2.1]heptane compound, which was then used to build the 5 atoms ring of a key 6-chloropurine intermediate. This was then reacted with ammonia and selected amines obtaining new adenine- and 6-substituted adenine conformationally constrained carbocyclic nucleoside analogues with a bicyclo[2.2.1]heptane skeleton in the sugar moiety. X-ray crystallography confirmed an exo-coupling of base to the ring and a L configuration of the nucleoside analogues. The compounds were tested for anticancer activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. The effects of conformational constraints and steric bulk in the amino acid moiety of philanthotoxins on AMPAR antagonism

    DEFF Research Database (Denmark)

    Jørgensen, Malene; Olsen, Christian A; Mellor, Ian R

    2005-01-01

    , establishing general protocols for philanthotoxin solution- and solid-phase synthesis (39-90% and 42-54% overall yields, respectively). The analogues were tested for their ability to antagonize kainate-induced currents of 2-amino-3-(3-hydroxy-5-methyl-4-isoxazoyl)propanoic acid receptors (AMPAR) expressed...... in Xenopus oocytes from rat brain mRNA. This showed that steric bulk in the amino acid moiety is well tolerated and suggests that binding to AMPAR does not involve the alpha-NHCO group as a donor in hydrogen bonding.......Philanthotoxin-343 (PhTX-343), a synthetic analogue of wasp toxin PhTX-433, is a noncompetitive antagonist at ionotropic receptors (e.g., AChR or iGluR). To determine possible effects of variations of the amino acid side chain, a library consisting of seventeen PhTX-343 analogues was prepared. Thus...

  15. Synthesis, characterization and gas separation properties of novel polyimides containing cardo and tert-butyl-m-terphenyl moieties

    Directory of Open Access Journals (Sweden)

    L. A. Bermejo

    2018-05-01

    Full Text Available A series of aromatic polyimides has been obtained by the reaction of two dianhydrides, the commercial 2,2′-bis(3,4-dicarboxyphenylhexafluoropropane dianhydride (6FDA and another having a 5′-tert-butyl-m-terphenyl moiety (BTPDA, with several diamines, including two that have a cardo structure (derived from 9H-fluorene, one of them bearing methyl groups ortho to the amino functionalities (TMeCardo. The solubility, and also the thermal, mechanical, and gas separation properties of the corresponding polyimide membranes were evaluated and compared in order to explore the effect of the different groups in the polyimide backbone. The novel polyimides, which were derived from BTPDA and the cardo diamines, showed high thermal stability, excellent solubility in organic solvents and good gas separation properties, especially the polyimide that bore the ortho methyl substituents. The behavior was especially good for the pair O2/N2, where the TMeCardo polymer overpassed the Robeson upper bound.

  16. Dihydropyridazinone cardiotonics: discovery of LY195115 and elucidation of structural features necessary for optimal inotropic activity

    Energy Technology Data Exchange (ETDEWEB)

    Krushinski, J.H.; Hayes, J.S.; Beedle, E.E.; Pollock, G.D.; Wilson, H.; Robertson, D.W.

    1986-03-05

    A series of 4,5-dihydro-6-aryl-3(/sup 2/H)-pyridazinones has been examined for inotropic activity. The optimal compound of the series, LY195115 (1,3-dihydro-3,3-dimethyl-5-(1,4,5,6-tetrahydro-6-oxo-3-pyridazinyl)-/sup 2/H-indol-2-one), is one of the most potent and long-acting oral inotropes described to date. ED/sub 50/'s of LY195115, CI-914 and milrinone after i.v. administration to pentobarbital anesthetized dogs were 6.8, 46 and 37 ..mu..g/kg, respectively. ED/sub 50/'s after oral administration to conscious dogs were 25, 1000 and 500 ..mu..g/kg, respectively. For optimal positive inotropic activity and oral bioavailability in this series, the following structural features are necessary: (1) dihydropyridazinone ring with the nitrogen unsubstituted; (2) a hydrogen-bond acceptor substituent with a sigma value of ca 0.0 para to the dihydropyridazinone moiety; and (3) additional sterically undemanding lipophilic substituents adjacent to the hydrogen-bond acceptor site.

  17. Heliotropiumides A and B, new phenolamides with N-carbamoyl putrescine moiety from Heliotropium foertherianum collected in Hawaii and their biological activities.

    Science.gov (United States)

    Cai, You-Sheng; Sarotti, Ariel M; Gündisch, Daniela; Kondratyuk, Tamara P; Pezzuto, John M; Turkson, James; Cao, Shugeng

    2017-10-15

    Two new compounds heliotropiumides A (1) and B (2), phenolamides each with an uncommon carbamoyl putrescine moiety, were isolated from the seeds of a naturalized Hawaiian higher plant, Heliotropium foertherianum Diane & Hilger in the borage family, which is widely used for the treatment of ciguatera fish poisoning. The structures of compounds 1 and 2 were characterized based on MS spectroscopic and NMR analysis, and DP4+ calculations. The absolute configuration (AC) of compound 1 was determined by comparison of its optical rotation with those reported in literature. Compound 2 showed inhibition against NF-κB with an IC 50 value of 36μM. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. A prototype feature system for feature retrieval using relationships

    Science.gov (United States)

    Choi, J.; Usery, E.L.

    2009-01-01

    Using a feature data model, geographic phenomena can be represented effectively by integrating space, theme, and time. This paper extends and implements a feature data model that supports query and visualization of geographic features using their non-spatial and temporal relationships. A prototype feature-oriented geographic information system (FOGIS) is then developed and storage of features named Feature Database is designed. Buildings from the U.S. Marine Corps Base, Camp Lejeune, North Carolina and subways in Chicago, Illinois are used to test the developed system. The results of the applications show the strength of the feature data model and the developed system 'FOGIS' when they utilize non-spatial and temporal relationships in order to retrieve and visualize individual features.

  19. Different cell moieties and white blood cell (WBC) integrity in In-111 labeled WBC preparations

    International Nuclear Information System (INIS)

    Saha, G.B.; Feiglin, D.H.I.; McMahon, J.T.; Go, R.T.; O'Donnell, J.K.; MacIntyre, W.J.

    1985-01-01

    Indium-111 labeled white blood cells (WBC) have become very popular in detecting inflammatory diseases. The purpose of this paper is to determine the distribution of different types of cells in WBC preparation for In-111 oxine labeling, and also to assess the histological integrity of WBC's after labeling with In-111 oxine. Forty to fifty cc of blood was collected from each patient and WBC's were separated by sedimentation and centrifugation. After labeling with In-111 oxine, an aliquot of the WBC sample was used for cell counting and a second aliquot was used for electron microscopic (EM) examination. The different cell moieties were counted, and the mean and standard deviation of twelve determinations calculated. Cells were prepared by the standard technique for electron microscopic examination and images of the cells were obtained at different magnifications (X8,000-25,000). The EM images revealed that although minimal cytoplasmic vacuolization occurred in the WBC's due to the labeling process, the overall histological integrity of the cells remained intact. The relative labeling efficiency of WBC's is greater than those of RBC's and platelets (J Nuc) Med 25:p98, 1984) and, therefore, even a comparatively low population of WBC's gives optimal imaging due to their increased tracer uptake

  20. Enhancing facial features by using clear facial features

    Science.gov (United States)

    Rofoo, Fanar Fareed Hanna

    2017-09-01

    The similarity of features between individuals of same ethnicity motivated the idea of this project. The idea of this project is to extract features of clear facial image and impose them on blurred facial image of same ethnic origin as an approach to enhance a blurred facial image. A database of clear images containing 30 individuals equally divided to five different ethnicities which were Arab, African, Chines, European and Indian. Software was built to perform pre-processing on images in order to align the features of clear and blurred images. And the idea was to extract features of clear facial image or template built from clear facial images using wavelet transformation to impose them on blurred image by using reverse wavelet. The results of this approach did not come well as all the features did not align together as in most cases the eyes were aligned but the nose or mouth were not aligned. Then we decided in the next approach to deal with features separately but in the result in some cases a blocky effect was present on features due to not having close matching features. In general the available small database did not help to achieve the goal results, because of the number of available individuals. The color information and features similarity could be more investigated to achieve better results by having larger database as well as improving the process of enhancement by the availability of closer matches in each ethnicity.

  1. Spatial features register: toward standardization of spatial features

    Science.gov (United States)

    Cascio, Janette

    1994-01-01

    As the need to share spatial data increases, more than agreement on a common format is needed to ensure that the data is meaningful to both the importer and the exporter. Effective data transfer also requires common definitions of spatial features. To achieve this, part 2 of the Spatial Data Transfer Standard (SDTS) provides a model for a spatial features data content specification and a glossary of features and attributes that fit this model. The model provides a foundation for standardizing spatial features. The glossary now contains only a limited subset of hydrographic and topographic features. For it to be useful, terms and definitions must be included for other categories, such as base cartographic, bathymetric, cadastral, cultural and demographic, geodetic, geologic, ground transportation, international boundaries, soils, vegetation, water, and wetlands, and the set of hydrographic and topographic features must be expanded. This paper will review the philosophy of the SDTS part 2 and the current plans for creating a national spatial features register as one mechanism for maintaining part 2.

  2. Characterisation of the Native Lipid Moiety of Echinococcus granulosus Antigen B

    Science.gov (United States)

    Obal, Gonzalo; Ramos, Ana Lía; Silva, Valeria; Lima, Analía; Batthyany, Carlos; Bessio, María Inés; Ferreira, Fernando; Salinas, Gustavo; Ferreira, Ana María

    2012-01-01

    Antigen B (EgAgB) is the most abundant and immunogenic antigen produced by the larval stage (metacestode) of Echinococcus granulosus. It is a lipoprotein, the structure and function of which have not been completely elucidated. EgAgB apolipoprotein components have been well characterised; they share homology with a group of hydrophobic ligand binding proteins (HLBPs) present exclusively in cestode organisms, and consist of different isoforms of 8-kDa proteins encoded by a polymorphic multigene family comprising five subfamilies (EgAgB1 to EgAgB5). In vitro studies have shown that EgAgB apolipoproteins are capable of binding fatty acids. However, the identity of the native lipid components of EgAgB remains unknown. The present work was aimed at characterising the lipid ligands bound to EgAgB in vivo. EgAgB was purified to homogeneity from hydatid cyst fluid and its lipid fraction was extracted using chloroform∶methanol mixtures. This fraction constituted approximately 40–50% of EgAgB total mass. High-performance thin layer chromatography revealed that the native lipid moiety of EgAgB consists of a variety of neutral (mainly triacylglycerides, sterols and sterol esters) and polar (mainly phosphatidylcholine) lipids. Gas-liquid chromatography analysis showed that 16∶0, 18∶0 and 18∶1(n-9) are the most abundant fatty acids in EgAgB. Furthermore, size exclusion chromatography coupled to light scattering demonstrated that EgAgB comprises a population of particles heterogeneous in size, with an average molecular mass of 229 kDa. Our results provide the first direct evidence of the nature of the hydrophobic ligands bound to EgAgB in vivo and indicate that the structure and composition of EgAgB lipoprotein particles are more complex than previously thought, resembling high density plasma lipoproteins. Results are discussed considering what is known on lipid metabolism in cestodes, and taken into account the Echinococcus spp. genomic information regarding both lipid

  3. Characterisation of the native lipid moiety of Echinococcus granulosus antigen B.

    Directory of Open Access Journals (Sweden)

    Gonzalo Obal

    Full Text Available Antigen B (EgAgB is the most abundant and immunogenic antigen produced by the larval stage (metacestode of Echinococcus granulosus. It is a lipoprotein, the structure and function of which have not been completely elucidated. EgAgB apolipoprotein components have been well characterised; they share homology with a group of hydrophobic ligand binding proteins (HLBPs present exclusively in cestode organisms, and consist of different isoforms of 8-kDa proteins encoded by a polymorphic multigene family comprising five subfamilies (EgAgB1 to EgAgB5. In vitro studies have shown that EgAgB apolipoproteins are capable of binding fatty acids. However, the identity of the native lipid components of EgAgB remains unknown. The present work was aimed at characterising the lipid ligands bound to EgAgB in vivo. EgAgB was purified to homogeneity from hydatid cyst fluid and its lipid fraction was extracted using chloroform∶methanol mixtures. This fraction constituted approximately 40-50% of EgAgB total mass. High-performance thin layer chromatography revealed that the native lipid moiety of EgAgB consists of a variety of neutral (mainly triacylglycerides, sterols and sterol esters and polar (mainly phosphatidylcholine lipids. Gas-liquid chromatography analysis showed that 16∶0, 18∶0 and 18∶1(n-9 are the most abundant fatty acids in EgAgB. Furthermore, size exclusion chromatography coupled to light scattering demonstrated that EgAgB comprises a population of particles heterogeneous in size, with an average molecular mass of 229 kDa. Our results provide the first direct evidence of the nature of the hydrophobic ligands bound to EgAgB in vivo and indicate that the structure and composition of EgAgB lipoprotein particles are more complex than previously thought, resembling high density plasma lipoproteins. Results are discussed considering what is known on lipid metabolism in cestodes, and taken into account the Echinococcus spp. genomic information regarding

  4. FEATURE SELECTION METHODS BASED ON MUTUAL INFORMATION FOR CLASSIFYING HETEROGENEOUS FEATURES

    Directory of Open Access Journals (Sweden)

    Ratri Enggar Pawening

    2016-06-01

    Full Text Available Datasets with heterogeneous features can affect feature selection results that are not appropriate because it is difficult to evaluate heterogeneous features concurrently. Feature transformation (FT is another way to handle heterogeneous features subset selection. The results of transformation from non-numerical into numerical features may produce redundancy to the original numerical features. In this paper, we propose a method to select feature subset based on mutual information (MI for classifying heterogeneous features. We use unsupervised feature transformation (UFT methods and joint mutual information maximation (JMIM methods. UFT methods is used to transform non-numerical features into numerical features. JMIM methods is used to select feature subset with a consideration of the class label. The transformed and the original features are combined entirely, then determine features subset by using JMIM methods, and classify them using support vector machine (SVM algorithm. The classification accuracy are measured for any number of selected feature subset and compared between UFT-JMIM methods and Dummy-JMIM methods. The average classification accuracy for all experiments in this study that can be achieved by UFT-JMIM methods is about 84.47% and Dummy-JMIM methods is about 84.24%. This result shows that UFT-JMIM methods can minimize information loss between transformed and original features, and select feature subset to avoid redundant and irrelevant features.

  5. Dual pancreas- and lung-targeting therapy for local and systemic complications of acute pancreatitis mediated by a phenolic propanediamine moiety.

    Science.gov (United States)

    Li, Jianbo; Zhang, Jinjie; Fu, Yao; Sun, Xun; Gong, Tao; Jiang, Jinghui; Zhang, Zhirong

    2015-08-28

    To inhibit both the local and systemic complications with acute pancreatitis, an effective therapy requires a drug delivery system that can efficiently overcome the blood-pancreas barrier while achieving lung-specific accumulation. Here, we report the first dual pancreas- and lung-targeting therapeutic strategy mediated by a phenolic propanediamine moiety for the treatment of acute pancreatitis. Using the proposed dual-targeting ligand, an anti-inflammatory compound Rhein has been tailored to preferentially accumulate in the pancreas and lungs with rapid distribution kinetics, excellent tissue-penetrating properties and minimum toxicity. Accordingly, the drug-ligand conjugate remarkably downregulated the proinflammatory cytokines in the target organs thus effectively inhibiting local pancreatic and systemic inflammation in rats. The dual-specific targeting therapeutic strategy may help pave the way for targeted drug delivery to treat complicated inflammatory diseases. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Novel poly(triphenylamine-alt-fluorene) with asymmetric hexaphenylbenzene and pyrene moieties: synthesis, fluorescence, flexible near-infrared electrochromic devices and theoretical investigation

    KAUST Repository

    Wang, Po-I.

    2016-01-13

    © The Royal Society of Chemistry 2016. In this study, a new triphenylamine-alt-fluorene conjugated copolymer, HPBPYFL6, with hexaphenylbenzene (HPB) and pyrene as asymmetrical pendant groups was synthesized via Suzuki coupling polymerization. The conjugated polymer had a weight-average molecular weight of 5.8 × 104 g mol-1 with a polydispersity index of 2.5 characterized by gel permeation chromatography (GPC). HPBPYFL6 showed good solubility in common organic solvents such as NMP, THF, toluene and dichloromethane at 25°C. In addition, HPBPYFL6 possessed a high glass transition temperature of 260°C and a 10% weight-loss temperature of 503°C in nitrogen. HPBPYFL6 bearing a pyrene moiety had a solvatochromic fluorescence shift from a green to an orange emission as the polarity of the solvent increased. Cyclic voltammetry of HPBPYFL6 films cast onto indium-tin oxide-coated glass (ITO-glass) exhibited two oxidation redox couples at an E1/2 value of 0.82 and 1.17 V versus Ag/Ag+ in an acetonitrile solution. The HPBPYFL6 film on graphene-coated PET had an E1/2 value of 0.24 and 1.12 V. Conjugated polymer films exhibited reversible electrochromic behaviour with a colour change from pale yellow to deep blue upon electrochemical oxidation and high absorbance in the near-infrared (NIR) region. The switching and bleaching times were 5.16 s and 3.12 s for 1231 nm and were 3.30 s and 3.74 s for 1030 nm of HPBPYFL6 on ITO-glass. The strong NIR electrochromic absorbance of HPBPYFL6 was attributed to intervalence charge transfer by the incorporation of the HPB moiety. This phenomenon was confirmed by chemical oxidation as the oxidant contents increased in the solution state. Furthermore, the electrochromic mechanism was interpreted by DFT calculation and the simulated NIR electrochromic spectra of model compound HPBPYFL are in good agreement with the experimental data.

  7. Identifying significant environmental features using feature recognition.

    Science.gov (United States)

    2015-10-01

    The Department of Environmental Analysis at the Kentucky Transportation Cabinet has expressed an interest in feature-recognition capability because it may help analysts identify environmentally sensitive features in the landscape, : including those r...

  8. Cover Feature: LEGO-Inspired Drug Design: Unveiling a Class of Benzo[d]thiazoles Containing a 3,4-Dihydroxyphenyl Moiety as Plasma Membrane H+-ATPase Inhibitors (ChemMedChem 1/2018)

    DEFF Research Database (Denmark)

    Thanh Tung, Truong; Dao, Trong Tuan; Grifell Junyent, Marta

    2018-01-01

    The Cover Feature shows a rational procedure for assembling privileged molecular fragments (like playing with LEGO bricks) to obtain hit structures. We have invented a novel procedure for targeting biological macromolecules possessing a binding site with a poorly known topography. We have coined ......, 2018 (DOI: 10.1002/cmdc.201700635)....

  9. Analytical Features: A Knowledge-Based Approach to Audio Feature Generation

    Directory of Open Access Journals (Sweden)

    Pachet François

    2009-01-01

    Full Text Available We present a feature generation system designed to create audio features for supervised classification tasks. The main contribution to feature generation studies is the notion of analytical features (AFs, a construct designed to support the representation of knowledge about audio signal processing. We describe the most important aspects of AFs, in particular their dimensional type system, on which are based pattern-based random generators, heuristics, and rewriting rules. We show how AFs generalize or improve previous approaches used in feature generation. We report on several projects using AFs for difficult audio classification tasks, demonstrating their advantage over standard audio features. More generally, we propose analytical features as a paradigm to bring raw signals into the world of symbolic computation.

  10. Facile synthesis and antimicrobial evaluation of some new heterocyclic compounds incorporating a biologically active sulfamoyl moiety.

    Science.gov (United States)

    Darwish, Elham S

    2014-01-01

    A facile and convenient synthesis of new heterocyclic compounds containing a sulfamoyl moiety suitable for use as antimicrobial agents was reported. The precursor 3-oxo-3-phenyl-N-(4-sulfamoylphenyl)propionamide was coupled smoothly with arenediazonium salt producing hydrazones which reacted with malononitrile or triethylorthoformate affording pyridazine and triazine derivatives, respectively. Also, the reactivity of the same precursor with DMF-DMA was followed by aminotriazole; aromatic aldehydes was followed by hydrazine hydrate, triethylorthoformate, or thiourea affording triazolo[1,5-a]pyrimidine, pyrazole, acrylamide, and dihydropyrimidine derivatives, respectively. On the other hand, treatment of the precursor propionamide with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt which was treated with dilute HCl followed by 2-bromo-1-phenylethanone affording carboxamide derivative. While the same intermediate salt reacted in situ with chloroacetone, ethyl 2-chloroacetate, 3-(2-bromoacetyl)-2H-chromen-2-one, methyl iodide, or 2-oxo-N-phenylpropane hydrazonoyl chloride afforded the thiophene, ketene N,S-acetal, and thiadiazole derivatives, respectively. The structure of the new products was established based on elemental and spectral analysis. Antimicrobial evaluation of some selected examples from the synthesized products was carried out whereby four compounds were found to have moderate activities and one compound showed the highest activity.

  11. Featureous: infrastructure for feature-centric analysis of object-oriented software

    DEFF Research Database (Denmark)

    Olszak, Andrzej; Jørgensen, Bo Nørregaard

    2010-01-01

    The decentralized nature of collaborations between objects in object-oriented software makes it difficult to understand how user-observable program features are implemented and how their implementations relate to each other. It is worthwhile to improve this situation, since feature-centric program...... understanding and modification are essential during software evolution and maintenance. In this paper, we present an infrastructure built on top of the NetBeans IDE called Featureous that allows for rapid construction of tools for feature-centric analysis of object-oriented software. Our infrastructure...... encompasses a lightweight feature location mechanism, a number of analytical views and an API allowing for addition of third-party extensions. To form a common conceptual framework for future feature-centric extensions, we propose to structure feature centric analysis along three dimensions: perspective...

  12. Molecular and polymeric uranyl and thorium hybrid materials featuring methyl substituted pyrazole dicarboxylates and heterocyclic 1,3-diketones

    Science.gov (United States)

    Carter, Korey P.; Kerr, Andrew T.; Taydakov, Ilya V.; Cahill, Christopher L.

    2018-02-01

    A series of seven novel f-element bearing hybrid materials have been prepared from either methyl substituted 3,4 and 4,5-pyrazoledicarboxylic acids, or heterocyclic 1,3- diketonate ligands using hydrothermal conditions. Compounds 1, [UO2(C6H4N2O4)2(H2O)], and 3, [Th(C6H4N2O4)4(H2O)5]·H2O feature 1-Methyl-1H-pyrazole-3,4-dicarboxylate ligands (SVI-COOH 3,4), whereas 2, [UO2(C6H4N2O4)2(H2O)], and 4, [Th(C6H5N2O4)(OH)(H2O)6]2·2(C6H5N2O4)·3H2O feature 1-Methyl-1H-pyrazole-4,5-dicarboxylate moieties (SVI-COOH 4,5). Compounds 5, [UO2(C13H15N4O2)2(H2O)]·2H2O and 6, [UO2(C11H11N4O2)2(H2O)]·4.5H2O feature 1,3-bis(4-N1-methyl-pyrazolyl)propane-1,3-dione and 1,3-bis(4-N1,3-dimethyl-pyrazolyl)propane-1,3-dione respectively, whereas the heterometallic 7, [UO2(C11H11N4O2)2(CuCl2)(H2O)]·2H2O is formed by using 6 as a metalloligand starting material. Single crystal X-ray diffraction indicates that all coordination to either [UO2]2+ or Th(IV) metal centers is through O-donation as anticipated. Room temperature, solid-state luminescence studies indicate characteristic uranyl emissive behavior for 1 and 2, whereas those for 5 and 6 are weak and poorly resolved.

  13. Feature Article

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Feature Article. Articles in Resonance – Journal of Science Education. Volume 1 Issue 1 January 1996 pp 80-85 Feature Article. What's New in Computers Windows 95 · Vijnan Shastri · More Details Fulltext PDF. Volume 1 Issue 1 January 1996 pp 86-89 Feature ...

  14. Featureous: A Tool for Feature-Centric Analysis of Java Software

    DEFF Research Database (Denmark)

    Olszak, Andrzej; Jørgensen, Bo Nørregaard

    2010-01-01

    Feature-centric comprehension of source code is necessary for incorporating user-requested modifications during software evolution and maintenance. However, such comprehension is difficult to achieve in case of large object-oriented programs due to the size, complexity, and implicit character...... of mappings between features and source code. To support programmers in overcoming these difficulties, we present a feature-centric analysis tool, Featureous. Our tool extends the NetBeans IDE with mechanisms for efficient location of feature implementations in legacy source code, and an extensive analysis...

  15. Diazonium salt-mediated synthesis of new amino, hydroxy, propargyl, and maleinimido-containing superparamagnetic Fe@C nanoparticles as platforms for linking bio-entities or organocatalytic moieties

    International Nuclear Information System (INIS)

    Bunge, Alexander; Magerusan, Lidia; Morjan, Ion; Turcu, Rodica; Borodi, Gheorghe; Liebscher, Jürgen

    2015-01-01

    New magnetic Fe@C nanoparticles in the size range of about 20–50 nm functionalized with amino, hydroxy, propargyl, or maleinimido groups were synthesized by reaction with aryl diazonium salts. Aryl diazonium salts wherein the functional groups are linked via a sulfonamide moiety turned out to be advantageous over those with direct linkage. The obtained Fe@C nanoparticles represent magnetic nanoplatforms for linking bio-entities and organocatalysts using amide formation, CuAAC, or thiol-ene click chemistry as exemplified by selected examples. The Fe@C nanoparticles obtained exhibit supramolecular behavior with high value of saturation magnetization rendering them attractive for practical applications in biomedicine and organocatalysis.

  16. Diazonium salt-mediated synthesis of new amino, hydroxy, propargyl, and maleinimido-containing superparamagnetic Fe@C nanoparticles as platforms for linking bio-entities or organocatalytic moieties

    Science.gov (United States)

    Bunge, Alexander; Magerusan, Lidia; Morjan, Ion; Turcu, Rodica; Borodi, Gheorghe; Liebscher, Jürgen

    2015-09-01

    New magnetic Fe@C nanoparticles in the size range of about 20-50 nm functionalized with amino, hydroxy, propargyl, or maleinimido groups were synthesized by reaction with aryl diazonium salts. Aryl diazonium salts wherein the functional groups are linked via a sulfonamide moiety turned out to be advantageous over those with direct linkage. The obtained Fe@C nanoparticles represent magnetic nanoplatforms for linking bio-entities and organocatalysts using amide formation, CuAAC, or thiol-ene click chemistry as exemplified by selected examples. The Fe@C nanoparticles obtained exhibit supramolecular behavior with high value of saturation magnetization rendering them attractive for practical applications in biomedicine and organocatalysis.

  17. Diazonium salt-mediated synthesis of new amino, hydroxy, propargyl, and maleinimido-containing superparamagnetic Fe@C nanoparticles as platforms for linking bio-entities or organocatalytic moieties

    Energy Technology Data Exchange (ETDEWEB)

    Bunge, Alexander; Magerusan, Lidia [National Institute of Research and Development for Isotopic and Molecular Technologies (Romania); Morjan, Ion [National Institute for Lasers, Plasma and Radiation Physics (Romania); Turcu, Rodica; Borodi, Gheorghe; Liebscher, Jürgen, E-mail: liebscher@chemie.hu-berlin.de [National Institute of Research and Development for Isotopic and Molecular Technologies (Romania)

    2015-09-15

    New magnetic Fe@C nanoparticles in the size range of about 20–50 nm functionalized with amino, hydroxy, propargyl, or maleinimido groups were synthesized by reaction with aryl diazonium salts. Aryl diazonium salts wherein the functional groups are linked via a sulfonamide moiety turned out to be advantageous over those with direct linkage. The obtained Fe@C nanoparticles represent magnetic nanoplatforms for linking bio-entities and organocatalysts using amide formation, CuAAC, or thiol-ene click chemistry as exemplified by selected examples. The Fe@C nanoparticles obtained exhibit supramolecular behavior with high value of saturation magnetization rendering them attractive for practical applications in biomedicine and organocatalysis.

  18. Hybrid Silicon-Based Organic/Inorganic Block Copolymers with Sol-Gel Active Moieties: Synthetic Advances, Self-Assembly and Applications in Biomedicine and Materials Science.

    Science.gov (United States)

    Czarnecki, Sebastian; Bertin, Annabelle

    2018-03-07

    Hybrid silicon-based organic/inorganic (multi)block copolymers are promising polymeric precursors to create robust nano-objects and nanomaterials due to their sol-gel active moieties via self-assembly in solution or in bulk. Such nano-objects and nanomaterials have great potential in biomedicine as nanocarriers or scaffolds for bone regeneration as well as in materials science as Pickering emulsifiers, photonic crystals or coatings/films with antibiofouling, antibacterial or water- and oil-repellent properties. Thus, this Review outlines recent synthetic efforts in the preparation of these hybrid inorganic/organic block copolymers, gives an overview of their self-assembled structures and finally presents recent examples of their use in the biomedical field and material science. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Co-crystallization phase transformations in all π-conjugated block copolymers with different main-chain moieties.

    Science.gov (United States)

    Lee, Yi-Huan; Chen, Wei-Chih; Yang, Yi-Lung; Chiang, Chi-Ju; Yokozawa, Tsutomu; Dai, Chi-An

    2014-05-21

    Driven by molecular affinity and balance in the crystallization kinetics, the ability to co-crystallize dissimilar yet self-crystallizable blocks of a block copolymer (BCP) into a uniform domain may strongly affect its phase diagram. In this study, we synthesize a new series of crystalline and monodisperse all-π-conjugated poly(2,5-dihexyloxy-p-phenylene)-b-poly(3-(2-ethylhexyl)thiophene) (PPP-P3EHT) BCPs and investigate this multi-crystallization effect. Despite vastly different side-chain and main-chain structures, PPP and P3EHT blocks are able to co-crystallize into a single uniform domain comprising PPP and P3EHT main-chains with mutually interdigitated side-chains spaced in-between. With increasing P3EHT fraction, PPP-P3EHTs undergo sequential phase transitions and form hierarchical superstructures including predominately PPP nanofibrils, co-crystalline nanofibrils, a bilayer co-crystalline/pure P3EHT lamellar structure, a microphase-separated bilayer PPP-P3EHT lamellar structure, and finally P3EHT nanofibrils. In particular, the presence of the new co-crystalline lamellar structure is the manifestation of the interaction balance between self-crystallization and co-crystallization of the dissimilar polymers on the resulting nanostructure of the BCP. The current study demonstrates the co-crystallization nature of all-conjugated BCPs with different main-chain moieties and may provide new guidelines for the organization of π-conjugated BCPs for future optoelectronic applications.

  20. Definitions of engineered safety features and related features for nuclear power plants

    International Nuclear Information System (INIS)

    1986-01-01

    In light water moderated, light water cooled nuclear power plants, definitions are given of engineered safety features which are designed to suppress or prevent dispersion of radioactive materials due to damage etc. of fuel at the times of power plant failures, and of related features which are designed to actuate or operate the engineered safety features. Contents are the following: scope of engineered safety features and of related features; classification of engineered safety features (direct systems and indirect systems) and of related features (auxiliaries, emergency power supply, and protective means). (Mori, K.)

  1. Photocatalytic Conversion of CO2 to CO using Rhenium Bipyridine Platforms Containing Ancillary Phenyl or BODIPY Moieties

    Science.gov (United States)

    Andrade, Gabriel A.; Pistner, Allen J.; Yap, Glenn P.A.; Lutterman, Daniel A.; Rosenthal, Joel

    2013-01-01

    Harnessing of solar energy to drive the reduction of carbon dioxide to fuels requires the development of efficient catalysts that absorb sunlight. In this work, we detail the synthesis, electrochemistry and photophysical properties of a set of homologous fac-ReI(CO)3 complexes containing either an ancillary phenyl (8) or BODIPY (12) substituent. These studies demonstrate that both the electronic properties of the rhenium center and BODIPY chromophore are maintained for these complexes. Photolysis studies demonstrate that both assemblies 8 and 12 are competent catalysts for the photochemical reduction of CO2 to CO in DMF using triethanolamine (TEOA) as a sacrificial reductant. Both compounds 8 and 12 display TOFs for photocatalytic CO production upon irradiation with light (λex ≥ 400 nm) of ~5 hr−1 with TON values of approximately 20. Although structural and photophysical measurements demonstrate that electronic coupling between the BODIPY and fac-ReI(CO)3 units is limited for complex 12, this work clearly shows that the photoactive BODIPY moiety is tolerated during catalysis and does not interfere with the observed photochemistry. When taken together, these results provide a clear roadmap for the development of advanced rhenium bipyridine complexes bearing ancillary BODIPY groups for the efficient photocatalytic reduction of CO2 using visible light. PMID:24015374

  2. Structure elucidation of the new citharoxazole from the Mediterranean deep-sea sponge Latrunculia (Biannulata) citharistae.

    Science.gov (United States)

    Genta-Jouve, Grégory; Francezon, Nellie; Puissant, Alexandre; Auberger, Patrick; Vacelet, Jean; Pérez, Thierry; Fontana, Angelo; Mourabit, Ali Al; Thomas, Olivier P

    2011-08-01

    Citharoxazole (1), a new batzelline derivative featuring a benzoxazole moiety, was isolated from the Mediterranean deep-sea sponge Latrunculia (Biannulata) citharistae Vacelet, 1969, together with the known batzelline C (2). This is the first chemical study of a Mediterranean Latrunculia species and the benzoxazole moiety is unprecedented for this family of marine natural products. The structure was mainly elucidated by the interpretation of NMR spectra and especially HMBC correlations. Copyright © 2011 John Wiley & Sons, Ltd.

  3. JCE Feature Columns

    Science.gov (United States)

    Holmes, Jon L.

    1999-05-01

    The Features area of JCE Online is now readily accessible through a single click from our home page. In the Features area each column is linked to its own home page. These column home pages also have links to them from the online Journal Table of Contents pages or from any article published as part of that feature column. Using these links you can easily find abstracts of additional articles that are related by topic. Of course, JCE Online+ subscribers are then just one click away from the entire article. Finding related articles is easy because each feature column "site" contains links to the online abstracts of all the articles that have appeared in the column. In addition, you can find the mission statement for the column and the email link to the column editor that I mentioned above. At the discretion of its editor, a feature column site may contain additional resources. As an example, the Chemical Information Instructor column edited by Arleen Somerville will have a periodically updated bibliography of resources for teaching and using chemical information. Due to the increase in the number of these resources available on the WWW, it only makes sense to publish this information online so that you can get to these resources with a simple click of the mouse. We expect that there will soon be additional information and resources at several other feature column sites. Following in the footsteps of the Chemical Information Instructor, up-to-date bibliographies and links to related online resources can be made available. We hope to extend the online component of our feature columns with moderated online discussion forums. If you have a suggestion for an online resource you would like to see included, let the feature editor or JCE Online (jceonline@chem.wisc.edu) know about it. JCE Internet Features JCE Internet also has several feature columns: Chemical Education Resource Shelf, Conceptual Questions and Challenge Problems, Equipment Buyers Guide, Hal's Picks, Mathcad

  4. Principal Feature Analysis: A Multivariate Feature Selection Method for fMRI Data

    Directory of Open Access Journals (Sweden)

    Lijun Wang

    2013-01-01

    Full Text Available Brain decoding with functional magnetic resonance imaging (fMRI requires analysis of complex, multivariate data. Multivoxel pattern analysis (MVPA has been widely used in recent years. MVPA treats the activation of multiple voxels from fMRI data as a pattern and decodes brain states using pattern classification methods. Feature selection is a critical procedure of MVPA because it decides which features will be included in the classification analysis of fMRI data, thereby improving the performance of the classifier. Features can be selected by limiting the analysis to specific anatomical regions or by computing univariate (voxel-wise or multivariate statistics. However, these methods either discard some informative features or select features with redundant information. This paper introduces the principal feature analysis as a novel multivariate feature selection method for fMRI data processing. This multivariate approach aims to remove features with redundant information, thereby selecting fewer features, while retaining the most information.

  5. Classification Influence of Features on Given Emotions and Its Application in Feature Selection

    Science.gov (United States)

    Xing, Yin; Chen, Chuang; Liu, Li-Long

    2018-04-01

    In order to solve the problem that there is a large amount of redundant data in high-dimensional speech emotion features, we analyze deeply the extracted speech emotion features and select better features. Firstly, a given emotion is classified by each feature. Secondly, the recognition rate is ranked in descending order. Then, the optimal threshold of features is determined by rate criterion. Finally, the better features are obtained. When applied in Berlin and Chinese emotional data set, the experimental results show that the feature selection method outperforms the other traditional methods.

  6. A Novel Approach for Automatic Machining Feature Recognition with Edge Blend Feature

    OpenAIRE

    Keong Chen Wong; Yusof Yusri

    2017-01-01

    This paper presents an algorithm for efficiently recognizing and determining the convexity of an edge blend feature. The algorithm first recognizes all of the edge blend features from the Boundary Representation of a part; then a series of convexity test have been run on the recognized edge blend features. The novelty of the presented algorithm lies in, instead of each recognized blend feature is suppressed as most of researchers did, the recognized blend features of this research are gone th...

  7. Electrical and gas sensing properties of novel cobalt(II), copper(II), manganese(III) phthalocyanines carrying ethyl 7-oxy-4,8-dimethylcoumarin-3-propanoate moieties

    Science.gov (United States)

    Köksoy, Baybars; Aygün, Meryem; Çapkin, Aylin; Dumludağ, Fatih; Bulut, Mustafa

    The synthesis of metallophthalocyanines (M = Co, Cu, Mn) bearing four ethyl 7-oxy-4,8-dimethylcoumarin-3-propanoate moieties was performed. These novel compounds were characterized by elemental analysis, 1H-NMR spectroscopy, FT-IR, UV-vis and mass spectral data. DC and AC electrical properties of the films of metallophthalocyanines were investigated in the temperature range of 295-523 K. AC measurements were performed in the frequency range of 40-105 Hz. Activation energy values of the films took place between 0.55 eV-0.93 eV. Impedance spectroscopy measurements revealed that bulk resistance decreases with increasing temperature, indicating semiconductor properties. DC conductivity results also supported this result. Their gas sensing properties were also investigated for the vapors of Volatile Organic Compounds (VOCs), n-butyl acetate (200-3200 ppm) and ammonia (7000-56000 ppm) between temperatures 25-100°C. Sensitivity and response times of the films for the tested vapors were reported. The results were found to be reversible and sensitive to the vapors of n-butyl acetate and ammonia. It was found that Mn(OAc)Pc showed better sensitivity than CoPc and CuPc for n-butyl acetate vapors at all measured vapor concentrations and temperatures. Mn(OAc)Pc also showed better sensitivity than CoPc and CuPc for ammonia vapors at 22°C. Co(II), Cu(II), Mn(III)OAc phthalocyanines bearing four ethyl 7-oxy-4,8-dimethyl-coumarin-3-propanoate moieties were prepared and characterized. DC and AC (40-105 Hz) electrical properties of the films of metallophthalocyanines were investigated in the temperature range of 295-523 K. Impedance spectroscopy measurements revealed that bulk resistance decreases with increasing temperature indicating semiconductor property. Their gas sensing properties were also investigated for the vapors of VOCs, n-butyl acetate (200-3200 ppm) and ammonia (7000-56000 ppm) between temperatures 25-100°C.

