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Sample records for coordination valences

  1. Bond—Valence Sum and Distortion of Coordination Polyhedra

    Institute of Scientific and Technical Information of China (English)

    章礼明

    1993-01-01

    By using the Lagrange's intermediate value theorem,it is derived mathematically that the structur-al distortion of a coordination polyhedron may lead to an increase in bond-valence sum of the cen-tral atom of ion .The applicabilities of the bond-valence model are discussed in the following two cases:the modeling of crystal structure ,and the indication of distortion degree of a coordination polyhedron.Also it is shown that a distorted polyhedron should be in favor of a longer average bond length or a smaller coordination number.

  2. Valence-Bond Concepts in Coordination Chemistry and the Nature of Metal-Metal Bonds.

    Science.gov (United States)

    Pauling, Linus; Herman, Zelek S.

    1984-01-01

    Discusses the valence-bond method, applying it to some coordination compounds of metals, especially those involving metal-metal bonds. Suggests that transition metals can form as many as nine covalent bonds, permitting valence-theory to be extended to transition metal compounds in a more effective way than has been possible before. (JN)

  3. The use of symmetrized valence and relative motion coordinates for crystal potentials

    DEFF Research Database (Denmark)

    McMurry, H. L.; Hansen, Flemming Yssing

    1980-01-01

    Symmetrized valence coordinates are linear combinations of conventional valence coordinates which display the symmetry of a set of atoms bound by the valence bonds. Relative motion coordinates are relative translations, or relative rotations, of two or more strongly bonded groups of atoms among...... which relatively weak forces act. They are useful for expressing interactions between molecules in molecular crystals and should be chosen, also, to reflect the symmetry of the interacting groups. Since coordinates defined by these procedures possess elements of symmetry in common with the bonding...... interaction constants coupling coordinates of unlike symmetry with regard to the crystal point group are necessarily zero. They may be small, also, for coordinates which belong to different representations of the local symmetry when this is not the same as for the crystal. Procedures are given for defining...

  4. The valence and coordination of titanium in ordinary and enstatite chondrites

    Science.gov (United States)

    Simon, Steven B.; Sutton, Stephen R.; Grossman, Lawrence

    2016-09-01

    One way to better understand processes related to chondrite metamorphism is to evaluate changes in chondrite features as a function of petrologic type. Toward this end the valence and coordination of Ti in olivine and pyroxene in suites of ordinary (H, L, and LL) and enstatite (EH and EL) chondrites of types 3 through 6 have been determined with XANES spectroscopy. Trivalent Ti, typically 10-40% of the Ti in the analytical volumes, was found in ordinary chondrites of all types, despite the stability of oxidized iron in the samples. Average valences and the proportions of Ti that are in tetrahedral coordination generally decrease with increasing grade between types 3.0 and 3.5, increase from 3.5 to 4, and then level off. These trends are consistent with previous studies of chondrite oxidation states using other methods, except here the onset of oxidation is observed at a lower type, ∼3.5, than previously indicated (4). These results are also consistent with previous suggestions that oxidation of higher-grade ordinary chondrite samples involved exposure to aqueous fluids from melting of accreted ice. In the enstatite chondrites, typically 20-90% of the Ti is trivalent Ti, so it is reduced compared to Ti in the ordinary chondrites. Valence decreases slightly from petrologic type 3 to 4 and increases from 4 to 6, but no increases in tetrahedral coordination with petrologic type are observed, indicating a redox environment or process distinct from that of ordinary chondrite metamorphism. The presence of Ti4+ in the E chondrites supports previous suggestions that they formed from oxidized precursors that underwent reduction. Unlike ordinary chondrites, enstatite chondrites are thought to have been derived from a body or bodies that did not accrete ice, which could account for their different valence-coordination-petrologic type relationships. The hypothesis, based on observations of unmetamorphosed chondrules and supported by laboratory experiments, that equilibration

  5. Anharmonic Vibrational Treatment Exclusively in Curvilinear Valence Coordinates: The Case of Formamide.

    Science.gov (United States)

    Richter, F; Thaunay, F; Lauvergnat, D; Carbonnière, P

    2015-12-01

    A highly correlated approach using curvilinear valence coordinates is applied to calculate the vibrational fundamentals and some combination modes of the formamide molecule with high accuracy. A series of potential energy surfaces (PESs) has been generated by AGAPES, a program for adaptive generation of adiabatic PESs, at various electronic structure qualities until excellent nonaccidental agreement with the experimentally assigned fundamental transitions was reached at the CCSDT(T)-F12a/aug-cc-pVTZ level of theory using the improved relaxation method of the Heidelberg multiconfiguration time-dependent Hartree (MCTDH) package in connection with an exact expression for the kinetic energy in valence coordinates generated by the TANA program. By comparison of the overtone series ν1-3ν1 to experiment, we demonstrate that the known problems concerning the floppy ν1 wagging motion are solved within this approach. The potential energy coupling as well as the vibrational coupling in curvilinear coordinates is discussed together with the efficiency of this approach.

  6. Effects of Metamorphism on the Valence and Coordination of Titanium in Ordinary Chondrites

    Energy Technology Data Exchange (ETDEWEB)

    Simon, S.B.; Sutton, S.R.; Grossman, L. (UC)

    2012-04-02

    Despite years of study, the conditions under which ordinary chondrites were metamorphosed from grade 3 to grade 6 are not well defined. Wide ranges of peak temperature are inferred for each grade. The long-popular 'onion shell' model, in which higher metamorphic grade is attributed to greater depths of origin, implies a corresponding decrease in cooling rate with increasing grade, and there is disagreement as to whether or not this is observed. Redox conditions during chondrite metamorphism are also not well understood. Some workers have reported evidence for reduction, presumably by carbon, with increase in grade from 3-4, followed by oxidation during metamorphism to higher grades, but other work indicates little variation in fO{sub 2} as a function of metamorphic grade. During our investigation of the valence of Ti in planetary materials, we found high proportions of Ti{sup 3+} in olivine and pyroxene in chondrules in Semarkona (LL3.0) and low proportions in New Concord (L6) olivine, suggesting that Ti was oxidized during ordinary chondrite metamorphism. We have undertaken a study of L and LL chondrites of grades 3-6 to see how Ti valence and coordination vary with grade and to see if the variations can be used to constrain conditions of chondrite metamorphism.

  7. X-ray Emission Spectroscopy to Study Ligand Valence Orbitals in Mn Coordination Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Smolentsev, Grigory; Soldatov, Alexander V; Messinger, Johannes; Merz, Kathrin; Weyhermuller, Thomas; Bergmann, Uwe; Pushkar, Yulia; Yano, Junko; Yachandra, Vittal K.; Glatzel, Pieter

    2009-03-02

    We discuss a spectroscopic method to determine the character of chemical bonding and for the identification of metal ligands in coordination and bioinorganic chemistry. It is based on the analysis of satellite lines in X-ray emission spectra that arise from transitions between valence orbitals and the metal ion 1s level (valence-to-core XES). The spectra, in connection with calculations based on density functional theory (DFT), provide information that is complementary to other spectroscopic techniques, in particular X-ray absorption (XANES and EXAFS). The spectral shape is sensitive to protonation of ligands and allows ligands, which differ only slightly in atomic number (e.g., C, N, O...), to be distinguished. A theoretical discussion of the main spectral features is presented in terms of molecular orbitals for a series of Mn model systems: [Mn(H2O)6]2+, [Mn(H2O)5OH]+, [Mn(H2O)5NH2]+, and [Mn(H2O)5NH3]2+. An application of the method, with comparison between theory and experiment, is presented for the solvated Mn2+ ion in water and three Mn coordination complexes, namely [LMn(acac)N3]BPh4, [LMn(B2O3Ph2)(ClO4)], and [LMn(acac)N]BPh4, where L represents 1,4,7-trimethyl-1,4,7-triazacyclononane, acac stands for the 2,4-pentanedionate anion, and B2O3Ph2 represents the 1,3-diphenyl-1,3-dibora-2-oxapropane-1,3-diolato dianion.

  8. Coordination and metalation bifunctionality of Cu with 5,10,15,20-tetra(4-pyridyl)porphyrin: toward a mixed-valence two-dimensional coordination network.