  8. A dansyl-rhodamine chemosensor for Fe(III) based on off-on FRET

    Science.gov (United States)

    Piao, Jingyu; Lv, Jia; Zhou, Xin; Zhao, Tong; Wu, Xue

    2014-07-01

    A novel fluorescent chemosensor bearing a rhodamine and a dansyl moiety was developed for highly selective detection of Fe3+ based on fluorescence resonance energy transfer (FRET) mechanism. Binding of Fe3+ to the chemosensor induced spirolactam ring opening in the rhodamine moiety and subsequent off-on FRET from the dansyl energy donor to the rhodamine energy acceptor due to the spectral overlap between the emission of the dansyl moiety and the absorption of the ring opened rhodamine moiety. Job's plot analysis indicated a 1:1 binding stoichiometry between the chemosensor and Fe3+. The association constant was estimated to be 2.72 × 103 M-1 according to the Benesi-Hildebrand method. With the feature of easy synthesis, simple structural skeleton and excellent sensing ability, the newly synthesized chemosensor provided the potential for applying as a highly selective fluorescent probe in complex samples containing various competitive metal ions and developing other metal ion chemosensors to fulfill various needs of biological and environmental field.

  9. Influence of galloyl moiety in interaction of epicatechin with bovine serum albumin: a spectroscopic and thermodynamic characterization.

    Directory of Open Access Journals (Sweden)

    Sandip Pal

    Full Text Available The health benefits stemming from green tea are well known, but the exact mechanism of its biological activity is not elucidated. Epicatechin (EC and epicatechin gallate (ECG are two dietary catechins ubiquitously present in green tea. Serum albumins functionally carry these catechins through the circulatory system and eliminate reactive oxygen species (ROS induced injury. In the present study ECG is observed to have higher antioxidant activity; which is attributed to the presence of galloyl moiety. The binding affinity of these catechins to bovine serum albumin (BSA will govern the efficacy of their biological activity. EC and ECG bind with BSA with binding constants 1.0 × 10(6 M(-1 and 6.6 × 10(7 M(-1, respectively. Changes in secondary structure of BSA on interaction with EC and ECG have been identified by circular dichroism (CD and Fourier transform infrared (FT-IR spectroscopy. Thermodynamic characterization reveals the binding process to be exothermic, spontaneous and entropy driven. Mixed binding forces (hydrophobic, electrostatic and hydrogen bonding exist between ECG and BSA. Binding site for EC is primarily site-II in sub-domain IIIA of BSA and for ECG; it is site-I in sub-domain IIA. ECG with its high antioxidant activity accompanied by high affinity for BSA could be a model in drug designing.

  10. A Gene Cluster for Biosynthesis of Mannosylerythritol Lipids Consisted of 4-O-β-D-Mannopyranosyl-(2R,3S-Erythritol as the Sugar Moiety in a Basidiomycetous Yeast Pseudozyma tsukubaensis.

    Directory of Open Access Journals (Sweden)

    Azusa Saika

    Full Text Available Mannosylerythritol lipids (MELs belong to the glycolipid biosurfactants and are produced by various fungi. The basidiomycetous yeast Pseudozyma tsukubaensis produces diastereomer type of MEL-B, which contains 4-O-β-D-mannopyranosyl-(2R,3S-erythritol (R-form as the sugar moiety. In this respect it differs from conventional type of MELs, which contain 4-O-β-D-mannopyranosyl-(2S,3R-erythritol (S-form as the sugar moiety. While the biosynthetic gene cluster for conventional type of MELs has been previously identified in Ustilago maydis and Pseudozyma antarctica, the genetic basis for MEL biosynthesis in P. tsukubaensis is unknown. Here, we identified a gene cluster involved in MEL biosynthesis in P. tsukubaensis. Among these genes, PtEMT1, which encodes erythritol/mannose transferase, had greater than 69% identity with homologs from strains in the genera Ustilago, Melanopsichium, Sporisorium and Pseudozyma. However, phylogenetic analysis placed PtEMT1p in a separate clade from the other proteins. To investigate the function of PtEMT1, we introduced the gene into a P. antarctica mutant strain, ΔPaEMT1, which lacks MEL biosynthesis ability owing to the deletion of PaEMT1. Using NMR spectroscopy, we identified the biosynthetic product as MEL-A with altered sugar conformation. These results indicate that PtEMT1p catalyzes the sugar conformation of MELs. This is the first report of a gene cluster for the biosynthesis of diastereomer type of MEL.

  11. Quantum mechanics models of the methanol dimer: OH⋯O hydrogen bonds of β-d-glucose moieties from crystallographic data.

    Science.gov (United States)

    Cintrón, Michael Santiago; Johnson, Glenn P; French, Alfred D

    2017-04-18

    The interaction of two methanol molecules, simplified models of carbohydrates and cellulose, was examined using a variety of quantum mechanics (QM) levels of theory. Energy plots for hydrogen bonding distance (H⋯O) and angle (OH⋯O) were constructed. All but two experimental structures were located in stabilized areas on the vacuum phase energy plots. Each of the 399 models was analyzed with Bader's atoms-in-molecules (AIM) theory, which showed a widespread ability by the dimer models to form OH⋯O hydrogen bonds that have bond paths and Bond Critical Points. Continuum solvation calculations suggest that a portion of the energy-stabilized structures could occur in the presence of water. A survey of the Cambridge Structural Database (CSD) for all donor-acceptor interactions in β-D-glucose moieties examined the similarities and differences among the hydroxyl groups and acetal oxygen atoms that participate in hydrogen bonds. Comparable behavior was observed for the O2H, O3H, O4H, and O6H hydroxyls, acting either as acceptors or donors. Ring O atoms showed distinct hydrogen bonding behavior that favored mid-length hydrogen bonds. Published by Elsevier Ltd.

  12. Synthesis of [3,5-14C]trachelanthamidine and [5-3H]isoretronecanol and their incorporation into the retronecine moiety of riddelliine in Senecio riddellii

    International Nuclear Information System (INIS)

    Leete, E.; Rana, J.

    1986-01-01

    (+/-)-[3,5- 14 C]Trachelanthamidine and (+/-)-[5- 3 H]isoretronecanol, which are diastereomers, were prepared from potassium [ 14 C]cyanide and [5- 3 H]proline, respectively. These compounds and [1,4- 14 C]putrescine were administered to Senecio riddellii plants resulting in the formation of labeled riddelliine, in which almost all the radioactivity was located in its retronecine moiety. The activity of the beta-alanine obtained by degradation of the retronecine was consistent with specific labeling of this pyrrolizidine base at the expected positions. The extremely high absolute incorporation (15.1, 22.1%) of trachelanthamidine into riddelliine strongly favors this 1-hydroxymethylpyrrolizidine as the one on the main biosynthetic pathway to retronecine. The lower incorporation (0.75%) of isoretronecanol may represent a minor or aberrant pathway to retronecine

  13. Liquid crystalline polymers IX Main chain thermotropic poly (azomethine – ethers containing thiazole moiety linked with polymethylene spacers

    Directory of Open Access Journals (Sweden)

    2007-04-01

    Full Text Available A new homologous series of thermally stable thermotropic liquid crystalline poly(azomethine-ethers based on thiazole moiety were synthesized by solution polycondensation of 4,4`-diformyl-α,ω-diphenoxyalkanes, I–IV or 4,4`-diformyl-2,2`-dimethoxy-α,ω-diphenoxyalkanes V–VIII with the new bis(2-aminothiazole monomer X. A model compound XI was synthesized from X with benzaldehyde and characterized by elemental and spectral analyses. The inherent viscosities of the resulting polymers were in the range 0.43–1.34 dI/g. All the poly(azomethine-ethers were insoluble in common organic solvents but dissolved completely in concentrated H2SO4 and formic acid. The mesomorphic properties of these polymers were studied as a function of the diphenoxyalkane space length. Their thermotropic liquid crystalline properties were examined by DSC and optical polarizing microscopy and demonstrated that the resulting polymers form nematic mesophases over wide temperature ranges. The thermogravimetric analyses of those polymers were evaluated by TGA and DSC measurements and correlated to their structural units. X-ray analysis showed that polymers having some degree of crystallinity in the region 2θ = 5–60°. In addition, the morphological properties of selected examples were tested by scanning electron microscopy.

  14. Unsupervised Feature Subset Selection

    DEFF Research Database (Denmark)

    Søndberg-Madsen, Nicolaj; Thomsen, C.; Pena, Jose

    2003-01-01

    This paper studies filter and hybrid filter-wrapper feature subset selection for unsupervised learning (data clustering). We constrain the search for the best feature subset by scoring the dependence of every feature on the rest of the features, conjecturing that these scores discriminate some ir...... irrelevant features. We report experimental results on artificial and real data for unsupervised learning of naive Bayes models. Both the filter and hybrid approaches perform satisfactorily....

  15. When do letter features migrate? A boundary condition for feature-integration theory.

    Science.gov (United States)

    Butler, B E; Mewhort, D J; Browse, R A

    1991-01-01

    Feature-integration theory postulates that a lapse of attention will allow letter features to change position and to recombine as illusory conjunctions (Treisman & Paterson, 1984). To study such errors, we used a set of uppercase letters known to yield illusory conjunctions in each of three tasks. The first, a bar-probe task, showed whole-character mislocations but not errors based on feature migration and recombination. The second, a two-alternative forced-choice detection task, allowed subjects to focus on the presence or absence of subletter features and showed illusory conjunctions based on feature migration and recombination. The third was also a two-alternative forced-choice detection task, but we manipulated the subjects' knowledge of the shape of the stimuli: In the case-certain condition, the stimuli were always in uppercase, but in the case-uncertain condition, the stimuli could appear in either upper- or lowercase. Subjects in the case-certain condition produced illusory conjunctions based on feature recombination, whereas subjects in the case-uncertain condition did not. The results suggest that when subjects can view the stimuli as feature groups, letter features regroup as illusory conjunctions; when subjects encode the stimuli as letters, whole items may be mislocated, but subletter features are not. Thus, illusory conjunctions reflect the subject's processing strategy, rather than the architecture of the visual system.

  16. Featureous: an Integrated Approach to Location, Analysis and Modularization of Features in Java Applications

    DEFF Research Database (Denmark)

    Olszak, Andrzej

    , it is essential that features are properly modularized within the structural organization of software systems. Nevertheless, in many object-oriented applications, features are not represented explicitly. Consequently, features typically end up scattered and tangled over multiple source code units......, such as architectural layers, packages and classes. This lack of modularization is known to make application features difficult to locate, to comprehend and to modify in isolation from one another. To overcome these problems, this thesis proposes Featureous, a novel approach to location, analysis and modularization...... quantitative and qualitative results suggest that Featureous succeeds at efficiently locating features in unfamiliar codebases, at aiding feature-oriented comprehension and modification, and at improving modularization of features using Java packages....

  17. Innovations in individual feature history management - The significance of feature-based temporal model

    Science.gov (United States)

    Choi, J.; Seong, J.C.; Kim, B.; Usery, E.L.

    2008-01-01

    A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO's temporal schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO's temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query performance on feature history by removing topological comparison during query process. Further, a prototype system has been developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure. ?? Springer Science+Business Media, LLC 2007.

  18. Dependency Parsing with Transformed Feature

    Directory of Open Access Journals (Sweden)

    Fuxiang Wu

    2017-01-01

    Full Text Available Dependency parsing is an important subtask of natural language processing. In this paper, we propose an embedding feature transforming method for graph-based parsing, transform-based parsing, which directly utilizes the inner similarity of the features to extract information from all feature strings including the un-indexed strings and alleviate the feature sparse problem. The model transforms the extracted features to transformed features via applying a feature weight matrix, which consists of similarities between the feature strings. Since the matrix is usually rank-deficient because of similar feature strings, it would influence the strength of constraints. However, it is proven that the duplicate transformed features do not degrade the optimization algorithm: the margin infused relaxed algorithm. Moreover, this problem can be alleviated by reducing the number of the nearest transformed features of a feature. In addition, to further improve the parsing accuracy, a fusion parser is introduced to integrate transformed and original features. Our experiments verify that both transform-based and fusion parser improve the parsing accuracy compared to the corresponding feature-based parser.

  19. The feature-weighted receptive field: an interpretable encoding model for complex feature spaces.

    Science.gov (United States)

    St-Yves, Ghislain; Naselaris, Thomas

    2017-06-20

    We introduce the feature-weighted receptive field (fwRF), an encoding model designed to balance expressiveness, interpretability and scalability. The fwRF is organized around the notion of a feature map-a transformation of visual stimuli into visual features that preserves the topology of visual space (but not necessarily the native resolution of the stimulus). The key assumption of the fwRF model is that activity in each voxel encodes variation in a spatially localized region across multiple feature maps. This region is fixed for all feature maps; however, the contribution of each feature map to voxel activity is weighted. Thus, the model has two separable sets of parameters: "where" parameters that characterize the location and extent of pooling over visual features, and "what" parameters that characterize tuning to visual features. The "where" parameters are analogous to classical receptive fields, while "what" parameters are analogous to classical tuning functions. By treating these as separable parameters, the fwRF model complexity is independent of the resolution of the underlying feature maps. This makes it possible to estimate models with thousands of high-resolution feature maps from relatively small amounts of data. Once a fwRF model has been estimated from data, spatial pooling and feature tuning can be read-off directly with no (or very little) additional post-processing or in-silico experimentation. We describe an optimization algorithm for estimating fwRF models from data acquired during standard visual neuroimaging experiments. We then demonstrate the model's application to two distinct sets of features: Gabor wavelets and features supplied by a deep convolutional neural network. We show that when Gabor feature maps are used, the fwRF model recovers receptive fields and spatial frequency tuning functions consistent with known organizational principles of the visual cortex. We also show that a fwRF model can be used to regress entire deep

  20. Language Features and Culture Features on Short Message

    Institute of Scientific and Technical Information of China (English)

    王佳

    2013-01-01

    Mobile phone is regarded as“the fifth media”after newspaper,radio,TV and the Internet.The mobile phone short message further highlights the importance of written signs in communication.“The thumb revolution”is eagerly anticipating one kind of trend by the hand replace of mouth,sound substitute for the quiet around us. My paper will analyze the language features and the culture features of mobile phone short messages which are written in Chinese and English.

  1. Syntheses and characterization of liposome-incorporated adamantyl aminoguanidines.

    Science.gov (United States)

    Šekutor, Marina; Štimac, Adela; Mlinarić-Majerski, Kata; Frkanec, Ruža

    2014-08-21

    A series of mono and bis-aminoguanidinium adamantane derivatives has been synthesized and incorporated into liposomes. They combine two biomedically significant molecules, the adamantane moiety and the guanidinium group. The adamantane moiety possesses the membrane compatible features while the cationic guanidinium subunit was recognized as a favourable structural feature for binding to complementary molecules comprising phosphate groups. The liposome formulations of adamantyl aminoguanidines were characterized and it was shown that the entrapment efficiency of the examined compounds is significant. In addition, it was demonstrated that liposomes with incorporated adamantyl aminoguanidines effectively recognized the complementary liposomes via the phosphate group. These results indicate that adamantane derivatives bearing guanidinium groups might be versatile tools for biomedical application, from studies of molecular recognition processes to usage in drug formulation and cell targeting.

  2. Muscle-type nicotinic receptor blockade by diethylamine, the hydrophilic moiety of lidocaine

    Directory of Open Access Journals (Sweden)

    Armando eAlberola-Die

    2016-02-01

    Full Text Available Lidocaine bears in its structure both an aromatic ring and a terminal amine, which can be protonated at physiological pH, linked by an amide group. Since lidocaine causes multiple inhibitory actions on nicotinic acetylcholine receptors (nAChRs, this work was aimed to determine the inhibitory effects of diethylamine (DEA, a small molecule resembling the hydrophilic moiety of lidocaine, on Torpedo marmorata nAChRs microtransplanted to Xenopus oocytes. Similarly to lidocaine, DEA reversibly blocked acetylcholine-elicited currents (IACh in a dose-dependent manner (IC50 close to 70 μM, but unlike lidocaine, DEA did not affect IACh desensitization. IACh inhibition by DEA was more pronounced at negative potentials, suggesting an open-channel blockade of nAChRs, although roughly 30% inhibition persisted at positive potentials, indicating additional binding sites outside the pore. DEA block of nAChRs in the resting state (closed channel was confirmed by the enhanced IACh inhibition when pre-applying DEA before its co-application with ACh, as compared with solely DEA and ACh co-application. Virtual docking assays provide a plausible explanation to the experimental observations in terms of the involvement of different sets of drug binding sites. So, at the nAChR transmembrane (TM domain, DEA and lidocaine shared binding sites within the channel pore, giving support to their open-channel blockade; besides, lidocaine, but not DEA, interacted with residues at cavities among the M1, M2, M3 and M4 segments of each subunit and also at intersubunit crevices. At the extracellular (EC domain, DEA and lidocaine binding sites were broadly distributed, which aids to explain the closed channel blockade observed. Interestingly, some DEA clusters were located at the α-γ interphase of the EC domain, in a cavity near the orthosteric binding site pocket; by contrast, lidocaine contacted with all α-subunit loops conforming the ACh binding site, both in α-γ and

  3. Feature selection for splice site prediction: A new method using EDA-based feature ranking

    Directory of Open Access Journals (Sweden)

    Rouzé Pierre

    2004-05-01

    Full Text Available Abstract Background The identification of relevant biological features in large and complex datasets is an important step towards gaining insight in the processes underlying the data. Other advantages of feature selection include the ability of the classification system to attain good or even better solutions using a restricted subset of features, and a faster classification. Thus, robust methods for fast feature selection are of key importance in extracting knowledge from complex biological data. Results In this paper we present a novel method for feature subset selection applied to splice site prediction, based on estimation of distribution algorithms, a more general framework of genetic algorithms. From the estimated distribution of the algorithm, a feature ranking is derived. Afterwards this ranking is used to iteratively discard features. We apply this technique to the problem of splice site prediction, and show how it can be used to gain insight into the underlying biological process of splicing. Conclusion We show that this technique proves to be more robust than the traditional use of estimation of distribution algorithms for feature selection: instead of returning a single best subset of features (as they normally do this method provides a dynamical view of the feature selection process, like the traditional sequential wrapper methods. However, the method is faster than the traditional techniques, and scales better to datasets described by a large number of features.

  4. Simultaneous Channel and Feature Selection of Fused EEG Features Based on Sparse Group Lasso

    Directory of Open Access Journals (Sweden)

    Jin-Jia Wang

    2015-01-01

    Full Text Available Feature extraction and classification of EEG signals are core parts of brain computer interfaces (BCIs. Due to the high dimension of the EEG feature vector, an effective feature selection algorithm has become an integral part of research studies. In this paper, we present a new method based on a wrapped Sparse Group Lasso for channel and feature selection of fused EEG signals. The high-dimensional fused features are firstly obtained, which include the power spectrum, time-domain statistics, AR model, and the wavelet coefficient features extracted from the preprocessed EEG signals. The wrapped channel and feature selection method is then applied, which uses the logistical regression model with Sparse Group Lasso penalized function. The model is fitted on the training data, and parameter estimation is obtained by modified blockwise coordinate descent and coordinate gradient descent method. The best parameters and feature subset are selected by using a 10-fold cross-validation. Finally, the test data is classified using the trained model. Compared with existing channel and feature selection methods, results show that the proposed method is more suitable, more stable, and faster for high-dimensional feature fusion. It can simultaneously achieve channel and feature selection with a lower error rate. The test accuracy on the data used from international BCI Competition IV reached 84.72%.

  5. Minimalism in fabrication of self-organized nanogels holding both anti-cancer drug and targeting moiety.

    Science.gov (United States)

    Kim, Sungwon; Park, Kyong Mi; Ko, Jin Young; Kwon, Ick Chan; Cho, Hyeon Geun; Kang, Dongmin; Yu, In Tag; Kim, Kwangmeyung; Na, Kun

    2008-05-01

    Recent researches to develop nano-carrier systems in anti-cancer drug delivery have focused on more complicated design to improve therapeutic efficacy and to reduce side effects. Although such efforts have great impact to biomedical science and engineering, the complexity has been a huddle because of clinical and economic problems. In order to overcome the problems, a simplest strategy to fabricate nano-carriers to deliver doxorubicin (DOX) was proposed in the present study. Two significant subjects (i) formation of nanoparticles loading and releasing DOX and (ii) binding specificity of them to cells, were examined. Folic acid (FA) was directly coupled with pullulan (Pul) backbone by ester linkage (FA/Pul conjugate) and the degree of substitution (DS) was varied, which were confirmed by 1H NMR and UV spectrophotometry. Light scattering results revealed that the nanogels possessed two major size distributions around 70 and 270 nm in an aqueous solution. Their critical aggregation concentrations (CACs) were less than 10 microg/mL, which are lower than general critical micelle concentrations (CMCs) of low-molecular-weight surfactants. Transmission electron microscopy (TEM) images showed well-dispersed nanogel morphology in a dried state. Depending on the DS, the nanogels showed different DOX-loading and releasing profiles. The DOX release rate from FA8/Pul (with the highest DS) for 24h was slower than that from FA4/or FA6/Pul, indicating that the FA worked as a hydrophobic moiety for drug holding. Cellular uptake of the nanogels (KB cells) was also monitored by confocal microscopy. All nanogels were internalized regardless of the DS of FA. Based on the results, the objectives of this study, to suggest a new method overcoming the complications in the drug carrier design, were successfully verified.

  6. Coding of visual object features and feature conjunctions in the human brain.

    Science.gov (United States)

    Martinovic, Jasna; Gruber, Thomas; Müller, Matthias M

    2008-01-01

    Object recognition is achieved through neural mechanisms reliant on the activity of distributed coordinated neural assemblies. In the initial steps of this process, an object's features are thought to be coded very rapidly in distinct neural assemblies. These features play different functional roles in the recognition process--while colour facilitates recognition, additional contours and edges delay it. Here, we selectively varied the amount and role of object features in an entry-level categorization paradigm and related them to the electrical activity of the human brain. We found that early synchronizations (approx. 100 ms) increased quantitatively when more image features had to be coded, without reflecting their qualitative contribution to the recognition process. Later activity (approx. 200-400 ms) was modulated by the representational role of object features. These findings demonstrate that although early synchronizations may be sufficient for relatively crude discrimination of objects in visual scenes, they cannot support entry-level categorization. This was subserved by later processes of object model selection, which utilized the representational value of object features such as colour or edges to select the appropriate model and achieve identification.

  7. Synthesis and Antimicrobial Evaluation of Some Novel Thiazole, Pyridone, Pyrazole, Chromene, Hydrazone Derivatives Bearing a Biologically Active Sulfonamide Moiety

    Science.gov (United States)

    Darwish, Elham S.; Abdel Fattah, Azza M.; Attaby, Fawzy A.; Al-Shayea, Oqba N.

    2014-01-01

    This study aimed for the synthesis of new heterocyclic compounds incorporating sulfamoyl moiety suitable for use as antimicrobial agents via a versatile, readily accessible N-[4-(aminosulfonyl)phenyl]-2-cyanoacetamide (3). The 2-pyridone derivatives were obtained via reaction of cyanoacetamide with acetylacetone or arylidenes malononitrile. Cycloaddition reaction of cyanoacetamide with salicyaldehyde furnished chromene derivatives. Diazotization of 3 with the desired diazonium chloride gave the hydrazone derivatives 13a–e. Also, the reactivity of the hydrazone towards hydrazine hydrate to give Pyrazole derivatives was studied. In addition, treatment of 3 with elemental sulfur and phenyl isothiocyanate or malononitrile furnished thiazole and thiophene derivatives respectively. Reaction of 3 with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt 17 which reacted in situ with 3-(2-bromoacetyl)-2H-chromen-2-one and methyl iodide afforded the thiazole and ketene N,S-acetal derivatives respectively. Finally, reaction of 3 with carbon disulfide and 1,3-dibromopropane afforded the N-[4-(aminosulfonyl) phenyl]-2-cyano-2-(1,3-dithian-2-ylidene)acetamide product 22. All newly synthesized compounds were elucidated by considering the data of both elemental and spectral analysis. The compounds were evaluated for both their in vitro antibacterial and antifungal activities and showed promising results. PMID:24445259

  8. Synthesis and Antimicrobial Evaluation of Some Novel Thiazole, Pyridone, Pyrazole, Chromene, Hydrazone Derivatives Bearing a Biologically Active Sulfonamide Moiety

    Directory of Open Access Journals (Sweden)

    Elham S. Darwish

    2014-01-01

    Full Text Available This study aimed for the synthesis of new heterocyclic compounds incorporating sulfamoyl moiety suitable for use as antimicrobial agents via a versatile, readily accessible N-[4-(aminosulfonylphenyl]-2-cyanoacetamide (3. The 2-pyridone derivatives were obtained via reaction of cyanoacetamide with acetylacetone or arylidenes malononitrile. Cycloaddition reaction of cyanoacetamide with salicyaldehyde furnished chromene derivatives. Diazotization of 3 with the desired diazonium chloride gave the hydrazone derivatives 13a–e. Also, the reactivity of the hydrazone towards hydrazine hydrate to give Pyrazole derivatives was studied. In addition, treatment of 3 with elemental sulfur and phenyl isothiocyanate or malononitrile furnished thiazole and thiophene derivatives respectively. Reaction of 3 with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt 17 which reacted in situ with 3-(2-bromoacetyl-2H-chromen-2-one and methyl iodide afforded the thiazole and ketene N,S-acetal derivatives respectively. Finally, reaction of 3 with carbon disulfide and 1,3-dibromopropane afforded the N-[4-(aminosulfonyl phenyl]-2-cyano-2-(1,3-dithian-2-ylideneacetamide product 22. All newly synthesized compounds were elucidated by considering the data of both elemental and spectral analysis. The compounds were evaluated for both their in vitro antibacterial and antifungal activities and showed promising results.

  9. Levels of Urinary Trypsin Inhibitor and Structure of Its Chondroitin Sulphate Moiety in Type 1 and Type 2 Diabetes

    Science.gov (United States)

    Ucciferri, Nadia; Idini, Michela; De Muro, Pierina

    2018-01-01

    Background Diabetes mellitus is a global health problem representing the fifth leading cause of mortality and a major risk factor for cardiovascular diseases. In the last years, we reported an association among urinary trypsin inhibitor (UTI), a small proteoglycan that plays pleiotropic roles in many inflammatory processes, and both type 1 and 2 diabetes and developed a method for its direct quantitation and structural characterization. Methods Urine from 39 patients affected by type 1 diabetes, 32 patients with type 2 diabetes, and 52 controls were analysed. UTI was separated from the main glycosaminoglycans physiologically present in urine by anion exchange chromatography, treated for chondroitin sulphate (CS) chain complete depolymerisation, and analysed for both UTI content and CS structure. UTI identification was performed by nano-LC-MS/MS analysis. Results We evidenced increased UTI levels, as well as reduced sulphation of its CS moiety in association with diabetes, regardless of both age and medium-term glycaemic control. Furthermore, no association between UTI and albumin excretion rate was found. Conclusions Evidences suggest that UTI levels are not directly correlated with renal function or, otherwise, that they may increase before the onset of renal impairment in diabetes, representing a potential marker for the underlying inflammatory condition. PMID:29541644

  10. An object-oriented feature-based design system face-based detection of feature interactions

    International Nuclear Information System (INIS)

    Ariffin Abdul Razak

    1999-01-01

    This paper presents an object-oriented, feature-based design system which supports the integration of design and manufacture by ensuring that part descriptions fully account for any feature interactions. Manufacturing information is extracted from the feature descriptions in the form of volumes and Tool Access Directions, TADs. When features interact, both volumes and TADs are updated. This methodology has been demonstrated by developing a prototype system in which ACIS attributes are used to record feature information within the data structure of the solid model. The system implemented in the C++ programming language and embedded in a menu-driven X-windows user interface to the ACIS 3D Toolkit. (author)

  11. Feature-Based Retinal Image Registration Using D-Saddle Feature

    Directory of Open Access Journals (Sweden)

    Roziana Ramli

    2017-01-01

    Full Text Available Retinal image registration is important to assist diagnosis and monitor retinal diseases, such as diabetic retinopathy and glaucoma. However, registering retinal images for various registration applications requires the detection and distribution of feature points on the low-quality region that consists of vessels of varying contrast and sizes. A recent feature detector known as Saddle detects feature points on vessels that are poorly distributed and densely positioned on strong contrast vessels. Therefore, we propose a multiresolution difference of Gaussian pyramid with Saddle detector (D-Saddle to detect feature points on the low-quality region that consists of vessels with varying contrast and sizes. D-Saddle is tested on Fundus Image Registration (FIRE Dataset that consists of 134 retinal image pairs. Experimental results show that D-Saddle successfully registered 43% of retinal image pairs with average registration accuracy of 2.329 pixels while a lower success rate is observed in other four state-of-the-art retinal image registration methods GDB-ICP (28%, Harris-PIIFD (4%, H-M (16%, and Saddle (16%. Furthermore, the registration accuracy of D-Saddle has the weakest correlation (Spearman with the intensity uniformity metric among all methods. Finally, the paired t-test shows that D-Saddle significantly improved the overall registration accuracy of the original Saddle.

  12. A dansyl-rhodamine chemosensor for Fe(III) based on off-on FRET.

    Science.gov (United States)

    Piao, Jingyu; Lv, Jia; Zhou, Xin; Zhao, Tong; Wu, Xue

    2014-07-15

    A novel fluorescent chemosensor bearing a rhodamine and a dansyl moiety was developed for highly selective detection of Fe(3+) based on fluorescence resonance energy transfer (FRET) mechanism. Binding of Fe(3+) to the chemosensor induced spirolactam ring opening in the rhodamine moiety and subsequent off-on FRET from the dansyl energy donor to the rhodamine energy acceptor due to the spectral overlap between the emission of the dansyl moiety and the absorption of the ring opened rhodamine moiety. Job's plot analysis indicated a 1:1 binding stoichiometry between the chemosensor and Fe(3+). The association constant was estimated to be 2.72×10(3) M(-1) according to the Benesi-Hildebrand method. With the feature of easy synthesis, simple structural skeleton and excellent sensing ability, the newly synthesized chemosensor provided the potential for applying as a highly selective fluorescent probe in complex samples containing various competitive metal ions and developing other metal ion chemosensors to fulfill various needs of biological and environmental field. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Screening for Plant Features

    NARCIS (Netherlands)

    Heijden, van der G.W.A.M.; Polder, G.

    2015-01-01

    In this chapter, an overview of different plant features is given, from (sub)cellular to canopy level. A myriad of methods is available to measure these features using image analysis, and often, multiple methods can be used to measure the same feature. Several criteria are listed for choosing a

  14. Synthesis and Biological Activity of Substituted Urea and Thiourea Derivatives Containing 1,2,4-Triazole Moieties

    Directory of Open Access Journals (Sweden)

    David E. Wedge

    2013-03-01

    Full Text Available A series of novel thiourea and urea derivatives containing 1,2,4-triazole moieties were synthesized and evaluated for their antifungal and larvicidal activity. Triazole derivatives 3a–e and 4a–e were synthesized by reacting thiocarbohydrazide with thiourea and urea compounds 1a–e and 2a–e, respectively, in a 130–140 °C oil bath. The proposed structures of all the synthesized compounds were confirmed using elemental analysis, UV, IR, 1H-NMR and mass spectroscopy. All compounds were evaluated for antifungal activity against plant pathogens, larvicidal and biting deterrent activity against the mosquito Aedes aegypti L. and in vitro cytotoxicity and anti-inflammatory activity against some human cell lines. Phomopis species were the most sensitive fungi to these compounds. Compounds 1b, 1c, 3a and 4e demonstrated selectively good activity against Phomopis obscurans and only 1b and 4e showed a similar level of activity against P. viticola. Compound 3d, with a LD50 value of 67.9 ppm, followed by 1c (LD50 = 118.8 ppm and 3e (LD50 = 165.6 ppm, showed the highest toxicity against Aedes aegypti larvae. Four of these compounds showed biting deterrent activity greater than solvent control, with the highest activity being seen for 1c, with a proportion not biting (PNB value of 0.75, followed by 1e, 2b and 1a. No cytotoxicity was observed against the tested human cancer cell lines. No anti-inflammatory activity was observed against NF-kB dependent transcription induced by phorbol myristate acetate (PMA in human chondrosarcoma cells.

  15. Decontaminate feature for tracking: adaptive tracking via evolutionary feature subset

    Science.gov (United States)

    Liu, Qiaoyuan; Wang, Yuru; Yin, Minghao; Ren, Jinchang; Li, Ruizhi

    2017-11-01

    Although various visual tracking algorithms have been proposed in the last 2-3 decades, it remains a challenging problem for effective tracking with fast motion, deformation, occlusion, etc. Under complex tracking conditions, most tracking models are not discriminative and adaptive enough. When the combined feature vectors are inputted to the visual models, this may lead to redundancy causing low efficiency and ambiguity causing poor performance. An effective tracking algorithm is proposed to decontaminate features for each video sequence adaptively, where the visual modeling is treated as an optimization problem from the perspective of evolution. Every feature vector is compared to a biological individual and then decontaminated via classical evolutionary algorithms. With the optimized subsets of features, the "curse of dimensionality" has been avoided while the accuracy of the visual model has been improved. The proposed algorithm has been tested on several publicly available datasets with various tracking challenges and benchmarked with a number of state-of-the-art approaches. The comprehensive experiments have demonstrated the efficacy of the proposed methodology.

  16. Synthesis of (3,5-/sup 14/C)trachelanthamidine and (5-/sup 3/H)isoretronecanol and their incorporation into the retronecine moiety of riddelliine in Senecio riddellii

    Energy Technology Data Exchange (ETDEWEB)

    Leete, E.; Rana, J.

    1986-09-01

    (+/-)-(3,5-/sup 14/C)Trachelanthamidine and (+/-)-(5-/sup 3/H)isoretronecanol, which are diastereomers, were prepared from potassium (/sup 14/C)cyanide and (5-/sup 3/H)proline, respectively. These compounds and (1,4-/sup 14/C)putrescine were administered to Senecio riddellii plants resulting in the formation of labeled riddelliine, in which almost all the radioactivity was located in its retronecine moiety. The activity of the beta-alanine obtained by degradation of the retronecine was consistent with specific labeling of this pyrrolizidine base at the expected positions. The extremely high absolute incorporation (15.1, 22.1%) of trachelanthamidine into riddelliine strongly favors this 1-hydroxymethylpyrrolizidine as the one on the main biosynthetic pathway to retronecine. The lower incorporation (0.75%) of isoretronecanol may represent a minor or aberrant pathway to retronecine.

  17. Dissociation between Features and Feature Relations in Infant Memory: Effects of Memory Load.

    Science.gov (United States)

    Bhatt, Ramesh S.; Rovee-Collier, Carolyn

    1997-01-01

    Four experiments examined effects of the number of features and feature relations on learning and long-term memory in 3-month olds. Findings suggested that memory load size selectively constrained infants' long-term memory for relational information, suggesting that in infants, features and relations are psychologically distinct and that memory…

  18. Depth estimation of features in video frames with improved feature matching technique using Kinect sensor

    Science.gov (United States)

    Sharma, Kajal; Moon, Inkyu; Kim, Sung Gaun

    2012-10-01

    Estimating depth has long been a major issue in the field of computer vision and robotics. The Kinect sensor's active sensing strategy provides high-frame-rate depth maps and can recognize user gestures and human pose. This paper presents a technique to estimate the depth of features extracted from video frames, along with an improved feature-matching method. In this paper, we used the Kinect camera developed by Microsoft, which captured color and depth images for further processing. Feature detection and selection is an important task for robot navigation. Many feature-matching techniques have been proposed earlier, and this paper proposes an improved feature matching between successive video frames with the use of neural network methodology in order to reduce the computation time of feature matching. The features extracted are invariant to image scale and rotation, and different experiments were conducted to evaluate the performance of feature matching between successive video frames. The extracted features are assigned distance based on the Kinect technology that can be used by the robot in order to determine the path of navigation, along with obstacle detection applications.

  19. Doubly sparse factor models for unifying feature transformation and feature selection

    International Nuclear Information System (INIS)

    Katahira, Kentaro; Okanoya, Kazuo; Okada, Masato; Matsumoto, Narihisa; Sugase-Miyamoto, Yasuko

    2010-01-01

    A number of unsupervised learning methods for high-dimensional data are largely divided into two groups based on their procedures, i.e., (1) feature selection, which discards irrelevant dimensions of the data, and (2) feature transformation, which constructs new variables by transforming and mixing over all dimensions. We propose a method that both selects and transforms features in a common Bayesian inference procedure. Our method imposes a doubly automatic relevance determination (ARD) prior on the factor loading matrix. We propose a variational Bayesian inference for our model and demonstrate the performance of our method on both synthetic and real data.

  20. Doubly sparse factor models for unifying feature transformation and feature selection

    Energy Technology Data Exchange (ETDEWEB)

    Katahira, Kentaro; Okanoya, Kazuo; Okada, Masato [ERATO, Okanoya Emotional Information Project, Japan Science Technology Agency, Saitama (Japan); Matsumoto, Narihisa; Sugase-Miyamoto, Yasuko, E-mail: okada@k.u-tokyo.ac.j [Human Technology Research Institute, National Institute of Advanced Industrial Science and Technology, Ibaraki (Japan)

    2010-06-01

    A number of unsupervised learning methods for high-dimensional data are largely divided into two groups based on their procedures, i.e., (1) feature selection, which discards irrelevant dimensions of the data, and (2) feature transformation, which constructs new variables by transforming and mixing over all dimensions. We propose a method that both selects and transforms features in a common Bayesian inference procedure. Our method imposes a doubly automatic relevance determination (ARD) prior on the factor loading matrix. We propose a variational Bayesian inference for our model and demonstrate the performance of our method on both synthetic and real data.

  1. Feature Import Vector Machine: A General Classifier with Flexible Feature Selection.

    Science.gov (United States)

    Ghosh, Samiran; Wang, Yazhen

    2015-02-01

    The support vector machine (SVM) and other reproducing kernel Hilbert space (RKHS) based classifier systems are drawing much attention recently due to its robustness and generalization capability. General theme here is to construct classifiers based on the training data in a high dimensional space by using all available dimensions. The SVM achieves huge data compression by selecting only few observations which lie close to the boundary of the classifier function. However when the number of observations are not very large (small n ) but the number of dimensions/features are large (large p ), then it is not necessary that all available features are of equal importance in the classification context. Possible selection of an useful fraction of the available features may result in huge data compression. In this paper we propose an algorithmic approach by means of which such an optimal set of features could be selected. In short, we reverse the traditional sequential observation selection strategy of SVM to that of sequential feature selection. To achieve this we have modified the solution proposed by Zhu and Hastie (2005) in the context of import vector machine (IVM), to select an optimal sub-dimensional model to build the final classifier with sufficient accuracy.

  2. Internal versus external features in triggering the brain waveforms for conjunction and feature faces in recognition.

    Science.gov (United States)

    Nie, Aiqing; Jiang, Jingguo; Fu, Qiao

    2014-08-20

    Previous research has found that conjunction faces (whose internal features, e.g. eyes, nose, and mouth, and external features, e.g. hairstyle and ears, are from separate studied faces) and feature faces (partial features of these are studied) can produce higher false alarms than both old and new faces (i.e. those that are exactly the same as the studied faces and those that have not been previously presented) in recognition. The event-related potentials (ERPs) that relate to conjunction and feature faces at recognition, however, have not been described as yet; in addition, the contributions of different facial features toward ERPs have not been differentiated. To address these issues, the present study compared the ERPs elicited by old faces, conjunction faces (the internal and the external features were from two studied faces), old internal feature faces (whose internal features were studied), and old external feature faces (whose external features were studied) with those of new faces separately. The results showed that old faces not only elicited an early familiarity-related FN400, but a more anterior distributed late old/new effect that reflected recollection. Conjunction faces evoked similar late brain waveforms as old internal feature faces, but not to old external feature faces. These results suggest that, at recognition, old faces hold higher familiarity than compound faces in the profiles of ERPs and internal facial features are more crucial than external ones in triggering the brain waveforms that are characterized as reflecting the result of familiarity.

  3. Influence of different amino substituents in position 1 and 4 on spectroscopic and acid base properties of 9,10-anthraquinone moiety.

    Science.gov (United States)

    Wcisło, Anna; Niedziałkowski, Paweł; Wnuk, Elżbieta; Zarzeczańska, Dorota; Ossowski, Tadeusz

    2013-05-01

    A series of novel 1-amino and 1,4-diamino-9,10-anthraquinones, substituted with different alkyl groups, were synthesized as the result of alkylation with amino substituents. All the obtained aminoanthraquinone derivatives were characterized by NMR, IR spectroscopy and mass spectrometry. The spectroscopic properties of these compounds were determined by using UV-Vis spectroscopy in acetonitrile, and in the mixture of acetonitrile and methanol at different pH ranges. The effects of various substituents present in the newly developed anthraquinone derivatives and their ability to form hydrogen bonds between the carbonyl oxygen atom of anthraquinone moiety and nitrogen atom of N-H group in 1-aminoanthraquinone (1-AAQ) and 1,4-diaminoanthraquinone (1,4-DAAQ) were studied. Additionally, the effects of hydrogen bond formation between O-H group in hydroxyethylamino substituent and the carbonyl oxygen atom of anthraquinone were investigated. The spectroscopic behavior of the studied derivatives strongly depended on the solvent-solute interactions and the nature of solvent. The values of pKa for the new anthraquinones were determined by the combined potentiometric and spectrophotometric titration methods. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Design, synthesis and evaluation of novel cinnamic acid derivatives bearing N-benzyl pyridinium moiety as multifunctional cholinesterase inhibitors for Alzheimer's disease.

    Science.gov (United States)

    Lan, Jin-Shuai; Hou, Jian-Wei; Liu, Yun; Ding, Yue; Zhang, Yong; Li, Ling; Zhang, Tong

    2017-12-01

    A novel family of cinnamic acid derivatives has been developed to be multifunctional cholinesterase inhibitors against AD by fusing N-benzyl pyridinium moiety and different substituted cinnamic acids. In vitro studies showed that most compounds were endowed with a noteworthy ability to inhibit cholinesterase, self-induced Aβ (1-42) aggregation, and to chelate metal ions. Especially, compound 5l showed potent cholinesterase inhibitory activity (IC 50 , 12.1 nM for eeAChE, 8.6 nM for hAChE, 2.6 μM for eqBuChE and 4.4 μM for hBuChE) and the highest selectivity toward AChE over BuChE. It also showed good inhibition of Aβ (1-42) aggregation (64.7% at 20 μM) and good neuroprotection on PC12 cells against amyloid-induced cell toxicity. Finally, compound 5l could penetrate the BBB, as forecasted by the PAMPA-BBB assay and proved in OF1 mice by ex vivo experiments. Overall, compound 5l seems to be a promising lead compound for the treatment of Alzheimer's diseases.

  5. NADP-Dependent Aldehyde Dehydrogenase from Archaeon Pyrobaculum sp.1860: Structural and Functional Features

    Directory of Open Access Journals (Sweden)

    Ekaterina Yu. Bezsudnova

    2016-01-01

    Full Text Available We present the functional and structural characterization of the first archaeal thermostable NADP-dependent aldehyde dehydrogenase AlDHPyr1147. In vitro, AlDHPyr1147 catalyzes the irreversible oxidation of short aliphatic aldehydes at 60–85°С, and the affinity of AlDHPyr1147 to the NADP+ at 60°С is comparable to that for mesophilic analogues at 25°С. We determined the structures of the apo form of AlDHPyr1147 (3.04 Å resolution, three binary complexes with the coenzyme (1.90, 2.06, and 2.19 Å, and the ternary complex with the coenzyme and isobutyraldehyde as a substrate (2.66 Å. The nicotinamide moiety of the coenzyme is disordered in two binary complexes, while it is ordered in the ternary complex, as well as in the binary complex obtained after additional soaking with the substrate. AlDHPyr1147 structures demonstrate the strengthening of the dimeric contact (as compared with the analogues and the concerted conformational flexibility of catalytic Cys287 and Glu253, as well as Leu254 and the nicotinamide moiety of the coenzyme. A comparison of the active sites of AlDHPyr1147 and dehydrogenases characterized earlier suggests that proton relay systems, which were previously proposed for dehydrogenases of this family, are blocked in AlDHPyr1147, and the proton release in the latter can occur through the substrate channel.

  6. Attentional Selection of Feature Conjunctions Is Accomplished by Parallel and Independent Selection of Single Features.

    Science.gov (United States)

    Andersen, Søren K; Müller, Matthias M; Hillyard, Steven A

    2015-07-08

    Experiments that study feature-based attention have often examined situations in which selection is based on a single feature (e.g., the color red). However, in more complex situations relevant stimuli may not be set apart from other stimuli by a single defining property but by a specific combination of features. Here, we examined sustained attentional selection of stimuli defined by conjunctions of color and orientation. Human observers attended to one out of four concurrently presented superimposed fields of randomly moving horizontal or vertical bars of red or blue color to detect brief intervals of coherent motion. Selective stimulus processing in early visual cortex was assessed by recordings of steady-state visual evoked potentials (SSVEPs) elicited by each of the flickering fields of stimuli. We directly contrasted attentional selection of single features and feature conjunctions and found that SSVEP amplitudes on conditions in which selection was based on a single feature only (color or orientation) exactly predicted the magnitude of attentional enhancement of SSVEPs when attending to a conjunction of both features. Furthermore, enhanced SSVEP amplitudes elicited by attended stimuli were accompanied by equivalent reductions of SSVEP amplitudes elicited by unattended stimuli in all cases. We conclude that attentional selection of a feature-conjunction stimulus is accomplished by the parallel and independent facilitation of its constituent feature dimensions in early visual cortex. The ability to perceive the world is limited by the brain's processing capacity. Attention affords adaptive behavior by selectively prioritizing processing of relevant stimuli based on their features (location, color, orientation, etc.). We found that attentional mechanisms for selection of different features belonging to the same object operate independently and in parallel: concurrent attentional selection of two stimulus features is simply the sum of attending to each of those

  7. Chemical characterization of organic aerosol above a mid-latitude forest reveals a complex mixture of highly-functionalized chemical species and diverse structural features with temporal variability

    Science.gov (United States)

    Gentner, D. R.; Ditto, J.; Barnes, E.; Khare, P.

    2017-12-01

    Highly-functionalized organic compounds are known to be a major component of the complex mixture of the particle-phase compounds that comprise organic aerosol, yet little is known about the identity of many of these compounds, and their formation pathways and roles in atmospheric processes are poorly understood. We present results from the comprehensive chemical speciation of PM10 organic aerosols collected in July 2016 at the remote mid-latitude forest field site during PROPHET. Samples were analyzed via liquid and gas chromatography coupled with a quadrupole time-of-flight tandem mass spectrometry (MS×MS) following electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI). 8 hr samples were collected during day- and night-time sampling periods rather than more typical 24-hour samples. This analysis of the organic aerosol yielded over 12,000 unique compounds for which we have high accuracy molecular masses, formulas, and additional information on structural features using MS×MS. O:C ratios were 0.3 on average, yet the top 10% of compounds ranged 0.7-2.3. 70% and 69% of day- and night-time samples were nitrogen-containing, whereas 26% and 24% contained sulfur, respectively. Within these broader molecular categories, we observed a wide variety of molecular features that reveal a diversity of functional groups and moieties. In this presentation, we present the results of our speciation, temporal variability, connections to air parcel back trajectories and other bulk properties, and potential formation pathways.

  8. Evaluating the Stability of Feature Selectors that Optimize Feature Subset Cardinality

    Czech Academy of Sciences Publication Activity Database

    Somol, Petr; Novovičová, Jana

    2008-01-01

    Roč. 2008, č. 5342 (2008), s. 956-966 ISSN 0302-9743. [Joint IAPR International Workshops SSPR 2008 and SPR 2008. Orlando , 04.12.2008-06.12.2008] R&D Projects: GA AV ČR 1ET400750407; GA MŠk 1M0572; GA ČR GA102/07/1594 Grant - others:GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : Feature selection * stability * relative weighted consistency measure * sequential search * floating search Subject RIV: IN - Informatics, Computer Science http://library.utia.cas.cz/separaty/2008/RO/somol-evaluating the stability of feature selectors that optimize feature subset cardinality.pdf

  9. RESEARCH ON FEATURE POINTS EXTRACTION METHOD FOR BINARY MULTISCALE AND ROTATION INVARIANT LOCAL FEATURE DESCRIPTOR

    Directory of Open Access Journals (Sweden)

    Hongwei Ying

    2014-08-01

    Full Text Available An extreme point of scale space extraction method for binary multiscale and rotation invariant local feature descriptor is studied in this paper in order to obtain a robust and fast method for local image feature descriptor. Classic local feature description algorithms often select neighborhood information of feature points which are extremes of image scale space, obtained by constructing the image pyramid using certain signal transform method. But build the image pyramid always consumes a large amount of computing and storage resources, is not conducive to the actual applications development. This paper presents a dual multiscale FAST algorithm, it does not need to build the image pyramid, but can extract feature points of scale extreme quickly. Feature points extracted by proposed method have the characteristic of multiscale and rotation Invariant and are fit to construct the local feature descriptor.

  10. Guilt by Association: The 13 micron Dust Feature in Circumstellar Shells and Related Spectral Features

    Science.gov (United States)

    Sloan, G. C.; Kraemer, K. E.; Goebel, J. H.; Price, S. D.

    A study of spectra from the SWS on ISO of optically thin oxygen-rich dust shells shows that the strength of the 13 micron dust emission feature is correlated with the CO2 bands (13--17 microns) and dust emission features at 19.8 and 28.1 microns. SRb variables tend to show stronger 13 micron features than Mira variables, suggesting that the presence of the 13 micron and related features depends on pulsation mode and mass-loss rate. The absence of any correlation to dust emission features at 16.8 and 32 microns makes spinel an unlikely carrier. The most plausible carrier of the 13 micron feature remains crystalline alumina, and we suggest that the related dust features may be crystalline silicates. When dust forms in regions of low density, it may condense into crystalline grain structures.

  11. Feature displacement interpolation

    DEFF Research Database (Denmark)

    Nielsen, Mads; Andresen, Per Rønsholt

    1998-01-01

    Given a sparse set of feature matches, we want to compute an interpolated dense displacement map. The application may be stereo disparity computation, flow computation, or non-rigid medical registration. Also estimation of missing image data, may be phrased in this framework. Since the features...... often are very sparse, the interpolation model becomes crucial. We show that a maximum likelihood estimation based on the covariance properties (Kriging) show properties more expedient than methods such as Gaussian interpolation or Tikhonov regularizations, also including scale......-selection. The computational complexities are identical. We apply the maximum likelihood interpolation to growth analysis of the mandibular bone. Here, the features used are the crest-lines of the object surface....

  12. Mid-Infrared Emission Features in the ISM: Feature-to-Features Flux Ratios

    Science.gov (United States)

    Lu, N. Y.

    1998-01-01

    Using a limited, but representative sample of sources in the ISM of our Galaxy with published spectra from the Infrared Space Observatory, we analyze flux ratios between the major mid-IR emission features (EFs) centered around 6.2, 7.7, 8.6 and 11.3 mu, respectively.

  13. FEATUREOUS: AN INTEGRATED ENVIRONMENT FOR FEATURE-CENTRIC ANALYSIS AND MODIFICATION OF OBJECT-ORIENTED SOFTWARE

    DEFF Research Database (Denmark)

    Olszak, Andrzej; Jørgensen, Bo Nørregaard

    2011-01-01

    The decentralized nature of collaborations between objects in object-oriented software makes it difficult to understand the implementations of user-observable program features and their respective interdependencies. As feature-centric program understanding and modification are essential during...... software maintenance and evolution, this situation needs to change. In this paper, we present Featureous, an integrated development environment built on top of the NetBeans IDE that facilitates feature-centric analysis of object-oriented software. Our integrated development environment encompasses...... a lightweight feature location mechanism, a number of reusable analytical views, and necessary APIs for supporting future extensions. The base of the integrated development environment is a conceptual framework comprising of three complementary dimensions of comprehension: perspective, abstraction...

  14. Dapson in heterocyclic chemistry, part VIII: synthesis, molecular docking and anticancer activity of some novel sulfonylbiscompounds carrying biologically active 1,3-dihydropyridine, chromene and chromenopyridine moieties

    Directory of Open Access Journals (Sweden)

    Al-Said Mansour S

    2012-07-01

    Full Text Available Abstract Several new sulfonebiscompounds having a biologically active 1,2-dihydropyridine-2-one 3–19, acrylamide 20, chromene 21, 22 and chromenopyridine 23, 24 moieties were synthesized and evaluated as potential anticancer agents. The structures of the products were confirmed via elemental analyses and spectral data. The screening tests showed that many of the biscompounds obtained exhibited good anticancer activity against human breast cell line (MCF7 comparable to doxorubicin which was used as reference drug. Compounds 11, 17 and 24 showed IC50 values 35.40 μM, 29.86 μM and 30.99 μM, respectively. In order to elucidate the mechanism of action of the synthesized compounds as anticancer agents, docking on the active site of farnesyltransferase and arginine methyltransferase was also performed and good results were obtained.

  15. Improving Naive Bayes with Online Feature Selection for Quick Adaptation to Evolving Feature Usefulness

    Energy Technology Data Exchange (ETDEWEB)

    Pon, R K; Cardenas, A F; Buttler, D J

    2007-09-19

    The definition of what makes an article interesting varies from user to user and continually evolves even for a single user. As a result, for news recommendation systems, useless document features can not be determined a priori and all features are usually considered for interestingness classification. Consequently, the presence of currently useless features degrades classification performance [1], particularly over the initial set of news articles being classified. The initial set of document is critical for a user when considering which particular news recommendation system to adopt. To address these problems, we introduce an improved version of the naive Bayes classifier with online feature selection. We use correlation to determine the utility of each feature and take advantage of the conditional independence assumption used by naive Bayes for online feature selection and classification. The augmented naive Bayes classifier performs 28% better than the traditional naive Bayes classifier in recommending news articles from the Yahoo! RSS feeds.

  16. Ring opening of a resin-bound chiral aziridine with phenol nucleophiles

    DEFF Research Database (Denmark)

    Ottesen, Lars Korsgaard; Jaroszewski, Jerzy W; Franzyk, Henrik

    2010-01-01

    An efficient and versatile solid-phase route for the preparation of aryl-alkyl ethers is described. Regioselective ring opening of a resin-bound chiral aziridine with phenolic nucleophiles constitutes the key feature of the present protocol that allows incorporation of fluorescent moieties...

  17. On Surface-Initiated Atom Transfer Radical Polymerization Using Diazonium Chemistry To Introduce the Initiator Layer

    DEFF Research Database (Denmark)

    Iruthayaraj, Joseph; Chernyy, Sergey; Lillethorup, Mie

    2011-01-01

    This work features the controllability of surface-initiated atom transfer radical polymerization (SI-ATRP) of methyl methacrylate, initiated by a multilayered 2-bromoisobutyryl moiety formed via diazonium chemistry. The thickness as a function of polymerization time has been studied by varying di...

  18. Determination of dopaminergic prodrugs by high-performance liquid chromatography followed by post-column ion-pair extraction

    NARCIS (Netherlands)

    Haas, M; Moolenaar, Frits; Kluppel, A.C A; Dijkstra, D.; Meijer, D.K F; de Zeeuw, D

    1997-01-01

    One possibility to optimize the therapeutic application of dopaminergic compounds with a catechol function is the reversible protection of this moiety using a prodrug approach. Important features in this respect are a proper chemical stability in the gastrointestinal tract, an adequate release rate

  19. Feature confirmation in object perception: Feature integration theory 26 years on from the Treisman Bartlett lecture.

    Science.gov (United States)

    Humphreys, Glyn W

    2016-10-01

    The Treisman Bartlett lecture, reported in the Quarterly Journal of Experimental Psychology in 1988, provided a major overview of the feature integration theory of attention. This has continued to be a dominant account of human visual attention to this day. The current paper provides a summary of the work reported in the lecture and an update on critical aspects of the theory as applied to visual object perception. The paper highlights the emergence of findings that pose significant challenges to the theory and which suggest that revisions are required that allow for (a) several rather than a single form of feature integration, (b) some forms of feature integration to operate preattentively, (c) stored knowledge about single objects and interactions between objects to modulate perceptual integration, (d) the application of feature-based inhibition to object files where visual features are specified, which generates feature-based spreading suppression and scene segmentation, and (e) a role for attention in feature confirmation rather than feature integration in visual selection. A feature confirmation account of attention in object perception is outlined.

  20. Complex Topographic Feature Ontology Patterns

    Science.gov (United States)

    Varanka, Dalia E.; Jerris, Thomas J.

    2015-01-01

    Semantic ontologies are examined as effective data models for the representation of complex topographic feature types. Complex feature types are viewed as integrated relations between basic features for a basic purpose. In the context of topographic science, such component assemblages are supported by resource systems and found on the local landscape. Ontologies are organized within six thematic modules of a domain ontology called Topography that includes within its sphere basic feature types, resource systems, and landscape types. Context is constructed not only as a spatial and temporal setting, but a setting also based on environmental processes. Types of spatial relations that exist between components include location, generative processes, and description. An example is offered in a complex feature type ‘mine.’ The identification and extraction of complex feature types are an area for future research.

  1. Improving mass candidate detection in mammograms via feature maxima propagation and local feature selection.

    Science.gov (United States)

    Melendez, Jaime; Sánchez, Clara I; van Ginneken, Bram; Karssemeijer, Nico

    2014-08-01

    Mass candidate detection is a crucial component of multistep computer-aided detection (CAD) systems. It is usually performed by combining several local features by means of a classifier. When these features are processed on a per-image-location basis (e.g., for each pixel), mismatching problems may arise while constructing feature vectors for classification, which is especially true when the behavior expected from the evaluated features is a peaked response due to the presence of a mass. In this study, two of these problems, consisting of maxima misalignment and differences of maxima spread, are identified and two solutions are proposed. The first proposed method, feature maxima propagation, reproduces feature maxima through their neighboring locations. The second method, local feature selection, combines different subsets of features for different feature vectors associated with image locations. Both methods are applied independently and together. The proposed methods are included in a mammogram-based CAD system intended for mass detection in screening. Experiments are carried out with a database of 382 digital cases. Sensitivity is assessed at two sets of operating points. The first one is the interval of 3.5-15 false positives per image (FPs/image), which is typical for mass candidate detection. The second one is 1 FP/image, which allows to estimate the quality of the mass candidate detector's output for use in subsequent steps of the CAD system. The best results are obtained when the proposed methods are applied together. In that case, the mean sensitivity in the interval of 3.5-15 FPs/image significantly increases from 0.926 to 0.958 (p < 0.0002). At the lower rate of 1 FP/image, the mean sensitivity improves from 0.628 to 0.734 (p < 0.0002). Given the improved detection performance, the authors believe that the strategies proposed in this paper can render mass candidate detection approaches based on image location classification more robust to feature

  2. Opinion mining feature-level using Naive Bayes and feature extraction based analysis dependencies

    Science.gov (United States)

    Sanda, Regi; Baizal, Z. K. Abdurahman; Nhita, Fhira

    2015-12-01

    Development of internet and technology, has major impact and providing new business called e-commerce. Many e-commerce sites that provide convenience in transaction, and consumers can also provide reviews or opinions on products that purchased. These opinions can be used by consumers and producers. Consumers to know the advantages and disadvantages of particular feature of the product. Procuders can analyse own strengths and weaknesses as well as it's competitors products. Many opinions need a method that the reader can know the point of whole opinion. The idea emerged from review summarization that summarizes the overall opinion based on sentiment and features contain. In this study, the domain that become the main focus is about the digital camera. This research consisted of four steps 1) giving the knowledge to the system to recognize the semantic orientation of an opinion 2) indentify the features of product 3) indentify whether the opinion gives a positive or negative 4) summarizing the result. In this research discussed the methods such as Naï;ve Bayes for sentiment classification, and feature extraction algorithm based on Dependencies Analysis, which is one of the tools in Natural Language Processing (NLP) and knowledge based dictionary which is useful for handling implicit features. The end result of research is a summary that contains a bunch of reviews from consumers on the features and sentiment. With proposed method, accuration for sentiment classification giving 81.2 % for positive test data, 80.2 % for negative test data, and accuration for feature extraction reach 90.3 %.

  3. Feature Selection by Reordering

    Czech Academy of Sciences Publication Activity Database

    Jiřina, Marcel; Jiřina jr., M.

    2005-01-01

    Roč. 2, č. 1 (2005), s. 155-161 ISSN 1738-6438 Institutional research plan: CEZ:AV0Z10300504 Keywords : feature selection * data reduction * ordering of features Subject RIV: BA - General Mathematics

  4. DYNAMIC FEATURE SELECTION FOR WEB USER IDENTIFICATION ON LINGUISTIC AND STYLISTIC FEATURES OF ONLINE TEXTS

    Directory of Open Access Journals (Sweden)

    A. A. Vorobeva

    2017-01-01

    Full Text Available The paper deals with identification and authentication of web users participating in the Internet information processes (based on features of online texts.In digital forensics web user identification based on various linguistic features can be used to discover identity of individuals, criminals or terrorists using the Internet to commit cybercrimes. Internet could be used as a tool in different types of cybercrimes (fraud and identity theft, harassment and anonymous threats, terrorist or extremist statements, distribution of illegal content and information warfare. Linguistic identification of web users is a kind of biometric identification, it can be used to narrow down the suspects, identify a criminal and prosecute him. Feature set includes various linguistic and stylistic features extracted from online texts. We propose dynamic feature selection for each web user identification task. Selection is based on calculating Manhattan distance to k-nearest neighbors (Relief-f algorithm. This approach improves the identification accuracy and minimizes the number of features. Experiments were carried out on several datasets with different level of class imbalance. Experiment results showed that features relevance varies in different set of web users (probable authors of some text; features selection for each set of web users improves identification accuracy by 4% at the average that is approximately 1% higher than with the use of static set of features. The proposed approach is most effective for a small number of training samples (messages per user.

  5. Temporal Feature Integration for Music Organisation

    DEFF Research Database (Denmark)

    Meng, Anders

    2006-01-01

    This Ph.D. thesis focuses on temporal feature integration for music organisation. Temporal feature integration is the process of combining all the feature vectors of a given time-frame into a single new feature vector in order to capture relevant information in the frame. Several existing methods...... for handling sequences of features are formulated in the temporal feature integration framework. Two datasets for music genre classification have been considered as valid test-beds for music organisation. Human evaluations of these, have been obtained to access the subjectivity on the datasets. Temporal...... ranking' approach is proposed for ranking the short-time features at larger time-scales according to their discriminative power in a music genre classification task. The multivariate AR (MAR) model has been proposed for temporal feature integration. It effectively models local dynamical structure...

  6. Feature Inference Learning and Eyetracking

    Science.gov (United States)

    Rehder, Bob; Colner, Robert M.; Hoffman, Aaron B.

    2009-01-01

    Besides traditional supervised classification learning, people can learn categories by inferring the missing features of category members. It has been proposed that feature inference learning promotes learning a category's internal structure (e.g., its typical features and interfeature correlations) whereas classification promotes the learning of…

  7. Structural requirements of the human sodium-dependent bile acid transporter (hASBT): Role of 3- and 7-OH moieties on binding and translocation of bile acids

    Science.gov (United States)

    González, Pablo M.; Lagos, Carlos F.; Ward, Weslyn C.; Polli, James E.

    2014-01-01

    Bile acids (BAs) are the end products of cholesterol metabolism. One of the critical steps in their biosynthesis involves the isomerization of the 3β-hydroxyl (-OH) group on the cholestane ring to the common 3α-configuration on BAs. BAs are actively recaptured from the small intestine by the human Apical Sodium-dependent Bile Acid Transporter (hASBT) with high affinity and capacity. Previous studies have suggested that no particular hydroxyl group on BAs is critical for binding or transport by hASBT, even though 3β-hydroxylated BAs were not examined. The aim of this study was to elucidate the role of the 3α-OH group on BAs binding and translocation by hASBT. Ten 3β-hydroxylated BAs (Iso-bile acids, iBAs) were synthesized, characterized, and subjected to hASBT inhibition and uptake studies. hASBT inhibition and uptake kinetics of iBAs were compared to that of native 3α-OH BAs. Glycine conjugates of native and isomeric BAs were subjected to molecular dynamics simulations in order to identify topological descriptors related to binding and translocation by hASBT. Iso-BAs bound to hASBT with lower affinity and exhibited reduced translocation than their respective 3α-epimers. Kinetic data suggests that, in contrast to native BAs where hASBT binding is the rate-limiting step, iBAs transport was rate-limited by translocation and not binding. Remarkably, 7-dehydroxylated iBAs were not hASBT substrates, highlighting the critical role of 7-OH group on BA translocation by hASBT, especially for iBAs. Conformational analysis of gly-iBAs and native BAs identified topological features for optimal binding as: concave steroidal nucleus, 3-OH “on-” or below-steroidal plane, 7-OH below-plane, and 12-OH moiety towards-plane. Our results emphasize the relevance of the 3α-OH group on BAs for proper hASBT binding and transport and revealed the critical role of 7-OH group on BA translocation, particularly in the absence of a 3α-OH group. Results have implications for BA

  8. Hypothesis testing for differentially correlated features.

    Science.gov (United States)

    Sheng, Elisa; Witten, Daniela; Zhou, Xiao-Hua

    2016-10-01

    In a multivariate setting, we consider the task of identifying features whose correlations with the other features differ across conditions. Such correlation shifts may occur independently of mean shifts, or differences in the means of the individual features across conditions. Previous approaches for detecting correlation shifts consider features simultaneously, by computing a correlation-based test statistic for each feature. However, since correlations involve two features, such approaches do not lend themselves to identifying which feature is the culprit. In this article, we instead consider a serial testing approach, by comparing columns of the sample correlation matrix across two conditions, and removing one feature at a time. Our method provides a novel perspective and favorable empirical results compared with competing approaches. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Synthesis, characterization, X-ray crystal structure and DFT calculations of 4-([2,2':6',2''-terpyridin]- 4'-ylphenol

    Directory of Open Access Journals (Sweden)

    Cesar Sierra

    2018-01-01

    intraligand charge transfer character (ICT, while the high-energy band is a common feature of π-π* transitions of the Tpy moiety. The S1→S0 emission transition also has an ICT character, with a 90% contribution from the HOMO→LUMO transitions.

  10. Emergent interfaces for feature modularization

    CERN Document Server

    Ribeiro, Márcio; Brabrand, Claus

    2014-01-01

    Developers frequently introduce errors into software systems when they fail to recognise module dependencies. Using forty-three software families and Software Product Lines (SPLs), where the majority are commonly used in industrial practice, the authors reports on the feature modularization problem and provides a study of how often it may occur in practice. To solve the problem they present the concept of emergent feature modularization which aims to establish contracts between features to prevent developers from breaking other features when performing a maintenance task.

  11. A comparison of an ATPase from the archaebacterium Halobacterium saccharovorum with the F1 moiety from the Escherichia coli ATP Synthase

    Science.gov (United States)

    Stan-Lotter, Helga; Hochstein, Lawrence I.

    1989-01-01

    A purified ATPase associated with membranes from Halobacterium saccharovorum was compared with the F sub 1 moiety from the Escherichia coli ATP Synthase. The halobacterial enzyme was composed of two major (I and II) and two minor subunits (III and IV), whose molecular masses were 87 kDa, 60 kDa, 29 kDa, and 20 kDa, respectively. The isoelectric points of these subunits ranged from 4.1 to 4.8, which in the case of the subunits I and II was consistent with the presence of an excess of acidic amino acids (20 to 22 Mol percent). Peptide mapping of sodium dodecylsulfate-denatured subunits I and II showed no relationship between the primary structures of the individual halobacterial subunits or similarities to the subunits of the F sub 1 ATPase (EC 3.6.1.34) from E. coli. Trypsin inactivation of the halobacterial ATPase was accompanied by the partial degradation of the major subunits. This observation, taken in conjunction with molecular masses of the subunits and the native enzyme, was consistent with the previously proposed stoichiometry of 2:2:1:1. These results suggest that H. saccharovorum, and possibly, Halobacteria in general, possess an ATPase which is unlike the ubiquitous F sub o F sub 1 - ATP Synthase.

  12. Writer identification using curvature-free features

    NARCIS (Netherlands)

    He, Sheng; Schomaker, Lambertus

    2017-01-01

    Feature engineering takes a very important role in writer identification which has been widely studied in the literature. Previous works have shown that the joint feature distribution of two properties can improve the performance. The joint feature distribution makes feature relationships explicit

  13. Mycoplasma infection of cell lines can simulate the expression of Fc receptors by binding of the carbohydrate moiety of antibodies.

    Science.gov (United States)

    Lemke, H; Krausse, R; Lorenzen, J; Havsteen, B

    1985-05-01

    During the production of Fc receptor (FcR)-bearing hybridomas it was observed with a particular monoclonal anti-sheep red blood cell antibody (anti-SRBC 1/5, IgG1) that the contamination with Mycoplasma arginini of in vitro cultured cell lines leads to an apparent FcR activity. This property did not correspond with the serological typing since other antibodies of the same isotype could not support FcR rosette formation. Another mycoplasma strain M. orale lacked this property. Analysis of the binding reaction revealed that M. arginini contains a lectin which binds the carbohydrate moiety of the anti-SRBC 1/5 antibody, i.e. anti-SRBC 1/5 synthesized under the influence of tunicamycin or deglycosylated by NaIO4 oxidation did not support rosette formation. These data suggest that binding of antibodies to certain mycoplasma strains may be a pathogenic factor during mycoplasma infections by masking the microorganisms with the host's own defense molecules. The experiments with M. arginini-infected cell lines gain immunological importance since we obtained identical results with staphylococcal protein A, as another bacteriological FcR, and cell lines expressing intrinsic membrane FcR. Although it is an open question whether the glycoconjugates are directly bound by the FcR or else by influencing the three-dimensional structure of the antibodies, it seems possible that FcR in general may be lectins.

  14. Patterns of Dysmorphic Features in Schizophrenia

    Science.gov (United States)

    Scutt, L.E.; Chow, E.W.C.; Weksberg, R.; Honer, W.G.; Bassett, Anne S.

    2011-01-01

    Congenital dysmorphic features are prevalent in schizophrenia and may reflect underlying neurodevelopmental abnormalities. A cluster analysis approach delineating patterns of dysmorphic features has been used in genetics to classify individuals into more etiologically homogeneous subgroups. In the present study, this approach was applied to schizophrenia, using a sample with a suspected genetic syndrome as a testable model. Subjects (n = 159) with schizophrenia or schizoaffective disorder were ascertained from chronic patient populations (random, n=123) or referred with possible 22q11 deletion syndrome (referred, n = 36). All subjects were evaluated for presence or absence of 70 reliably assessed dysmorphic features, which were used in a three-step cluster analysis. The analysis produced four major clusters with different patterns of dysmorphic features. Significant between-cluster differences were found for rates of 37 dysmorphic features (P dysmorphic features (P = 0.0001), and validating features not used in the cluster analysis: mild mental retardation (P = 0.001) and congenital heart defects (P = 0.002). Two clusters (1 and 4) appeared to represent more developmental subgroups of schizophrenia with elevated rates of dysmorphic features and validating features. Cluster 1 (n = 27) comprised mostly referred subjects. Cluster 4 (n= 18) had a different pattern of dysmorphic features; one subject had a mosaic Turner syndrome variant. Two other clusters had lower rates and patterns of features consistent with those found in previous studies of schizophrenia. Delineating patterns of dysmorphic features may help identify subgroups that could represent neurodevelopmental forms of schizophrenia with more homogeneous origins. PMID:11803519

  15. Object feature extraction and recognition model

    International Nuclear Information System (INIS)

    Wan Min; Xiang Rujian; Wan Yongxing

    2001-01-01

    The characteristics of objects, especially flying objects, are analyzed, which include characteristics of spectrum, image and motion. Feature extraction is also achieved. To improve the speed of object recognition, a feature database is used to simplify the data in the source database. The feature vs. object relationship maps are stored in the feature database. An object recognition model based on the feature database is presented, and the way to achieve object recognition is also explained

  16. Solar Features

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar feature datasets contributed by a number of national and private solar observatories located worldwide.

  17. Search features of digital libraries

    Directory of Open Access Journals (Sweden)

    Alastair G. Smith

    2000-01-01

    Full Text Available Traditional on-line search services such as Dialog, DataStar and Lexis provide a wide range of search features (boolean and proximity operators, truncation, etc. This paper discusses the use of these features for effective searching, and argues that these features are required, regardless of advances in search engine technology. The literature on on-line searching is reviewed, identifying features that searchers find desirable for effective searching. A selective survey of current digital libraries available on the Web was undertaken, identifying which search features are present. The survey indicates that current digital libraries do not implement a wide range of search features. For instance: under half of the examples included controlled vocabulary, under half had proximity searching, only one enabled browsing of term indexes, and none of the digital libraries enable searchers to refine an initial search. Suggestions are made for enhancing the search effectiveness of digital libraries, for instance by: providing a full range of search operators, enabling browsing of search terms, enhancement of records with controlled vocabulary, enabling the refining of initial searches, etc.

  18. [Feature extraction for breast cancer data based on geometric algebra theory and feature selection using differential evolution].

    Science.gov (United States)

    Li, Jing; Hong, Wenxue

    2014-12-01

    The feature extraction and feature selection are the important issues in pattern recognition. Based on the geometric algebra representation of vector, a new feature extraction method using blade coefficient of geometric algebra was proposed in this study. At the same time, an improved differential evolution (DE) feature selection method was proposed to solve the elevated high dimension issue. The simple linear discriminant analysis was used as the classifier. The result of the 10-fold cross-validation (10 CV) classification of public breast cancer biomedical dataset was more than 96% and proved superior to that of the original features and traditional feature extraction method.

  19. Tumor recognition in wireless capsule endoscopy images using textural features and SVM-based feature selection.

    Science.gov (United States)

    Li, Baopu; Meng, Max Q-H

    2012-05-01

    Tumor in digestive tract is a common disease and wireless capsule endoscopy (WCE) is a relatively new technology to examine diseases for digestive tract especially for small intestine. This paper addresses the problem of automatic recognition of tumor for WCE images. Candidate color texture feature that integrates uniform local binary pattern and wavelet is proposed to characterize WCE images. The proposed features are invariant to illumination change and describe multiresolution characteristics of WCE images. Two feature selection approaches based on support vector machine, sequential forward floating selection and recursive feature elimination, are further employed to refine the proposed features for improving the detection accuracy. Extensive experiments validate that the proposed computer-aided diagnosis system achieves a promising tumor recognition accuracy of 92.4% in WCE images on our collected data.

  20. Volcanic features of Io

    International Nuclear Information System (INIS)

    Carr, M.H.; Masursky, H.; Strom, R.G.; Terrile, R.J.

    1979-01-01

    The volcanic features of Io as detected during the Voyager mission are discussed. The volcanic activity is apparently higher than on any other body in the Solar System. Its volcanic landforms are compared with features on Earth to indicate the type of volcanism present on Io. (U.K.)