    Science.gov (United States)

    Li, Yang; Xiao, Jie; Shubina, Tatyana E; Chen, Min; Shi, Ziliang; Schmid, Martin; Steinrück, Hans-Peter; Gottfried, J Michael; Lin, Nian

    2012-04-11

    We investigated the coordination self-assembly and metalation reaction of Cu with 5,10,15,20-tetra(4-pyridyl)porphyrin (2HTPyP) on a Au(111) surface by means of scanning tunneling microscopy, X-ray photoelectron spectroscopy, and density functional theory calculations. 2HTPyP was found to interact with Cu through both the peripheral pyridyl groups and the porphyrin core. Pairs of pyridyl groups from neighboring molecules coordinate Cu(0) atoms, which leads to the formation of a supramolecular metal-organic coordination network. The network formation occurs at room temperature; annealing at 450 K enhances the process. The interaction of Cu with the porphyrin core is more complex. At room temperature, formation of an initial complex Cu(0)-2HTPyP is observed. Annealing at 450 K activates an intramolecular redox reaction, by which the coordinated Cu(0) is oxidized to Cu(II) and the complex Cu(II)TPyP is formed. The coordination network consists then of Cu(II) complexes linked by Cu(0) atoms; that is, it represents a mixed-valence two-dimensional coordination network consisting of an ordered array of Cu(II) and Cu(0) centers. Above 520 K, the network degrades and the Cu atoms in the linking positions diffuse into the substrate, while the Cu(II)TPyP complexes form a close-packed structure that is stabilized by weak intermolecular interactions. Density functional theory investigations show that the reaction with Cu(0) proceeds via formation of an initial complex between metal atom and porphyrin followed by formation of Cu(II) porphyrin within the course of the reaction. The activation barrier of the rate limiting step was found to be 24-37 kcal mol(-1) depending on the method used. In addition, linear coordination of a Cu atom by two CuTPyP molecules is favorable according to gas-phase calculations. © 2012 American Chemical Society

  9. Mixed-valence copper coordination polymers based on CuSCN or CuN3 as bridging motifs

    Institute of Scientific and Technical Information of China (English)

    FAN Guang; GAO Shengli; CHEN Sanping; ZENG Minghua; XIE Gang

    2005-01-01

    Two novel mixed valence copper coordination polymers, [Cu(2-pac)2(CuN3)(H2O)]n (1) and [Cu(2-pac)2(CuSCN)2]n (2), have been prepared through hydrothermal synthesis and analyzed for structure determination, which exhibit two- and three-dimensional structures respectively. In complex (1), zigzag chains of [CuN3]n running parallel to the c direction are interconnected by Cu(2pac)2 to form a two-dimensional layer structure. In complex (2), the arrangement of μ-1,1,3 bridging thiocyanate ligand leads to the formation of ten-membered Cu-SCN- Cu-S-Cu-NCS rings, and each Cu atom is further linked by Cu(2-pac)2 to afford a three-dimensional configuration.

  10. Intramolecular hydrogen bond: Can it be part of the basis set of valence internal coordinates in normal mode analysis?

    Indian Academy of Sciences (India)

    Sarvesh Kumar Pandey; Prasanta Das; Puspendu K Das; Elangannan Arunan; Sadasivam Manogaran

    2015-06-01

    It has been shown earlier1 that the relaxed force constants (RFCs) could be used as a measure of bond strength only when the bonds form a part of the complete valence internal coordinates (VIC) basis. However, if the bond is not a part of the complete VIC basis, its RFC is not necessarily a measure of bond strength. Sometimes, it is possible to have a complete VIC basis that does not contain the intramolecular hydrogen bond (IMHB) as part of the basis. This means the RFC of IMHB is not necessarily a measure of bond strength. However, we know that IMHB is a weak bond and hence its RFC has to be a measure of bond strength. We resolve this problem of IMHB not being part of the complete basis by postulating `equivalent’ basis sets where IMHB is part of the basis at least in one of the equivalent sets of VIC. As long as a given IMHB appears in one of the equivalent complete VIC basis sets, its RFC could be used as a measure of bond strength parameter.

  11. Complementary method to locate atomic coordinates by combined searching method of structure-sensitive indexes based on bond valence method

    Institute of Scientific and Technical Information of China (English)

    宋振; 刘小浪; 何丽珠; 夏志国; 刘泉林

    2015-01-01

    Bond valence method illustrates the relation between valence and length of a particular bond type. This theory has been used to predict structure information, but the effect is very limited. In this paper, two indexes, i.e., global instability index (GII) and bond strain index (BSI), are adopted as a judgment of a search-match program for prediction. The results show that with GII and BSI combined as judgment, the predicted atom positions are very close to real ones. The mechanism and validity of this searching program are also discussed. The GII&BSI distribution contour map reveals that the predicted function is a reflection of exponential feature of bond valence formula. This combined searching method may be integrated with other structure-determination method, and may be helpful in refining and testifying light atom positions.

  12. Synthesis, Crystal Structure, and Electroconducting Properties of a 1D Mixed-Valence Cu(I–Cu(II Coordination Polymer with a Dicyclohexyl Dithiocarbamate Ligand

    Directory of Open Access Journals (Sweden)

    Kenji Nakatani

    2015-04-01

    Full Text Available A new mixed-valence Cu(I–Cu(II 1D coordination polymer, [CuI4CuIIBr4(Cy2dtc2]n, with an infinite chain structure is synthesized by the reaction of Cu(Cy2dtc2 (Cy2dtc− = dicyclohexyl dithiocarbamate, C13H22NS2 with CuBr·S(CH32. The as-synthesized polymer consists of mononuclear copper(II units of CuII(Cy2dtc2 and tetranuclear copper(I cluster units, CuI4Br4. In the cluster unit, all the CuI ions have distorted trigonal pyramidal coordination geometries, and the CuI–CuI or CuI–CuII distances between the nearest copper ions are shorter than the sum of van der Waals radii for Cu–Cu.

  13. Mixed-valence copper(I,II) complexes with 4-(1H-pyrazol-1-yl)-6-R-pyrimidines: from ionic structures to coordination polymers.

    Science.gov (United States)

    Vinogradova, Katerina A; Krivopalov, Viktor P; Nikolaenkova, Elena B; Pervukhina, Natalia V; Naumov, Dmitrii Yu; Boguslavsky, Evgenii G; Bushuev, Mark B

    2016-01-14

    Two pyrimidine-based ligands, 4-(3,5-diphenyl-1H-pyrazol-1-yl)-6-(morpholino)pyrimidine () and 4-(3,5-diphenyl-1H-pyrazol-1-yl)-6-phenoxypyrimidine (), and a series of mixed-valence copper(i,ii) halide complexes, [Cu(L(2))2Br]2[Cu2Br4] (), [Cu(L(2))2Cl][CuCl2] (), and [Cu2L(3)Br3]n (), have been synthesized. The complex [Cu(L(2))2Br]2[Cu2Br4] was prepared by the reaction of with CuBr2 in a 1 : 1 molar ratio in MeCN. Its chlorido-analogue, the complex [Cu(L(2))2Cl][CuCl2], was synthesized by the reaction between , CuCl2 and CuCl in a 2 : 1 : 1 molar ratio in MeCN. The ligand acts as a chelating one. In the structures of the complexes [Cu(L(2))2Br]2[Cu2Br4] and [Cu(L(2))2Cl][CuCl2] the Cu(2+) ion is in the cationic part of the complex whereas the Cu(+) ion is located in the anionic part. The best way to synthesize the mixed-valence 1D coordination polymer [Cu2L(3)Br3]n is to react CuBr2 with in a 2 : 1 molar ratio in the MeCN/CHCl3 mixture on heating. In the structure of [Cu2L(3)Br3]n the ligand shows chelating/bridging tridentate coordination. This is the first example of the tridentate coordination of 4-(1H-pyrazol-1-yl)-6-R-pyrimidines. The striking difference between the coordination behavior of and (chelating bidentate vs. chelating/bridging coordination) is related with the possibility of rotation of the 6-phenoxy group around the C-O bond which makes the N(1) pyrimidine atom less sterically hindered, enabling it to participate in metal ion binding. Importantly, all copper ions in [Cu2L(3)Br3]n show similar tetrahedral environments, CuNBr3 and CuN2Br2, which is extremely rare for mixed-valence copper(i,ii) compounds. The ligands and show blue emission which is quenched upon their coordination to copper ions. The 1D coordination polymer [Cu2L(3)Br3]n shows high thermal stability and unusual solvent-occlusion properties. The role of the substituents favoring the formation of the mixed-valence copper(i,ii) complexes with 4-(1H-pyrazol-1-yl)-6-R

  14. New Variational Method for the Ab Initio Study in Valence Coordinates of the Renner-Teller Effect in Tetra-Atomic Systems.

    Science.gov (United States)

    Jutier, Laurent; Léonard, Céline

    2010-05-11

    A new variational methodology for the treatment of the Renner-Teller effect in tetra-atomic molecules has been developed in valence coordinates. The kinetic-energy operator of Bramley et al. [Mol. Phys. 1991, 73, 1183] for any sequentially bonded four-atom molecule, A-B-C-D, in the singlet nondegenerate electronic state has been adapted to the Renner-Teller and spin couplings by modifying the expression of the nuclear angular momentum. The total Schrödinger equation is solved by diagonalizing the Hamiltonian matrix in a three-step contraction scheme. The main advantage of this new theoretical development is the possibility of studying different isotopomers using the same potential-energy surfaces. This procedure has been tested on HCCH(+) and its deuterated derivatives DCCD(+) and DCCH(+). The calculated rovibronic band origins were compared with previous data deduced from the Jacobi coordinates methodology, dimensionality reduced variational treatment, and photoelectron spectra with a good global agreement. Rotational structures for these systems are also tackled.