  1. Evaluating Stability and Comparing Output of Feature Selectors that Optimize Feature Subset Cardinality

    Czech Academy of Sciences Publication Activity Database

    Somol, Petr; Novovičová, Jana

    2010-01-01

    Roč. 32, č. 11 (2010), s. 1921-1939 ISSN 0162-8828 R&D Projects: GA MŠk 1M0572; GA ČR GA102/08/0593; GA ČR GA102/07/1594 Grant - others:GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : feature selection * feature stability * stability measures * similarity measures * sequential search * individual ranking * feature subset-size optimization * high dimensionality * small sample size Subject RIV: BD - Theory of Information Impact factor: 5.027, year: 2010 http://library.utia.cas.cz/separaty/2010/RO/somol-0348726.pdf

  2. Site Features

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset consists of various site features from multiple Superfund sites in U.S. EPA Region 8. These data were acquired from multiple sources at different times...

  3. New features in MEDM

    International Nuclear Information System (INIS)

    Evans, K. Jr.

    1999-01-01

    MEDM, which is derived from Motif Editor and Display Manager, is the primary graphical interface to the EPICS control system. This paper describes new features that have been added to MEDM in the last two years. These features include new editing capabilities, a PV Info dialog box, a means of specifying limits and precision, a new implementation of the Cartesian Plot, new features for several objects, new capability for the Related Display, help, a user-configurable Execute Menu, reconfigured start-up options, and availability for Windows 95/98/NT. Over one hundred bugs have been fixed, and the program is quite stable and in extensive use

  4. Tolerance-Based Feature Transforms

    NARCIS (Netherlands)

    Reniers, Dennie; Telea, Alexandru

    2007-01-01

    Tolerance-based feature transforms (TFTs) assign to each pixel in an image not only the nearest feature pixels on the boundary (origins), but all origins from the minimum distance up to a user-defined tolerance. In this paper, we compare four simple-to-implement methods for computing TFTs on binary

  5. Invariant Feature Matching for Image Registration Application Based on New Dissimilarity of Spatial Features

    Science.gov (United States)

    Mousavi Kahaki, Seyed Mostafa; Nordin, Md Jan; Ashtari, Amir H.; J. Zahra, Sophia

    2016-01-01

    An invariant feature matching method is proposed as a spatially invariant feature matching approach. Deformation effects, such as affine and homography, change the local information within the image and can result in ambiguous local information pertaining to image points. New method based on dissimilarity values, which measures the dissimilarity of the features through the path based on Eigenvector properties, is proposed. Evidence shows that existing matching techniques using similarity metrics—such as normalized cross-correlation, squared sum of intensity differences and correlation coefficient—are insufficient for achieving adequate results under different image deformations. Thus, new descriptor’s similarity metrics based on normalized Eigenvector correlation and signal directional differences, which are robust under local variation of the image information, are proposed to establish an efficient feature matching technique. The method proposed in this study measures the dissimilarity in the signal frequency along the path between two features. Moreover, these dissimilarity values are accumulated in a 2D dissimilarity space, allowing accurate corresponding features to be extracted based on the cumulative space using a voting strategy. This method can be used in image registration applications, as it overcomes the limitations of the existing approaches. The output results demonstrate that the proposed technique outperforms the other methods when evaluated using a standard dataset, in terms of precision-recall and corner correspondence. PMID:26985996

  6. Invariant Feature Matching for Image Registration Application Based on New Dissimilarity of Spatial Features.

    Directory of Open Access Journals (Sweden)

    Seyed Mostafa Mousavi Kahaki

    Full Text Available An invariant feature matching method is proposed as a spatially invariant feature matching approach. Deformation effects, such as affine and homography, change the local information within the image and can result in ambiguous local information pertaining to image points. New method based on dissimilarity values, which measures the dissimilarity of the features through the path based on Eigenvector properties, is proposed. Evidence shows that existing matching techniques using similarity metrics--such as normalized cross-correlation, squared sum of intensity differences and correlation coefficient--are insufficient for achieving adequate results under different image deformations. Thus, new descriptor's similarity metrics based on normalized Eigenvector correlation and signal directional differences, which are robust under local variation of the image information, are proposed to establish an efficient feature matching technique. The method proposed in this study measures the dissimilarity in the signal frequency along the path between two features. Moreover, these dissimilarity values are accumulated in a 2D dissimilarity space, allowing accurate corresponding features to be extracted based on the cumulative space using a voting strategy. This method can be used in image registration applications, as it overcomes the limitations of the existing approaches. The output results demonstrate that the proposed technique outperforms the other methods when evaluated using a standard dataset, in terms of precision-recall and corner correspondence.

  7. LEGO-Inspired Drug Design: Unveiling a Class of Benzo[d]thiazoles Containing a 3,4-Dihydroxyphenyl Moiety as Plasma Membrane H+ -ATPase Inhibitors.

    Science.gov (United States)

    Tung, Truong-Thanh; Dao, Trong T; Junyent, Marta G; Palmgren, Michael; Günther-Pomorski, Thomas; Fuglsang, Anja T; Christensen, Søren B; Nielsen, John

    2018-01-08

    The fungal plasma membrane H + -ATPase (Pma1p) is a potential target for the discovery of new antifungal agents. Surprisingly, no structure-activity relationship studies for small molecules targeting Pma1p have been reported. Herein, we disclose a LEGO-inspired fragment assembly strategy for the design, synthesis, and discovery of benzo[d]thiazoles containing a 3,4-dihydroxyphenyl moiety as potential Pma1p inhibitors. A series of 2-(benzo[d]thiazol-2-ylthio)-1-(3,4-dihydroxyphenyl)ethanones was found to inhibit Pma1p, with the most potent IC 50 value of 8 μm in an in vitro plasma membrane H + -ATPase assay. These compounds were also found to strongly inhibit the action of proton pumping when Pma1p was reconstituted into liposomes. 1-(3,4-Dihydroxyphenyl)-2-((6-(trifluoromethyl)benzo[d]thiazol-2-yl)thio)ethan-1-one (compound 38) showed inhibitory activities on the growth of Candida albicans and Saccharomyces cerevisiae, which could be correlated and substantiated with the ability to inhibit Pma1p in vitro. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Unique N-Glycan Moieties of the 66-kDa Cell Wall Glycoprotein from the Red Microalga Porphyridium sp.

    Science.gov (United States)

    Levy-Ontman, Oshrat; Arad, Shoshana (Malis); Harvey, David J.; Parsons, Thomas B.; Fairbanks, Antony; Tekoah, Yoram

    2011-01-01

    We report here the structural determination of the N-linked glycans in the 66-kDa glycoprotein, part of the unique sulfated complex cell wall polysaccharide of the red microalga Porphyridium sp. Structures were elucidated by a combination of normal phase/reverse phase HPLC, positive ion MALDI-TOF MS, negative ion electrospray ionization, and MS/MS. The sugar moieties of the glycoprotein consisted of at least four fractions of N-linked glycans, each composed of the same four monosaccharides, GlcNAc, Man, 6-O-MeMan, and Xyl, with compositions Man8–9Xyl1–2Me3GlcNAc2. The present study is the first report of N-glycans with the terminal Xyl attached to the 6-mannose branch of the 6-antenna and to the 3-oxygen of the penultimate (core) GlcNAc. Another novel finding was that all four glycans contain three O-methylmannose residues in positions that have never been reported before. Although it is known that some lower organisms are able to methylate terminal monosaccharides in glycans, the present study on Porphyridium sp. is the first describing an organism that is able to methylate non-terminal mannose residues. This study will thus contribute to understanding of N-glycosylation in algae and might shed light on the evolutionary development from prokaryotes to multicellular organisms. It also may contribute to our understanding of the red algae polysaccharide formation. The additional importance of this research lies in its potential for biotechnological applications, especially in evaluating the use of microalgae as cell factories for the production of therapeutic proteins. PMID:21515680

  9. Distinct moieties underlie biphasic H+ gating of connexin43 channels, producing a pH optimum for intercellular communication

    Science.gov (United States)

    Garciarena, Carolina D.; Malik, Akif; Swietach, Pawel; Moreno, Alonso P.; Vaughan-Jones, Richard D.

    2018-01-01

    Most mammalian cells can intercommunicate via connexin-assembled, gap-junctional channels. To regulate signal transmission, connexin (Cx) channel permeability must respond dynamically to physiological and pathophysiological stimuli. One key stimulus is intracellular pH (pHi), which is modulated by a tissue’s metabolic and perfusion status. Our understanding of the molecular mechanism of H+ gating of Cx43 channels—the major isoform in the heart and brain—is incomplete. To interrogate the effects of acidic and alkaline pHi on Cx43 channels, we combined voltage-clamp electrophysiology with pHi imaging and photolytic H+ uncaging, performed over a range of pHi values. We demonstrate that Cx43 channels expressed in HeLa or N2a cell pairs are gated biphasically by pHi via a process that consists of activation by H+ ions at alkaline pHi and inhibition at more acidic pHi. For Cx43 channel–mediated solute/ion transmission, the ensemble of these effects produces a pHi optimum, near resting pHi. By using Cx43 mutants, we demonstrate that alkaline gating involves cysteine residues of the C terminus and is independent of motifs previously implicated in acidic gating. Thus, we present a molecular mechanism by which cytoplasmic acid–base chemistry fine tunes intercellular communication and establishes conditions for the optimal transmission of solutes and signals in tissues, such as the heart and brain.—Garciarena, C. D., Malik, A., Swietach, P., Moreno, A. P., Vaughan-Jones, R. D. Distinct moieties underlie biphasic H+ gating of connexin43 channels, producing a pH optimum for intercellular communication. PMID:29183963

  10. Crowding with conjunctions of simple features.

    Science.gov (United States)

    Põder, Endel; Wagemans, Johan

    2007-11-20

    Several recent studies have related crowding with the feature integration stage in visual processing. In order to understand the mechanisms involved in this stage, it is important to use stimuli that have several features to integrate, and these features should be clearly defined and measurable. In this study, Gabor patches were used as target and distractor stimuli. The stimuli differed in three dimensions: spatial frequency, orientation, and color. A group of 3, 5, or 7 objects was presented briefly at 4 deg eccentricity of the visual field. The observers' task was to identify the object located in the center of the group. A strong effect of the number of distractors was observed, consistent with various spatial pooling models. The analysis of incorrect responses revealed that these were a mix of feature errors and mislocalizations of the target object. Feature errors were not purely random, but biased by the features of distractors. We propose a simple feature integration model that predicts most of the observed regularities.

  11. Sensitivity to feature displacement in familiar and unfamiliar faces: beyond the internal/external feature distinction.

    Science.gov (United States)

    Brooks, Kevin R; Kemp, Richard I

    2007-01-01

    Previous studies of face recognition and of face matching have shown a general improvement for the processing of internal features as a face becomes more familiar to the participant. In this study, we used a psychophysical two-alternative forced-choice paradigm to investigate thresholds for the detection of a displacement of the eyes, nose, mouth, or ears for familiar and unfamiliar faces. No clear division between internal and external features was observed. Rather, for familiar (compared to unfamiliar) faces participants were more sensitive to displacements of internal features such as the eyes or the nose; yet, for our third internal feature-the mouth no such difference was observed. Despite large displacements, many subjects were unable to perform above chance when stimuli involved shifts in the position of the ears. These results are consistent with the proposal that familiarity effects may be mediated by the construction of a robust representation of a face, although the involvement of attention in the encoding of face stimuli cannot be ruled out. Furthermore, these effects are mediated by information from a spatial configuration of features, rather than by purely feature-based information.

  12. Feature extraction for magnetic domain images of magneto-optical recording films using gradient feature segmentation

    International Nuclear Information System (INIS)

    Quanqing, Zhu.; Xinsai, Wang; Xuecheng, Zou; Haihua, Li; Xiaofei, Yang

    2002-01-01

    In this paper, we present a method to realize feature extraction on low contrast magnetic domain images of magneto-optical recording films. The method is based on the following three steps: first, Lee-filtering method is adopted to realize pre-filtering and noise reduction; this is followed by gradient feature segmentation, which separates the object area from the background area; finally the common linking method is adopted and the characteristic parameters of magnetic domain are calculated. We describe these steps with particular emphasis on the gradient feature segmentation. The results show that this method has advantages over other traditional ones for feature extraction of low contrast images

  13. Discrete Feature Model (DFM) User Documentation

    Energy Technology Data Exchange (ETDEWEB)

    Geier, Joel (Clearwater Hardrock Consulting, Corvallis, OR (United States))

    2008-06-15

    This manual describes the Discrete-Feature Model (DFM) software package for modelling groundwater flow and solute transport in networks of discrete features. A discrete-feature conceptual model represents fractures and other water-conducting features around a repository as discrete conductors surrounded by a rock matrix which is usually treated as impermeable. This approximation may be valid for crystalline rocks such as granite or basalt, which have very low permeability if macroscopic fractures are excluded. A discrete feature is any entity that can conduct water and permit solute transport through bedrock, and can be reasonably represented as a piecewise-planar conductor. Examples of such entities may include individual natural fractures (joints or faults), fracture zones, and disturbed-zone features around tunnels (e.g. blasting-induced fractures or stress-concentration induced 'onion skin' fractures around underground openings). In a more abstract sense, the effectively discontinuous nature of pathways through fractured crystalline bedrock may be idealized as discrete, equivalent transmissive features that reproduce large-scale observations, even if the details of connective paths (and unconnected domains) are not precisely known. A discrete-feature model explicitly represents the fundamentally discontinuous and irregularly connected nature of systems of such systems, by constraining flow and transport to occur only within such features and their intersections. Pathways for flow and solute transport in this conceptualization are a consequence not just of the boundary conditions and hydrologic properties (as with continuum models), but also the irregularity of connections between conductive/transmissive features. The DFM software package described here is an extensible code for investigating problems of flow and transport in geological (natural or human-altered) systems that can be characterized effectively in terms of discrete features. With this

  14. Discrete Feature Model (DFM) User Documentation

    International Nuclear Information System (INIS)

    Geier, Joel

    2008-06-01

    This manual describes the Discrete-Feature Model (DFM) software package for modelling groundwater flow and solute transport in networks of discrete features. A discrete-feature conceptual model represents fractures and other water-conducting features around a repository as discrete conductors surrounded by a rock matrix which is usually treated as impermeable. This approximation may be valid for crystalline rocks such as granite or basalt, which have very low permeability if macroscopic fractures are excluded. A discrete feature is any entity that can conduct water and permit solute transport through bedrock, and can be reasonably represented as a piecewise-planar conductor. Examples of such entities may include individual natural fractures (joints or faults), fracture zones, and disturbed-zone features around tunnels (e.g. blasting-induced fractures or stress-concentration induced 'onion skin' fractures around underground openings). In a more abstract sense, the effectively discontinuous nature of pathways through fractured crystalline bedrock may be idealized as discrete, equivalent transmissive features that reproduce large-scale observations, even if the details of connective paths (and unconnected domains) are not precisely known. A discrete-feature model explicitly represents the fundamentally discontinuous and irregularly connected nature of systems of such systems, by constraining flow and transport to occur only within such features and their intersections. Pathways for flow and solute transport in this conceptualization are a consequence not just of the boundary conditions and hydrologic properties (as with continuum models), but also the irregularity of connections between conductive/transmissive features. The DFM software package described here is an extensible code for investigating problems of flow and transport in geological (natural or human-altered) systems that can be characterized effectively in terms of discrete features. With this software, the

  15. Commentary

    Indian Academy of Sciences (India)

    Madhu

    2006-07-18

    Jul 18, 2006 ... effective viscosity comparable to that of light oil (Edidin 2003). In addition, membranes exhibit a considerable degree of anisotropy along the ... and amide moieties of the peptide backbone, a feature shared with the selectivity filter of the bacterial. KcsA potassium channel (Chattopadhyay and Kelkar 2005).

  16. Copper(i)-induced amplification of a [2]catenane in a virtual dynamic library of macrocyclic alkenes

    NARCIS (Netherlands)

    Berrocal, J.A.; Nieuwenhuizen, M.M.L.; Mandolini, L.; Meijer, E.W.; Di Stefano, S.

    2014-01-01

    Olefin cross-metathesis of diluted dichloromethane solutions (=0.15 M) of the 28-membered macrocyclic alkene C1, featuring a 1,10-phenanthroline moiety in the backbone, as well as of catenand 1, composed of two identical interlocked C1 units, generates families of noninterlocked oligomers Ci. The

  17. Degree of contribution (DoC) feature selection algorithm for structural brain MRI volumetric features in depression detection.

    Science.gov (United States)

    Kipli, Kuryati; Kouzani, Abbas Z

    2015-07-01

    Accurate detection of depression at an individual level using structural magnetic resonance imaging (sMRI) remains a challenge. Brain volumetric changes at a structural level appear to have importance in depression biomarkers studies. An automated algorithm is developed to select brain sMRI volumetric features for the detection of depression. A feature selection (FS) algorithm called degree of contribution (DoC) is developed for selection of sMRI volumetric features. This algorithm uses an ensemble approach to determine the degree of contribution in detection of major depressive disorder. The DoC is the score of feature importance used for feature ranking. The algorithm involves four stages: feature ranking, subset generation, subset evaluation, and DoC analysis. The performance of DoC is evaluated on the Duke University Multi-site Imaging Research in the Analysis of Depression sMRI dataset. The dataset consists of 115 brain sMRI scans of 88 healthy controls and 27 depressed subjects. Forty-four sMRI volumetric features are used in the evaluation. The DoC score of forty-four features was determined as the accuracy threshold (Acc_Thresh) was varied. The DoC performance was compared with that of four existing FS algorithms. At all defined Acc_Threshs, DoC outperformed the four examined FS algorithms for the average classification score and the maximum classification score. DoC has a good ability to generate reduced-size subsets of important features that could yield high classification accuracy. Based on the DoC score, the most discriminant volumetric features are those from the left-brain region.

  18. Flow-like Features On Europa

    Science.gov (United States)

    1997-01-01

    This image shows features on Jupiter's moon Europa that may be 'flows' from ice volcanoes. It was taken by the Galileo spacecraft solid state imaging (CCD) system during its seventh orbit around Jupiter. North is to the top of the image. The sun illuminates the scene from the left, showing features with shapes similar to lava flows on Earth. Two such features can be seen in the northwest corner of the image. The southern feature appears to have flowed over a ridge along its western edge. Scientists use these types of relationships to determine which feature formed first. In this case, the ridge probably formed before the flow-like feature that covers it.The image, centered at 22.6 degrees north latitude and 106.7 degrees west longitude, covers an area of 180 by 215 kilometers (112 by 134 miles). The smallest distinguishable features in the image are about 1.1 kilometers (0.7 miles) across. This image was obtained on April 28, 1997, when Galileo was 27,590 kilometers (16,830 miles) from Europa.The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  19. Feature Extraction

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Feature selection and reduction are key to robust multivariate analyses. In this talk I will focus on pros and cons of various variable selection methods and focus on those that are most relevant in the context of HEP.

  20. Autonomic healable waterborne organic-inorganic polyurethane hybrids based on aromatic disulfide moieties

    Directory of Open Access Journals (Sweden)

    R. H. Aguirresarobe

    2017-04-01

    Full Text Available Aromatic disulfide dynamic structures were incorporated as chain extenders in waterborne organic-inorganic polyurethane hybrids in order to provide autonomic healable characteristics. The synthesis was carried out following the acetone process methodology and the influence of the introduction of the healing agents in the polymer dispersion stability was analyzed. After the crosslinking process at room temperature, organic-inorganic hybrid films, which presented autonomic healing characteristics, were obtained. These features were evaluated by means of stress-strain tests and the films showed repetitive healing abilities. Thus, the optimum healing time at room temperature (25 °C as well as the influence of different parameters in the healing efficiency, such the aromatic disulfide concentration or the physical properties of the polymer matrix were analyzed.

  1. Video genre classification using multimodal features

    Science.gov (United States)

    Jin, Sung Ho; Bae, Tae Meon; Choo, Jin Ho; Ro, Yong Man

    2003-12-01

    We propose a video genre classification method using multimodal features. The proposed method is applied for the preprocessing of automatic video summarization or the retrieval and classification of broadcasting video contents. Through a statistical analysis of low-level and middle-level audio-visual features in video, the proposed method can achieve good performance in classifying several broadcasting genres such as cartoon, drama, music video, news, and sports. In this paper, we adopt MPEG-7 audio-visual descriptors as multimodal features of video contents and evaluate the performance of the classification by feeding the features into a decision tree-based classifier which is trained by CART. The experimental results show that the proposed method can recognize several broadcasting video genres with a high accuracy and the classification performance with multimodal features is superior to the one with unimodal features in the genre classification.

  2. Particle swarm optimization based feature enhancement and feature selection for improved emotion recognition in speech and glottal signals.

    Science.gov (United States)

    Muthusamy, Hariharan; Polat, Kemal; Yaacob, Sazali

    2015-01-01

    In the recent years, many research works have been published using speech related features for speech emotion recognition, however, recent studies show that there is a strong correlation between emotional states and glottal features. In this work, Mel-frequency cepstralcoefficients (MFCCs), linear predictive cepstral coefficients (LPCCs), perceptual linear predictive (PLP) features, gammatone filter outputs, timbral texture features, stationary wavelet transform based timbral texture features and relative wavelet packet energy and entropy features were extracted from the emotional speech (ES) signals and its glottal waveforms(GW). Particle swarm optimization based clustering (PSOC) and wrapper based particle swarm optimization (WPSO) were proposed to enhance the discerning ability of the features and to select the discriminating features respectively. Three different emotional speech databases were utilized to gauge the proposed method. Extreme learning machine (ELM) was employed to classify the different types of emotions. Different experiments were conducted and the results show that the proposed method significantly improves the speech emotion recognition performance compared to previous works published in the literature.

  3. MRI features associated with acute appendicitis

    NARCIS (Netherlands)

    Leeuwenburgh, Marjolein M. N.; Jensch, Sebastiaan; Gratama, Jan W. C.; Spilt, Aart; Wiarda, Bart M.; van Es, H. Wouter; Cobben, Lodewijk P. J.; Bossuyt, Patrick M. M.; Boermeester, Marja A.; Stoker, Jaap; Bouma, Wim H.; Houdijk, Alexander P. J.; Richir, Milan C.; Stockmann, Hein B. A. C.; Wiezer, Marinus J.; Verhagen, Thijs

    2014-01-01

    To identify MRI features associated with appendicitis. Features expected to be associated with appendicitis were recorded in consensus by two expert radiologists on 223 abdominal MRIs in patients with suspected appendicitis. Nine MRI features were studied: appendix diameter >7 mm, appendicolith,

  4. Hong Kong English: phonological features

    OpenAIRE

    Irina-Ana Drobot

    2008-01-01

    The aim of the paper is to present phonological features of Hong Kong English, which is a variety of New English. I examine features of the sound system (vowel and consonantal systems), characteristics of stress, rhythm, intonation, and phonological processes of the English spoken by Hongkongers. The way in which the accent and characteristics of the Hong Kong variety of English differs from standard, RP English is pointed out. Influences of Chinese and Cantonese on the phonological features ...

  5. Cascaded face alignment via intimacy definition feature

    Science.gov (United States)

    Li, Hailiang; Lam, Kin-Man; Chiu, Man-Yau; Wu, Kangheng; Lei, Zhibin

    2017-09-01

    Recent years have witnessed the emerging popularity of regression-based face aligners, which directly learn mappings between facial appearance and shape-increment manifolds. We propose a random-forest based, cascaded regression model for face alignment by using a locally lightweight feature, namely intimacy definition feature. This feature is more discriminative than the pose-indexed feature, more efficient than the histogram of oriented gradients feature and the scale-invariant feature transform feature, and more compact than the local binary feature (LBF). Experimental validation of our algorithm shows that our approach achieves state-of-the-art performance when testing on some challenging datasets. Compared with the LBF-based algorithm, our method achieves about twice the speed, 20% improvement in terms of alignment accuracy and saves an order of magnitude on memory requirement.

  6. Extract the Relational Information of Static Features and Motion Features for Human Activities Recognition in Videos

    Directory of Open Access Journals (Sweden)

    Li Yao

    2016-01-01

    Full Text Available Both static features and motion features have shown promising performance in human activities recognition task. However, the information included in these features is insufficient for complex human activities. In this paper, we propose extracting relational information of static features and motion features for human activities recognition. The videos are represented by a classical Bag-of-Word (BoW model which is useful in many works. To get a compact and discriminative codebook with small dimension, we employ the divisive algorithm based on KL-divergence to reconstruct the codebook. After that, to further capture strong relational information, we construct a bipartite graph to model the relationship between words of different feature set. Then we use a k-way partition to create a new codebook in which similar words are getting together. With this new codebook, videos can be represented by a new BoW vector with strong relational information. Moreover, we propose a method to compute new clusters from the divisive algorithm’s projective function. We test our work on the several datasets and obtain very promising results.

  7. Temporal feature integration for music genre classification

    DEFF Research Database (Denmark)

    Meng, Anders; Ahrendt, Peter; Larsen, Jan

    2007-01-01

    , but they capture neither the temporal dynamics nor dependencies among the individual feature dimensions. Here, a multivariate autoregressive feature model is proposed to solve this problem for music genre classification. This model gives two different feature sets, the diagonal autoregressive (DAR......) and multivariate autoregressive (MAR) features which are compared against the baseline mean-variance as well as two other temporal feature integration techniques. Reproducibility in performance ranking of temporal feature integration methods were demonstrated using two data sets with five and eleven music genres...

  8. Inflation and WMAP three year data. Features have a feature.

    Energy Technology Data Exchange (ETDEWEB)

    Covi, L.; Hamann, J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Melchiorri, A. [INFN, Roma (Italy)]|[Rome-3 Univ. (Italy). Dipt. di Fisica; Slosar, A. [Ljubljana Univ. (Slovenia). Faculty of Mathematics and Physics; Sorbera, I. [Rome-3 Univ. (Italy). Dipt. di Fisica

    2006-06-15

    The new three year WMAP data seem to confirm the presence of non-standard large scale features in the Cosmic Microwave Anisotropies power spectrum. While these features may hint at uncorrected experimental systematics, it is also possible to generate, in a cosmological way, oscillations on large angular scales by introducing a sharp step in the inflaton potential. Using current cosmological data, we derive constraints on the position, magnitude and gradient of a possible step in the inflaton potential. We show that a step in the potential, while strongly constrained by current data, is still allowed and may provide an interesting explanation to the currently measured deviations from the standard featureless spectrum. (Orig.)

  9. Feature singletons attract spatial attention independently of feature priming.

    Science.gov (United States)

    Yashar, Amit; White, Alex L; Fang, Wanghaoming; Carrasco, Marisa

    2017-08-01

    People perform better in visual search when the target feature repeats across trials (intertrial feature priming [IFP]). Here, we investigated whether repetition of a feature singleton's color modulates stimulus-driven shifts of spatial attention by presenting a probe stimulus immediately after each singleton display. The task alternated every two trials between a probe discrimination task and a singleton search task. We measured both stimulus-driven spatial attention (via the distance between the probe and singleton) and IFP (via repetition of the singleton's color). Color repetition facilitated search performance (IFP effect) when the set size was small. When the probe appeared at the singleton's location, performance was better than at the opposite location (stimulus-driven attention effect). The magnitude of this attention effect increased with the singleton's set size (which increases its saliency) but did not depend on whether the singleton's color repeated across trials, even when the previous singleton had been attended as a search target. Thus, our findings show that repetition of a salient singleton's color affects performance when the singleton is task relevant and voluntarily attended (as in search trials). However, color repetition does not affect performance when the singleton becomes irrelevant to the current task, even though the singleton does capture attention (as in probe trials). Therefore, color repetition per se does not make a singleton more salient for stimulus-driven attention. Rather, we suggest that IFP requires voluntary selection of color singletons in each consecutive trial.

  10. short communication simple grinding-induced reactions of 2 ...

    African Journals Online (AJOL)

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    benzoxazine moiety features in the natural product terresoxazine isolated from Tribulus terrestris [12] and many other bioactive molecules [13-15]. Although several methods for the preparation of 1,3-oxazine derivatives have previously been reported [16-21] few have been focused on the solid-solid or solid-liquid grinding ...

  11. Synthesis of Stable and Soluble One-Handed Helical Homopoly(substituted acetylenes without the Coexistence of Any Other Chiral Moieties via Two-Step Polymer Reactions in Membrane State: Molecular Design of the Starting Monomer

    Directory of Open Access Journals (Sweden)

    Takashi Kaneko

    2012-01-01

    Full Text Available A soluble and stable one-handed helical poly(substituted phenylacetylene without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer followed by two-step polymer reactions in membrane state: (1 removing the chiral groups (desubstitution; and (2 introduction of achiral long alkyl groups at the same position as the desubstitution to enhance the solubility of the resulting one-handed helical polymer (resubstitution. The starting chiral monomer should have four characteristic substituents: (i a chiral group bonded to an easily hydrolyzed spacer group; (ii two hydroxyl groups; (iii a long rigid hydrophobic spacer between the chiral group and the polymerizing group; (iv a long achiral group near the chiral group. As spacer group a carbonate ester was selected. The two hydroxyl groups formed intramolecular hydrogen bonds stabilizing a one-handed helical structure in solution before and after the two-step polymer reactions in membrane state. The rigid long hydrophobic spacer, a phenylethynylphenyl group, enhanced the solubility of the starting polymer, and realized effective chiral induction from the chiral side groups to the main chain in the asymmetric-induced polymerization. The long alkyl group near the chiral group avoided shrinkage of the membrane and kept the reactivity of resubstitution in membrane state after removing the chiral groups. The g value (g = ([θ]/3,300/ε for the CD signal assigned to the main chain in the obtained final polymer was almost the same as that of the starting polymer in spite of the absence of any other chiral moieties. Moreover, since the one-handed helical structure was maintained by the intramolecular hydrogen bonds in a solution, direct observation of the one-handed helicity of the final homopolymer has been realized in CD for the solution for the first time.

  12. MRI features associated with acute appendicitis

    Energy Technology Data Exchange (ETDEWEB)

    Leeuwenburgh, Marjolein M.N. [University of Amsterdam, Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology (G1-223.1), Amsterdam (Netherlands); Jensch, Sebastiaan [Sint Lucas Andreas Hospital, Department of Radiology, Amsterdam (Netherlands); Gratama, Jan W.C. [Gelre Hospitals, Department of Radiology, Apeldoorn (Netherlands); Spilt, Aart [Kennemer Gasthuis, Department of Radiology, Haarlem (Netherlands); Wiarda, Bart M. [Alkmaar Medical Center, Department of Radiology, Alkmaar (Netherlands); Es, H.W. van [Sint Antonius Hospital, Department of Radiology, Nieuwegein (Netherlands); Cobben, Lodewijk P.J. [Haaglanden Medical Center, Department of Radiology, Leidschendam (Netherlands); Bossuyt, Patrick M.M. [University of Amsterdam, Department of Clinical Epidemiology, Academic Medical Center, Amsterdam (Netherlands); Boermeester, Marja A. [University of Amsterdam, Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); Stoker, Jaap [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Collaboration: on behalf of the OPTIMAP study group

    2014-01-15

    To identify MRI features associated with appendicitis. Features expected to be associated with appendicitis were recorded in consensus by two expert radiologists on 223 abdominal MRIs in patients with suspected appendicitis. Nine MRI features were studied: appendix diameter >7 mm, appendicolith, peri-appendiceal fat infiltration, peri-appendiceal fluid, absence of gas in the appendix, appendiceal wall destruction, restricted diffusion of the appendiceal wall, lumen or focal fluid collections. Appendicitis was assigned as the final diagnosis in 117/223 patients. Associations between imaging features and appendicitis were evaluated with logistic regression analysis. All investigated features were significantly associated with appendicitis in univariate analysis. Combinations of two and three features were associated with a probability of appendicitis of 88 % and 92 %, respectively. In patients without any of the nine features, appendicitis was present in 2 % of cases. After multivariate analysis, only an appendix diameter >7 mm, peri-appendiceal fat infiltration and restricted diffusion of the appendiceal wall were significantly associated with appendicitis. The probability of appendicitis was 96 % in their presence and 2 % in their absence. An appendix diameter >7 mm, peri-appendiceal fat infiltration and restricted diffusion of the appendiceal wall have the strongest association with appendicitis on MRI. (orig.)

  13. MRI features associated with acute appendicitis

    International Nuclear Information System (INIS)

    Leeuwenburgh, Marjolein M.N.; Jensch, Sebastiaan; Gratama, Jan W.C.; Spilt, Aart; Wiarda, Bart M.; Es, H.W. van; Cobben, Lodewijk P.J.; Bossuyt, Patrick M.M.; Boermeester, Marja A.; Stoker, Jaap

    2014-01-01

    To identify MRI features associated with appendicitis. Features expected to be associated with appendicitis were recorded in consensus by two expert radiologists on 223 abdominal MRIs in patients with suspected appendicitis. Nine MRI features were studied: appendix diameter >7 mm, appendicolith, peri-appendiceal fat infiltration, peri-appendiceal fluid, absence of gas in the appendix, appendiceal wall destruction, restricted diffusion of the appendiceal wall, lumen or focal fluid collections. Appendicitis was assigned as the final diagnosis in 117/223 patients. Associations between imaging features and appendicitis were evaluated with logistic regression analysis. All investigated features were significantly associated with appendicitis in univariate analysis. Combinations of two and three features were associated with a probability of appendicitis of 88 % and 92 %, respectively. In patients without any of the nine features, appendicitis was present in 2 % of cases. After multivariate analysis, only an appendix diameter >7 mm, peri-appendiceal fat infiltration and restricted diffusion of the appendiceal wall were significantly associated with appendicitis. The probability of appendicitis was 96 % in their presence and 2 % in their absence. An appendix diameter >7 mm, peri-appendiceal fat infiltration and restricted diffusion of the appendiceal wall have the strongest association with appendicitis on MRI. (orig.)

  14. Textural features for radar image analysis

    Science.gov (United States)

    Shanmugan, K. S.; Narayanan, V.; Frost, V. S.; Stiles, J. A.; Holtzman, J. C.

    1981-01-01

    Texture is seen as an important spatial feature useful for identifying objects or regions of interest in an image. While textural features have been widely used in analyzing a variety of photographic images, they have not been used in processing radar images. A procedure for extracting a set of textural features for characterizing small areas in radar images is presented, and it is shown that these features can be used in classifying segments of radar images corresponding to different geological formations.

  15. New carbocyclic N(6)-substituted adenine and pyrimidine nucleoside analogues with a bicyclo[2.2.1]heptane fragment as sugar moiety; synthesis, antiviral, anticancer activity and X-ray crystallography.

    Science.gov (United States)

    Tănase, Constantin I; Drăghici, Constantin; Cojocaru, Ana; Galochkina, Anastasia V; Orshanskaya, Jana R; Zarubaev, Vladimir V; Shova, Sergiu; Enache, Cristian; Maganu, Maria

    2015-10-01

    New nucleoside analogues with an optically active bicyclo[2.2.1]heptane skeleton as sugar moiety and 6-substituted adenine were synthesized by alkylation of 6-chloropurine intermediate. Thymine and uracil analogs were synthesized by building the pyrimidine ring on amine 1. X-ray crystallography confirmed an exo-coupling of the thymine to the ring and an L configuration of the nucleoside analogue. The library of compounds was tested for their inhibitory activity against influenza virus A∖California/07/09 (H1N1)pdm09 and coxsackievirus B4 in cell culture. Compounds 13a and 13d are the most promising for their antiviral activity against influenza, and compound 3c against coxsackievirus B4. Compounds 3b and 3g were tested for anticancer activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Excitation energy deactivation funnel in 3-substituted BODIPY-porphyrin conjugate

    International Nuclear Information System (INIS)

    Nguyen, Nguyen Tran; Verbelen, Bram; Leen, Volker; Waelkens, Etienne; Dehaen, Wim; Kruk, Mikalai

    2016-01-01

    BODIPYs absorb in the visible region which is complementary to that of porphyrins and therefore can be suggested as promising antenna groups to improve the light-harvesting potential of porphyrins. A boron-dipyrromethene dye was combined at the 3-position with a Zn-porphyrin to afford a conjugate. The fluorescence of the conjugate was found to originate from the BODIPY moiety independently of the excitation wavelength due to an unique set of energy transfer rates between the BODIPY and Zn-porphyrin moieties. The fluorescence intensity was shown to be tunable over a wide range using the solvent properties. This feature makes the studied BODIPY-porphyrin conjugate a promising compound for the design of new photochromic devices.

  17. Excitation energy deactivation funnel in 3-substituted BODIPY-porphyrin conjugate

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Nguyen Tran [Chemistry Department, University of Education, The University of DaNang, Ton Duc Thang 459, Da Nang (Viet Nam); Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven (Belgium); Verbelen, Bram; Leen, Volker [Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven (Belgium); Waelkens, Etienne [Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, Box 901, 3000 Leuven (Belgium); Dehaen, Wim, E-mail: wim.dehaen@kuleuven.be [Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven (Belgium); Kruk, Mikalai, E-mail: m.kruk@belstu.by [Belarusian State Technological University, Physics Department, Sverdlov Str., 13a, Minsk 220006 (Belarus)

    2016-11-15

    BODIPYs absorb in the visible region which is complementary to that of porphyrins and therefore can be suggested as promising antenna groups to improve the light-harvesting potential of porphyrins. A boron-dipyrromethene dye was combined at the 3-position with a Zn-porphyrin to afford a conjugate. The fluorescence of the conjugate was found to originate from the BODIPY moiety independently of the excitation wavelength due to an unique set of energy transfer rates between the BODIPY and Zn-porphyrin moieties. The fluorescence intensity was shown to be tunable over a wide range using the solvent properties. This feature makes the studied BODIPY-porphyrin conjugate a promising compound for the design of new photochromic devices.

  18. Conjunctive Coding of Complex Object Features

    Science.gov (United States)

    Erez, Jonathan; Cusack, Rhodri; Kendall, William; Barense, Morgan D.