  15. High Valence, Normal Valence and Unknown Valence

    DEFF Research Database (Denmark)

    Morsing, Thorbjørn Juul

    quality of single crystal multi frequency EPR is used to make a new model which is more physically accurate and which better describes the observed experimental behaviour. This has implications not just for the investigated chromium systems, but for exchange coupled systems in general. Chapter 3 details...... that the coordination of Ag(I) has no perceivable eect on the Ir ligand eld. Chapter 6 details the synthesis of new terminal ruthenium carbide complexes by ligand substitution on the Ru center. This approach to new, rationally tuned carbide complexes is virtually unexplored. The reaction of the known carbide complex...... [RuC(Cl)2(PCy3)2] with cyanide aords the cyanide analogue [RuC(CN)2(PCy3)2]. The reaction kinetics are studied with NMR. It is also possible to exchange only one of the chloride ligands, with the intermediate [RuC(Cl)(NCCH3)(PCy3)2]+ and this control of the ligand environment opens up the possibility...

  16. Levels of Valence

    Science.gov (United States)

    Shuman, Vera; Sander, David; Scherer, Klaus R.

    2013-01-01

    The distinction between the positive and the negative is fundamental in our emotional life. In appraisal theories, in particular in the component process model of emotion (Scherer, 1984, 2010), qualitatively different types of valence are proposed based on appraisals of (un)pleasantness, goal obstructiveness/conduciveness, low or high power, self-(in)congruence, and moral badness/goodness. This multifaceted conceptualization of valence is highly compatible with the frequent observation of mixed feelings in real life. However, it seems to contradict the one-dimensional conceptualization of valence often encountered in psychological theories, and the notion of valence as a common currency used to explain choice behavior. Here, we propose a framework to integrate the seemingly disparate conceptualizations of multifaceted valence and one-dimensional valence by suggesting that valence should be conceived at different levels, micro and macro. Micro-valences correspond to qualitatively different types of evaluations, potentially resulting in mixed feelings, whereas one-dimensional macro-valence corresponds to an integrative “common currency” to compare alternatives for choices. We propose that conceptualizing levels of valence may focus research attention on the mechanisms that relate valence at one level (micro) to valence at another level (macro), leading to new hypotheses, and addressing various concerns that have been raised about the valence concept, such as the valence-emotion relation. PMID:23717292

  17. Novel approach to the concept of bond-valence vectors.

    Science.gov (United States)

    Zachara, Janusz

    2007-11-12

    A new approach to the old idea of deriving a bond-valence vector from the well-known bond-valence concept has been proposed. The foundation of the proposal is the previous electrostatic model in which bond valences are interpreted as electric fluxes. The outcome of this approach is actual vectorial quantities whose magnitudes are strictly but nonlinearly related to the scalar bond valences and are directed along the bond lines. It has been proved that the sum of all these bond-valence vectors drawn from a coordination center to its ligating atoms will be close to zero for the complete coordination sphere. Therefore, unlike the scalar bond valences, the obtained vectors provide information about the spatial arrangement of ligands. The geometrical consequences of the proposed bond-valence vector (BVV) model are analyzed for the geometries of the carbonates, phosphates, and five-coordinated organoaluminum compounds with CO3, PO4, and AlCO4 skeletons, respectively, retrieved from the Cambridge Structural Database. For acyclic carbonates this BVV model allows one to predict the O-C-O angles with a mean absolute error of 1.0 degrees using the empirical C-O distances only. Furthermore, this BVV model is able to quantitatively describe the strains in cyclic carbonates. The preliminary studies for NO2E, PO3E, and SO3E systems with a strongly stereoactive lone electron pair (E) show that the model may serve as a quantitative description of the lone electron pair effect on the coordination sphere. A great advantage of the presented BVV approach is that the derived relation between a bond-valence vector, bond valence, and bond length is given by an uncomplicated equation allowing quick and simple computations, thus providing a new analytical tool for describing the geometry of a coordination sphere that may be applied for structure validation.

  18. Valency and molecular structure

    CERN Document Server

    Cartmell, E

    1977-01-01

    Valency and Molecular Structure, Fourth Edition provides a comprehensive historical background and experimental foundations of theories and methods relating to valency and molecular structures. In this edition, the chapter on Bohr theory has been removed while some sections, such as structures of crystalline solids, have been expanded. Details of structures have also been revised and extended using the best available values for bond lengths and bond angles. Recent developments are mostly noted in the chapter on complex compounds, while a new chapter has been added to serve as an introduction t

  19. Micro-Valences: Affective valence in neutral everyday objects

    Directory of Open Access Journals (Sweden)

    Sophie eLebrecht

    2012-04-01

    Full Text Available Affective valence influences both our cognition and our perception of the world. Indeed, the speed and quality with which we recognize objects in a visual scene can vary dramatically depending on its affective content. However, affective processing of visual objects has been typically studied using only stimuli with strong affective valences (e.g., guns or roses. Here we explore whether affective valence must be strong or obvious to exert an effect on our perception. We conclude that the majority of objects carry some affective valence (micro-valences and, thus, nominally neutral objects are not really neutral. Functionally, the perception of valence in everyday objects facilitates perceptually-driven choice behavior, decision-making, and affective responses.

  20. Characteristics of Trivalent Lanthanides in Coordination Chemistry

    Institute of Scientific and Technical Information of China (English)

    Xue Dongfeng(薛冬峰); Zuo Sen(左森); Henryk Ratajczak

    2004-01-01

    Some basic characteristics of lanthanide-oxygen bonds in various trivalent lanthanide metal-organic complexes are quantitatively studied by the bond valence model. Some important relationships among the electronegativity, bond valence parameter, bond length and lanthanide coordination number in these complexes are generally found , which show that for each trivalent lanthanide cation all calculated parameters may well be correlated with its coordination number in their coordination complexes. Specifically,32 new data for the bond valence parameter are first calculated in this work.An approximate linear relationship between the Ln-O bond valence parameter and the coordination number of Ln3+ is obtained.The Ln-O bond length increases with the increase in the lanthanide coordination number.The difference of electronegative values decreases with the increase in the lanthanide coordination number.

  1. A three-dimensional mixed-valence Cu(II)/Cu(I) coordination polymer constructed from biphenyl-3,4',5-tricarboxylate and 1,4-bis(1H-imidazol-1-yl)benzene ligands.

    Science.gov (United States)

    Liu, Ya Hui; Lu, Li Ping; Zhu, Miao Li; Su, Feng

    2016-04-01

    Coordination polymers (CPs) built by coordination bonds between metal ions/clusters and multidentate organic ligands exhibit fascinating structural topologies and potential applications as functional solid materials. The title coordination polymer, poly[diaquabis(μ4-biphenyl-3,4',5-tricarboxylato-κ(4)O(3):O(3'):O(4'):O(5))tris[μ2-1,4-bis(1H-imidazol-1-yl)benzene-κ(2)N(3):N(3')]dicopper(II)dicopper(I)], [Cu(II)2Cu(I)2(C15H7O6)2(C12H10N4)3(H2O)2]n, was crystallized from a mixture of biphenyl-3,4',5-tricarboxylic acid (H3bpt), 1,4-bis(1H-imidazol-1-yl)benzene (1,4-bib) and copper(II) chloride in a water-CH3CN mixture under solvothermal reaction conditions. The asymmetric unit consists of two crystallographically independent Cu atoms, one of which is Cu(II), while the other has been reduced to the Cu(I) ion. The Cu(II) centre is pentacoordinated by three O atoms from three bpt(3-) ligands, one N atom from a 1,4-bib ligand and one O atom from a coordinated water molecule, and the coordination geometry can be described as distorted trigonal bipyramidal. The Cu(I) atom exhibits a T-shaped geometry (CuN2O) coordinated by one O atom from a bpt(3-) ligand and two N atoms from two 1,4-bib ligands. The Cu(II) atoms are extended by bpt(3-) and 1,4-bib linkers to generate a two-dimensional network, while the Cu(I) atoms are linked by 1,4-bib ligands, forming one-dimensional chains along the [20-1] direction. In addition, the completely deprotonated μ4-η(1):η(1):η(1):η(1) bpt(3-) ligands bridge one Cu(I) and three Cu(II) cations along the a (or [100]) direction to form a three-dimensional framework with a (10(3))2(10)2(4(2).6.10(2).12)2(4(2).6.8(2).10)2(8) topology via a 2,2,3,4,4-connected net. An investigation of the magnetic properties indicated a very weak ferromagnetic behaviour.

  2. Complex materials for molecular spintronics applications: cobalt bis(dioxolene) valence tautomers, from molecules to polymers.

    Science.gov (United States)

    Calzolari, Arrigo; Chen, Yifeng; Lewis, Geoffrey F; Dougherty, Daniel B; Shultz, David; Nardelli, Marco Buongiorno

    2012-11-01

    Using first principles calculations, we predict a complex multifunctional behavior in cobalt bis(dioxolene) valence tautomeric compounds. Molecular spin-state switching is shown to dramatically alter electronic properties and corresponding transport properties. This spin state dependence has been demonstrated for technologically relevant coordination polymers of valence tautomers as well as for novel conjugated polymers with valence tautomeric functionalization. As a result, these materials are proposed as promising candidates for spintronic devices that can couple magnetic bistability with novel electrical and spin conduction properties. Our findings pave the way to the fundamental understanding and future design of active multifunctional organic materials for spintronics applications.

  3. The chemical bond in inorganic chemistry the bond valence model

    CERN Document Server

    Brown, I David

    2016-01-01

    The bond valence model is a version of the ionic model in which the chemical constraints are expressed in terms of localized chemical bonds formed by the valence charge of the atoms. Theorems derived from the properties of the electrostatic flux predict the rules obeyed by both ionic and covalent bonds. They make quantitative predictions of coordination number, crystal structure, bond lengths and bond angles. Bond stability depends on the matching of the bonding strengths of the atoms, while the conflicting requirements of chemistry and space lead to the structural instabilities responsible for the unusual physical properties displayed by some materials. The model has applications in many fields ranging from mineralogy to molecular biology.

  4. In-Medium Pion Valence Distribution Amplitude

    CERN Document Server

    Tsushima, K

    2016-01-01

    After a brief review of the quark-based model for nuclear matter, and some pion properties in medium presented in our previous works, we report new results for the pion valence wave function as well as the valence distribution amplitude in medium, which are presented in our recent article. We find that both the in-medium pion valence distribution and the in-medium pion valence wave function, are substantially modified at normal nuclear matter density, due to the reduction in the pion decay constant.

  5. In-Medium Pion Valence Distribution Amplitude

    Science.gov (United States)

    Tsushima, K.; de Melo, J. P. B. C.

    2017-03-01

    After a brief review of the quark-based model for nuclear matter, and some pion properties in medium presented in our previous works, we report new results for the pion valence wave function as well as the valence distribution amplitude in medium, which are presented in our recent article. We find that both the in-medium pion valence distribution and the in-medium pion valence wave function, are substantially modified at normal nuclear matter density, due to the reduction in the pion decay constant.

  6. Valence-Bond Theory and Chemical Structure.

    Science.gov (United States)

    Klein, Douglas J.; Trinajstic, Nenad

    1990-01-01

    Discussed is the importance of valence bond theory on the quantum-mechanical theory of chemical structure and the nature of the chemical bond. Described briefly are early VB theory, development of VB theory, modern versions, solid-state applications, models, treatment in textbooks, and flaws in criticisms of valence bond theory. (KR)

  7. Exact quantum mechanical vibration-rotation kinetic energy operator of four-particle system in various coordinates

    Institute of Scientific and Technical Information of China (English)

    陈光巨; 刘若庄

    1996-01-01

    The vibration-rotational kinetic energy operators of four-particle system in various coordinates are derived using a new and simple angular momentum method. The operators are respectively suitable for studying the systems described by scattering coordinate, valence coordinate, Radau coordinate, Radau/Jacobi and Jacobi/valence hybrid coordinates and so on. Certain properties of these operators and their possible applications are discussed.

  8. Ab initio valence calculations in chemistry

    CERN Document Server

    Cook, D B

    1974-01-01

    Ab Initio Valence Calculations in Chemistry describes the theory and practice of ab initio valence calculations in chemistry and applies the ideas to a specific example, linear BeH2. Topics covered include the Schrödinger equation and the orbital approximation to atomic orbitals; molecular orbital and valence bond methods; practical molecular wave functions; and molecular integrals. Open shell systems, molecular symmetry, and localized descriptions of electronic structure are also discussed. This book is comprised of 13 chapters and begins by introducing the reader to the use of the Schrödinge

  9. Curvilinear coordinates for full-core atoms

    Science.gov (United States)

    Putrino, Anna; Bachelet, Giovanni B.

    1998-03-01

    Curvilinear coordinates, first introduced by F. Gygi for valence-only electronic systems within the local-density functional theory (F. Gygi, Europhysics Letters 19), 617 (1992)., can be used to describe both core and valence electrons in electronic-structure calculations. A simple and quite general coordinate transformation results in a large, yet affordable plane-wave energy cutoff for full-core systems (e.g., ~= 120 Ryd for carbon or silicon) within the local-density functional theory, and in a reduced correlation time for full-core variational Monte Carlo calculations. Numerical examples will be presented.

  10. Development of Remote Plutonium Valence State Analyzer

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>In the Purex process of spent fuel reprocessing, the separation of uranium and plutonium depends on the capability extracting state plutonium ions with various valence by TBP. The separate degree of

  11. Valence space electron momentum spectroscopy of diborane

    Energy Technology Data Exchange (ETDEWEB)

    Wang Feng [Centre for Molecular Simulation, Swinburne University of Technology, P.O. Box 218, Hawthorn, Melbourne, Vic. 3122 (Australia)]. E-mail: fwang@swin.edu.au; Pang Wenning [Department of Physics, Polarization Physics Laboratory, Tsinghua University, Beijing 100084 (China); Huang Ming [Department of Physics, Polarization Physics Laboratory, Tsinghua University, Beijing 100084 (China)

    2006-05-15

    A non-classical mechanism of binding in diborane (B{sub 2} H{sub 6}) is derived quantum-mechanically (B3LYP/6-311++G**) using a dual-space analysis. High-resolution binding-energy spectra of diborane, generated using an outer-valence Green's-function and density-functional theory with a statistical average of model orbital potentials (SAOP), agree satisfactorily with experiment. Electron-correlation energies of diborane produce orbital-based variations in ionization energy in the valence space, but with negligible impact on the shape of only a{sub g} symmetry orbitals as indicated in momentum space. The present work indicates quantitatively that (a) the pair of three-centre banana-shaped B-H{sub b}-B bonds are more accurately described as one diamond-shaped bond with B-H{sub b}-B-H{sub b}, (b) all bonds in diborane are electron-deficient including the four equivalent B-H{sub t} bonds, (c) there is no pure B?B bond but contributions from all valence orbitals form an unconventional electron-deficient B-B bond, and (d) only two innermost valence orbitals - 2a{sub g} and 2b{sub 1u} - are sp{sup 2}-hybridized and no evidence indicates other valence orbitals of diborane to be hybridized.

  12. Affective Priming with Associatively Acquired Valence

    Science.gov (United States)

    Aguado, Luis; Pierna, Manuel; Saugar, Cristina

    2005-01-01

    Three experiments explored the effect of affectively congruent or incongruent primes on evaluation responses to positive or negative valenced targets (the "affective priming" effect). Experiment 1 replicated the basic affective priming effect with Spanish nouns: reaction time for evaluative responses (pleasant/unpleasant) were slower on…

  13. Emotional valence categorization using holistic image features

    NARCIS (Netherlands)

    Yanulevskaya, V.; van Gemert, J.C.; Roth, K.; Herbold, A.K.; Sebe, N.; Geusebroek, J.M.

    2008-01-01

    Can a machine learn to perceive emotions as evoked by an artwork? Here we propose an emotion categorization system, trained by ground truth from psychology studies. The training data contains emotional valences scored by human subjects on the International Affective Picture System (IAPS), a standard

  14. Masked emotional priming beyond global valence activations

    NARCIS (Netherlands)

    Rohr, M.; Degner, J.; Wentura, D.

    2012-01-01

    An immense body of research demonstrates that emotional facial expressions can be processed unconsciously. However, it has been assumed that such processing takes place solely on a global valence-based level, allowing individuals to disentangle positive from negative emotions but not the specific em

  15. Bond valence at mixed occupancy sites. I. Regular polyhedra.

    Science.gov (United States)

    Bosi, Ferdinando

    2014-10-01

    Bond valence sum calculations at mixed occupancy sites show the occurrence of systematic errors leading to apparent violations of the Valence Sum Rule (bond valence theory) in regular and unstrained bonding environments. The systematic deviation of the bond valence from the expected value is observed in the long-range structure, and is discussed from geometric and algebraic viewpoints. In the valence-length diagram, such a deviation arises from discrepancies between the intersection points of the long-range bond valences and the theoretical bond valences with the valence-length curves of involved cations. Three factors cause systematic errors in the bond valences: difference in atomic valences, bond valence parameters Ri (the length of a bond of unit valence) and bond valence parameters bi (the bond softness) between the involved cations over the same crystallographic site. One important consequence strictly related to the systematic errors is that they lead to erroneous bond strain values for mixed occupancy sites indicating underbonding or overbonding that actually does not exist.