    2016-01-01

    Critical to perceiving an object is the ability to bind its constituent features into a cohesive representation, yet the manner by which the visual system integrates object features to yield a unified percept remains unknown. Here, we present a novel application of multivoxel pattern analysis of neuroimaging data that allows a direct investigation of whether neural representations integrate object features into a whole that is different from the sum of its parts. We found that patterns of activity throughout the ventral visual stream (VVS), extending anteriorly into the perirhinal cortex (PRC), discriminated between the same features combined into different objects. Despite this sensitivity to the unique conjunctions of features comprising objects, activity in regions of the VVS, again extending into the PRC, was invariant to the viewpoints from which the conjunctions were presented. These results suggest that the manner in which our visual system processes complex objects depends on the explicit coding of the conjunctions of features comprising them. PMID:25921583

  19. Hong Kong English: phonological features

    Directory of Open Access Journals (Sweden)

    Irina-Ana Drobot

    2008-01-01

    Full Text Available The aim of the paper is to present phonological features of Hong Kong English, which is a variety of New English. I examine features of the sound system (vowel and consonantal systems, characteristics of stress, rhythm, intonation, and phonological processes of the English spoken by Hongkongers. The way in which the accent and characteristics of the Hong Kong variety of English differs from standard, RP English is pointed out. Influences of Chinese and Cantonese on the phonological features of Hong Kong English are noticeable

  20. Personality Features of Motorists

    Directory of Open Access Journals (Sweden)

    Andrej Justinek

    1997-12-01

    Full Text Available Justinek tries to answer the question whether or not motorists have specific personality features which predispose them for safe and well-mannered driving. A good driver should have sensory abilities which enable psycho-motor coordiation of a vehicle, intellectual and cognitive features that are important for solving problems in new, unknown situations, and emotional and motivational trails defining a driver's maturity. Justmek advocates the belief that in training future drivers greater attention should be paid to developing these features which are vital for safe driving and appropriate behaviour of drivers in traffic. He also suggests certain learning methods leading to development of the above­ mentioned personality traits. Justinek introduces the notion of the 'philosophy of driving' as an essential educational category in training future drivers.

  1. Features for detecting smoke in laparoscopic videos

    Directory of Open Access Journals (Sweden)

    Jalal Nour Aldeen

    2017-09-01

    Full Text Available Video-based smoke detection in laparoscopic surgery has different potential applications, such as the automatic addressing of surgical events associated with the electrocauterization task and the development of automatic smoke removal. In the literature, video-based smoke detection has been studied widely for fire surveillance systems. Nevertheless, the proposed methods are insufficient for smoke detection in laparoscopic videos because they often depend on assumptions which rarely hold in laparoscopic surgery such as static camera. In this paper, ten visual features based on motion, texture and colour of smoke are proposed and evaluated for smoke detection in laparoscopic videos. These features are RGB channels, energy-based feature, texture features based on gray level co-occurrence matrix (GLCM, HSV colour space feature, features based on the detection of moving regions using optical flow and the smoke colour in HSV colour space. These features were tested on four laparoscopic cholecystectomy videos. Experimental observations show that each feature can provide valuable information in performing the smoke detection task. However, each feature has weaknesses to detect the presence of smoke in some cases. By combining all proposed features smoke with high and even low density can be identified robustly and the classification accuracy increases significantly.

  2. Novel Features for Brain-Computer Interfaces

    Science.gov (United States)

    Woon, W. L.; Cichocki, A.

    2007-01-01

    While conventional approaches of BCI feature extraction are based on the power spectrum, we have tried using nonlinear features for classifying BCI data. In this paper, we report our test results and findings, which indicate that the proposed method is a potentially useful addition to current feature extraction techniques. PMID:18364991

  3. Feature Binding in Zebrafish

    Directory of Open Access Journals (Sweden)

    P Neri

    2012-07-01

    Full Text Available Binding operations are primarily ascribed to cortex or similarly complex avian structures. My experiments show that the zebrafish, a lower vertebrate lacking cortex, supports visual feature binding of form and motion for the purpose of social behavior. These results challenge the notion that feature binding may require highly evolved neural structures and demonstrate that the nervous system of lower vertebrates can afford unexpectedly complex computations.

  4. 1.45 A resolution crystal structure of recombinant PNP in complex with a pM multisubstrate analogue inhibitor bearing one feature of the postulated transition state

    International Nuclear Information System (INIS)

    Chojnowski, Grzegorz; Breer, Katarzyna; Narczyk, Marta; Wielgus-Kutrowska, Beata; Czapinska, Honorata; Hashimoto, Mariko; Hikishima, Sadao; Yokomatsu, Tsutomu; Bochtler, Matthias; Girstun, Agnieszka; Staron, Krzysztof; Bzowska, Agnieszka

    2010-01-01

    Low molecular mass purine nucleoside phosphorylases (PNPs, E.C. 2.4.2.1) are homotrimeric enzymes that are tightly inhibited by immucillins. Due to the positive charge on the ribose like part (iminoribitol moiety) and protonation of the N7 atom of the purine ring, immucillins are believed to act as transition state analogues. Over a wide range of concentrations, immucillins bind with strong negative cooperativity to PNPs, so that only every third binding site of the enzyme is occupied (third-of-the-sites binding). 9-(5',5'-difluoro-5'-phosphonopentyl)-9-deazaguanine (DFPP-DG) shares with immucillins the protonation of the N7, but not the positive charge on the ribose like part of the molecule. We have previously shown that DFPP-DG interacts with PNPs with subnanomolar inhibition constant. Here, we report additional biochemical experiments to demonstrate that the inhibitor can be bound with the same K d (∼190 pM) to all three substrate binding sites of the trimeric PNP, and a crystal structure of PNP in complex with DFPP-DG at 1.45 A resolution, the highest resolution published for PNPs so far. The crystals contain the full PNP homotrimer in the asymmetric unit. DFPP-DG molecules are bound in superimposable manner and with full occupancies to all three PNP subunits. Thus the postulated third-of-the-sites binding of immucillins should be rather attribute to the second feature of the transition state, ribooxocarbenium ion character of the ligand or to the coexistence of both features characteristic for the transition state. The DFPP-DG/PNP complex structure confirms the earlier observations, that the loop from Pro57 to Gly66 covering the phosphate-binding site cannot be stabilized by phosphonate analogues. The loop from Glu250 to Gln266 covering the base-binding site is organized by the interactions of Asn243 with the Hoogsteen edge of the purine base of analogues bearing one feature of the postulated transition state (protonated N7 position).

  5. A molecular hybrid polyoxometalate-organometallic moieties and its relevance to supercapacitors in physiological electrolytes

    Science.gov (United States)

    Chinnathambi, Selvaraj; Ammam, Malika

    2015-06-01

    Supercapacitors operating in physiological electrolytes are of great relevance for both their environmentally friendly aspect as well as the possibility to be employed for powering implantable microelectronic devices using directly biological fluids as electrolytes. Polyoxometalate (POMs) have been proven to be useful for supercapacitors in acidic media. However, in neutral pH, POMs are usually not stable. One relevant alternative is to stabilize POMs by pairing them with organic moieties to form hybrids. In this study, we combined K6P2Mo18O62·12H2O (P2Mo18) with Ru(bpy)3Cl2.6H2O (Ru(bpy)). The synthesis was carried out with and without the mild reducing agent KI. The hybrids were characterized by CHN analysis, TEM, FT-IR, XRD, TGA and cyclic voltammetry. CHN elemental analysis revealed that one mole [P2Mo18O62]6- is paired with 3 mol [Ru(bpy)3]2+ to form [Ru(bpy)3]3PMo18O62·nH2O. With KI present, [P2Mo18O62]6- is linked to 3.33 mol to yield [Ru(bpy)3]3.33PMo18O62·mH2O. Excess of Ru(bpy) in [Ru(bpy)3]3.33PMo18O62·mH2O was further confirmed by TEM, FT-IR, XRD, TGA and cyclic voltammetry. In turn, hybrid composition is found to strongly influence the supercapacitor behavior. The hybrid rich in Ru(bpy) is found to perform better for supercapacitors in physiological electrolytes. 125 F g-1 and 68 F g-1 are the capacitance values obtained with [Ru(bpy)3]3.33PMo18O62·mH2O and [Ru(bpy)3]3PMo18O62·nH2O, respectively. In terms of specific energy densities, 3.5 Wh kg-1 and 2 Wh kg-1 were obtained for both hybrid simultaneously. The difference in supercapacitor performance between both hybrids is also noticed in impedance spectroscopy which showed that [Ru(bpy)3]3.33PMo18O62·mH2O has lower electron transfer resistance if compared to [Ru(bpy)3]3PMo18O62·nH2O. Finally, if compared of parent K6P2Mo18O62·12H2O, the stability of both hybrids is found to be highly improved.

  6. Ontology patterns for complex topographic feature yypes

    Science.gov (United States)

    Varanka, Dalia E.

    2011-01-01

    Complex feature types are defined as integrated relations between basic features for a shared meaning or concept. The shared semantic concept is difficult to define in commonly used geographic information systems (GIS) and remote sensing technologies. The role of spatial relations between complex feature parts was recognized in early GIS literature, but had limited representation in the feature or coverage data models of GIS. Spatial relations are more explicitly specified in semantic technology. In this paper, semantics for topographic feature ontology design patterns (ODP) are developed as data models for the representation of complex features. In the context of topographic processes, component assemblages are supported by resource systems and are found on local landscapes. The topographic ontology is organized across six thematic modules that can account for basic feature types, resource systems, and landscape types. Types of complex feature attributes include location, generative processes and physical description. Node/edge networks model standard spatial relations and relations specific to topographic science to represent complex features. To demonstrate these concepts, data from The National Map of the U. S. Geological Survey was converted and assembled into ODP.

  7. Feature-level domain adaptation

    DEFF Research Database (Denmark)

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

    2016-01-01

    -level domain adaptation (flda), that models the dependence between the two domains by means of a feature-level transfer model that is trained to describe the transfer from source to target domain. Subsequently, we train a domain-adapted classifier by minimizing the expected loss under the resulting transfer...... modeled via a dropout distribution, which allows the classiffier to adapt to differences in the marginal probability of features in the source and the target domain. Our experiments on several real-world problems show that flda performs on par with state-of-the-art domainadaptation techniques.......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...

  8. Addressing scalability while feature requests persist. A look at NASA Worldview's new features and their implementation.

    Science.gov (United States)

    King, B. A.

    2017-12-01

    Worldview is a high-traffic web mapping application created using the JavaScript mapping library, OpenLayers. This presentation will primarily focus on three new features: A wrapping component that seamlessly shows satellite imagery over the dateline where most maps either stop or wrap the imagery of the same date. An animation feature that allows users to select date ranges over which they can animate. An A/B comparison feature that gives users the power to compare imagery between dates and layers. In response to an increasingly large codebase caused by ongoing feature requests, Worldview is transitioning to a smaller core codebase comprised of external reusable modules. When creating a module with the intention of having someone else reuse it for a different task, one inherently starts generating code that is easier to read and easier to maintain. This presentation will show demos of these features and cover development techniques used to create them.

  9. Light field morphing using 2D features.

    Science.gov (United States)

    Wang, Lifeng; Lin, Stephen; Lee, Seungyong; Guo, Baining; Shum, Heung-Yeung

    2005-01-01

    We present a 2D feature-based technique for morphing 3D objects represented by light fields. Existing light field morphing methods require the user to specify corresponding 3D feature elements to guide morph computation. Since slight errors in 3D specification can lead to significant morphing artifacts, we propose a scheme based on 2D feature elements that is less sensitive to imprecise marking of features. First, 2D features are specified by the user in a number of key views in the source and target light fields. Then the two light fields are warped view by view as guided by the corresponding 2D features. Finally, the two warped light fields are blended together to yield the desired light field morph. Two key issues in light field morphing are feature specification and warping of light field rays. For feature specification, we introduce a user interface for delineating 2D features in key views of a light field, which are automatically interpolated to other views. For ray warping, we describe a 2D technique that accounts for visibility changes and present a comparison to the ideal morphing of light fields. Light field morphing based on 2D features makes it simple to incorporate previous image morphing techniques such as nonuniform blending, as well as to morph between an image and a light field.

  10. Pyrones to pyrans: enantioselective radical additions to acyloxy pyrones.

    Science.gov (United States)

    Sibi, Mukund P; Zimmerman, Jake

    2006-10-18

    This paper describes a highly site-, diastereo-, and enantioselective intermolecular radical addition/hydrogen atom transfer to hydroxypyrone pyromeconic and kojic acids. The methodology can be extended to the formation of chiral quaternary centers. The products obtained are densely functionalized pyran moieties. The products contain structural features amenable for the introduction of additional substituents.

  11. Nonmotor Features in Atypical Parkinsonism.

    Science.gov (United States)

    Bhatia, Kailash P; Stamelou, Maria

    2017-01-01

    Atypical parkinsonism (AP) comprises mainly multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD), which are distinct pathological entities, presenting with a wide phenotypic spectrum. The classic syndromes are now called MSA-parkinsonism (MSA-P), MSA-cerebellar type (MSA-C), Richardson's syndrome, and corticobasal syndrome. Nonmotor features in AP have been recognized almost since the initial description of these disorders; however, research has been limited. Autonomic dysfunction is the most prominent nonmotor feature of MSA, but also gastrointestinal symptoms, sleep dysfunction, and pain, can be a feature. In PSP and CBD, the most prominent nonmotor symptoms comprise those deriving from the cognitive/neuropsychiatric domain. Apart from assisting the clinician in the differential diagnosis with Parkinson's disease, nonmotor features in AP have a big impact on quality of life and prognosis of AP and their treatment poses a major challenge for clinicians. © 2017 Elsevier Inc. All rights reserved.

  12. Wilson’s disease: Atypical imaging features

    Directory of Open Access Journals (Sweden)

    Venugopalan Y Vishnu

    2016-10-01

    Full Text Available Wilson’s disease is a genetic movement disorder with characteristic clinical and imaging features. We report a 17- year-old boy who presented with sialorrhea, hypophonic speech, paraparesis with repeated falls and recurrent seizures along with cognitive decline. He had bilateral Kayser Flescher rings. Other than the typical features of Wilson’s disease in cranial MRI, there were extensive white matter signal abnormalities (T2 and FLAIR hyperintensities and gyriform contrast enhancement which are rare imaging features in Wilson's disease. A high index of suspicion is required to diagnose Wilson’s disease when atypical imaging features are present.

  13. Multimodal Feature Learning for Video Captioning

    Directory of Open Access Journals (Sweden)

    Sujin Lee

    2018-01-01

    Full Text Available Video captioning refers to the task of generating a natural language sentence that explains the content of the input video clips. This study proposes a deep neural network model for effective video captioning. Apart from visual features, the proposed model learns additionally semantic features that describe the video content effectively. In our model, visual features of the input video are extracted using convolutional neural networks such as C3D and ResNet, while semantic features are obtained using recurrent neural networks such as LSTM. In addition, our model includes an attention-based caption generation network to generate the correct natural language captions based on the multimodal video feature sequences. Various experiments, conducted with the two large benchmark datasets, Microsoft Video Description (MSVD and Microsoft Research Video-to-Text (MSR-VTT, demonstrate the performance of the proposed model.

  14. Language identification using excitation source features

    CERN Document Server

    Rao, K Sreenivasa

    2015-01-01

    This book discusses the contribution of excitation source information in discriminating language. The authors focus on the excitation source component of speech for enhancement of language identification (LID) performance. Language specific features are extracted using two different modes: (i) Implicit processing of linear prediction (LP) residual and (ii) Explicit parameterization of linear prediction residual. The book discusses how in implicit processing approach, excitation source features are derived from LP residual, Hilbert envelope (magnitude) of LP residual and Phase of LP residual; and in explicit parameterization approach, LP residual signal is processed in spectral domain to extract the relevant language specific features. The authors further extract source features from these modes, which are combined for enhancing the performance of LID systems. The proposed excitation source features are also investigated for LID in background noisy environments. Each chapter of this book provides the motivatio...

  15. Guilt by Association: The 13 Micron Dust Emission Feature and Its Correlation to Other Gas and Dust Features

    Science.gov (United States)

    Sloan, G. C.; Kraemer, Kathleen E.; Goebel, J. H.; Price, Stephan D.

    2003-09-01

    A study of all full-scan spectra of optically thin oxygen-rich circumstellar dust shells in the database produced by the Short Wavelength Spectrometer on ISO reveals that the strength of several infrared spectral features correlates with the strength of the 13 μm dust feature. These correlated features include dust features at 19.8 and 28.1 μm and the bands produced by warm carbon dioxide molecules (the strongest of which are at 13.9, 15.0, and 16.2 μm). The database does not provide any evidence for a correlation of the 13 μm feature with a dust feature at 32 μm, and it is more likely that a weak emission feature at 16.8 μm arises from carbon dioxide gas rather than dust. The correlated dust features at 13, 20, and 28 μm tend to be stronger with respect to the total dust emission in semiregular and irregular variables associated with the asymptotic giant branch than in Mira variables or supergiants. This family of dust features also tends to be stronger in systems with lower infrared excesses and thus lower mass-loss rates. We hypothesize that the dust features arise from crystalline forms of alumina (13 μm) and silicates (20 and 28 μm). Based on observations with the ISO, a European Space Agency (ESA) project with instruments funded by ESA member states (especially the Principal Investigator countries: France, Germany, the Netherlands, and the United Kingdom) and with the participation of the Institute of Space and Astronautical Science (ISAS) and the National Aeronautics and Space Administration (NASA).

  16. Oxidation of cholesterol moiety of low density lipoprotein in the presence of human endothelial cells or Cu+2 ions: identification of major products and their effects.

    Science.gov (United States)

    Bhadra, S; Arshad, M A; Rymaszewski, Z; Norman, E; Wherley, R; Subbiah, M T

    1991-04-15

    Oxidation of lipoproteins is believed to play a key role in atherogenesis. In this study, low density lipoproteins (LDL) was subjected to oxidation in the presence of either human umbilical vein endothelial cells or with Cu+2 ions and the major oxides formed were identified. While cholesterol-alpha-epoxide (C-alpha EP) was the major product of cholesterol peroxidation in the presence of endothelial cells, cholest-3,5-dien-7-one (CD) predominated in the presence of Cu+2 ion. Both steroids were identified by gas chromatography/mass spectrometry. HDL cholesterol was resistant to oxidation. When tested on human skin fibroblasts in culture C-alpha EP (10 micrograms/ml) caused marked stimulation of 14C-oleate incorporation into cholesterol esters, while CD stimulated cholesterol esterification only mildly. These studies show that a) C-alpha EP is the major peroxidation product of LDL cholesterol moiety in the presence of endothelial cells and b) it causes marked stimulation of cholesterol esterification in cells. C-alpha EP may play a key role in increasing cholesterol esterification noted in atherogenesis.

  17. Comparison of advanced mid-sized reactors regarding passive features, core damage frequencies and core melt retention features

    International Nuclear Information System (INIS)

    Wider, H.

    2005-01-01

    New Light Water Reactors, whose regular safety systems are complemented by passive safety systems, are ready for the market. The special aspect of passive safety features is their actuation and functioning independent of the operator. They add significantly to reduce the core damage frequency (CDF) since the operator continues to play its independent role in actuating the regular safety devices based on modern instrumentation and control (I and C). The latter also has passive features regarding the prevention of accidents. Two reactors with significant passive features that are presently offered on the market are the AP1000 PWR and the SWR 1000 BWR. Their passive features are compared and also their core damage frequencies (CDF). The latter are also compared with those of a VVER-1000. A further discussion about the two passive plants concerns their mitigating features for severe accidents. Regarding core-melt retention both rely on in-vessel cooling of the melt. The new VVER-1000 reactor, on the other hand features a validated ex-vessel concept. (author)

  18. Release of the cyano moiety in the crystal structure of N-cyanomethyl-N-(2-methoxyethyl)-daunomycin complexed with d(CGATCG).

    Science.gov (United States)

    Saminadin, P; Dautant, A; Mondon, M; Langlois D'estaintot, B; Courseille, C; Précigoux, G

    2000-01-01

    Doxorubicin is among the most widely used anthracycline in cancer chemotherapy. In an attempt to avoid the cardiotoxicity and drug resistance of doxorubicin therapy, several analogues were synthesized. The cyanomorpholinyl derivative is the most cytotoxic. They differ greatly from their parent compound in their biological and pharmacological properties, inducing cross-links in drug DNA complexes. The present study concerns N-cyanomethyl-N-(2-methoxyethyl)-daunomycin (CMDa), a synthetic analogue of cyanomorpholino-daunomycin. Compared to doxorubicin, CMDa displays a cytotoxic activity on L1210 leukemia cells at higher concentration but is effective on doxorubicin resistant cells. The results of fluorescence quenching experiments as well as the melting temperature (DeltaTm = 7.5 degrees C) studies are consistent with a drug molecule which intercalates between the DNA base pairs and stabilizes the DNA double helix. The crystal structure of CMDa complexed to the hexanucleotide d(CGATCG) has been determined at 1.5 A resolution. The complex crystallizes in the space group P41212 and is similar to other anthracycline-hexanucleotide complexes. In the crystal state, the observed densities indicate the formation of N-hydroxymethyl-N-(2-methoxyethyl)-daunomycin (HMDa) with the release of the cyano moiety without DNA alkylation. The formation of this degradation compound is discussed in relation with other drug modifications when binding to DNA. Comparison with two other drug-DNA crystal structures suggests a correlation between a slight change in DNA conformation and the nature of the amino sugar substituents at the N3' position located in the minor groove.

  19. Controllable edge feature sharpening for dental applications.

    Science.gov (United States)

    Fan, Ran; Jin, Xiaogang

    2014-01-01

    This paper presents a new approach to sharpen blurred edge features in scanned tooth preparation surfaces generated by structured-light scanners. It aims to efficiently enhance the edge features so that the embedded feature lines can be easily identified in dental CAD systems, and to avoid unnatural oversharpening geometry. We first separate the feature regions using graph-cut segmentation, which does not require a user-defined threshold. Then, we filter the face normal vectors to propagate the geometry from the smooth region to the feature region. In order to control the degree of the sharpness, we propose a feature distance measure which is based on normal tensor voting. Finally, the vertex positions are updated according to the modified face normal vectors. We have applied the approach to scanned tooth preparation models. The results show that the blurred edge features are enhanced without unnatural oversharpening geometry.

  20. Controllable Edge Feature Sharpening for Dental Applications

    Directory of Open Access Journals (Sweden)

    Ran Fan

    2014-01-01

    Full Text Available This paper presents a new approach to sharpen blurred edge features in scanned tooth preparation surfaces generated by structured-light scanners. It aims to efficiently enhance the edge features so that the embedded feature lines can be easily identified in dental CAD systems, and to avoid unnatural oversharpening geometry. We first separate the feature regions using graph-cut segmentation, which does not require a user-defined threshold. Then, we filter the face normal vectors to propagate the geometry from the smooth region to the feature region. In order to control the degree of the sharpness, we propose a feature distance measure which is based on normal tensor voting. Finally, the vertex positions are updated according to the modified face normal vectors. We have applied the approach to scanned tooth preparation models. The results show that the blurred edge features are enhanced without unnatural oversharpening geometry.

  1. FeatureMap3D - a tool to map protein features and sequence conservation onto homologous structures in the PDB

    DEFF Research Database (Denmark)

    Wernersson, Rasmus; Rapacki, Krzysztof; Stærfeldt, Hans Henrik

    2006-01-01

    FeatureMap3D is a web-based tool that maps protein features onto 3D structures. The user provides sequences annotated with any feature of interest, such as post-translational modifications, protease cleavage sites or exonic structure and FeatureMap3D will then search the Protein Data Bank (PDB) f...

  2. Glacial Features (Point) - Quad 168 (EPPING, NH)

    Data.gov (United States)

    University of New Hampshire — The Glacial Features (Point) layer describes point features associated with surficial geology. These glacial features include, but are not limited to, delta forsets,...

  3. Brain uptake and metabolism of the endocannabinoid anandamide labeled in either the arachidonoyl or ethanolamine moiety

    International Nuclear Information System (INIS)

    Hu, Kun; Sonti, Shilpa; Glaser, Sherrye T.; Duclos, Richard I.; Gatley, Samuel J.

    2017-01-01

    Introduction: Anandamide (N-arachidonoylethanolamine) is a retrograde neuromodulator that activates cannabinoid receptors. The concentration of anandamide in the brain is controlled by fatty acid amide hydrolase (FAAH), which has been the focus of recent drug discovery efforts. Previous studies in C57BL/6 mice using [ 3 H-arachidonoyl]anandamide demonstrated deposition of tritium in thalamus and cortical areas that was blocked by treatment with an FAAH inhibitor and that was not seen in FAAH-knockout mice. This suggested that long chain fatty acid amides radiolabeled in the fatty acid moiety might be useful as ex vivo and in vivo radiotracers for FAAH, since labeled fatty acid released by hydrolysis would be rapidly incorporated into phospholipids with long metabolic turnover periods. Methods: Radiotracers were administered intravenously to conscious Swiss–Webster mice, and radioactivity concentrations in brain areas was quantified and radiolabeled metabolites determined by radiochromatography. Results: [ 14 C]Arachidonic acid, [ 14 C-arachidonoyl]anandamide and [ 14 C-ethanolamine]anandamide, and also [ 14 C]myristic acid, [ 14 C-myristoyl]myristoylethanolamine and [ 14 C-ethanolamine]myristoyl-ethanolamine all had very similar distribution patterns, with whole brain radioactivity concentrations of 2–4% injected dose per gram. Pretreatment with the potent selective FAAH inhibitor URB597 did not significantly alter distribution patterns although radiochromatography demonstrated that the rate of incorporation of label from [ 14 C]anandamide into phospholipids was decreased. Pretreatment with the muscarinic agonist arecoline which increases cerebral perfusion increased brain uptake of radiolabel from [ 14 C]arachidonic acid and [ 14 C-ethanolamine]anandamide, and (in dual isotope studies) from the unrelated tracer [ 125 I]RTI-55. Conclusions: Together with our previously published study with [ 18 F-palmitoyl]16-fluoro-palmitoylethanolamine, the data show that the

  4. Partial Epilepsy with Auditory Features

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-07-01

    Full Text Available The clinical characteristics of 53 sporadic (S cases of idiopathic partial epilepsy with auditory features (IPEAF were analyzed and compared to previously reported familial (F cases of autosomal dominant partial epilepsy with auditory features (ADPEAF in a study at the University of Bologna, Italy.

  5. Feature Extraction Using Fractal Codes

    NARCIS (Netherlands)

    B.A.M. Schouten (Ben); P.M. de Zeeuw (Paul)

    1999-01-01

    htmlabstractFast and successful searching for an object in a multimedia database is a highly desirable functionality. Several approaches to content based retrieval for multimedia databases can be found in the literature [9,10,12,14,17]. The approach we consider is feature extraction. A feature can

  6. Remodularizing Java programs for comprehension of features

    DEFF Research Database (Denmark)

    Olszak, Andrzej; Jørgensen, Bo Nørregaard

    2009-01-01

    . In absence of these mechanisms, feature implementations tend to be scattered and tangled in terms of object-oriented abstractions, making the code implementing features difficult to locate and comprehend. In this paper we present a semi-automatic method for feature-oriented remodularization of Java programs....... Our method uses execution traces to locate implementations of features, and Java packages to establish explicit feature modules. To evaluate usefulness of the approach, we present a case study where we apply our method to two real-world software systems. The obtained results indicate a significant...

  7. Patch layout generation by detecting feature networks

    KAUST Repository

    Cao, Yuanhao

    2015-02-01

    The patch layout of 3D surfaces reveals the high-level geometric and topological structures. In this paper, we study the patch layout computation by detecting and enclosing feature loops on surfaces. We present a hybrid framework which combines several key ingredients, including feature detection, feature filtering, feature curve extension, patch subdivision and boundary smoothing. Our framework is able to compute patch layouts through concave features as previous approaches, but also able to generate nice layouts through smoothing regions. We demonstrate the effectiveness of our framework by comparing with the state-of-the-art methods.

  8. Feature coding for image representation and recognition

    CERN Document Server

    Huang, Yongzhen

    2015-01-01

    This brief presents a comprehensive introduction to feature coding, which serves as a key module for the typical object recognition pipeline. The text offers a rich blend of theory and practice while reflects the recent developments on feature coding, covering the following five aspects: (1) Review the state-of-the-art, analyzing the motivations and mathematical representations of various feature coding methods; (2) Explore how various feature coding algorithms evolve along years; (3) Summarize the main characteristics of typical feature coding algorithms and categorize them accordingly; (4) D

  9. Discovery of a novel acyl-CoA: cholesterol acyltransferase inhibitor: the synthesis, biological evaluation, and reduced adrenal toxicity of (4-phenylcoumarin)acetanilide derivatives with a carboxylic acid moiety.

    Science.gov (United States)

    Ogino, Masaki; Nakada, Yoshihisa; Negoro, Nobuyuki; Itokawa, Shigekazu; Nishimura, Satoshi; Sanada, Tsukasa; Satomi, Tomoko; Kita, Shunbun; Kubo, Kazuki; Marui, Shogo

    2011-01-01

    As a part of our research for novel potent and orally available acyl-CoA: cholesterol acyltransferase (ACAT) inhibitors that can be used as anti-atherosclerotic agents, we recently reported the discovery of the (4-phenylcoumarine)acetanilide derivative 1. However, compound 1 showed adrenal toxicity in animal models. In order to search for safer ACAT inhibitors that do not have adrenal toxicity, we examined the inhibitory activity of ACAT in human macrophage and adrenal cells. The introduction of a carboxylic acid moiety on the pendant phenyl ring and the adjustment of the lipophilicity led to the discovery of (2E)-3-[7-chloro-3-[2-[[4-fluoro-2-(trifluoromethyl)phenyl]amino]-2-oxoethyl]-6-methyl-2-oxo-2H-chromen-4-yl]phenyl]acrylic acid (21e), which showed potent ACAT inhibitory activity in macrophages and a selectivity of around 30-fold over adrenal cells. In addition, compound 21e showed high adrenal safety in guinea pigs.

  10. Currency features for visually impaired people

    Science.gov (United States)

    Hyland, Sandra L.; Legge, Gordon E.; Shannon, Robert R.; Baer, Norbert S.

    1996-03-01

    The estimated 3.7 million Americans with low vision experience a uniquely difficult task in identifying the denominations of U.S. banknotes because the notes are remarkably uniform in size, color, and general design. The National Research Council's Committee on Currency Features Usable by the Visually Impaired assessed features that could be used by people who are visually disabled to distinguish currency from other documents and to denominate and authenticate banknotes using available technology. Variation of length and height, introduction of large numerals on a uniform, high-contrast background, use of different colors for each of the six denominations printed, and the introduction of overt denomination codes that could lead to development of effective, low-cost devices for examining banknotes were all deemed features available now. Issues affecting performance, including the science of visual and tactile perception, were addressed for these features, as well as for those features requiring additional research and development. In this group the committee included durable tactile features such as those printed with transparent ink, and the production of currency with holes to indicate denomination. Among long-range approaches considered were the development of technologically advanced devices and smart money.

  11. Fall Detection Using Smartphone Audio Features.

    Science.gov (United States)

    Cheffena, Michael

    2016-07-01

    An automated fall detection system based on smartphone audio features is developed. The spectrogram, mel frequency cepstral coefficents (MFCCs), linear predictive coding (LPC), and matching pursuit (MP) features of different fall and no-fall sound events are extracted from experimental data. Based on the extracted audio features, four different machine learning classifiers: k-nearest neighbor classifier (k-NN), support vector machine (SVM), least squares method (LSM), and artificial neural network (ANN) are investigated for distinguishing between fall and no-fall events. For each audio feature, the performance of each classifier in terms of sensitivity, specificity, accuracy, and computational complexity is evaluated. The best performance is achieved using spectrogram features with ANN classifier with sensitivity, specificity, and accuracy all above 98%. The classifier also has acceptable computational requirement for training and testing. The system is applicable in home environments where the phone is placed in the vicinity of the user.

  12. Bio-Inspired Supramolecular Chemistry Provides Highly Concentrated Dispersions of Carbon Nanotubes in Polythiophene

    Directory of Open Access Journals (Sweden)

    Yen-Ting Lin

    2016-06-01

    Full Text Available In this paper we report the first observation, through X-ray diffraction, of noncovalent uracil–uracil (U–U dimeric π-stacking interactions in carbon nanotube (CNT–based supramolecular assemblies. The directionally oriented morphology determined using atomic force microscopy revealed highly organized behavior through π-stacking of U moieties in a U-functionalized CNT derivative (CNT–U. We developed a dispersion system to investigate the bio-inspired interactions between an adenine (A-terminated poly(3-adeninehexyl thiophene (PAT and CNT–U. These hybrid CNT–U/PAT materials interacted through π-stacking and multiple hydrogen bonding between the U moieties of CNT–U and the A moieties of PAT. Most importantly, the U···A multiple hydrogen bonding interactions between CNT–U and PAT enhanced the dispersion of CNT–U in a high-polarity solvent (DMSO. The morphology of these hybrids, determined using transmission electron microscopy, featured grape-like PAT bundles wrapped around the CNT–U surface; this tight connection was responsible for the enhanced dispersion of CNT–U in DMSO.

  13. Synthesis and evaluation of 8,4'-dideshydroxy-leinamycin revealing new insights into the structure-activity relationship of the anticancer natural product leinamycin.

    Science.gov (United States)

    Liu, Tao; Ma, Ming; Ge, Hui-Ming; Yang, Chunying; Cleveland, John; Shen, Ben

    2015-11-01

    Leinamycin (LNM, 1) is a novel antitumor antibiotic produced by Streptomyces atroolivaceus S-140 and features an unusual 1,3-dioxo-1,2-dithiolane moiety that is spiro-fused to a thiazole-containing 18-membered lactam ring. The 1,3-dioxo-1,2-dithiolane moiety of LNM is essential for its antitumor activity via an episulfonium ion-mediated DNA alkylation upon reductive activation in the presence of cellular thiols. We recently isolated leinamycin E1 (LNM E1, 2) from an engineered strain S. atroolivaceus SB3033, which lacks the 1,3-dioxo-1,2-dithiolane moiety. Here we report the chemical synthesis of 8,4'-dideshydroxy-LNM (5) from 2 and determination of the cytotoxicity of 5 against selected cancer cell lines in comparison with 1; 5 exhibits comparable activity as 1 with the EC50 values between 8.21 and 275 nM. This work reveals new insight into the structure-activity relationship of LNM and highlights the synergy between metabolic pathway engineering and medicinal chemistry for natural product drug discovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Flexible feature interface for multimedia sources

    Science.gov (United States)

    Coffland, Douglas R [Livermore, CA

    2009-06-09

    A flexible feature interface for multimedia sources system that includes a single interface for the addition of features and functions to multimedia sources and for accessing those features and functions from remote hosts. The interface utilizes the export statement: export "C" D11Export void FunctionName(int argc, char ** argv,char * result, SecureSession *ctrl) or the binary equivalent of the export statement.

  15. Prostatic adenocarcinoma with glomeruloid features.

    Science.gov (United States)

    Pacelli, A; Lopez-Beltran, A; Egan, A J; Bostwick, D G

    1998-05-01

    A wide variety of architectural patterns of adenocarcinoma may be seen in the prostate. We have recently encountered a hitherto-undescribed pattern of growth characterized by intraluminal ball-like clusters of cancer cells reminiscent of renal glomeruli, which we refer to as prostatic adenocarcinoma with glomeruloid features. To define the architectural features, frequency, and distribution of prostatic adenocarcinoma with glomeruloid features, we reviewed 202 totally embedded radical prostatectomy specimens obtained between October 1992 and April 1994 from the files of the Mayo Clinic. This series was supplemented by 100 consecutive needle biopsies with prostatic cancer from January to February 1996. Prostatic adenocarcinoma with glomeruloid features was characterized by round to oval epithelial tufts growing within malignant acini, often supported by a fibrovascular core. The epithelial cells were sometimes arranged in semicircular concentric rows separated by clefted spaces. In the radical prostatectomy specimens, nine cases (4.5%) had glomeruloid features. The glomeruloid pattern constituted 5% to 20% of each cancer (mean, 8.33%) and was usually located at the apex or in the peripheral zone of the prostate. Seven cases were associated with a high Gleason score (7 or 8), one with a score of 6, and one with a score of 5. All cases were associated with high-grade prostatic intraepithelial neoplasia and extensive perineural invasion. Pathological stages included T2c (three cases), T3b (four cases), and T3c (two cases); one of the T3b cases had lymph node metastases (N1). Three (3%) of 100 consecutive routine needle biopsy specimens with cancer showed glomeruloid features, and this pattern constituted 5% to 10% of each cancer (mean, 6.7%). The Gleason score was 6 for two cases and 8 for one case. Two cases were associated with high-grade prostatic intraepithelial neoplasia, and one case had perineural invasion. Glomeruloid features were not observed in any benign or

  16. Feature extraction using fractal codes

    NARCIS (Netherlands)

    B.A.M. Ben Schouten; Paul M. de Zeeuw

    1999-01-01

    Fast and successful searching for an object in a multimedia database is a highly desirable functionality. Several approaches to content based retrieval for multimedia databases can be found in the literature [9,10,12,14,17]. The approach we consider is feature extraction. A feature can be seen as a

  17. Iris recognition based on key image feature extraction.

    Science.gov (United States)

    Ren, X; Tian, Q; Zhang, J; Wu, S; Zeng, Y

    2008-01-01

    In iris recognition, feature extraction can be influenced by factors such as illumination and contrast, and thus the features extracted may be unreliable, which can cause a high rate of false results in iris pattern recognition. In order to obtain stable features, an algorithm was proposed in this paper to extract key features of a pattern from multiple images. The proposed algorithm built an iris feature template by extracting key features and performed iris identity enrolment. Simulation results showed that the selected key features have high recognition accuracy on the CASIA Iris Set, where both contrast and illumination variance exist.

  18. Vehicle barriers: emphasis on natural features

    International Nuclear Information System (INIS)

    Adams, K.G.; Roscoe, B.J.