  16. Valence-Dependent Belief Updating: Computational Validation.

    Science.gov (United States)

    Kuzmanovic, Bojana; Rigoux, Lionel

    2017-01-01

    People tend to update beliefs about their future outcomes in a valence-dependent way: they are likely to incorporate good news and to neglect bad news. However, belief formation is a complex process which depends not only on motivational factors such as the desire for favorable conclusions, but also on multiple cognitive variables such as prior beliefs, knowledge about personal vulnerabilities and resources, and the size of the probabilities and estimation errors. Thus, we applied computational modeling in order to test for valence-induced biases in updating while formally controlling for relevant cognitive factors. We compared biased and unbiased Bayesian models of belief updating, and specified alternative models based on reinforcement learning. The experiment consisted of 80 trials with 80 different adverse future life events. In each trial, participants estimated the base rate of one of these events and estimated their own risk of experiencing the event before and after being confronted with the actual base rate. Belief updates corresponded to the difference between the two self-risk estimates. Valence-dependent updating was assessed by comparing trials with good news (better-than-expected base rates) with trials with bad news (worse-than-expected base rates). After receiving bad relative to good news, participants' updates were smaller and deviated more strongly from rational Bayesian predictions, indicating a valence-induced bias. Model comparison revealed that the biased (i.e., optimistic) Bayesian model of belief updating better accounted for data than the unbiased (i.e., rational) Bayesian model, confirming that the valence of the new information influenced the amount of updating. Moreover, alternative computational modeling based on reinforcement learning demonstrated higher learning rates for good than for bad news, as well as a moderating role of personal knowledge. Finally, in this specific experimental context, the approach based on reinforcement

  17. Valence-Dependent Belief Updating: Computational Validation

    Directory of Open Access Journals (Sweden)

    Bojana Kuzmanovic

    2017-06-01

    Full Text Available People tend to update beliefs about their future outcomes in a valence-dependent way: they are likely to incorporate good news and to neglect bad news. However, belief formation is a complex process which depends not only on motivational factors such as the desire for favorable conclusions, but also on multiple cognitive variables such as prior beliefs, knowledge about personal vulnerabilities and resources, and the size of the probabilities and estimation errors. Thus, we applied computational modeling in order to test for valence-induced biases in updating while formally controlling for relevant cognitive factors. We compared biased and unbiased Bayesian models of belief updating, and specified alternative models based on reinforcement learning. The experiment consisted of 80 trials with 80 different adverse future life events. In each trial, participants estimated the base rate of one of these events and estimated their own risk of experiencing the event before and after being confronted with the actual base rate. Belief updates corresponded to the difference between the two self-risk estimates. Valence-dependent updating was assessed by comparing trials with good news (better-than-expected base rates with trials with bad news (worse-than-expected base rates. After receiving bad relative to good news, participants' updates were smaller and deviated more strongly from rational Bayesian predictions, indicating a valence-induced bias. Model comparison revealed that the biased (i.e., optimistic Bayesian model of belief updating better accounted for data than the unbiased (i.e., rational Bayesian model, confirming that the valence of the new information influenced the amount of updating. Moreover, alternative computational modeling based on reinforcement learning demonstrated higher learning rates for good than for bad news, as well as a moderating role of personal knowledge. Finally, in this specific experimental context, the approach based on

  18. Janus Nematic Colloids with Designable Valence

    Directory of Open Access Journals (Sweden)

    Simon Čopar

    2014-05-01

    Full Text Available Generalized Janus nematic colloids based on various morphologies of particle surface patches imposing homeotropic and planar surface anchoring are demonstrated. By using mesoscopic numerical modeling, multiple types of Janus particles are explored, demonstrating a variety of novel complex colloidal structures. We also show binding of Janus particles to a fixed Janus post in the nematic cell, which acts as a seed and a micro-anchor for the colloidal structure. Janus colloidal structures reveal diverse topological defect configurations, which are effectively combinations of surface boojum and bulk defects. Topological analysis is applied to defects, importantly showing that topological charge is not a well determined topological invariant in such patchy nematic Janus colloids. Finally, this work demonstrates colloidal structures with designable valence, which could allow for targeted and valence-conditioned self-assembly at micro- and nano-scale.

  19. Evaluative conditioning induces changes in sound valence

    Directory of Open Access Journals (Sweden)

    Anna C. Bolders

    2012-04-01

    Full Text Available Evaluative Conditioning (EC has hardly been tested in the auditory domain, but it is a potentially valuable research tool. In Experiment 1 we investigated whether the affective evaluation of short environmental sounds can be changed using affective words as unconditioned stimuli (US. Congruence effects on an affective priming task (APT for conditioned sounds demonstrated successful EC. Subjective ratings for sounds paired with negative words changed accordingly. In Experiment 2 we investigated whether the acquired valence remains stable after repeated presentation of the conditioned sound without the US or whether extinction occurs. The acquired affective value remained present, albeit weaker, even after 40 extinction trials. These results warrant the use of EC to study processing of short environmental sounds with acquired valence, even if this requires repeated stimulus presentations. This paves the way for studying processing of affective environmental sounds while effectively controlling low level-stimulus properties.

  20. Pion valence-quark parton distribution function

    Directory of Open Access Journals (Sweden)

    Lei Chang

    2015-10-01

    Full Text Available Within the Dyson–Schwinger equation formulation of QCD, a rainbow ladder truncation is used to calculate the pion valence-quark distribution function (PDF. The gap equation is renormalized at a typical hadronic scale, of order 0.5 GeV, which is also set as the default initial scale for the pion PDF. We implement a corrected leading-order expression for the PDF which ensures that the valence-quarks carry all of the pion's light-front momentum at the initial scale. The scaling behavior of the pion PDF at a typical partonic scale of order 5.2 GeV is found to be (1−xν, with ν≃1.6, as x approaches one.

  1. Masked emotional priming beyond global valence activations.

    Science.gov (United States)

    Rohr, Michaela; Degner, Juliane; Wentura, Dirk

    2012-01-01

    An immense body of research demonstrates that emotional facial expressions can be processed unconsciously. However, it has been assumed that such processing takes place solely on a global valence-based level, allowing individuals to disentangle positive from negative emotions but not the specific emotion. In three studies, we investigated the specificity of emotion processing under conditions of limited awareness using a modified variant of an affective priming task. Faces with happy, angry, sad, fearful, and neutral expressions were presented as masked primes for 33 ms (Study 1) or 14 ms (Studies 2 and 3) followed by emotional target faces (Studies 1 and 2) or emotional adjectives (Study 3). Participants' task was to categorise the target emotion. In all three studies, discrimination of targets was significantly affected by the emotional primes beyond a simple positive versus negative distinction. Results indicate that specific aspects of emotions might be automatically disentangled in addition to valence, even under conditions of subjective unawareness.

  2. 5th International Conference on Valence Fluctuations

    CERN Document Server

    Malik, S

    1987-01-01

    During the Koln meeting (August 28-31, 1984), Irdia was chosen as the venue for the next International Conference on Valence Fluctuations. lhis was in recognition ard appreciation of the work done, both experimental ard theoretical, by the Irdian scientists in this area during the last decade. We decided to hold this Conference in the month of January, 1987 at Bangalore. lhe subject of Valence Fluctuations has kept itself alive ard active as it has provided many shocks ard suprises particularly among the Ce- ard U-based intermetallies. lhe richness of many interesting physical phenomena occurring in mixed valent materials, the flexibility of modifying their physical properties (by alloying, for example) ard the possibility of synthesizing a wide variety of new such materials seem to be the key factors in this regard. Barely six months before this Conference, an International Conference on Anomalous Rare Earths and Actinides (ICAREA) had been held at Grenoble (July, 1986) which also focussed on mixed valence a...

  3. Stark spectroscopy of mixed-valence systems.

    Science.gov (United States)

    Silverman, Lisa N; Kanchanawong, Pakorn; Treynor, Thomas P; Boxer, Steven G

    2008-01-13

    Many mixed-valence systems involve two or more states with different electric dipole moments whose magnitudes depend upon the charge transfer distance and the degree of delocalization; these systems can be interconverted by excitation of an intervalence charge transfer transition. Stark spectroscopy involves the interaction between the change in dipole moment of a transition and an electric field, so the Stark spectra of mixed-valence systems are expected to provide quantitative information on the degree of delocalization. In limiting cases, a classical Stark analysis can be used, but in intermediate cases the analysis is much more complex because the field affects not only the band position but also the intrinsic bandshape. Such non-classical Stark effects lead to widely different bandshapes. Several examples of both classes are discussed. Because electric fields are applied to immobilized samples, complications arise from inhomogeneous broadening, along with other effects that limit our ability to extract unique parameters in some cases. In the case of the radical cation of the special pair in photosynthetic reaction centres, where the mixed-valence system is in a very complex but structurally well-defined environment, a detailed analysis can be performed.

  4. Coordination and valence of europium in [Eu({alpha}-2-As{sub 2}W{sub 17}O{sub 61}){sub 2}]{sup 17{minus}} and [Eu(W{sub 5}O{sub 18}){sub 2}]{sup 9{minus}}

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, M.R.; Soderholm, L.; Jennings, G. [Argonne National Lab., IL (United States). Chemistry Div.; Francesconi, L.C.; Dankova, M.; Bartis, J. [City Univ. of New York, NY (United States). Chemistry Dept.

    1997-09-01

    Europium L{sub 3}-edge X-ray absorption fine structure (XAFS) spectroelectrochemistry was used to determine the valence of europium in [Eu({alpha}-2-As{sub 2}W{sub 17}O{sub 61}){sub 2}]{sup 17{minus}} and [Eu(w{sub 5}O{sub 18}){sub 2}]{sup 9{minus}}. Dilute solutions of these anions in aqueous supporting electrolytes were examined at ambient temperature and at extreme potentials. In situ XANES (X-ray absorption near edge structure) data revealed that Eu is trivalent in both [Eu({alpha}-2-As{sub 2}W{sub 17}O{sub 61}){sub 2}]{sup 17{minus}} and [Eu(W{sub 5}O{sub 18}){sub 2}]{sup 9{minus}} at rest potential. Furthermore, it was not reduced to Eu{sup 2+} by constant-potential bulk electrolysis at significantly reducing potentials under the electrochemical conditions used herein. These results stand in obvious contrast to the redox behavior of [EuP{sub 5}W{sub 30}O{sub 110}]{sup 12{minus}}, in which Eu{sup 3+} is reduced to Eu{sup 2+} under similar electrochemical conditions.

  5. Poisson Coordinates.

    Science.gov (United States)

    Li, Xian-Ying; Hu, Shi-Min

    2013-02-01

    Harmonic functions are the critical points of a Dirichlet energy functional, the linear projections of conformal maps. They play an important role in computer graphics, particularly for gradient-domain image processing and shape-preserving geometric computation. We propose Poisson coordinates, a novel transfinite interpolation scheme based on the Poisson integral formula, as a rapid way to estimate a harmonic function on a certain domain with desired boundary values. Poisson coordinates are an extension of the Mean Value coordinates (MVCs) which inherit their linear precision, smoothness, and kernel positivity. We give explicit formulas for Poisson coordinates in both continuous and 2D discrete forms. Superior to MVCs, Poisson coordinates are proved to be pseudoharmonic (i.e., they reproduce harmonic functions on n-dimensional balls). Our experimental results show that Poisson coordinates have lower Dirichlet energies than MVCs on a number of typical 2D domains (particularly convex domains). As well as presenting a formula, our approach provides useful insights for further studies on coordinates-based interpolation and fast estimation of harmonic functions.

  6. Solvent effect on intramolecular electron transfer rates of mixed-valence biferrocene monocation derivatives.

    Science.gov (United States)

    Masuda, Y; Shimizu, C

    2006-06-01

    Intramolecular electron transfer (ET) rates in various solvents of mixed-valence biferrocene monocation (Fe(II), Fe(III)) and the 1',1' ''-diiodo and 1',1' ''-diethyl derivatives (respectively abbreviated as BFC(+), I(2)BFC(+), and Et(2)BFC(+)) were determined by means of the spin-lattice relaxation times of the protons, taking into account the local magnetic field fluctuation caused by the electron hopping between the two ferrocene units. We also determined the ET rates of a mixed-valence diferrocenylacetylene monocation (DFA(+)) in order to examine the effect of the insertion of an acetylene bridge between the two ferrocene units. The insertion of the bridge decreased the ET rate, while the effect of substitution on the cyclopentadienyl rings on the rate was minor. The observed rates for each mixed-valence monocation in various solvents did not correlate with the reorganization energies, but we did find a significant contribution of the solvent dynamics. The observed rates were considerably higher than those expected on the basis of the Sumi-Marcus-Nalder model in which the solvents were regarded as dielectric continua. The slope of the logarithm plot of the pre-exponential factors in various solvents for each mixed-valence monocation versus the inverse of the longitudinal dielectric relaxation times of the solvents was significantly smaller than unity, and the slope for DFA(+) was larger than those for BFC(+), I(2)BFC(+), and Et(2)BFC(+). These results were ascribed to a partial contribution of the dielectric friction to the dynamics along the solvent coordinate; the extent of the contribution decreased with a reduction in the ET distance. For the dynamics along the solvent coordinate of the ET reactions in methanol, the observed rates indicated an important contribution by the minor dielectric relaxation components with faster relaxation times, rather than the major component with an extraordinarily long relaxation time.

  7. Reactive Force Fields via Explicit Valency

    Science.gov (United States)

    Kale, Seyit

    Computational simulations are invaluable in elucidating the dynamics of biological macromolecules. Unfortunately, reactions present a fundamental challenge. Calculations based on quantum mechanics can predict bond formation and rupture; however they suffer from severe length- and time-limitations. At the other extreme, classical approaches provide orders of magnitude faster simulations; however they regard chemical bonds as immutable entities. A few exceptions exist, but these are not always trivial to adopt for routine use. We bridge this gap by providing a novel, pseudo-classical approach, based on explicit valency. We unpack molecules into valence electron pairs and atomic cores. Particles bear ionic charges and interact via pairwise-only potentials. The potentials are informed of quantum effects in the short-range and obey dissociation limits in the long-range. They are trained against a small set of isolated species, including geometries and thermodynamics of small hydrides and of dimers formed by them. The resulting force field captures the essentials of reactivity, polarizability and flexibility in a simple, seamless setting. We call this model LEWIS, after the chemical theory that inspired the use of valence pairs. Following the introduction in Chapter 1, we initially focus on the properties of water. Chapter 2 considers gas phase clusters. To transition to the liquid phase, Chapter 3 describes a novel pairwise long-range compensation that performs comparably to infinite lattice summations. The approach is suited to ionic solutions in general. In Chapters 4 and 5, LEWIS is shown to correctly predict the dipolar and quadrupolar response in bulk liquid, and can accommodate proton transfers in both acid and base. Efficiency permits the study of proton defects at dilutions not accessible to experiment or quantum mechanics. Chapter 6 discusses explicit valency approaches in other hydrides, forming the basis of a reactive organic force field. Examples of simple

  8. Thermal Recombination: Beyond the Valence Quark Approximation

    CERN Document Server

    Müller, B; Bass, S A

    2005-01-01

    Quark counting rules derived from recombination models agree well with data on hadron production at intermediate transverse momenta in relativistic heavy-ion collisions. They convey a simple picture of hadrons consisting only of valence quarks. We discuss the inclusion of higher Fock states that add sea quarks and gluons to the hadron structure. We show that, when recombination occurs from a thermal medium, hadron spectra remain unaffected by the inclusion of higher Fock states. However, the quark number scaling for elliptic flow is somewhat affected. We discuss the implications for our understanding of data from the Relativistic Heavy Ion Collider.

  9. Reducing the negative valence of stressful memories through emotionally valenced, modality-specific tasks

    NARCIS (Netherlands)

    Tadmor, Avia; McNally, Richard J; Engelhard, Iris M

    2016-01-01

    BACKGROUND AND OBJECTIVES: People who perform a cognitively demanding secondary task while recalling a distressing memory often experience the memory as less emotional, vivid, or accurate during subsequent recollections. In this experiment, we tested whether the emotional valence (positive versus ne

  10. Mean bond-length variation in crystal structures: a bond-valence approach.

    Science.gov (United States)

    Bosi, Ferdinando

    2014-08-01

    The distortion theorem of the bond-valence theory predicts that the mean bond length 〈D〉 increases with increasing deviation of the individual bond lengths from their mean value according to the equation 〈D〉 = (D' + ΔD), where D' is the length found in a polyhedron having equivalent bonds and ΔD is the bond distortion. For a given atom, D' is expected to be similar from one structure to another, whereas 〈D〉 should vary as a function of ΔD. However, in several crystal structures 〈D〉 significantly varies without any relevant contribution from ΔD. In accordance with bond-valence theory, 〈D〉 variation is described here by a new equation: 〈D〉 = (DRU + ΔDtop + ΔDiso + ΔDaniso + ΔDelec), where DRU is a constant related to the type of cation and coordination environment, ΔDtop is the topological distortion related to the way the atoms are linked, ΔDiso is an isotropic effect of compression (or stretching) in the bonds produced by steric strain and represents the same increase (or decrease) in all the bond lengths in the coordination sphere, ΔDaniso is the distortion produced by compression and stretching of bonds in the same coordination sphere, ΔDelec is the distortion produced by electronic effects. If present, ΔDelec can be combined with ΔDaniso because they lead to the same kind of distortions in line with the distortion theorem. Each D-index, in the new equation, corresponds to an algebraic expression containing experimental and theoretical bond valences. On the basis of this study, the ΔD index defined in bond valence theory is a result of both the bond topology and the distortion theorem (ΔD = ΔDtop + ΔDaniso + ΔDelec), and D' is a result of the compression, or stretching, of bonds (D' = DRU + ΔDiso). The deficiencies present in the bond-valence theory in explaining mean bond-length variations can therefore be overcome, and the observed variations of 〈D〉 in crystal structures can be

  11. Structural Representation of Organometallics and Coordination Compounds and a Recommended Representation by Use of Dashed Lines

    Directory of Open Access Journals (Sweden)

    Shu-Kun Lin

    2002-12-01

    Full Text Available By using broken lines to represent coordination interactions in organometallic and other coordinated compounds, we can draw structures satisfying the valencies of the atoms present. These broken lines should be used to replace many false single covalent bonds now used to depict organometallic and coordinated compounds. Chemical drawing software should not recognize such broken lines as single covalent bonds and they should be ignored. An example of confusing and erroneous structural representation of organometallics and coordination compounds is discussed.