    1985-07-01

    The recent increase in the use of car and truck bombs by terrorist organizations has led NRC to evaluate the adequacy of licensee security against such threats. As part of this evaluation, one of the factors is the effectiveness of terrain and vegetation in providing barriers against the vehicle entry. The effectiveness of natural features is presented in two contexts. First, certain natural features are presented. Second, the effectiveness of combinations of features is presented. In addition to the discussion of natural features, this report provides a discussion of methods to slow vehicles. Also included is an overview of man-made barrier systems, with particular attention to ditches. 17 refs., 49 figs

  19. Contextual Multi-armed Bandits under Feature Uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Seyoung [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nam, Jun Hyun [Korea Advanced Inst. Science and Technology (KAIST), Daejeon (Korea, Republic of); Mo, Sangwoo [Korea Advanced Inst. Science and Technology (KAIST), Daejeon (Korea, Republic of); Shin, Jinwoo [Korea Advanced Inst. Science and Technology (KAIST), Daejeon (Korea, Republic of)

    2017-03-03

    We study contextual multi-armed bandit problems under linear realizability on rewards and uncertainty (or noise) on features. For the case of identical noise on features across actions, we propose an algorithm, coined NLinRel, having O(T⁷/₈(log(dT)+K√d)) regret bound for T rounds, K actions, and d-dimensional feature vectors. Next, for the case of non-identical noise, we observe that popular linear hypotheses including NLinRel are impossible to achieve such sub-linear regret. Instead, under assumption of Gaussian feature vectors, we prove that a greedy algorithm has O(T²/₃√log d)regret bound with respect to the optimal linear hypothesis. Utilizing our theoretical understanding on the Gaussian case, we also design a practical variant of NLinRel, coined Universal-NLinRel, for arbitrary feature distributions. It first runs NLinRel for finding the ‘true’ coefficient vector using feature uncertainties and then adjust it to minimize its regret using the statistical feature information. We justify the performance of Universal-NLinRel on both synthetic and real-world datasets.

  20. Unsupervised feature learning for autonomous rock image classification

    Science.gov (United States)

    Shu, Lei; McIsaac, Kenneth; Osinski, Gordon R.; Francis, Raymond

    2017-09-01

    Autonomous rock image classification can enhance the capability of robots for geological detection and enlarge the scientific returns, both in investigation on Earth and planetary surface exploration on Mars. Since rock textural images are usually inhomogeneous and manually hand-crafting features is not always reliable, we propose an unsupervised feature learning method to autonomously learn the feature representation for rock images. In our tests, rock image classification using the learned features shows that the learned features can outperform manually selected features. Self-taught learning is also proposed to learn the feature representation from a large database of unlabelled rock images of mixed class. The learned features can then be used repeatedly for classification of any subclass. This takes advantage of the large dataset of unlabelled rock images and learns a general feature representation for many kinds of rocks. We show experimental results supporting the feasibility of self-taught learning on rock images.

  1. Naive Bayes-Guided Bat Algorithm for Feature Selection

    Directory of Open Access Journals (Sweden)

    Ahmed Majid Taha

    2013-01-01

    Full Text Available When the amount of data and information is said to double in every 20 months or so, feature selection has become highly important and beneficial. Further improvements in feature selection will positively affect a wide array of applications in fields such as pattern recognition, machine learning, or signal processing. Bio-inspired method called Bat Algorithm hybridized with a Naive Bayes classifier has been presented in this work. The performance of the proposed feature selection algorithm was investigated using twelve benchmark datasets from different domains and was compared to three other well-known feature selection algorithms. Discussion focused on four perspectives: number of features, classification accuracy, stability, and feature generalization. The results showed that BANB significantly outperformed other algorithms in selecting lower number of features, hence removing irrelevant, redundant, or noisy features while maintaining the classification accuracy. BANB is also proven to be more stable than other methods and is capable of producing more general feature subsets.

  2. Naive Bayes-Guided Bat Algorithm for Feature Selection

    Science.gov (United States)

    Taha, Ahmed Majid; Mustapha, Aida; Chen, Soong-Der

    2013-01-01

    When the amount of data and information is said to double in every 20 months or so, feature selection has become highly important and beneficial. Further improvements in feature selection will positively affect a wide array of applications in fields such as pattern recognition, machine learning, or signal processing. Bio-inspired method called Bat Algorithm hybridized with a Naive Bayes classifier has been presented in this work. The performance of the proposed feature selection algorithm was investigated using twelve benchmark datasets from different domains and was compared to three other well-known feature selection algorithms. Discussion focused on four perspectives: number of features, classification accuracy, stability, and feature generalization. The results showed that BANB significantly outperformed other algorithms in selecting lower number of features, hence removing irrelevant, redundant, or noisy features while maintaining the classification accuracy. BANB is also proven to be more stable than other methods and is capable of producing more general feature subsets. PMID:24396295

  3. Less common CT features of medulloblastoma

    International Nuclear Information System (INIS)

    Zee, C.S; Segall, H.D.; Miller, C.; Ahmad, J.; McComb, J.G.; Han, J.S.; Park, S.H.

    1982-01-01

    While many medulloblastomas have characteristic features on computed tomography (CT), a significant number have atypical features, including a cystic or necrotic component, calcification, hemorrhage, lack of contrast enhancement, and eccentric location, and/or direct supratentorial extension. Of 30 consecutive untreated cases reviewed by the authors, 14 (47%) had such findings. Failure to make the proper diagnosis will result in some cases if these features are not recognized as possible signs of medulloblastoma

  4. Improving scale invariant feature transform-based descriptors with shape-color alliance robust feature

    Science.gov (United States)

    Wang, Rui; Zhu, Zhengdan; Zhang, Liang

    2015-05-01

    Constructing appropriate descriptors for interest points in image matching is a critical aspect task in computer vision and pattern recognition. A method as an extension of the scale invariant feature transform (SIFT) descriptor called shape-color alliance robust feature (SCARF) descriptor is presented. To address the problem that SIFT is designed mainly for gray images and lack of global information for feature points, the proposed approach improves the SIFT descriptor by means of a concentric-rings model, as well as integrating the color invariant space and shape context with SIFT to construct the SCARF descriptor. The SCARF method developed is more robust than the conventional SIFT with respect to not only the color and photometrical variations but also the measuring similarity as a global variation between two shapes. A comparative evaluation of different descriptors is carried out showing that the SCARF approach provides better results than the other four state-of-the-art related methods.

  5. Discriminative semi-supervised feature selection via manifold regularization.

    Science.gov (United States)

    Xu, Zenglin; King, Irwin; Lyu, Michael Rung-Tsong; Jin, Rong

    2010-07-01

    Feature selection has attracted a huge amount of interest in both research and application communities of data mining. We consider the problem of semi-supervised feature selection, where we are given a small amount of labeled examples and a large amount of unlabeled examples. Since a small number of labeled samples are usually insufficient for identifying the relevant features, the critical problem arising from semi-supervised feature selection is how to take advantage of the information underneath the unlabeled data. To address this problem, we propose a novel discriminative semi-supervised feature selection method based on the idea of manifold regularization. The proposed approach selects features through maximizing the classification margin between different classes and simultaneously exploiting the geometry of the probability distribution that generates both labeled and unlabeled data. In comparison with previous semi-supervised feature selection algorithms, our proposed semi-supervised feature selection method is an embedded feature selection method and is able to find more discriminative features. We formulate the proposed feature selection method into a convex-concave optimization problem, where the saddle point corresponds to the optimal solution. To find the optimal solution, the level method, a fairly recent optimization method, is employed. We also present a theoretic proof of the convergence rate for the application of the level method to our problem. Empirical evaluation on several benchmark data sets demonstrates the effectiveness of the proposed semi-supervised feature selection method.

  6. Feature Evaluation for Building Facade Images - AN Empirical Study

    Science.gov (United States)

    Yang, M. Y.; Förstner, W.; Chai, D.

    2012-08-01

    The classification of building facade images is a challenging problem that receives a great deal of attention in the photogrammetry community. Image classification is critically dependent on the features. In this paper, we perform an empirical feature evaluation task for building facade images. Feature sets we choose are basic features, color features, histogram features, Peucker features, texture features, and SIFT features. We present an approach for region-wise labeling using an efficient randomized decision forest classifier and local features. We conduct our experiments with building facade image classification on the eTRIMS dataset, where our focus is the object classes building, car, door, pavement, road, sky, vegetation, and window.

  7. Schizophrenia classification using functional network features

    Science.gov (United States)

    Rish, Irina; Cecchi, Guillermo A.; Heuton, Kyle

    2012-03-01

    This paper focuses on discovering statistical biomarkers (features) that are predictive of schizophrenia, with a particular focus on topological properties of fMRI functional networks. We consider several network properties, such as node (voxel) strength, clustering coefficients, local efficiency, as well as just a subset of pairwise correlations. While all types of features demonstrate highly significant statistical differences in several brain areas, and close to 80% classification accuracy, the most remarkable results of 93% accuracy are achieved by using a small subset of only a dozen of most-informative (lowest p-value) correlation features. Our results suggest that voxel-level correlations and functional network features derived from them are highly informative about schizophrenia and can be used as statistical biomarkers for the disease.

  8. Rigid rod spaced fullerene as building block for nanoclusters

    Indian Academy of Sciences (India)

    By using phenylacetylene based rigid-rod linkers (PhA), we have successfully synthesized two fullerene derivatives, C60-PhA and C60-PhA-C60. The absorption spectral features of C60, as well as that of the phenylacetylene moiety are retained in the monomeric forms of these fullerene derivatives, ruling out the possibility ...

  9. Classification Using Markov Blanket for Feature Selection

    DEFF Research Database (Denmark)

    Zeng, Yifeng; Luo, Jian

    2009-01-01

    Selecting relevant features is in demand when a large data set is of interest in a classification task. It produces a tractable number of features that are sufficient and possibly improve the classification performance. This paper studies a statistical method of Markov blanket induction algorithm...... for filtering features and then applies a classifier using the Markov blanket predictors. The Markov blanket contains a minimal subset of relevant features that yields optimal classification performance. We experimentally demonstrate the improved performance of several classifiers using a Markov blanket...... induction as a feature selection method. In addition, we point out an important assumption behind the Markov blanket induction algorithm and show its effect on the classification performance....

  10. Hierarchical feature selection for erythema severity estimation

    Science.gov (United States)

    Wang, Li; Shi, Chenbo; Shu, Chang

    2014-10-01

    At present PASI system of scoring is used for evaluating erythema severity, which can help doctors to diagnose psoriasis [1-3]. The system relies on the subjective judge of doctors, where the accuracy and stability cannot be guaranteed [4]. This paper proposes a stable and precise algorithm for erythema severity estimation. Our contributions are twofold. On one hand, in order to extract the multi-scale redness of erythema, we design the hierarchical feature. Different from traditional methods, we not only utilize the color statistical features, but also divide the detect window into small window and extract hierarchical features. Further, a feature re-ranking step is introduced, which can guarantee that extracted features are irrelevant to each other. On the other hand, an adaptive boosting classifier is applied for further feature selection. During the step of training, the classifier will seek out the most valuable feature for evaluating erythema severity, due to its strong learning ability. Experimental results demonstrate the high precision and robustness of our algorithm. The accuracy is 80.1% on the dataset which comprise 116 patients' images with various kinds of erythema. Now our system has been applied for erythema medical efficacy evaluation in Union Hosp, China.

  11. Discriminating Induced-Microearthquakes Using New Seismic Features

    Science.gov (United States)

    Mousavi, S. M.; Horton, S.

    2016-12-01

    We studied characteristics of induced-microearthquakes on the basis of the waveforms recorded on a limited number of surface receivers using machine-learning techniques. Forty features in the time, frequency, and time-frequency domains were measured on each waveform, and several techniques such as correlation-based feature selection, Artificial Neural Networks (ANNs), Logistic Regression (LR) and X-mean were used as research tools to explore the relationship between these seismic features and source parameters. The results show that spectral features have the highest correlation to source depth. Two new measurements developed as seismic features for this study, spectral centroids and 2D cross-correlations in the time-frequency domain, performed better than the common seismic measurements. These features can be used by machine learning techniques for efficient automatic classification of low energy signals recorded at one or more seismic stations. We applied the technique to 440 microearthquakes-1.7Reference: Mousavi, S.M., S.P. Horton, C. A. Langston, B. Samei, (2016) Seismic features and automatic discrimination of deep and shallow induced-microearthquakes using neural network and logistic regression, Geophys. J. Int. doi: 10.1093/gji/ggw258.

  12. Effective Feature Preprocessing for Time Series Forecasting

    DEFF Research Database (Denmark)

    Zhao, Junhua; Dong, Zhaoyang; Xu, Zhao

    2006-01-01

    Time series forecasting is an important area in data mining research. Feature preprocessing techniques have significant influence on forecasting accuracy, therefore are essential in a forecasting model. Although several feature preprocessing techniques have been applied in time series forecasting...... performance in time series forecasting. It is demonstrated in our experiment that, effective feature preprocessing can significantly enhance forecasting accuracy. This research can be a useful guidance for researchers on effectively selecting feature preprocessing techniques and integrating them with time...... series forecasting models....

  13. Feature-specific encoding flexibility in visual working memory.

    Directory of Open Access Journals (Sweden)

    Aki Kondo

    Full Text Available The current study examined selective encoding in visual working memory by systematically investigating interference from task-irrelevant features. The stimuli were objects defined by three features (color, shape, and location, and during a delay period, any of the features could switch between two objects. Additionally, single- and whole-probe trials were randomized within experimental blocks to investigate effects of memory retrieval. A series of relevant-feature switch detection tasks, where one feature was task-irrelevant, showed that interference from the task-irrelevant feature was only observed in the color-shape task, suggesting that color and shape information could be successfully filtered out, but location information could not, even when location was a task-irrelevant feature. Therefore, although location information is added to object representations independent of task demands in a relatively automatic manner, other features (e.g., color, shape can be flexibly added to object representations.

  14. Feature-specific encoding flexibility in visual working memory.

    Science.gov (United States)

    Kondo, Aki; Saiki, Jun

    2012-01-01

    The current study examined selective encoding in visual working memory by systematically investigating interference from task-irrelevant features. The stimuli were objects defined by three features (color, shape, and location), and during a delay period, any of the features could switch between two objects. Additionally, single- and whole-probe trials were randomized within experimental blocks to investigate effects of memory retrieval. A series of relevant-feature switch detection tasks, where one feature was task-irrelevant, showed that interference from the task-irrelevant feature was only observed in the color-shape task, suggesting that color and shape information could be successfully filtered out, but location information could not, even when location was a task-irrelevant feature. Therefore, although location information is added to object representations independent of task demands in a relatively automatic manner, other features (e.g., color, shape) can be flexibly added to object representations.

  15. EEG feature selection method based on decision tree.

    Science.gov (United States)

    Duan, Lijuan; Ge, Hui; Ma, Wei; Miao, Jun

    2015-01-01

    This paper aims to solve automated feature selection problem in brain computer interface (BCI). In order to automate feature selection process, we proposed a novel EEG feature selection method based on decision tree (DT). During the electroencephalogram (EEG) signal processing, a feature extraction method based on principle component analysis (PCA) was used, and the selection process based on decision tree was performed by searching the feature space and automatically selecting optimal features. Considering that EEG signals are a series of non-linear signals, a generalized linear classifier named support vector machine (SVM) was chosen. In order to test the validity of the proposed method, we applied the EEG feature selection method based on decision tree to BCI Competition II datasets Ia, and the experiment showed encouraging results.

  16. Text feature extraction based on deep learning: a review.

    Science.gov (United States)

    Liang, Hong; Sun, Xiao; Sun, Yunlei; Gao, Yuan

    2017-01-01

    Selection of text feature item is a basic and important matter for text mining and information retrieval. Traditional methods of feature extraction require handcrafted features. To hand-design, an effective feature is a lengthy process, but aiming at new applications, deep learning enables to acquire new effective feature representation from training data. As a new feature extraction method, deep learning has made achievements in text mining. The major difference between deep learning and conventional methods is that deep learning automatically learns features from big data, instead of adopting handcrafted features, which mainly depends on priori knowledge of designers and is highly impossible to take the advantage of big data. Deep learning can automatically learn feature representation from big data, including millions of parameters. This thesis outlines the common methods used in text feature extraction first, and then expands frequently used deep learning methods in text feature extraction and its applications, and forecasts the application of deep learning in feature extraction.

  17. The Non-motor Features of Essential Tremor: A Primary Disease Feature or Just a Secondary Phenomenon?

    Directory of Open Access Journals (Sweden)

    Ketan Jhunjhunwala

    2014-08-01

    Full Text Available Essential tremor (ET is a pathologically heterogeneous neurodegenerative disorder with both motor and increasingly recognized non-motor features. It is debated whether the non-motor manifestations in ET result from widespread neurodegeneration or are merely secondary to impaired motor functions and decreased quality of life due to tremor. It is important to review these features to determine how to best treat the non-motor symptoms of patients and to understand the basic pathophysiology of the disease and develop appropriate pharmacotherapies. In this review, retrospective and prospective clinical studies were critically analyzed to identify possible correlations between the severities of non-motor features and tremor. We speculated that if such a correlation existed, the non-motor features were likely to be secondary to tremor. According to the current literature, the deficits in executive function, attention, concentration, and memory often observed in ET are likely to be a primary manifestation of the disease. It has also been documented that patients with ET often exhibit characteristic personality traits. However, it remains to be determined whether the other non-motor features often seen in ET, such as anxiety, depression, and sleep disturbances are primary or secondary to motor manifestations of ET and subsequent poor quality of life. Finally, there is evidence that patients with ET can also have impaired color vision, disturbances of olfaction, and hearing impairments, though there are few studies in these areas. Further investigations of large cohorts of patients with ET are required to understand the prevalence, nature, and true significance of the non-motor features in ET.

  18. CT features of renal epithelioid angiomyolipomas

    International Nuclear Information System (INIS)

    Hu Xiaoyun; Fang Xiangming; Hu Chunhong; Chen Hongwei; Cui Lei; Bao Jian; Yao Xuanjun

    2010-01-01

    Objective: To explore the CT and pathological features of renal epithelioid angiomyolipoma (EAML). Methods: Clinical data and CT images from ten cases with EAML proved by surgery and pathology were retrospectively analyzed. All cases were performed with plain and contrast enhanced CT scans. Results: CT features: higher pre-contrasted density than kidney, bulging from kidney, absent of fat, markedly heterogeneous enhancement (quick wash-in and slow wash-out), big size without lobular sign, complete capsule with clear margin and mild necrostic area. Pathological features: diffuse sheets of epithelioid cells were found under microscopy with immunohistochemistrical findings including positivity for HMB-45 and negativity for EMA. Conclusion: Some specific CT features, which is correlated well with the pathological findings, provide helpful information in the primary diagnosis of EAML. (authors)

  19. Feature Extraction in Radar Target Classification

    Directory of Open Access Journals (Sweden)

    Z. Kus

    1999-09-01

    Full Text Available This paper presents experimental results of extracting features in the Radar Target Classification process using the J frequency band pulse radar. The feature extraction is based on frequency analysis methods, the discrete-time Fourier Transform (DFT and Multiple Signal Characterisation (MUSIC, based on the detection of Doppler effect. The analysis has turned to the preference of DFT with implemented Hanning windowing function. We assumed to classify targets-vehicles into two classes, the wheeled vehicle and tracked vehicle. The results show that it is possible to classify them only while moving. The feature of the class results from a movement of moving parts of the vehicle. However, we have not found any feature to classify the wheeled and tracked vehicles while non-moving, although their engines are on.

  20. Considerations of the Effects of Naphthalene Moieties on the Design of Proton-Conductive Poly(arylene ether ketone) Membranes for Direct Methanol Fuel Cells.

    Science.gov (United States)

    Wang, Baolong; Hong, Lihua; Li, Yunfeng; Zhao, Liang; Wei, Yuxue; Zhao, Chengji; Na, Hui

    2016-09-14

    Novel sulfonated poly(arylene ether ketones) (SDN-PAEK-x), consisting of dual naphthalene and flexible sulfoalkyl groups, were prepared via polycondensation, demethylation, and sulfobutylation grafting reaction. Among them, SDN-PAEK-1.94 membrane with the highest ion exchange capacity (IEC = 2.46 mequiv·g(-1)) exhibited the highest proton conductivity, which was 0.147 S· cm(-1) at 25 °C and 0.271 S·cm(-1) at 80 °C, respectively. The introduction of dual naphthalene moieties is expected to achieve much enhanced properties compared to those of sulfonated poly(arylene ether ketones) (SNPAEK-x), consisting of single naphthalene and flexible sulfoalkyl groups. Compared with SNPAEK-1.60 with a similar IEC, SDN-PAEK-1.74 membrane showed higher proton conductivity, higher IEC normalized conductivity, and higher effective proton mobility, although it had lower analytical acid concentration. The SDN-PAEK-x membranes with IECs higher than 1.96 mequiv·g(-1) also exhibited higher proton conductivity than that of recast Nafion membrane. Furthermore, SDN-PAEK-1.94 displayed a better single cell performance with a maximum power density of 60 mW·cm(-2) at 80 °C. Considering its high proton conductivity, excellent single cell performance, good mechanical stabilities, low membrane swelling, and methanol permeability, SDN-PAEK-x membranes are promising candidates as alternative polymer electrolyte membranes to Nafion for direct methanol fuel cell applications.

  1. Review of research in feature based design

    NARCIS (Netherlands)

    Salomons, O.W.; van Houten, Frederikus J.A.M.; Kals, H.J.J.

    1993-01-01

    Research in feature-based design is reviewed. Feature-based design is regarded as a key factor towards CAD/CAPP integration from a process planning point of view. From a design point of view, feature-based design offers possibilities for supporting the design process better than current CAD systems

  2. Genetic search feature selection for affective modeling

    DEFF Research Database (Denmark)

    Martínez, Héctor P.; Yannakakis, Georgios N.

    2010-01-01

    Automatic feature selection is a critical step towards the generation of successful computational models of affect. This paper presents a genetic search-based feature selection method which is developed as a global-search algorithm for improving the accuracy of the affective models built....... The method is tested and compared against sequential forward feature selection and random search in a dataset derived from a game survey experiment which contains bimodal input features (physiological and gameplay) and expressed pairwise preferences of affect. Results suggest that the proposed method...

  3. Feature Scaling via Second-Order Cone Programming

    Directory of Open Access Journals (Sweden)

    Zhizheng Liang

    2016-01-01

    Full Text Available Feature scaling has attracted considerable attention during the past several decades because of its important role in feature selection. In this paper, a novel algorithm for learning scaling factors of features is proposed. It first assigns a nonnegative scaling factor to each feature of data and then adopts a generalized performance measure to learn the optimal scaling factors. It is of interest to note that the proposed model can be transformed into a convex optimization problem: second-order cone programming (SOCP. Thus the scaling factors of features in our method are globally optimal in some sense. Several experiments on simulated data, UCI data sets, and the gene data set are conducted to demonstrate that the proposed method is more effective than previous methods.

  4. Shielding voices: The modulation of binding processes between voice features and response features by task representations.

    Science.gov (United States)

    Bogon, Johanna; Eisenbarth, Hedwig; Landgraf, Steffen; Dreisbach, Gesine

    2017-09-01

    Vocal events offer not only semantic-linguistic content but also information about the identity and the emotional-motivational state of the speaker. Furthermore, most vocal events have implications for our actions and therefore include action-related features. But the relevance and irrelevance of vocal features varies from task to task. The present study investigates binding processes for perceptual and action-related features of spoken words and their modulation by the task representation of the listener. Participants reacted with two response keys to eight different words spoken by a male or a female voice (Experiment 1) or spoken by an angry or neutral male voice (Experiment 2). There were two instruction conditions: half of participants learned eight stimulus-response mappings by rote (SR), and half of participants applied a binary task rule (TR). In both experiments, SR instructed participants showed clear evidence for binding processes between voice and response features indicated by an interaction between the irrelevant voice feature and the response. By contrast, as indicated by a three-way interaction with instruction, no such binding was found in the TR instructed group. These results are suggestive of binding and shielding as two adaptive mechanisms that ensure successful communication and action in a dynamic social environment.

  5. Integrated Phoneme Subspace Method for Speech Feature Extraction

    Directory of Open Access Journals (Sweden)

    Park Hyunsin

    2009-01-01

    Full Text Available Speech feature extraction has been a key focus in robust speech recognition research. In this work, we discuss data-driven linear feature transformations applied to feature vectors in the logarithmic mel-frequency filter bank domain. Transformations are based on principal component analysis (PCA, independent component analysis (ICA, and linear discriminant analysis (LDA. Furthermore, this paper introduces a new feature extraction technique that collects the correlation information among phoneme subspaces and reconstructs feature space for representing phonemic information efficiently. The proposed speech feature vector is generated by projecting an observed vector onto an integrated phoneme subspace (IPS based on PCA or ICA. The performance of the new feature was evaluated for isolated word speech recognition. The proposed method provided higher recognition accuracy than conventional methods in clean and reverberant environments.

  6. Does Attention Serve to Integrate Features?

    Science.gov (United States)

    Navon, David; Treisman, Anne

    1990-01-01

    An article and two commentaries consider the attentional feature-integration theory proposed by A. Treisman and colleagues. Hypotheses about the encoding of conjunctions are reviewed. Whether or not data support perceptual feature-integration is argued. (SLD)

  7. Crystal structures of a manganese(I and a rhenium(I complex of a bipyridine ligand with a non-coordinating benzoic acid moiety

    Directory of Open Access Journals (Sweden)

    Sheri Lense

    2018-05-01

    Full Text Available The structures of two facially coordinated Group VII metal complexes are reported, namely: fac-bromido[2-(2,2′-bipyridin-6-ylbenzoic acid-κ2N,N′]tricarbonylmanganese(I tetrahydrofuran monosolvate, [MnBr(C17H12N2O2(CO3]·C4H8O, I, and fac-[2-(2,2′-bipyridin-6-ylbenzoic acid-κ2N,N′]tricarbonylchloridorhenium(I tetrahydrofuran monosolvate, [ReCl(C17H12N2O2(CO3]·C4H8O, II. In both complexes, the metal ion is coordinated by three carbonyl ligands, a halide ion, and a 2-(2,2′-bipyridin-6-ylbenzoic acid ligand, in a distorted octahedral geometry. In manganese complex I, the tetrahydrofuran (THF solvent molecule could not be refined due to disorder. The benzoic acid fragment is also disordered over two positions, such that the carboxylic acid group is either positioned near to the bromide ligand or to the axial carbonyl ligand. In the crystal of I, the complex molecules are linked by a pair of C—H...Br hydrogen bonds, forming inversion dimers that stack up the a-axis direction. In the rhenium complex II, there is hydrogen bonding between the benzoic acid moiety and a disordered co-crystallized THF molecule. In the crystal, the molecules are linked by C—H...Cl hydrogen bonds, forming layers parallel to (100 separated by layers of THF solvent molecules.

  8. 14 CFR 35.7 - Features and characteristics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Features and characteristics. 35.7 Section... AIRWORTHINESS STANDARDS: PROPELLERS General § 35.7 Features and characteristics. (a) The propeller may not have features or characteristics, revealed by any test or analysis or known to the applicant, that make it...

  9. Finger vein recognition based on the hyperinformation feature

    Science.gov (United States)

    Xi, Xiaoming; Yang, Gongping; Yin, Yilong; Yang, Lu

    2014-01-01

    The finger vein is a promising biometric pattern for personal identification due to its advantages over other existing biometrics. In finger vein recognition, feature extraction is a critical step, and many feature extraction methods have been proposed to extract the gray, texture, or shape of the finger vein. We treat them as low-level features and present a high-level feature extraction framework. Under this framework, base attribute is first defined to represent the characteristics of a certain subcategory of a subject. Then, for an image, the correlation coefficient is used for constructing the high-level feature, which reflects the correlation between this image and all base attributes. Since the high-level feature can reveal characteristics of more subcategories and contain more discriminative information, we call it hyperinformation feature (HIF). Compared with low-level features, which only represent the characteristics of one subcategory, HIF is more powerful and robust. In order to demonstrate the potential of the proposed framework, we provide a case study to extract HIF. We conduct comprehensive experiments to show the generality of the proposed framework and the efficiency of HIF on our databases, respectively. Experimental results show that HIF significantly outperforms the low-level features.

  10. Increased Water Solubility of the Curcumin Derivatives via Substitution with an Acetoxy Group at the Central Methylene Moiety

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Kyoung; Mok, Hyejung; Chong, Youhoon [Konkuk Univ., Seoul (Korea, Republic of)

    2012-09-15

    Curcumin (diferuloyl methane), a natural yellow pigment in the roots of turmeric, has been considered as one of the most promising chemopreventive agents against a variety of human cancers. Curcumin is known to exhibit its antiproliferative effect against various cancer cells through cell cycle arrest and induction of apoptosis. Although not as potent as many other cytotoxic agents, curcumin has been demonstrated to be safe in humans at relatively high doses (10 grams/day), making it an attractive target for chemotherapeutic drug discovery efforts. Two compounds with meta-methoxy substituents (2 and 3) maintained comparable antiproliferative activity with curcumin (1). In contrast, the acetoxy-curcuminoids (8-14) showed moderate to potent activity against all three cancer cell lines tested (Table 1). In particular, the colon cancer cell (HCT116) was most susceptible to the acetoxy-curcuminoids (8-12, Table 1) to show 2-2.5 times increase in EC{sub 50} values compared with that of curcumin (1, Table 1). In this series, like the simple curcuminoids (2-7), the aromatic meta-methoxy substituent turned out to be critical for the antiproliferative effect, and the corresponding acetoxy-curcuminoids 10 and 11 showed the most potent activity against HCT116 with EC{sub 50} values of 18.5 μM and 16.9 μM, respectively. Also noteworthy is the broad spectrum antiproliferative effect of the acetoxy-curcuminoid 11 with a free catechol moiety, which exhibited almost similar antiproliferative activity against all three cancer cell lines tested. Taken together, through evaluation of solubility as well as antiproliferative effect of the acetoxy-curcuminoids, we figured out that the acetoxy group substituted at the central methylene unit which served to enhance the solubility of the corresponding curcuminoids also played a key role in potentiating their antiproliferative effect. Thus, upon combination of the methylenyl acetoxy group and the aromatic meta-methoxy group on the curcumin

  11. Increased Water Solubility of the Curcumin Derivatives via Substitution with an Acetoxy Group at the Central Methylene Moiety

    International Nuclear Information System (INIS)

    Kim, Mi Kyoung; Mok, Hyejung; Chong, Youhoon

    2012-01-01

    Curcumin (diferuloyl methane), a natural yellow pigment in the roots of turmeric, has been considered as one of the most promising chemopreventive agents against a variety of human cancers. Curcumin is known to exhibit its antiproliferative effect against various cancer cells through cell cycle arrest and induction of apoptosis. Although not as potent as many other cytotoxic agents, curcumin has been demonstrated to be safe in humans at relatively high doses (10 grams/day), making it an attractive target for chemotherapeutic drug discovery efforts. Two compounds with meta-methoxy substituents (2 and 3) maintained comparable antiproliferative activity with curcumin (1). In contrast, the acetoxy-curcuminoids (8-14) showed moderate to potent activity against all three cancer cell lines tested (Table 1). In particular, the colon cancer cell (HCT116) was most susceptible to the acetoxy-curcuminoids (8-12, Table 1) to show 2-2.5 times increase in EC 50 values compared with that of curcumin (1, Table 1). In this series, like the simple curcuminoids (2-7), the aromatic meta-methoxy substituent turned out to be critical for the antiproliferative effect, and the corresponding acetoxy-curcuminoids 10 and 11 showed the most potent activity against HCT116 with EC 50 values of 18.5 μM and 16.9 μM, respectively. Also noteworthy is the broad spectrum antiproliferative effect of the acetoxy-curcuminoid 11 with a free catechol moiety, which exhibited almost similar antiproliferative activity against all three cancer cell lines tested. Taken together, through evaluation of solubility as well as antiproliferative effect of the acetoxy-curcuminoids, we figured out that the acetoxy group substituted at the central methylene unit which served to enhance the solubility of the corresponding curcuminoids also played a key role in potentiating their antiproliferative effect. Thus, upon combination of the methylenyl acetoxy group and the aromatic meta-methoxy group on the curcumin framework

  12. Multi-scale salient feature extraction on mesh models

    KAUST Repository

    Yang, Yongliang; Shen, ChaoHui

    2012-01-01

    We present a new method of extracting multi-scale salient features on meshes. It is based on robust estimation of curvature on multiple scales. The coincidence between salient feature and the scale of interest can be established straightforwardly, where detailed feature appears on small scale and feature with more global shape information shows up on large scale. We demonstrate this multi-scale description of features accords with human perception and can be further used for several applications as feature classification and viewpoint selection. Experiments exhibit that our method as a multi-scale analysis tool is very helpful for studying 3D shapes. © 2012 Springer-Verlag.

  13. Passive Safety Features for Small Modular Reactors

    International Nuclear Information System (INIS)

    Ingersoll, Daniel T.

    2010-01-01

    The rapid growth in the size and complexity of commercial nuclear power plants in the 1970s spawned an interest in smaller, simpler designs that are inherently or intrinsically safe through the use of passive design features. Several designs were developed, but none were ever built, although some of their passive safety features were incorporated into large commercial plant designs that are being planned or built today. In recent years, several reactor vendors are actively redeveloping small modular reactor (SMR) designs with even greater use of passive features. Several designs incorporate the ultimate in passive safety they completely eliminate specific accident initiators from the design. Other design features help to reduce the likelihood of an accident or help to mitigate the accidents consequences, should one occur. While some passive safety features are common to most SMR designs, irrespective of the coolant technology, other features are specific to water, gas, or liquid-metal cooled SMR designs. The extensive use of passive safety features in SMRs promise to make these plants highly robust, protecting both the general public and the owner/investor. Once demonstrated, these plants should allow nuclear power to be used confidently for a broader range of customers and applications than will be possible with large plants alone.

  14. Effective traffic features selection algorithm for cyber-attacks samples

    Science.gov (United States)

    Li, Yihong; Liu, Fangzheng; Du, Zhenyu

    2018-05-01

    By studying the defense scheme of Network attacks, this paper propose an effective traffic features selection algorithm based on k-means++ clustering to deal with the problem of high dimensionality of traffic features which extracted from cyber-attacks samples. Firstly, this algorithm divide the original feature set into attack traffic feature set and background traffic feature set by the clustering. Then, we calculates the variation of clustering performance after removing a certain feature. Finally, evaluating the degree of distinctiveness of the feature vector according to the result. Among them, the effective feature vector is whose degree of distinctiveness exceeds the set threshold. The purpose of this paper is to select out the effective features from the extracted original feature set. In this way, it can reduce the dimensionality of the features so as to reduce the space-time overhead of subsequent detection. The experimental results show that the proposed algorithm is feasible and it has some advantages over other selection algorithms.

  15. Prominent feature extraction for review analysis: an empirical study

    Science.gov (United States)

    Agarwal, Basant; Mittal, Namita

    2016-05-01

    Sentiment analysis (SA) research has increased tremendously in recent times. SA aims to determine the sentiment orientation of a given text into positive or negative polarity. Motivation for SA research is the need for the industry to know the opinion of the users about their product from online portals, blogs, discussion boards and reviews and so on. Efficient features need to be extracted for machine-learning algorithm for better sentiment classification. In this paper, initially various features are extracted such as unigrams, bi-grams and dependency features from the text. In addition, new bi-tagged features are also extracted that conform to predefined part-of-speech patterns. Furthermore, various composite features are created using these features. Information gain (IG) and minimum redundancy maximum relevancy (mRMR) feature selection methods are used to eliminate the noisy and irrelevant features from the feature vector. Finally, machine-learning algorithms are used for classifying the review document into positive or negative class. Effects of different categories of features are investigated on four standard data-sets, namely, movie review and product (book, DVD and electronics) review data-sets. Experimental results show that composite features created from prominent features of unigram and bi-tagged features perform better than other features for sentiment classification. mRMR is a better feature selection method as compared with IG for sentiment classification. Boolean Multinomial Naïve Bayes) algorithm performs better than support vector machine classifier for SA in terms of accuracy and execution time.

  16. MCNP4A: Features and philosophy

    International Nuclear Information System (INIS)

    Hendricks, J.S.

    1993-01-01

    This paper describes MCNP, states its philosophy, introduces a number of new features becoming available with version MCNP4A, and answers a number of questions asked by participants in the workshop. MCNP is a general-purpose three-dimensional neutron, photon and electron transport code. Its philosophy is ''Quality, Value and New Features.'' Quality is exemplified by new software quality assurance practices and a program of benchmarking against experiments. Value includes a strong emphasis on documentation and code portability. New features are the third priority. MCNP4A is now available at Los Alamos. New features in MCNP4A include enhanced statistical analysis, distributed processor multitasking, new photon libraries, ENDF/B-VI capabilities, X-Windows graphics, dynamic memory allocation, expanded criticality output, periodic boundaries, plotting of particle tracks via SABRINA, and many other improvements. 23 refs

  17. Interplay of a multiplicity of security features

    Science.gov (United States)

    Moser, Jean-Frederic

    2000-04-01

    The great variety of existing security features can cause difficulty in choosing the adequate set for a particular security document. Considering the cost/benefit aspects with respect to the overall protection performance requested, a choice has to be made, for example, between either few features of high-security value or numerous many, less- resistant features. Another choice is the high versus low complexity of one particular features. A study aimed at providing a decision basis is a challenging matter because it involves human factors. Attention, perception, physiology of seeing and habits - to name some of the factors - are intangibles and are subject to evaluations involving normally a great number of experiments, if they are to be representative. The opportunity was given for a case study with the introduction of new Swiss banknotes between 1995 and 1998, because the new banknotes represent a novelty in the sense of the multiplicity and interplay of its optical security features. We have analyzed 652 articles which appeared in the press media concerning the new banknotes, seeking especially for peoples' reaction towards the security features.

  18. Feature Vector Construction Method for IRIS Recognition

    Science.gov (United States)

    Odinokikh, G.; Fartukov, A.; Korobkin, M.; Yoo, J.

    2017-05-01

    One of the basic stages of iris recognition pipeline is iris feature vector construction procedure. The procedure represents the extraction of iris texture information relevant to its subsequent comparison. Thorough investigation of feature vectors obtained from iris showed that not all the vector elements are equally relevant. There are two characteristics which determine the vector element utility: fragility and discriminability. Conventional iris feature extraction methods consider the concept of fragility as the feature vector instability without respect to the nature of such instability appearance. This work separates sources of the instability into natural and encodinginduced which helps deeply investigate each source of instability independently. According to the separation concept, a novel approach of iris feature vector construction is proposed. The approach consists of two steps: iris feature extraction using Gabor filtering with optimal parameters and quantization with separated preliminary optimized fragility thresholds. The proposed method has been tested on two different datasets of iris images captured under changing environmental conditions. The testing results show that the proposed method surpasses all the methods considered as a prior art by recognition accuracy on both datasets.