  12. Seniority Number in Valence Bond Theory.

    Science.gov (United States)

    Chen, Zhenhua; Zhou, Chen; Wu, Wei

    2015-09-01

    In this work, a hierarchy of valence bond (VB) methods based on the concept of seniority number, defined as the number of singly occupied orbitals in a determinant or an orbital configuration, is proposed and applied to the studies of the potential energy curves (PECs) of H8, N2, and C2 molecules. It is found that the seniority-based VB expansion converges more rapidly toward the full configuration interaction (FCI) or complete active space self-consistent field (CASSCF) limit and produces more accurate PECs with smaller nonparallelity errors than its molecular orbital (MO) theory-based analogue. Test results reveal that the nonorthogonal orbital-based VB theory provides a reverse but more efficient way to truncate the complete active Hilbert space by seniority numbers.

  13. Valency, Secondary Frequency, and Lexical Access: A Japanese Study.

    Science.gov (United States)

    Yamada, Jun; Kayamoto, Yuriko

    1998-01-01

    A study examined the effects of valency (associative value representing the number of two-kanji words containing the first-positional kanji of the word) on recognition of two-kanji words in Japanese. Frequency and valency of the first constituent kanji were significant factors for word recognition, and frequency of the first constituent kanji was…

  14. Prediction of valence and arousal from music features

    NARCIS (Netherlands)

    Den Brinker, A.C.; Van Dinther, C.H.B.A.; Skowronek, J.

    2011-01-01

    Mood is an important attribute of music and knowledge on mood can beused as a basic ingredient in music recommender and retrieval systems. Moods are assumed to be dominantly determined by two dimensions:valence and arousal. An experiment was conducted to attain data forsong-based ratings of valence

  15. Atoms in Valence Bond. Method, implementation and application

    NARCIS (Netherlands)

    Zielinski, M.L.

    2012-01-01

    The Atoms in Valence Bond (AiVB) approach is presented. The main goal was to develop a new and innovative approach, within the existing Valence Bond framework, to build and analyze the molecular VB wave function in terms of atoms and their atomic states, in a very user-friendly environment. The nece

  16. Spectroscopic and Redox Studies of Valence-Delocalized [Fe2S2]+ Centers in Thioredoxin-Like Ferredoxins

    Science.gov (United States)

    Subramanian, Sowmya; Duin, Evert C.; Fawcett, Sarah E. J.; Armstrong, Fraser A.; Meyer, Jacques; Johnson, Michael K.

    2015-01-01

    Reduced forms of the C56S and C60S variants of the thioredoxin-like Clostridium pasteurianum [Fe2S2] ferredoxin (CpFd) provide the only known examples of valence-delocalized [Fe2S2]+ clusters, which constitute a fundamental building block of all higher nuclearity Fe-S clusters. In this work, we have revisited earlier work on the CpFd variants and carried out redox and spectroscopic studies on the [Fe2S2]2+,+ centers in wild-type and equivalent variants of the highly homologous and structurally characterized Aquifex aeolicus ferredoxin 4 (AaeFd4) using EPR, UV-visible-NIR absorption, CD and variable-temperature MCD, and protein-film electrochemistry. The results indicate that the [Fe2S2]+ centers in the equivalent AaeFd4 and CpFd variants reversibly interconvert between similar valence-localized S = 1/2 and valence-delocalized S = 9/2 forms as a function of pH, with pKa values in the range 8.3-9.0, due to protonation of the coordinated serinate residue. However, freezing high-pH samples results in partial or full conversion from valence-delocalized S = 9/2 to valence-localized S = 1/2 [Fe2S2]+ clusters. MCD saturation magnetization data for valence-delocalized S = 9/2 [Fe2S2]+ centers facilitated determination of transition polarizations and thereby assignments of low-energy MCD bands associated with the Fe−Fe interaction. The assignments provide experimental assessment of the double exchange parameter, B, for valence-delocalized [Fe2S2]+ centers and demonstrate that variable-temperature MCD spectroscopy provides a means of detecting and investigating the properties of valence-delocalized S = 9/2 [Fe2S2]+ fragments in higher nuclearity Fe-S clusters. The origin of valence delocalization in thioredoxin-like ferredoxin Cys-to-Ser variants and Fe-S clusters in general is discussed in light of these results. PMID:25790339

  17. Valence and magnetic ordering in intermediate valence compounds: TmSe versus SmB(6).

    Science.gov (United States)

    Derr, J; Knebel, G; Lapertot, G; Salce, B; Méasson, M-A; Flouquet, J

    2006-02-15

    The intermediate valence systems TmSe and SmB(6) have been investigated up to 16 and 18 GPa by ac microcalorimetry with a pressure (p) tuning realized in situ at low temperature. For TmSe, the transition from an antiferromagnetic insulator for p3 GPa), T(N) is found to increase linearly with p. A similar linear p increase of T(N) is observed for the quasitrivalent compound TmS, which is at ambient pressure equivalent to TmSe at p∼7 GPa. In the case of SmB(6) long range magnetism has been detected above p∼8 GPa, i.e. at a pressure slightly higher than the pressure of the insulator to metal transition. However a homogeneous magnetic phase occurs only above 10 GPa. The magnetic and electronic properties are related to the renormalization of the 4f wavefunction either to the divalent or the trivalent configurations. As observed in SmS, long range magnetism in SmB(6) occurs already far below the pressure where a trivalent Sm(3+) state will be reached. It seems possible to describe roughly the physical properties of the intermediate valence equilibrium by assuming formulae for the Kondo lattice temperature depending on the valence configuration. Comparison is also made with the appearance of long range magnetism in cerium and ytterbium heavy fermion compounds.

  18. VALENCY AND SYNTACTICAL RELATION IN BIMANESS

    Directory of Open Access Journals (Sweden)

    Made Sri Satyawati

    2012-11-01

    Full Text Available This study presents the findings and descriptions of the replies to severalproblems that have not been completely and deeply discussed in the researchespreviously conducted on Bimanese. The problems are related to micro-linguistic factors,namely valency and syntactical relation in Bimanese. Both deductive and inductiveapproaches were applied to obtain satisfactory results. The main theory employed in thisstudy is Role and Reference Grammar Theory (RRG by Van Valin and J. Lapolla. It wasemployed to completely analyze the collected data in accordance with the problemsproposed in this research, and the inductive approach was employed to analyze the datain order to get novelties.In this study, clause structure is given the first priority to discuss, followed by thediscussion on operator, voice markers, nominalizers, and definiteness. Based on thepredicate category, the clause in Bimanese can be constructed with the constituents thatare under the categories of verb, noun, adjective, number, and adverb (prepositionalphrase. Based on the clause analysis, it has been found that in Bimanese there are severaloperators, each of which has different functional boundary in marking the clausemeaning. One operator may only sign nucleus, core (nucleus and argument, or core andperiphery. Bimanese has also been identified to have four linguistic states expressed byverbs that are made to make sense based on state (Aktisontrat, achievement, andaccomplishment. RRG classifies verbs into ten instead of four. However, in this study, tomake the analysis easier, verbs are classified into four. The predicate in Bimanese can beboth serial verbs and secondary verbs. It has also been found that the mechanism ofchange in valency is marked by the attachment of markers to the verbs resulting incausativity, applicativity, and resultivity. From those syntactical constructions, thesyntactical relation in Bimanese can be clearly identified. The discussion on syntacticalrelation

  19. A Valence-Bond Nonequilibrium Solvation Model for a Twisting Cyanine Dye

    CERN Document Server

    McConnell, Sean; Olsen, Seth

    2014-01-01

    We study a two-state valence-bond electronic Hamiltonian model of non-equilibrium solvation during the excited-state twisting reaction of monomethine cyanines. These dyes are of interest because of the strong environment-dependent enhancement of their fluorescence quantum yield that results from suppression of competing non-radiative decay via twisted internal charge-transfer (TICT) states. For monomethine cyanines, where the ground state is a superposition of structures with different bond and charge localization, there are two twisting pathways with different charge localization in the excited state. The Hamiltonian designed to be as simple as possible consistent with a few well-enumerated assumptions. It is defined by three parameters and is a function of two $\\pi$-bond twisting angle coordinates and a single solvation coordinate. For parameters corresponding to symmetric monomethines, there are two low-energy twisting channels on the excited-state surface that lead to a manifold of twisted intramolecular ...

  20. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball

    Overview From a technical perspective, CMS has been in “beam operation” state since 6th November. The detector is fully closed with all components operational and the magnetic field is normally at the nominal 3.8T. The UXC cavern is normally closed with the radiation veto set. Access to UXC is now only possible during downtimes of LHC. Such accesses must be carefully planned, documented and carried out in agreement with CMS Technical Coordination, Experimental Area Management, LHC programme coordination and the CCC. Material flow in and out of UXC is now strictly controlled. Access to USC remains possible at any time, although, for safety reasons, it is necessary to register with the shift crew in the control room before going down.It is obligatory for all material leaving UXC to pass through the underground buffer zone for RP scanning, database entry and appropriate labeling for traceability. Technical coordination (notably Stephane Bally and Christoph Schaefer), the shift crew and run ...