  19. Disruption of visual feature binding in working memory.

    Science.gov (United States)

    Ueno, Taiji; Allen, Richard J; Baddeley, Alan D; Hitch, Graham J; Saito, Satoru

    2011-01-01

    In a series of five experiments, we studied the effect of a visual suffix on the retention in short-term visual memory of both individual visual features and objects involving the binding of two features. Experiments 1A, 1B, and 2 involved suffixes consisting of features external to the to-be-remembered set and revealed a modest but equivalent disruption on individual and bound feature conditions. Experiments 3A and 3B involved suffixes comprising features that could potentially have formed part of the to-be-remembered set (but did not on that trial). Both experiments showed greater disruption of retention for objects comprising bound features than for their individual features. The results are interpreted as differentiating two components of suffix interference, one affecting memory for features and bindings equally, the other affecting memory for bindings. The general component is tentatively identified with the attentional cost of operating a filter to prevent the suffix from entering visual working memory, whereas the specific component is attributed to the particular fragility of bound representations when the filter fails.

  20. Feature-based Alignment of Volumetric Multi-modal Images

    Science.gov (United States)

    Toews, Matthew; Zöllei, Lilla; Wells, William M.

    2014-01-01

    This paper proposes a method for aligning image volumes acquired from different imaging modalities (e.g. MR, CT) based on 3D scale-invariant image features. A novel method for encoding invariant feature geometry and appearance is developed, based on the assumption of locally linear intensity relationships, providing a solution to poor repeatability of feature detection in different image modalities. The encoding method is incorporated into a probabilistic feature-based model for multi-modal image alignment. The model parameters are estimated via a group-wise alignment algorithm, that iteratively alternates between estimating a feature-based model from feature data, then realigning feature data to the model, converging to a stable alignment solution with few pre-processing or pre-alignment requirements. The resulting model can be used to align multi-modal image data with the benefits of invariant feature correspondence: globally optimal solutions, high efficiency and low memory usage. The method is tested on the difficult RIRE data set of CT, T1, T2, PD and MP-RAGE brain images of subjects exhibiting significant inter-subject variability due to pathology. PMID:24683955

  1. Feature-Oriented Programming with Object Algebras

    NARCIS (Netherlands)

    B.C.d.S. Oliveira (Bruno); T. van der Storm (Tijs); A. Loh; W.R. Cook

    2013-01-01

    htmlabstractObject algebras are a new programming technique that enables a simple solution to basic extensibility and modularity issues in programming languages. While object algebras excel at defining modular features, the composition mechanisms for object algebras (and features) are still

  2. Biometric feature extraction using local fractal auto-correlation

    International Nuclear Information System (INIS)

    Chen Xi; Zhang Jia-Shu

    2014-01-01

    Image texture feature extraction is a classical means for biometric recognition. To extract effective texture feature for matching, we utilize local fractal auto-correlation to construct an effective image texture descriptor. Three main steps are involved in the proposed scheme: (i) using two-dimensional Gabor filter to extract the texture features of biometric images; (ii) calculating the local fractal dimension of Gabor feature under different orientations and scales using fractal auto-correlation algorithm; and (iii) linking the local fractal dimension of Gabor feature under different orientations and scales into a big vector for matching. Experiments and analyses show our proposed scheme is an efficient biometric feature extraction approach. (condensed matter: structural, mechanical, and thermal properties)

  3. Image feature detectors and descriptors foundations and applications

    CERN Document Server

    Hassaballah, Mahmoud

    2016-01-01

    This book provides readers with a selection of high-quality chapters that cover both theoretical concepts and practical applications of image feature detectors and descriptors. It serves as reference for researchers and practitioners by featuring survey chapters and research contributions on image feature detectors and descriptors. Additionally, it emphasizes several keywords in both theoretical and practical aspects of image feature extraction. The keywords include acceleration of feature detection and extraction, hardware implantations, image segmentation, evolutionary algorithm, ordinal measures, as well as visual speech recognition. .

  4. Organization Features and School Performance

    OpenAIRE

    Atkins, Lois Major

    2005-01-01

    The purpose of this study was to determine the odds of school organization features predicting schools meeting district or state performance goals. The school organization features were organizational complexity, shared decision making, and leadership behavior. The dependent variable was school performance, operationally defined as a principalâ s yes response or no response to the question, â did your school meet district or state performance goals.â The independent variables representing...

  5. Designing attractive gamification features for collaborative storytelling websites.

    Science.gov (United States)

    Hsu, Shang Hwa; Chang, Jen-Wei; Lee, Chun-Chia

    2013-06-01

    Gamification design is considered as the predictor of collaborative storytelling websites' success. Although aforementioned studies have mentioned a broad range of factors that may influence gamification, they neither depicted the actual design features nor relative attractiveness among them. This study aims to identify attractive gamification features for collaborative storytelling websites. We first constructed a hierarchical system structure of gamification design of collaborative storytelling websites and conducted a focus group interview with eighteen frequent users to identify 35gamification features. After that, this study determined the relative attractiveness of these gamification features by administrating an online survey to 6333 collaborative storytelling websites users. The results indicated that the top 10 most attractive gamification features could account for more than 50% of attractiveness among these 35 gamification features. The feature of unpredictable time pressure is important to website users, yet not revealed in previous relevant studies. Implications of the findings were discussed.

  6. Discovering highly informative feature set over high dimensions

    KAUST Repository

    Zhang, Chongsheng; Masseglia, Florent; Zhang, Xiangliang

    2012-01-01

    For many textual collections, the number of features is often overly large. These features can be very redundant, it is therefore desirable to have a small, succinct, yet highly informative collection of features that describes the key characteristics of a dataset. Information theory is one such tool for us to obtain this feature collection. With this paper, we mainly contribute to the improvement of efficiency for the process of selecting the most informative feature set over high-dimensional unlabeled data. We propose a heuristic theory for informative feature set selection from high dimensional data. Moreover, we design data structures that enable us to compute the entropies of the candidate feature sets efficiently. We also develop a simple pruning strategy that eliminates the hopeless candidates at each forward selection step. We test our method through experiments on real-world data sets, showing that our proposal is very efficient. © 2012 IEEE.

  7. Discovering highly informative feature set over high dimensions

    KAUST Repository

    Zhang, Chongsheng

    2012-11-01

    For many textual collections, the number of features is often overly large. These features can be very redundant, it is therefore desirable to have a small, succinct, yet highly informative collection of features that describes the key characteristics of a dataset. Information theory is one such tool for us to obtain this feature collection. With this paper, we mainly contribute to the improvement of efficiency for the process of selecting the most informative feature set over high-dimensional unlabeled data. We propose a heuristic theory for informative feature set selection from high dimensional data. Moreover, we design data structures that enable us to compute the entropies of the candidate feature sets efficiently. We also develop a simple pruning strategy that eliminates the hopeless candidates at each forward selection step. We test our method through experiments on real-world data sets, showing that our proposal is very efficient. © 2012 IEEE.

  8. Feature Selection for Chemical Sensor Arrays Using Mutual Information

    Science.gov (United States)

    Wang, X. Rosalind; Lizier, Joseph T.; Nowotny, Thomas; Berna, Amalia Z.; Prokopenko, Mikhail; Trowell, Stephen C.

    2014-01-01

    We address the problem of feature selection for classifying a diverse set of chemicals using an array of metal oxide sensors. Our aim is to evaluate a filter approach to feature selection with reference to previous work, which used a wrapper approach on the same data set, and established best features and upper bounds on classification performance. We selected feature sets that exhibit the maximal mutual information with the identity of the chemicals. The selected features closely match those found to perform well in the previous study using a wrapper approach to conduct an exhaustive search of all permitted feature combinations. By comparing the classification performance of support vector machines (using features selected by mutual information) with the performance observed in the previous study, we found that while our approach does not always give the maximum possible classification performance, it always selects features that achieve classification performance approaching the optimum obtained by exhaustive search. We performed further classification using the selected feature set with some common classifiers and found that, for the selected features, Bayesian Networks gave the best performance. Finally, we compared the observed classification performances with the performance of classifiers using randomly selected features. We found that the selected features consistently outperformed randomly selected features for all tested classifiers. The mutual information filter approach is therefore a computationally efficient method for selecting near optimal features for chemical sensor arrays. PMID:24595058

  9. The radiographic features of familial expansile osteolysis

    International Nuclear Information System (INIS)

    Crone, M.D.; Wallace, R.G.H.

    1990-01-01

    The radiographic features of a unique autosomal dominant bone dysplasia are presented. The features are classified as generalised and/or focal. Generalised features are either altered trabecular pattern or modelling abnormalities. Focal features comprise lytic areas which progressively enlarge, producing expansion of the bone and eventual disintegration due to fibrous and finally fatty replacement of the normal medulla. Almost 90% of these lesions occur in the appendicular skeleton. Clinically, hearing loss is the earliest manifestation of the disease, presenting sometimes as early as 4 years of age. Apical and cervical resorption of teeth is extremely common, resulting in premature loss of teeth. Radiologically, the differential diagnosis refers to Paget's disease, polyostotic fibrous dysplasia, and osteofibrous dysplasia. The progressive destruction of the bone is similar to massive osteolysis (Gorham's disease). The radiographic features in combination with the histopathology render the condition unique. (orig.)

  10. Probabilistic Slow Features for Behavior Analysis

    NARCIS (Netherlands)

    Zafeiriou, Lazaros; Nicolaou, Mihalis A.; Zafeiriou, Stefanos; Nikitidis, Symeon; Pantic, Maja

    A recently introduced latent feature learning technique for time-varying dynamic phenomena analysis is the so-called slow feature analysis (SFA). SFA is a deterministic component analysis technique for multidimensional sequences that, by minimizing the variance of the first-order time derivative

  11. Learning slow features for behavior analysis

    NARCIS (Netherlands)

    Zafeiriou, Lazaros; Nicolaou, Mihalis A.; Zafeiriou, Stefanos; Nikitids, Symeon; Pantic, Maja

    2013-01-01

    A recently introduced latent feature learning technique for time varying dynamic phenomena analysis is the socalled Slow Feature Analysis (SFA). SFA is a deterministic component analysis technique for multi-dimensional sequences that by minimizing the variance of the first order time derivative

  12. Aging, selective attention, and feature integration.

    Science.gov (United States)

    Plude, D J; Doussard-Roosevelt, J A

    1989-03-01

    This study used feature-integration theory as a means of determining the point in processing at which selective attention deficits originate. The theory posits an initial stage of processing in which features are registered in parallel and then a serial process in which features are conjoined to form complex stimuli. Performance of young and older adults on feature versus conjunction search is compared. Analyses of reaction times and error rates suggest that elderly adults in addition to young adults, can capitalize on the early parallel processing stage of visual information processing, and that age decrements in visual search arise as a result of the later, serial stage of processing. Analyses of a third, unconfounded, conjunction search condition reveal qualitatively similar modes of conjunction search in young and older adults. The contribution of age-related data limitations is found to be secondary to the contribution of age decrements in selective attention.

  13. Behind every innovative solution lies an obscure feature

    Directory of Open Access Journals (Sweden)

    Lee Spector (Fellow ISGEC

    2012-06-01

    Full Text Available The Obscure Features Hypothesis (OFH for innovation states that a two-step process undergirds almost all innovative solutions: (1 notice an infrequently observed or new (i.e., obscure feature of the problem and (2 construct an interaction involving the obscure feature that produces the desired effects to solve the problem. The OFH leads to a systematic derivation of innovation-enhancing techniques by engaging in two tasks. First, we developed a 32-category system of the types of features possessable by a physical object or material. This Feature Type Taxonomy (FTT provides a panoramic view of the space of features and assists in searches for the obscure ones. Second, we are articulating the many cognitive reasons that obscure features are overlooked and are developing countering techniques for each known reason. We present the implications and techniques of the OFH, as well as indicate how software can assist innovators in the effective use of these innovation-enhancing techniques.

  14. Mammographic feature enhancement by multiscale analysis

    International Nuclear Information System (INIS)

    Laine, A.F.; Schuler, S.; Fan, J.; Huda, W.

    1994-01-01

    This paper introduces a novel approach for accomplishing mammographic feature analysis by overcomplete multiresolution representations. The authors show that efficient representations may be identified within a continuum of scale-space and used to enhance features of importance to mammography. Methods of contrast enhancement are described based on three overcomplete multiscale representations: (1) the dyadic wavelet transform (separable), (2) the var-phi-transform (nonseparable, nonorthogonal), and (3) the hexagonal wavelet transform (nonseparable). Multiscale edges identified within distinct levels of transform space provide local support for image enhancement. Mammograms are reconstructed from wavelet coefficients modified at one or more levels by local and global nonlinear operators. In each case, edges and gain parameters are identified adaptively by a measure of energy within each level of scale-space. The authors show quantitatively that transform coefficients, modified by adaptive nonlinear operators, can make more obvious unseen or barely seen features of mammography without requiring additional radiation. The results are compared with traditional image enhancement techniques by measuring the local contrast of known mammographic features. The authors demonstrate that features extracted from multiresolution representations can provide an adaptive mechanism for accomplishing local contrast enhancement. By improving the visualization of breast pathology, they can improve chances of early detection while requiring less time to evaluate mammograms for most patients

  15. Laboratory simulation of infrared astrophysical features

    International Nuclear Information System (INIS)

    Rose, L.A.

    1979-01-01

    Laboratory infrared emission and absorption spectra have been taken of terrestrial silicates, meteorites and lunar soils in the form of micrometer and sub-micrometer grains. The emission spectra were taken in a way that imitates telescopic observations. The purpose was to see which materials best simulate the 10 μm astrophysical feature. The emission spectra of dunite, fayalite and Allende give a good fit to the 10 μm broadband emission feature of comets Bennett and Kohoutek. A study of the effect of grain size on the presence of the 10 μm emission features of dunite shows that for particles larger than 37 μm no feature is seen. The emission spectrum of the Murray meteorite, a Type 2 carbonaceous chondrite, is quite similar to the intermediate resolution spectrum of comet Kohoutek in the 10 μm region. Hydrous silicates or amorphous magnesium silicates in combination with high-temperature condensates, such as olivine or anorthite, would yield spectra that match the intermediate resolution spectrum of comet Kohoutek in the 10 μm region. Glassy olivine and glassy anorthite in approximately equal proportions would also give a spectrum that is a good fit to the cometary 10 μm feature. (Auth.)

  16. Joint Feature Selection and Classification for Multilabel Learning.

    Science.gov (United States)

    Huang, Jun; Li, Guorong; Huang, Qingming; Wu, Xindong

    2018-03-01

    Multilabel learning deals with examples having multiple class labels simultaneously. It has been applied to a variety of applications, such as text categorization and image annotation. A large number of algorithms have been proposed for multilabel learning, most of which concentrate on multilabel classification problems and only a few of them are feature selection algorithms. Current multilabel classification models are mainly built on a single data representation composed of all the features which are shared by all the class labels. Since each class label might be decided by some specific features of its own, and the problems of classification and feature selection are often addressed independently, in this paper, we propose a novel method which can perform joint feature selection and classification for multilabel learning, named JFSC. Different from many existing methods, JFSC learns both shared features and label-specific features by considering pairwise label correlations, and builds the multilabel classifier on the learned low-dimensional data representations simultaneously. A comparative study with state-of-the-art approaches manifests a competitive performance of our proposed method both in classification and feature selection for multilabel learning.

  17. Dispersive solid-phase microextraction and capillary electrophoresis separation of food colorants in beverages using diamino moiety functionalized silica nanoparticles as both extractant and pseudostationary phase.

    Science.gov (United States)

    Liu, Feng-Jie; Liu, Chuan-Ting; Li, Wei; Tang, An-Na

    2015-01-01

    In this work, a new method for the determination of food colorants in beverage samples is developed, using diamino moiety functionalized silica nanoparticles (dASNPs) as both adsorbents in dispersive solid-phase microextraction (dSPME) and pseudostationary phases (PSPs) in capillary electrophoresis (CE) separation. dASNPs were firstly used as adsorbents for the preconcentration of four colorants by the dSPME process. After that, colorants were efficiently separated by CE using 30 mM phosphate buffer (pH 6.0) containing 2 mM β-CD and 0.9 mg/mL dASNPs as additives. All factors influencing dSPME and CE separations were optimized in detail. The investigated analytes showed good linearities with correlation coefficients (R(2)) higher than 0.9932. The limits of detection for the four food colorants were between 0.030 and 0.36 mg/L, which are lower than those reported previously. The established method was also used to analyze four colorants in beverage samples with recoveries ranging from 82.7% to 114.6%. To the best of our knowledge, this is the first time to use NPs both as extractants in dSPME and pseudostationary phases in CE for the analytical purpose. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Automatic feature-based grouping during multiple object tracking.

    Science.gov (United States)

    Erlikhman, Gennady; Keane, Brian P; Mettler, Everett; Horowitz, Todd S; Kellman, Philip J

    2013-12-01

    Contour interpolation automatically binds targets with distractors to impair multiple object tracking (Keane, Mettler, Tsoi, & Kellman, 2011). Is interpolation special in this regard or can other features produce the same effect? To address this question, we examined the influence of eight features on tracking: color, contrast polarity, orientation, size, shape, depth, interpolation, and a combination (shape, color, size). In each case, subjects tracked 4 of 8 objects that began as undifferentiated shapes, changed features as motion began (to enable grouping), and returned to their undifferentiated states before halting. We found that intertarget grouping improved performance for all feature types except orientation and interpolation (Experiment 1 and Experiment 2). Most importantly, target-distractor grouping impaired performance for color, size, shape, combination, and interpolation. The impairments were, at times, large (>15% decrement in accuracy) and occurred relative to a homogeneous condition in which all objects had the same features at each moment of a trial (Experiment 2), and relative to a "diversity" condition in which targets and distractors had different features at each moment (Experiment 3). We conclude that feature-based grouping occurs for a variety of features besides interpolation, even when irrelevant to task instructions and contrary to the task demands, suggesting that interpolation is not unique in promoting automatic grouping in tracking tasks. Our results also imply that various kinds of features are encoded automatically and in parallel during tracking.

  19. Superpixel-Based Feature for Aerial Image Scene Recognition

    Directory of Open Access Journals (Sweden)

    Hongguang Li

    2018-01-01

    Full Text Available Image scene recognition is a core technology for many aerial remote sensing applications. Different landforms are inputted as different scenes in aerial imaging, and all landform information is regarded as valuable for aerial image scene recognition. However, the conventional features of the Bag-of-Words model are designed using local points or other related information and thus are unable to fully describe landform areas. This limitation cannot be ignored when the aim is to ensure accurate aerial scene recognition. A novel superpixel-based feature is proposed in this study to characterize aerial image scenes. Then, based on the proposed feature, a scene recognition method of the Bag-of-Words model for aerial imaging is designed. The proposed superpixel-based feature that utilizes landform information establishes top-task superpixel extraction of landforms to bottom-task expression of feature vectors. This characterization technique comprises the following steps: simple linear iterative clustering based superpixel segmentation, adaptive filter bank construction, Lie group-based feature quantification, and visual saliency model-based feature weighting. Experiments of image scene recognition are carried out using real image data captured by an unmanned aerial vehicle (UAV. The recognition accuracy of the proposed superpixel-based feature is 95.1%, which is higher than those of scene recognition algorithms based on other local features.

  20. Spatiotemporal Features for Asynchronous Event-based Data

    Directory of Open Access Journals (Sweden)

    Xavier eLagorce

    2015-02-01

    Full Text Available Bio-inspired asynchronous event-based vision sensors are currently introducing a paradigm shift in visual information processing. These new sensors rely on a stimulus-driven principle of light acquisition similar to biological retinas. They are event-driven and fully asynchronous, thereby reducing redundancy and encoding exact times of input signal changes, leading to a very precise temporal resolution. Approaches for higher-level computer vision often rely on the realiable detection of features in visual frames, but similar definitions of features for the novel dynamic and event-based visual input representation of silicon retinas have so far been lacking. This article addresses the problem of learning and recognizing features for event-based vision sensors, which capture properties of truly spatiotemporal volumes of sparse visual event information. A novel computational architecture for learning and encoding spatiotemporal features is introduced based on a set of predictive recurrent reservoir networks, competing via winner-take-all selection. Features are learned in an unsupervised manner from real-world input recorded with event-based vision sensors. It is shown that the networks in the architecture learn distinct and task-specific dynamic visual features, and can predict their trajectories over time.

  1. Selective Audiovisual Semantic Integration Enabled by Feature-Selective Attention.

    Science.gov (United States)

    Li, Yuanqing; Long, Jinyi; Huang, Biao; Yu, Tianyou; Wu, Wei; Li, Peijun; Fang, Fang; Sun, Pei

    2016-01-13

    An audiovisual object may contain multiple semantic features, such as the gender and emotional features of the speaker. Feature-selective attention and audiovisual semantic integration are two brain functions involved in the recognition of audiovisual objects. Humans often selectively attend to one or several features while ignoring the other features of an audiovisual object. Meanwhile, the human brain integrates semantic information from the visual and auditory modalities. However, how these two brain functions correlate with each other remains to be elucidated. In this functional magnetic resonance imaging (fMRI) study, we explored the neural mechanism by which feature-selective attention modulates audiovisual semantic integration. During the fMRI experiment, the subjects were presented with visual-only, auditory-only, or audiovisual dynamical facial stimuli and performed several feature-selective attention tasks. Our results revealed that a distribution of areas, including heteromodal areas and brain areas encoding attended features, may be involved in audiovisual semantic integration. Through feature-selective attention, the human brain may selectively integrate audiovisual semantic information from attended features by enhancing functional connectivity and thus regulating information flows from heteromodal areas to brain areas encoding the attended features.

  2. Enzyme-inspired functional surfactant for aerobic oxidation of activated alcohols to aldehydes in water

    KAUST Repository

    Chen, Batian; Bukhriakov, Konstantin; Sougrat, Rachid; Rodionov, Valentin

    2015-01-01

    We describe an enzyme-inspired catalytic system based on a rationally designed multifunctional amphiphile. The resulting micelles feature metal-binding sites and stable free radical moieties as well as fluorous pockets that attract and preconcentrate molecular oxygen. In the presence of copper ions, the micelles effect chemoselective aerobic alcohol oxidation under ambient conditions in water, a transformation that is challenging to achieve nonenzymatically.

  3. Enzyme-inspired functional surfactant for aerobic oxidation of activated alcohols to aldehydes in water

    KAUST Repository

    Chen, Batian

    2015-02-06

    We describe an enzyme-inspired catalytic system based on a rationally designed multifunctional amphiphile. The resulting micelles feature metal-binding sites and stable free radical moieties as well as fluorous pockets that attract and preconcentrate molecular oxygen. In the presence of copper ions, the micelles effect chemoselective aerobic alcohol oxidation under ambient conditions in water, a transformation that is challenging to achieve nonenzymatically.

  4. Critical feature analysis of a radiotherapy machine

    International Nuclear Information System (INIS)

    Rae, Andrew; Jackson, Daniel; Ramanan, Prasad; Flanz, Jay; Leyman, Didier

    2005-01-01

    The software implementation of the emergency shutdown feature in a major radiotherapy system was analyzed, using a directed form of code review based on module dependences. Dependences between modules are labelled by particular assumptions; this allows one to trace through the code, and identify those fragments responsible for critical features. An 'assumption tree' is constructed in parallel, showing the assumptions which each module makes about others. The root of the assumption tree is the critical feature of interest, and its leaves represent assumptions which, if not valid, might cause the critical feature to fail. The analysis revealed some unexpected assumptions that motivated improvements to the code

  5. Analysing Feature Model Changes using FMDiff

    NARCIS (Netherlands)

    Dintzner, N.J.R.; Van Deursen, A.; Pinzger, M.

    2015-01-01

    Evolving a large scale, highly variable sys- tems is a challenging task. For such a system, evolution operations often require to update consistently both their implementation and its feature model. In this con- text, the evolution of the feature model closely follows the evolution of the system.

  6. Graphical matching rules for cardinality based service feature diagrams

    Directory of Open Access Journals (Sweden)

    Faiza Kanwal

    2017-03-01

    Full Text Available To provide efficient services to end-users, variability and commonality among the features of the product line is a challenge for industrialist and researchers. Feature modeling provides great services to deal with variability and commonality among the features of product line. Cardinality based service feature diagrams changed the basic framework of service feature diagrams by putting constraints to them, which make service specifications more flexible, but apart from their variation in selection third party services may have to be customizable. Although to control variability, cardinality based service feature diagrams provide high level visual notations. For specifying variability, the use of cardinality based service feature diagrams raises the problem of matching a required feature diagram against the set of provided diagrams.

  7. Robust emotion recognition using spectral and prosodic features

    CERN Document Server

    Rao, K Sreenivasa

    2013-01-01

    In this brief, the authors discuss recently explored spectral (sub-segmental and pitch synchronous) and prosodic (global and local features at word and syllable levels in different parts of the utterance) features for discerning emotions in a robust manner. The authors also delve into the complementary evidences obtained from excitation source, vocal tract system and prosodic features for the purpose of enhancing emotion recognition performance. Features based on speaking rate characteristics are explored with the help of multi-stage and hybrid models for further improving emotion recognition performance. Proposed spectral and prosodic features are evaluated on real life emotional speech corpus.

  8. Video Scene Parsing with Predictive Feature Learning

    OpenAIRE

    Jin, Xiaojie; Li, Xin; Xiao, Huaxin; Shen, Xiaohui; Lin, Zhe; Yang, Jimei; Chen, Yunpeng; Dong, Jian; Liu, Luoqi; Jie, Zequn; Feng, Jiashi; Yan, Shuicheng

    2016-01-01

    In this work, we address the challenging video scene parsing problem by developing effective representation learning methods given limited parsing annotations. In particular, we contribute two novel methods that constitute a unified parsing framework. (1) \\textbf{Predictive feature learning}} from nearly unlimited unlabeled video data. Different from existing methods learning features from single frame parsing, we learn spatiotemporal discriminative features by enforcing a parsing network to ...

  9. Characters Feature Extraction Based on Neat Oracle Bone Rubbings

    OpenAIRE

    Lei Guo

    2013-01-01

    In order to recognize characters on the neat oracle bone rubbings, a new mesh point feature extraction algorithm was put forward in this paper by researching and improving of the existing coarse mesh feature extraction algorithm and the point feature extraction algorithm. Some improvements of this algorithm were as followings: point feature was introduced into the coarse mesh feature, the absolute address was converted to relative address, and point features have been changed grid and positio...

  10. Speech recognition using articulatory and excitation source features

    CERN Document Server

    Rao, K Sreenivasa

    2017-01-01

    This book discusses the contribution of articulatory and excitation source information in discriminating sound units. The authors focus on excitation source component of speech -- and the dynamics of various articulators during speech production -- for enhancement of speech recognition (SR) performance. Speech recognition is analyzed for read, extempore, and conversation modes of speech. Five groups of articulatory features (AFs) are explored for speech recognition, in addition to conventional spectral features. Each chapter provides the motivation for exploring the specific feature for SR task, discusses the methods to extract those features, and finally suggests appropriate models to capture the sound unit specific knowledge from the proposed features. The authors close by discussing various combinations of spectral, articulatory and source features, and the desired models to enhance the performance of SR systems.

  11. MRI features of placenta accreta

    International Nuclear Information System (INIS)

    Cao Manrui; Du Mu; Huang Yi; Liu Bingguang; Zhang Fangjing; Guo Jimin; Zhu Zhijun

    2012-01-01

    Objective: To investigate the MRI features of placenta accreta. Methods: From Apr 2009 to Jun 2011, 15 patients with placenta accrete received MRI examination. In them, placenta accreta was diagnosed based on clinical manifestations or postoperative histopathology. The MR features of placenta accreta in them (study group) were retrospectively analyzed and compared with those in 15 pregnant women without placenta accreta (control group) with Fisher exact test. Results: In the 15 patients with placenta accreta,uterine bulging and (or) a focal outward contour bulge was detected in 14 patients; heterogeneous signal intensity in the placenta was detected in 15 patients; dark intraplacental bands on T 2 -weighted images was detected in 15 patients; and increased subplacental vascularity was detected in 11 patients on T 1 - weighted images. In the study group, 14 patients showed at least three of the above four features, and in all of them uterine bulging and (or) a focal outward contour bulge, heterogeneous signal intensity in the placenta and dark intraplacental bands on T 2 -weighted images were detected; one patient showed heterogeneous signal intensity in the placenta, dark intraplacental bands on T 2 -weighted images and increased subplacental vascularity. In the control group,none patient had three of the above features.Uterine bulging and (or) a focal outward contour bulge, heterogeneous signal intensity in the placenta, dark intraplacental bands on T 2 -weighted images and increased subplacental vascularity were detected in 3, 6, 3 and 4 patients (P=0.000, 0.001, 0.000 and 0.027), respectively. Conclusions: The main MRI features of placenta accreta are uterine bulging and (or) a focal outward contour bulge, heterogeneous signal intensity in the placenta and dark intraplacental bands on T 2 -weighted images Besides, increased subplacental vascularity also could provide useful information for the diagnosis of placenta accreta. (authors)

  12. A study on feature analysis for musical instrument classification.

    Science.gov (United States)

    Deng, Jeremiah D; Simmermacher, Christian; Cranefield, Stephen

    2008-04-01

    In tackling data mining and pattern recognition tasks, finding a compact but effective set of features has often been found to be a crucial step in the overall problem-solving process. In this paper, we present an empirical study on feature analysis for recognition of classical instrument, using machine learning techniques to select and evaluate features extracted from a number of different feature schemes. It is revealed that there is significant redundancy between and within feature schemes commonly used in practice. Our results suggest that further feature analysis research is necessary in order to optimize feature selection and achieve better results for the instrument recognition problem.

  13. Audio feature extraction using probability distribution function

    Science.gov (United States)

    Suhaib, A.; Wan, Khairunizam; Aziz, Azri A.; Hazry, D.; Razlan, Zuradzman M.; Shahriman A., B.

    2015-05-01

    Voice recognition has been one of the popular applications in robotic field. It is also known to be recently used for biometric and multimedia information retrieval system. This technology is attained from successive research on audio feature extraction analysis. Probability Distribution Function (PDF) is a statistical method which is usually used as one of the processes in complex feature extraction methods such as GMM and PCA. In this paper, a new method for audio feature extraction is proposed which is by using only PDF as a feature extraction method itself for speech analysis purpose. Certain pre-processing techniques are performed in prior to the proposed feature extraction method. Subsequently, the PDF result values for each frame of sampled voice signals obtained from certain numbers of individuals are plotted. From the experimental results obtained, it can be seen visually from the plotted data that each individuals' voice has comparable PDF values and shapes.

  14. Temporality of Features in Near-Death Experience Narratives

    Directory of Open Access Journals (Sweden)

    Charlotte Martial

    2017-06-01

    Full Text Available Background: After an occurrence of a Near-Death Experience (NDE, Near-Death Experiencers (NDErs usually report extremely rich and detailed narratives. Phenomenologically, a NDE can be described as a set of distinguishable features. Some authors have proposed regular patterns of NDEs, however, the actual temporality sequence of NDE core features remains a little explored area.Objectives: The aim of the present study was to investigate the frequency distribution of these features (globally and according to the position of features in narratives as well as the most frequently reported temporality sequences of features.Methods: We collected 154 French freely expressed written NDE narratives (i.e., Greyson NDE scale total score ≥ 7/32. A text analysis was conducted on all narratives in order to infer temporal ordering and frequency distribution of NDE features.Results: Our analyses highlighted the following most frequently reported sequence of consecutive NDE features: Out-of-Body Experience, Experiencing a tunnel, Seeing a bright light, Feeling of peace. Yet, this sequence was encountered in a very limited number of NDErs.Conclusion: These findings may suggest that NDEs temporality sequences can vary across NDErs. Exploring associations and relationships among features encountered during NDEs may complete the rigorous definition and scientific comprehension of the phenomenon.

  15. Biofunctionalized nanoparticles with pH-responsive and cell penetrating blocks for gene delivery

    International Nuclear Information System (INIS)

    Gaspar, V M; Marques, J G; Sousa, F; Queiroz, J A; Correia, I J; Louro, R O

    2013-01-01

    Bridging the gap between nanoparticulate delivery systems and translational gene therapy is a long sought after requirement in nanomedicine-based applications. However, recent developments regarding nanoparticle functionalization have brought forward the ability to synthesize materials with biofunctional moieties that mimic the evolved features of viral particles. Herein we report the versatile conjugation of both cell penetrating arginine and pH-responsive histidine moieties into the chitosan polymeric backbone, to improve the physicochemical characteristics of the native material. Amino acid coupling was confirmed by 2D TOCSY NMR and Fourier transform infrared spectroscopy. The synthesized chitosan–histidine–arginine (CH–H–R) polymer complexed plasmid DNA biopharmaceuticals, and spontaneously assembled into stable 105 nm nanoparticles with spherical morphology and positive surface charge. The functionalized delivery systems were efficiently internalized into the intracellular compartment, and exhibited remarkably higher transfection efficiency than unmodified chitosan without causing any cytotoxic effect. Additional findings regarding intracellular trafficking events reveal their preferential escape from degradative lysosomal pathways and nuclear localization. Overall, this assembly of nanocarriers with bioinspired moieties provides the foundations for the design of efficient and customizable materials for cancer gene therapy. (paper)

  16. Hydrogel-Embedded Model Photocatalytic System Investigated by Raman and IR Spectroscopy Assisted by Density Functional Theory Calculations and Two-Dimensional Correlation Analysis.

    Science.gov (United States)

    Geitner, Robert; Götz, Stefan; Stach, Robert; Siegmann, Michael; Krebs, Patrick; Zechel, Stefan; Schreyer, Kristin; Winter, Andreas; Hager, Martin D; Schubert, Ulrich S; Gräfe, Stefanie; Dietzek, Benjamin; Mizaikoff, Boris; Schmitt, Michael; Popp, Jürgen

    2018-03-15

    The presented study reports the synthesis and the vibrational spectroscopic characterization of different matrix-embedded model photocatalysts. The goal of the study is to investigate the interaction of a polymer matrix with photosensitizing dyes and metal complexes for potential future photocatalytic applications. The synthesis focuses on a new rhodamine B derivate and a Pt(II) terpyridine complex, which both contain a polymerizable methacrylate moiety and an acid labile acylhydrazone group. The methacrylate moieties are afterward utilized to synthesize functional model hydrogels mainly consisting of poly(ethylene glycol) methacrylate units. The pH-dependent and temperature-dependent behavior of the hydrogels is investigated by means of Raman and IR spectroscopy assisted by density functional theory calculations and two-dimensional correlation spectroscopy. The spectroscopic results reveal that the Pt(II) terpyridine complex can be released from the polymer matrix by cleaving the C═N bond in an acid environment. The same behavior could not be observed in the case of the rhodamine B dye although it features a comparable C═N bond. The temperature-dependent study shows that the water evaporation has a significant influence neither on the molecular structure of the hydrogel nor on the model photocatalytic moieties.

  17. Feature Optimization for Long-Range Visual Homing in Changing Environments

    Directory of Open Access Journals (Sweden)

    Qidan Zhu

    2014-02-01

    Full Text Available This paper introduces a feature optimization method for robot long-range feature-based visual homing in changing environments. To cope with the changing environmental appearance, the optimization procedure is introduced to distinguish the most relevant features for feature-based visual homing, including the spatial distribution, selection and updating. In the previous research on feature-based visual homing, less effort has been spent on the way to improve the feature distribution to get uniformly distributed features, which are closely related to homing performance. This paper presents a modified feature extraction algorithm to decrease the influence of anisotropic feature distribution. In addition, the feature selection and updating mechanisms, which have hardly drawn any attention in the domain of feature-based visual homing, are crucial in improving homing accuracy and in maintaining the representation of changing environments. To verify the feasibility of the proposal, several comprehensive evaluations are conducted. The results indicate that the feature optimization method can find optimal feature sets for feature-based visual homing, and adapt the appearance representation to the changing environments as well.

  18. Acoustic Features Influence Musical Choices Across Multiple Genres.

    Science.gov (United States)

    Barone, Michael D; Bansal, Jotthi; Woolhouse, Matthew H

    2017-01-01

    Based on a large behavioral dataset of music downloads, two analyses investigate whether the acoustic features of listeners' preferred musical genres influence their choice of tracks within non-preferred, secondary musical styles. Analysis 1 identifies feature distributions for pairs of genre-defined subgroups that are distinct. Using correlation analysis, these distributions are used to test the degree of similarity between subgroups' main genres and the other music within their download collections. Analysis 2 explores the issue of main-to-secondary genre influence through the production of 10 feature-influence matrices, one per acoustic feature, in which cell values indicate the percentage change in features for genres and subgroups compared to overall population averages. In total, 10 acoustic features and 10 genre-defined subgroups are explored within the two analyses. Results strongly indicate that the acoustic features of people's main genres influence the tracks they download within non-preferred, secondary musical styles. The nature of this influence and its possible actuating mechanisms are discussed with respect to research on musical preference, personality, and statistical learning.

  19. Imaging features of kaposiform lymphangiomatosis

    International Nuclear Information System (INIS)

    Goyal, Pradeep; Alomari, Ahmad I.; Shaikh, Raja; Chaudry, Gulraiz; Kozakewich, Harry P.; Perez-Atayde, Antonio R.; Trenor, Cameron C.; Fishman, Steven J.; Greene, Arin K.

    2016-01-01

    Kaposiform lymphangiomatosis is a rare, aggressive lymphatic disorder. The imaging and presenting features of kaposiform lymphangiomatosis can overlap with those of central conducting lymphatic anomaly and generalized lymphatic anomaly. To analyze the imaging findings of kaposiform lymphangiomatosis disorder and highlight features most suggestive of this diagnosis. We retrospectively identified and characterized 20 children and young adults with histopathological diagnosis of kaposiform lymphangiomatosis and radiologic imaging referred to the vascular anomalies center between 1995 and 2015. The median age at onset was 6.5 years (range 3 months to 27 years). The most common presenting features were respiratory compromise (dyspnea, cough, chest pain; 55.5%), swelling/mass (25%), bleeding (15%) and fracture (5%). The thoracic cavity was involved in all patients; all patients had mediastinal involvement followed by lung parenchymal disease (90%) and pleural (85%) and pericardial (50%) effusions. The most common extra-thoracic sites of disease were the retroperitoneum (80%), bone (60%), abdominal viscera (55%) and muscles (45%). There was characteristic enhancing and infiltrative soft-tissue thickening in the mediastinum and retroperitoneum extending along the lymphatic distribution. Kaposiform lymphangiomatosis has overlapping imaging features with central conducting lymphatic anomaly and generalized lymphatic anomaly. Presence of mediastinal or retroperitoneal enhancing and infiltrative soft-tissue disease along the lymphatic distribution, hemorrhagic effusions and moderate thrombocytopenia (50-100,000/μl) should favor diagnosis of kaposiform lymphangiomatosis. (orig.)

  20. Spectral features in the cosmic ray fluxes

    Science.gov (United States)

    Lipari, Paolo

    2018-01-01

    The cosmic ray energy distributions contain spectral features, that is narrow energy regions where the slope of the spectrum changes rapidly. The identification and study of these features is of great importance to understand the astrophysical mechanisms of acceleration and propagation that form the spectra. In first approximation a spectral feature is often described as a discontinuous change in slope, however very valuable information is also contained in its width, that is the length of the energy interval where the change in spectral index develops. In this work we discuss the best way to define and parameterize the width a spectral feature, and for illustration discuss some of the most prominent known structures.

  1. A Novel Real-Time Feature Matching Scheme

    Directory of Open Access Journals (Sweden)

    Ying Liu

    2014-02-01

    Full Text Available Affine Scale Invariant Feature Transform (ASIFT can obtain fully affine invariance, however, its time cost reaches about twice that in Scale Invariant Feature Transform (SIFT. We propose an improved ASIFT algorithm based on feature points in scale space for real-time application. In order to detect the affine invariant feature point, we establish a second-order difference of Gaussian (DOG pyramid and replace the extreme detection in the DOG pyramid by zero detection in the proposed second-order DOG pyramid, which decreases the complexity of the scheme. Experimental results show that the proposed method has a big progress in the real-time performance compared to the traditional one, while preserving the fully affine invariance and precision.

  2. Suicide inactivation of cytochrome P-450 by methoxsalen. Evidence for the covalent binding of a reactive intermediate to the protein moiety

    International Nuclear Information System (INIS)

    Labbe, G.; Descatoire, V.; Beaune, P.; Letteron, P.; Larrey, D.; Pessayre, D.

    1989-01-01

    Incubation of rat liver microsomes with [3H]methoxsalen and NADPH resulted in the covalent binding of a methoxsalen intermediate to proteins comigrating with cytochromes P-450 UT-A, PB-B/D, ISF-G and PCN-E. Binding was increased by pretreatments with phenobarbital, beta-naphthoflavone (beta NF) and dexamethasone. Such pretreatments also increased the loss of CO-binding capacity either after administration of methoxsalen, or after incubation of hepatic microsomes with methoxsalen and NADPH. Immunoprecipitation of the methoxsalen metabolite-protein adducts in phenobarbital-induced microsomes was moderate with anti-UT-A antibodies, but marked with anti-PB-B/D and anti-PCN-E antibodies. Immunoprecipitation was observed also with anti-ISF-G (anti-beta NF-B) antibodies in beta NF-induced microsomes. Methoxsalen (0.25 mM) inhibited markedly the benzphetamine demethylase activity of phenobarbital-induced microsomes and the erythromycin demethylase activity of dexamethasone-induced microsomes. Whereas methoxsalen itself did not produce any binding spectrum, in contrast either in vivo administration of methoxsalen or incubation in vitro with methoxsalen and NADPH resulted in a low-to-high spin conversion of cytochrome P-450 as suggested by the appearance of a spectrum analogous to a type I binding spectrum. This low-to-high spin conversion was apparently due to a methoxsalen intermediate (probably, covalently bound to the protein and preventing partial sixth ligation of the iron). We conclude that suicide inactivation of cytochrome P-450 by methoxsalen is related to the covalent binding of a methoxsalen intermediate to the protein moiety of several cytochrome P-450 isoenzymes (including UT-A, PB-B/D, PCN-E as well as ISF-G and/or beta NF-B)

  3. Single-labelled music genre classification using content-based features

    CSIR Research Space (South Africa)

    Ajoodha, R

    2015-11-01

    Full Text Available In this paper we use content-based features to perform automatic classification of music pieces into genres. We categorise these features into four groups: features extracted from the Fourier transform’s magnitude spectrum, features designed...

  4. SIP-FS: a novel feature selection for data representation

    Directory of Open Access Journals (Sweden)

    Yiyou Guo

    2018-02-01

    Full Text Available Abstract Multiple features are widely used to characterize real-world datasets. It is desirable to select leading features with stability and interpretability from a set of distinct features for a comprehensive data description. However, most of existing feature selection methods focus on the predictability (e.g., prediction accuracy of selected results yet neglect stability. To obtain compact data representation, a novel feature selection method is proposed to improve stability, and interpretability without sacrificing predictability (SIP-FS. Instead of mutual information, generalized correlation is adopted in minimal redundancy maximal relevance to measure the relation between different feature types. Several feature types (each contains a certain number of features can then be selected and evaluated quantitatively to determine what types contribute to a specific class, thereby enhancing the so-called interpretability of features. Moreover, stability is introduced in the criterion of SIP-FS to obtain consistent results of ranking. We conduct experiments on three publicly available datasets using one-versus-all strategy to select class-specific features. The experiments illustrate that SIP-FS achieves significant performance improvements in terms of stability and interpretability with desirable prediction accuracy and indicates advantages over several state-of-the-art approaches.

  5. Integration of heterogeneous features for remote sensing scene classification

    Science.gov (United States)

    Wang, Xin; Xiong, Xingnan; Ning, Chen; Shi, Aiye; Lv, Guofang

    2018-01-01

    Scene classification is one of the most important issues in remote sensing (RS) image processing. We find that features from different channels (shape, spectral, texture, etc.), levels (low-level and middle-level), or perspectives (local and global) could provide various properties for RS images, and then propose a heterogeneous feature framework to extract and integrate heterogeneous features with different types for RS scene classification. The proposed method is composed of three modules (1) heterogeneous features extraction, where three heterogeneous feature types, called DS-SURF-LLC, mean-Std-LLC, and MS-CLBP, are calculated, (2) heterogeneous features fusion, where the multiple kernel learning (MKL) is utilized to integrate the heterogeneous features, and (3) an MKL support vector machine classifier for RS scene classification. The proposed method is extensively evaluated on three challenging benchmark datasets (a 6-class dataset, a 12-class dataset, and a 21-class dataset), and the experimental results show that the proposed method leads to good classification performance. It produces good informative features to describe the RS image scenes. Moreover, the integration of heterogeneous features outperforms some state-of-the-art features on RS scene classification tasks.

  6. EOG feature relevance determination for microsleep detection

    Directory of Open Access Journals (Sweden)

    Golz Martin

    2017-09-01

    Full Text Available Automatic relevance determination (ARD was applied to two-channel EOG recordings for microsleep event (MSE recognition. 10 s immediately before MSE and also before counterexamples of fatigued, but attentive driving were analysed. Two type of signal features were extracted: the maximum cross correlation (MaxCC and logarithmic power spectral densities (PSD averaged in spectral bands of 0.5 Hz width ranging between 0 and 8 Hz. Generalised learn-ing vector quantisation (GRLVQ was used as ARD method to show the potential of feature reduction. This is compared to support-vector machines (SVM, in which the feature reduction plays a much smaller role. Cross validation yielded mean normalised relevancies of PSD features in the range of 1.6 – 4.9 % and 1.9 – 10.4 % for horizontal and vertical EOG, respectively. MaxCC relevancies were 0.002 – 0.006 % and 0.002 – 0.06 %, respectively. This shows that PSD features of vertical EOG are indispensable, whereas MaxCC can be neglected. Mean classification accuracies were estimated at 86.6±b 1.3 % and 92.3±b 0.2 % for GRLVQ and SVM, respectively. GRLVQ permits objective feature reduction by inclusion of all processing stages, but is not as accurate as SVM.

  7. EOG feature relevance determination for microsleep detection

    Directory of Open Access Journals (Sweden)

    Golz Martin

    2017-09-01

    Full Text Available Automatic relevance determination (ARD was applied to two-channel EOG recordings for microsleep event (MSE recognition. 10 s immediately before MSE and also before counterexamples of fatigued, but attentive driving were analysed. Two type of signal features were extracted: the maximum cross correlation (MaxCC and logarithmic power spectral densities (PSD averaged in spectral bands of 0.5 Hz width ranging between 0 and 8 Hz. Generalised learn-ing vector quantisation (GRLVQ was used as ARD method to show the potential of feature reduction. This is compared to support-vector machines (SVM, in which the feature reduction plays a much smaller role. Cross validation yielded mean normalised relevancies of PSD features in the range of 1.6 - 4.9 % and 1.9 - 10.4 % for horizontal and vertical EOG, respectively. MaxCC relevancies were 0.002 - 0.006 % and 0.002 - 0.06 %, respectively. This shows that PSD features of vertical EOG are indispensable, whereas MaxCC can be neglected. Mean classification accuracies were estimated at 86.6±b 1.3 % and 92.3±b 0.2 % for GRLVQ and SVM, respec-tively. GRLVQ permits objective feature reduction by inclu-sion of all processing stages, but is not as accurate as SVM.

  8. Tunable features of magnetoelectric transformers.

    Science.gov (United States)

    Dong, Shuxiang; Zhai, Junyi; Priya, Shashank; Li, Jie-Fang; Viehland, Dwight

    2009-06-01

    We have found that magnetostrictive FeBSiC alloy ribbons laminated with piezoelectric Pb(Zr,Ti)O(3) fiber can act as a tunable transformer when driven under resonant conditions. These composites were also found to exhibit the strongest resonant magnetoelectric voltage coefficient of 750 V/cm-Oe. The tunable features were achieved by applying small dc magnetic biases of -5 transformer features can be attributed to large changes in the piezomagnetic coefficient and permeability of the magnetostrictive phase under H(dc).

  9. Enhanced feature integration in musicians

    DEFF Research Database (Denmark)

    Hansen, Niels Christian; Højlund, Andreas; Møller, Cecilie

    the classical oddball control paradigm which used identical sounds. This novel finding supports the dependent processing hypothesis suggesting that musicians recruit overlapping neural resources facilitating more holistic representations of domain-relevant stimuli. These specialised refinements in predictive......Distinguishing and integrating features of sensory input is essential to human survival and no less paramount in music perception and cognition. Yet, little is known about training-induced plasticity of neural mechanisms for auditory feature integration. This study aimed to contrast the two...

  10. Solving jigsaw puzzles using image features

    DEFF Research Database (Denmark)

    Nielsen, Ture R.; Drewsen, Peter; Hansen, Klaus

    2008-01-01

    In this article, we describe a method for automatic solving of the jigsaw puzzle problem based on using image features instead of the shape of the pieces. The image features are used for obtaining an accurate measure for edge similarity to be used in a new edge matching algorithm. The algorithm i...

  11. FEATURE EVALUATION FOR BUILDING FACADE IMAGES – AN EMPIRICAL STUDY

    Directory of Open Access Journals (Sweden)

    M. Y. Yang

    2012-08-01

    Full Text Available The classification of building facade images is a challenging problem that receives a great deal of attention in the photogrammetry community. Image classification is critically dependent on the features. In this paper, we perform an empirical feature evaluation task for building facade images. Feature sets we choose are basic features, color features, histogram features, Peucker features, texture features, and SIFT features. We present an approach for region-wise labeling using an efficient randomized decision forest classifier and local features. We conduct our experiments with building facade image classification on the eTRIMS dataset, where our focus is the object classes building, car, door, pavement, road, sky, vegetation, and window.

  12. Learning Transferable Features with Deep Adaptation Networks

    OpenAIRE

    Long, Mingsheng; Cao, Yue; Wang, Jianmin; Jordan, Michael I.

    2015-01-01

    Recent studies reveal that a deep neural network can learn transferable features which generalize well to novel tasks for domain adaptation. However, as deep features eventually transition from general to specific along the network, the feature transferability drops significantly in higher layers with increasing domain discrepancy. Hence, it is important to formally reduce the dataset bias and enhance the transferability in task-specific layers. In this paper, we propose a new Deep Adaptation...

  13. SIFT based algorithm for point feature tracking

    Directory of Open Access Journals (Sweden)

    Adrian BURLACU

    2007-12-01

    Full Text Available In this paper a tracking algorithm for SIFT features in image sequences is developed. For each point feature extracted using SIFT algorithm a descriptor is computed using information from its neighborhood. Using an algorithm based on minimizing the distance between two descriptors tracking point features throughout image sequences is engaged. Experimental results, obtained from image sequences that capture scaling of different geometrical type object, reveal the performances of the tracking algorithm.

  14. Mining Videos for Features that Drive Attention

    Science.gov (United States)

    2015-04-01

    that can be added or removed from the final saliency computation. Examples of these features include intensity contrast, motion energy , color opponent...corresponding to the image. Each pixel in the feature map indicates the energy that the feature in question contributes at that location. In the standard...eye and head animation using a neurobio - logical model of visual attention. In: Bosacchi B, Fogel DB, Bezdek JC (eds) Proceedings of SPIE 48th annual

  15. Radiographic features of periapical cysts and granulomas

    OpenAIRE

    Zain, R. B.; Roswati, N.; Ismail, K.

    1989-01-01

    Many studies have been reported on radiographic lesion sizes of periapical lesions. However no studies have been reported on prevalences of subjective radiographic features in these lesions except for the early assumption that a periapical cyst usually exhibit a radiopaque cortex. This study is conducted to evaluate the prevalences of several subjective radiographic features of periapical cysts and granulomas in the hope to identify features that maybe suggestive of either diagnosis. The resu...

  16. PROBLEMATIC FEATURES OF THE POLITICAL DECISION MAKERS

    OpenAIRE

    Aleksey Sergeevih Voynov

    2014-01-01

    Purpose: identify the most important features in the process of making political decisions that affect the effectiveness of problem-solving situationsScientific novelty: as a result of the analysis identified the problematic features of major importance for the efficiency of the development and adoption of the most rational solution to a problem situation.Results: the analysis of the most significant features affecting the quality of decisions among them the interest of the person making deci...

  17. Recognition of handwritten characters using local gradient feature descriptors

    NARCIS (Netherlands)

    Surinta, Olarik; Karaaba, Mahir F.; Schomaker, Lambert R.B.; Wiering, Marco A.

    2015-01-01

    Abstract In this paper we propose to use local gradient feature descriptors, namely the scale invariant feature transform keypoint descriptor and the histogram of oriented gradients, for handwritten character recognition. The local gradient feature descriptors are used to extract feature vectors

  18. MetaFIND: A feature analysis tool for metabolomics data

    Directory of Open Access Journals (Sweden)

    Cunningham Pádraig

    2008-11-01

    Full Text Available Abstract Background Metabolomics, or metabonomics, refers to the quantitative analysis of all metabolites present within a biological sample and is generally carried out using NMR spectroscopy or Mass Spectrometry. Such analysis produces a set of peaks, or features, indicative of the metabolic composition of the sample and may be used as a basis for sample classification. Feature selection may be employed to improve classification accuracy or aid model explanation by establishing a subset of class discriminating features. Factors such as experimental noise, choice of technique and threshold selection may adversely affect the set of selected features retrieved. Furthermore, the high dimensionality and multi-collinearity inherent within metabolomics data may exacerbate discrepancies between the set of features retrieved and those required to provide a complete explanation of metabolite signatures. Given these issues, the latter in particular, we present the MetaFIND application for 'post-feature selection' correlation analysis of metabolomics data. Results In our evaluation we show how MetaFIND may be used to elucidate metabolite signatures from the set of features selected by diverse techniques over two metabolomics datasets. Importantly, we also show how MetaFIND may augment standard feature selection and aid the discovery of additional significant features, including those which represent novel class discriminating metabolites. MetaFIND also supports the discovery of higher level metabolite correlations. Conclusion Standard feature selection techniques may fail to capture the full set of relevant features in the case of high dimensional, multi-collinear metabolomics data. We show that the MetaFIND 'post-feature selection' analysis tool may aid metabolite signature elucidation, feature discovery and inference of metabolic correlations.

  19. Interactive music composition driven by feature evolution.

    Science.gov (United States)

    Kaliakatsos-Papakostas, Maximos A; Floros, Andreas; Vrahatis, Michael N

    2016-01-01

    Evolutionary music composition is a prominent technique for automatic music generation. The immense adaptation potential of evolutionary algorithms has allowed the realisation of systems that automatically produce music through feature and interactive-based composition approaches. Feature-based composition employs qualitatively descriptive music features as fitness landmarks. Interactive composition systems on the other hand, derive fitness directly from human ratings and/or selection. The paper at hand introduces a methodological framework that combines the merits of both evolutionary composition methodologies. To this end, a system is presented that is organised in two levels: the higher level of interaction and the lower level of composition. The higher level incorporates the particle swarm optimisation algorithm, along with a proposed variant and evolves musical features according to user ratings. The lower level realizes feature-based music composition with a genetic algorithm, according to the top level features. The aim of this work is not to validate the efficiency of the currently utilised setup in each level, but to examine the convergence behaviour of such a two-level technique in an objective manner. Therefore, an additional novelty in this work concerns the utilisation of artificial raters that guide the system through the space of musical features, allowing the exploration of its convergence characteristics: does the system converge to optimal melodies, is this convergence fast enough for potential human listeners and is the trajectory to convergence "interesting' and "creative" enough? The experimental results reveal that the proposed methodological framework represents a fruitful and robust, novel approach to interactive music composition.

  20. Feature-aware natural texture synthesis

    KAUST Repository

    Wu, Fuzhang

    2014-12-04

    This article presents a framework for natural texture synthesis and processing. This framework is motivated by the observation that given examples captured in natural scene, texture synthesis addresses a critical problem, namely, that synthesis quality can be affected adversely if the texture elements in an example display spatially varied patterns, such as perspective distortion, the composition of different sub-textures, and variations in global color pattern as a result of complex illumination. This issue is common in natural textures and is a fundamental challenge for previously developed methods. Thus, we address it from a feature point of view and propose a feature-aware approach to synthesize natural textures. The synthesis process is guided by a feature map that represents the visual characteristics of the input texture. Moreover, we present a novel adaptive initialization algorithm that can effectively avoid the repeat and verbatim copying artifacts. Our approach improves texture synthesis in many images that cannot be handled effectively with traditional technologies.

  1. Histological image classification using biologically interpretable shape-based features

    International Nuclear Information System (INIS)

    Kothari, Sonal; Phan, John H; Young, Andrew N; Wang, May D

    2013-01-01

    Automatic cancer diagnostic systems based on histological image classification are important for improving therapeutic decisions. Previous studies propose textural and morphological features for such systems. These features capture patterns in histological images that are useful for both cancer grading and subtyping. However, because many of these features lack a clear biological interpretation, pathologists may be reluctant to adopt these features for clinical diagnosis. We examine the utility of biologically interpretable shape-based features for classification of histological renal tumor images. Using Fourier shape descriptors, we extract shape-based features that capture the distribution of stain-enhanced cellular and tissue structures in each image and evaluate these features using a multi-class prediction model. We compare the predictive performance of the shape-based diagnostic model to that of traditional models, i.e., using textural, morphological and topological features. The shape-based model, with an average accuracy of 77%, outperforms or complements traditional models. We identify the most informative shapes for each renal tumor subtype from the top-selected features. Results suggest that these shapes are not only accurate diagnostic features, but also correlate with known biological characteristics of renal tumors. Shape-based analysis of histological renal tumor images accurately classifies disease subtypes and reveals biologically insightful discriminatory features. This method for shape-based analysis can be extended to other histological datasets to aid pathologists in diagnostic and therapeutic decisions

  2. Grammar-based feature generation for time-series prediction

    CERN Document Server

    De Silva, Anthony Mihirana

    2015-01-01

    This book proposes a novel approach for time-series prediction using machine learning techniques with automatic feature generation. Application of machine learning techniques to predict time-series continues to attract considerable attention due to the difficulty of the prediction problems compounded by the non-linear and non-stationary nature of the real world time-series. The performance of machine learning techniques, among other things, depends on suitable engineering of features. This book proposes a systematic way for generating suitable features using context-free grammar. A number of feature selection criteria are investigated and a hybrid feature generation and selection algorithm using grammatical evolution is proposed. The book contains graphical illustrations to explain the feature generation process. The proposed approaches are demonstrated by predicting the closing price of major stock market indices, peak electricity load and net hourly foreign exchange client trade volume. The proposed method ...

  3. Treatment recommendations for DSM-5-defined mixed features.

    Science.gov (United States)

    Rosenblat, Joshua D; McIntyre, Roger S

    2017-04-01

    The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) mixed features specifier provides a less restrictive definition of mixed mood states, compared to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR), including mood episodes that manifest with subthreshold symptoms of the opposite mood state. A limited number of studies have assessed the efficacy of treatments specifically for DSM-5-defined mixed features in mood disorders. As such, there is currently an inadequate amount of data to appropriately inform evidence-based treatment guidelines of DSM-5 defined mixed features. However, given the high prevalence and morbidity of mixed features, treatment recommendations based on the currently available evidence along with expert opinion may be of benefit. This article serves to provide these interim treatment recommendations while humbly acknowledging the limited amount of evidence currently available. Second-generation antipsychotics (SGAs) appear to have the greatest promise in the treatment of bipolar disorder (BD) with mixed features. Conventional mood stabilizing agents (ie, lithium and divalproex) may also be of benefit; however, they have been inadequately studied. In the treatment of major depressive disorder (MDD) with mixed features, the comparable efficacy of antidepressants versus other treatments, such as SGAs, remains unknown. As such, antidepressants remain first-line treatment of MDD with or without mixed features; however, there are significant safety concerns associated with antidepressant monotherapy when mixed features are present, which merits increased monitoring. Lurasidone is the only SGA monotherapy that has been shown to be efficacious specifically in the treatment of MDD with mixed features. Further research is needed to accurately determine the efficacy, safety, and tolerability of treatments specifically for mood episodes with mixed features to adequately inform

  4. A feature dictionary supporting a multi-domain medical knowledge base.

    Science.gov (United States)

    Naeymi-Rad, F

    1989-01-01

    Because different terminology is used by physicians of different specialties in different locations to refer to the same feature (signs, symptoms, test results), it is essential that our knowledge development tools provide a means to access a common pool of terms. This paper discusses the design of an online medical dictionary that provides a solution to this problem for developers of multi-domain knowledge bases for MEDAS (Medical Emergency Decision Assistance System). Our Feature Dictionary supports phrase equivalents for features, feature interactions, feature classifications, and translations to the binary features generated by the expert during knowledge creation. It is also used in the conversion of a domain knowledge to the database used by the MEDAS inference diagnostic sessions. The Feature Dictionary also provides capabilities for complex queries across multiple domains using the supported relations. The Feature Dictionary supports three methods for feature representation: (1) for binary features, (2) for continuous valued features, and (3) for derived features.

  5. Online Feature Selection for Classifying Emphysema in HRCT Images

    Directory of Open Access Journals (Sweden)

    M. Prasad

    2008-06-01

    Full Text Available Feature subset selection, applied as a pre- processing step to machine learning, is valuable in dimensionality reduction, eliminating irrelevant data and improving classifier performance. In the classic formulation of the feature selection problem, it is assumed that all the features are available at the beginning. However, in many real world problems, there are scenarios where not all features are present initially and must be integrated as they become available. In such scenarios, online feature selection provides an efficient way to sort through a large space of features. It is in this context that we introduce online feature selection for the classification of emphysema, a smoking related disease that appears as low attenuation regions in High Resolution Computer Tomography (HRCT images. The technique was successfully evaluated on 61 HRCT scans and compared with different online feature selection approaches, including hill climbing, best first search, grafting, and correlation-based feature selection. The results were also compared against ldensity maskr, a standard approach used for emphysema detection in medical image analysis.

  6. Feature Selection via Chaotic Antlion Optimization.

    Directory of Open Access Journals (Sweden)

    Hossam M Zawbaa

    Full Text Available Selecting a subset of relevant properties from a large set of features that describe a dataset is a challenging machine learning task. In biology, for instance, the advances in the available technologies enable the generation of a very large number of biomarkers that describe the data. Choosing the more informative markers along with performing a high-accuracy classification over the data can be a daunting task, particularly if the data are high dimensional. An often adopted approach is to formulate the feature selection problem as a biobjective optimization problem, with the aim of maximizing the performance of the data analysis model (the quality of the data training fitting while minimizing the number of features used.We propose an optimization approach for the feature selection problem that considers a "chaotic" version of the antlion optimizer method, a nature-inspired algorithm that mimics the hunting mechanism of antlions in nature. The balance between exploration of the search space and exploitation of the best solutions is a challenge in multi-objective optimization. The exploration/exploitation rate is controlled by the parameter I that limits the random walk range of the ants/prey. This variable is increased iteratively in a quasi-linear manner to decrease the exploration rate as the optimization progresses. The quasi-linear decrease in the variable I may lead to immature convergence in some cases and trapping in local minima in other cases. The chaotic system proposed here attempts to improve the tradeoff between exploration and exploitation. The methodology is evaluated using different chaotic maps on a number of feature selection datasets. To ensure generality, we used ten biological datasets, but we also used other types of data from various sources. The results are compared with the particle swarm optimizer and with genetic algorithm variants for feature selection using a set of quality metrics.

  7. Features Selection for Skin Micro-Image Symptomatic Recognition

    Institute of Scientific and Technical Information of China (English)

    HUYue-li; CAOJia-lin; ZHAOQian; FENGXu

    2004-01-01

    Automatic recognition of skin micro-image symptom is important in skin diagnosis and treatment. Feature selection is to improve the classification performance of skin micro-image symptom.This paper proposes a hybrid approach based on the support vector machine (SVM) technique and genetic algorithm (GA) to select an optimum feature subset from the feature group extracted from the skin micro-images. An adaptive GA is introduced for maintaining the convergence rate. With the proposed method, the average cross validation accuracy is increased from 88.25% using all features to 96.92% using only selected features provided by a classifier for classification of 5 classes of skin symptoms. The experimental results are satisfactory.

  8. Features Selection for Skin Micro-Image Symptomatic Recognition

    Institute of Scientific and Technical Information of China (English)

    HU Yue-li; CAO Jia-lin; ZHAO Qian; FENG Xu

    2004-01-01

    Automatic recognition of skin micro-image symptom is important in skin diagnosis and treatment. Feature selection is to improve the classification performance of skin micro-image symptom.This paper proposes a hybrid approach based on the support vector machine (SVM) technique and genetic algorithm (GA) to select an optimum feature subset from the feature group extracted from the skin micro-images. An adaptive GA is introduced for maintaining the convergence rate. With the proposed method, the average cross validation accuracy is increased from 88.25% using all features to 96.92 % using only selected features provided by a classifier for classification of 5 classes of skin symptoms. The experimental results are satisfactory.

  9. Teaching World Music through Feature Films

    Science.gov (United States)

    Lum, Chee-Hoo

    2009-01-01

    When used effectively, feature films can bring a plethora of visual and aural stimulation to students and enhance their learning about world cultures. Feature films can take students to places, sights, and sounds that they have yet to experience. After watching these films, students might become new admirers or even keen followers of the subject…

  10. Recent Development of the Two-Stroke Engine. II - Design Features. 2; Design Features

    Science.gov (United States)

    Zeman, J.

    1945-01-01

    Completing the first paper dealing with charging methods and arrangements, the present paper discusses the design forms of two-stroke engines. Features which largely influence piston running are: (a) The shape and surface condition of the sliding parts. (b) The cylinder and piston materials. (c) Heat conditions in the piston, and lubrication. There is little essential difference between four-stroke and two-stroke engines with ordinary pistons. In large engines, for example, are always found separately cast or welded frames in which the stresses are taken up by tie rods. Twin piston and timing piston engines often differ from this design. Examples can be found in many engines of German or foreign make. Their methods of operation will be dealt with in the third part of the present paper, which also includes the bibliography. The development of two-stroke engine design is, of course, mainly concerned with such features as are inherently difficult to master; that is, the piston barrel and the design of the gudgeon pin bearing. Designers of four-stroke engines now-a-days experience approximately the same difficulties, since heat stresses have increased to the point of influencing conditions in the piston barrel. Features which notably affect this are: (a) The material. (b) Prevailing heat conditions.

  11. New features of the Helioviewer Project

    Science.gov (United States)

    Ireland, J.; Zahniy, S.; Nicula, B.; Mueller, D.; Felix, S.; Verstringe, F.; Bourgoignie, B.

    2016-12-01

    This year saw the release of major new upgrades to the capabilities of helioviewer.org and JHelioviewer. The helioviewer.org interface was completely re-designed, and now provides image and feature/event time-lines and data download capabilities. JHelioviewer introduced interactive time-series, the ability to query different servers for different data, and image reprojection. We introduce the new features of these software releases and give use cases. We will summarize our latest usage statistics, and discuss what's coming up next for the Helioviewer Project. We will also be soliciting bug reports, requests for new features and comments on the effectiveness of helioviewer.org and JHelioviewer. What would you like to see next from the Helioviewer Project?

  12. Temporal resolution for the perception of features and conjunctions.

    Science.gov (United States)

    Bodelón, Clara; Fallah, Mazyar; Reynolds, John H

    2007-01-24

    The visual system decomposes stimuli into their constituent features, represented by neurons with different feature selectivities. How the signals carried by these feature-selective neurons are integrated into coherent object representations is unknown. To constrain the set of possible integrative mechanisms, we quantified the temporal resolution of perception for color, orientation, and conjunctions of these two features. We find that temporal resolution is measurably higher for each feature than for their conjunction, indicating that time is required to integrate features into a perceptual whole. This finding places temporal limits on the mechanisms that could mediate this form of perceptual integration.

  13. Feature Binding and the Hebb Repetition Effect

    OpenAIRE

    Barrett, Maeve

    2008-01-01

    Previous studies have found no evidence that long-term learning of integrated objects and individual features benefit visual short term memory tasks (Logie, Brockmole, & Vandenbroucke, in press; Olson & Jiang, 2004; Treisman, 2006). These findings may have been due to stimulus interference as a restricted number of features were utilised in these studies to form objects in the stimulus arrays. In these studies, participants would have needed to break apart the features of several objects in a...

  14. Optimized feature subsets for epileptic seizure prediction studies.

    Science.gov (United States)

    Direito, Bruno; Ventura, Francisco; Teixeira, César; Dourado, António

    2011-01-01

    The reduction of the number of EEG features to give as inputs to epilepsy seizure predictors is a needed step towards the development of a transportable device for real-time warning. This paper presents a comparative study of three feature selection methods, based on Support Vector Machines. Minimum-Redundancy Maximum-Relevance, Recursive Feature Elimination, Genetic Algorithms, show that, for three patients of the European Database on Epilepsy, the most important univariate features are related to spectral information and statistical moments.

  15. Imaging features of thalassemia

    Energy Technology Data Exchange (ETDEWEB)

    Tunaci, M.; Tunaci, A.; Engin, G.; Oezkorkmaz, B.; Acunas, G.; Acunas, B. [Dept. of Radiology, Istanbul Univ. (Turkey); Dincol, G. [Dept. of Internal Medicine, Istanbul Univ. (Turkey)

    1999-07-01

    Thalassemia is a kind of chronic, inherited, microcytic anemia characterized by defective hemoglobin synthesis and ineffective erythropoiesis. In all thalassemias clinical features that result from anemia, transfusional, and absorptive iron overload are similar but vary in severity. The radiographic features of {beta}-thalassemia are due in large part to marrow hyperplasia. Markedly expanded marrow space lead to various skeletal manifestations including spine, skull, facial bones, and ribs. Extramedullary hematopoiesis (ExmH), hemosiderosis, and cholelithiasis are among the non-skeletal manifestations of thalassemia. The skeletal X-ray findings show characteristics of chronic overactivity of the marrow. In this article both skeletal and non-skeletal manifestations of thalassemia are discussed with an overview of X-ray findings, including MRI and CT findings. (orig.)

  16. Imaging features of thalassemia

    International Nuclear Information System (INIS)

    Tunaci, M.; Tunaci, A.; Engin, G.; Oezkorkmaz, B.; Acunas, G.; Acunas, B.; Dincol, G.

    1999-01-01

    Thalassemia is a kind of chronic, inherited, microcytic anemia characterized by defective hemoglobin synthesis and ineffective erythropoiesis. In all thalassemias clinical features that result from anemia, transfusional, and absorptive iron overload are similar but vary in severity. The radiographic features of β-thalassemia are due in large part to marrow hyperplasia. Markedly expanded marrow space lead to various skeletal manifestations including spine, skull, facial bones, and ribs. Extramedullary hematopoiesis (ExmH), hemosiderosis, and cholelithiasis are among the non-skeletal manifestations of thalassemia. The skeletal X-ray findings show characteristics of chronic overactivity of the marrow. In this article both skeletal and non-skeletal manifestations of thalassemia are discussed with an overview of X-ray findings, including MRI and CT findings. (orig.)

  17. Identification of DNA-Binding Proteins Using Mixed Feature Representation Methods.

    Science.gov (United States)

    Qu, Kaiyang; Han, Ke; Wu, Song; Wang, Guohua; Wei, Leyi

    2017-09-22

    DNA-binding proteins play vital roles in cellular processes, such as DNA packaging, replication, transcription, regulation, and other DNA-associated activities. The current main prediction method is based on machine learning, and its accuracy mainly depends on the features extraction method. Therefore, using an efficient feature representation method is important to enhance the classification accuracy. However, existing feature representation methods cannot efficiently distinguish DNA-binding proteins from non-DNA-binding proteins. In this paper, a multi-feature representation method, which combines three feature representation methods, namely, K-Skip-N-Grams, Information theory, and Sequential and structural features (SSF), is used to represent the protein sequences and improve feature representation ability. In addition, the classifier is a support vector machine. The mixed-feature representation method is evaluated using 10-fold cross-validation and a test set. Feature vectors, which are obtained from a combination of three feature extractions, show the best performance in 10-fold cross-validation both under non-dimensional reduction and dimensional reduction by max-relevance-max-distance. Moreover, the reduced mixed feature method performs better than the non-reduced mixed feature technique. The feature vectors, which are a combination of SSF and K-Skip-N-Grams, show the best performance in the test set. Among these methods, mixed features exhibit superiority over the single features.

  18. Identification of DNA-Binding Proteins Using Mixed Feature Representation Methods

    Directory of Open Access Journals (Sweden)

    Kaiyang Qu

    2017-09-01

    Full Text Available DNA-binding proteins play vital roles in cellular processes, such as DNA packaging, replication, transcription, regulation, and other DNA-associated activities. The current main prediction method is based on machine learning, and its accuracy mainly depends on the features extraction method. Therefore, using an efficient feature representation method is important to enhance the classification accuracy. However, existing feature representation methods cannot efficiently distinguish DNA-binding proteins from non-DNA-binding proteins. In this paper, a multi-feature representation method, which combines three feature representation methods, namely, K-Skip-N-Grams, Information theory, and Sequential and structural features (SSF, is used to represent the protein sequences and improve feature representation ability. In addition, the classifier is a support vector machine. The mixed-feature representation method is evaluated using 10-fold cross-validation and a test set. Feature vectors, which are obtained from a combination of three feature extractions, show the best performance in 10-fold cross-validation both under non-dimensional reduction and dimensional reduction by max-relevance-max-distance. Moreover, the reduced mixed feature method performs better than the non-reduced mixed feature technique. The feature vectors, which are a combination of SSF and K-Skip-N-Grams, show the best performance in the test set. Among these methods, mixed features exhibit superiority over the single features.

  19. The inositol-1,2-cyclic phosphate moiety of the cross-reacting determinant, carbohydrate chains, and proteinaceous components are all responsible for the cross-reactivity of trypanosome variant surface glycoproteins.

    Science.gov (United States)

    Escalona, José L; Uzcanga, Graciela L; Carrasquel, Liomary M; Bubis, José

    2018-01-24

    Salivarian trypanosomes evade the host immune system by continually swapping their protective variant surface glycoprotein (VSG) coat. Given that VSGs from various trypanosome stocks exhibited cross-reactivity (Camargo et al., Vet. Parasitol. 207, 17-33, 2015), we analyzed here which components are the antigenic determinants for this cross-reaction. Soluble forms of VSGs were purified from four Venezuelan animal trypanosome isolates: TeAp-N/D1, TeAp-ElFrio01, TeAp-Mantecal01, and TeGu-Terecay323. By using the VSG soluble form from TeAp-N/D1, we found that neither the inositol-1,2-cyclic phosphate moiety of the cross-reacting determinant nor the carbohydrate chains were exclusively responsible for its cross-reactivity. Then, all four purified glycoproteins were digested with papain and the resulting peptides were separated by high-performance liquid chromatography. Dot blot evaluation of the fractions using sera from trypanosome-infected animals yielded peptides that possessed cross-reaction activity, demonstrating for the first time that proteinaceous epitopes are also responsible for the cross-reactivity of trypanosome VSGs.

  20. Low-Dimensional Feature Representation for Instrument Identification

    Science.gov (United States)

    Ihara, Mizuki; Maeda, Shin-Ichi; Ikeda, Kazushi; Ishii, Shin

    For monophonic music instrument identification, various feature extraction and selection methods have been proposed. One of the issues toward instrument identification is that the same spectrum is not always observed even in the same instrument due to the difference of the recording condition. Therefore, it is important to find non-redundant instrument-specific features that maintain information essential for high-quality instrument identification to apply them to various instrumental music analyses. For such a dimensionality reduction method, the authors propose the utilization of linear projection methods: local Fisher discriminant analysis (LFDA) and LFDA combined with principal component analysis (PCA). After experimentally clarifying that raw power spectra are actually good for instrument classification, the authors reduced the feature dimensionality by LFDA or by PCA followed by LFDA (PCA-LFDA). The reduced features achieved reasonably high identification performance that was comparable or higher than those by the power spectra and those achieved by other existing studies. These results demonstrated that our LFDA and PCA-LFDA can successfully extract low-dimensional instrument features that maintain the characteristic information of the instruments.