  1. One Way to Design a Valence-Skip Compound

    Science.gov (United States)

    Hase, I.; Yanagisawa, T.; Kawashima, K.

    2017-02-01

    Valence-skip compound is a good candidate with high T c and low anisotropy because it has a large attractive interaction at the site of valence-skip atom. However, it is not easy to synthesize such compound because of (i) the instability of the skipping valence state, (ii) the competing charge order, and (iii) that formal valence may not be true in some compounds. In the present study, we show several examples of the valence-skip compounds and discuss how we can design them by first principles calculations. Furthermore, we calculated the electronic structure of a promising candidate of valence skipping compound RbTlCl3 from first principles. We confirmed that the charge-density wave (CDW) is formed in this compound, and the Tl atoms in two crystallographic different sites take the valence Tl1+ and Tl3+. Structure optimization study reveals that this CDW is stable at the ambient pressure, while this CDW gap can be collapsed when we apply pressure with several gigapascals. In this metallic phase, we can expect a large charge fluctuation and a large electron-phonon interaction.

  2. Positron annihilation with core and valence electrons

    CERN Document Server

    Green, D G

    2015-01-01

    $\\gamma$-ray spectra for positron annihilation with the core and valence electrons of the noble gas atoms Ar, Kr and Xe is calculated within the framework of diagrammatic many-body theory. The effect of positron-atom and short-range positron-electron correlations on the annihilation process is examined in detail. Short-range correlations, which are described through non-local corrections to the vertex of the annihilation amplitude, are found to significantly enhance the spectra for annihilation on the core orbitals. For Ar, Kr and Xe, the core contributions to the annihilation rate are found to be 0.55\\%, 1.5\\% and 2.2\\% respectively, their small values reflecting the difficulty for the positron to probe distances close to the nucleus. Importantly however, the core subshells have a broad momentum distribution and markedly contribute to the annihilation spectra at Doppler energy shifts $\\gtrsim3$\\,keV, and even dominate the spectra of Kr and Xe at shifts $\\gtrsim5$\\,keV. Their inclusion brings the theoretical ...

  3. Valence Parity Renders z•-Type Ions Chemically Distinct

    OpenAIRE

    Hubler, Shane L.; Jue, April; Keith, Jason; McAlister, Graeme C.; Craciun, Gheorghe; Coon, Joshua J.

    2008-01-01

    Here we report that the odd electron z•-type ions formed by the electron-based peptide dissociation methods (electron capture or transfer, ECD or ETD) have distinctive chemical compositions from other common product ion types. Specifically, b-, c-, and y-type ions have an odd number of atoms with an odd valence (e.g., N and H), while z•-type ions contain an even number of atoms with an odd valence. This tenet, referred to as the valence parity rule, mandates that no c-type ion shall have the ...

  4. Valence bond and von Neumann entanglement entropy in Heisenberg ladders.

    Science.gov (United States)

    Kallin, Ann B; González, Iván; Hastings, Matthew B; Melko, Roger G

    2009-09-11

    We present a direct comparison of the recently proposed valence bond entanglement entropy and the von Neumann entanglement entropy on spin-1/2 Heisenberg systems using quantum Monte Carlo and density-matrix renormalization group simulations. For one-dimensional chains we show that the valence bond entropy can be either less or greater than the von Neumann entropy; hence, it cannot provide a bound on the latter. On ladder geometries, simulations with up to seven legs are sufficient to indicate that the von Neumann entropy in two dimensions obeys an area law, even though the valence bond entanglement entropy has a multiplicative logarithmic correction.

  5. Valence electron theory of graphite spheroidizing in primary crystallization

    Institute of Scientific and Technical Information of China (English)

    刘志林; 孙振国; 李志林

    1995-01-01

    Bond-length-difference (BLD) analysis results show that austenrte and cementite containing Mg, Zr. S have very different valence electron structures from Fe -C austenite and cementite. We find that this difference is the tie of absorption hypothesis, surface tension hypothesis, undercooling hypothesis in graphite spheroidizing theory. By using "the model of valence electron theory of drag-like effect" in our previous paper in crystallization theory, the spheroidizing effect of Mg and Zr and the anti-spheroidizing effect of S can be explained with the valence electron structure data of phases. Therefore, electron theory of graphite spheroidizing can be advanced.

  6. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball

    2010-01-01

    Operational Experience At the end of the first full-year running period of LHC, CMS is established as a reliable, robust and mature experiment. In particular common systems and infrastructure faults accounted for <0.6 % CMS downtime during LHC pp physics. Technical operation throughout the entire year was rather smooth, the main faults requiring UXC access being sub-detector power systems and rack-cooling turbines. All such problems were corrected during scheduled technical stops, in the shadow of tunnel access needed by the LHC, or in negotiated accesses or access extensions. Nevertheless, the number of necessary accesses to the UXC averaged more than one per week and the technical stops were inevitably packed with work packages, typically 30 being executed within a few days, placing a high load on the coordination and area management teams. It is an appropriate moment for CMS Technical Coordination to thank all those in many CERN departments and in the Collaboration, who were involved in CMS techni...

  7. Trait valence and the better-than-average effect.

    Science.gov (United States)

    Gold, Ron S; Brown, Mark G

    2011-12-01

    People tend to regard themselves as having superior personality traits compared to their average peer. To test whether this "better-than-average effect" varies with trait valence, participants (N = 154 students) rated both themselves and the average student on traits constituting either positive or negative poles of five trait dimensions. In each case, the better-than-average effect was found, but trait valence had no effect. Results were discussed in terms of Kahneman and Tversky's prospect theory.

  8. Emotional valence and the free-energy principle.

    Directory of Open Access Journals (Sweden)

    Mateus Joffily

    Full Text Available The free-energy principle has recently been proposed as a unified Bayesian account of perception, learning and action. Despite the inextricable link between emotion and cognition, emotion has not yet been formulated under this framework. A core concept that permeates many perspectives on emotion is valence, which broadly refers to the positive and negative character of emotion or some of its aspects. In the present paper, we propose a definition of emotional valence in terms of the negative rate of change of free-energy over time. If the second time-derivative of free-energy is taken into account, the dynamics of basic forms of emotion such as happiness, unhappiness, hope, fear, disappointment and relief can be explained. In this formulation, an important function of emotional valence turns out to regulate the learning rate of the causes of sensory inputs. When sensations increasingly violate the agent's expectations, valence is negative and increases the learning rate. Conversely, when sensations increasingly fulfil the agent's expectations, valence is positive and decreases the learning rate. This dynamic interaction between emotional valence and learning rate highlights the crucial role played by emotions in biological agents' adaptation to unexpected changes in their world.

  9. Emotional valence and the free-energy principle.

    Science.gov (United States)

    Joffily, Mateus; Coricelli, Giorgio

    2013-01-01

    The free-energy principle has recently been proposed as a unified Bayesian account of perception, learning and action. Despite the inextricable link between emotion and cognition, emotion has not yet been formulated under this framework. A core concept that permeates many perspectives on emotion is valence, which broadly refers to the positive and negative character of emotion or some of its aspects. In the present paper, we propose a definition of emotional valence in terms of the negative rate of change of free-energy over time. If the second time-derivative of free-energy is taken into account, the dynamics of basic forms of emotion such as happiness, unhappiness, hope, fear, disappointment and relief can be explained. In this formulation, an important function of emotional valence turns out to regulate the learning rate of the causes of sensory inputs. When sensations increasingly violate the agent's expectations, valence is negative and increases the learning rate. Conversely, when sensations increasingly fulfil the agent's expectations, valence is positive and decreases the learning rate. This dynamic interaction between emotional valence and learning rate highlights the crucial role played by emotions in biological agents' adaptation to unexpected changes in their world.

  10. On the valence fluctuation in the early actinide metals

    Energy Technology Data Exchange (ETDEWEB)

    Söderlind, P., E-mail: soderlind@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Landa, A.; Tobin, J.G.; Allen, P. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Medling, S.; Booth, C.H. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Bauer, E.D.; Cooley, J.C. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Sokaras, D.; Weng, T.-C.; Nordlund, D. [Stanford Synchrotron Radiation Lightsource, SLAC National Laboratory, Menlo Park, CA 94025 (United States)

    2016-02-15

    Highlights: • We make a connection between experimentally observed valence fluctuations and density functional theory. • We present a new model for valence fluctuations. • We present new experimental data for uranium and valence fluctuations. - Abstract: Recent X-ray measurements suggest a degree of valence fluctuation in plutonium and uranium intermetallics. We are applying a novel scheme, in conjunction with density functional theory, to predict 5f configuration fractions of states with valence fluctuations for the early actinide metals. For this purpose we perform constrained integer f-occupation calculations for the α phases of uranium, neptunium, and plutonium metals. For plutonium we also investigate the δ phase. The model predicts uranium and neptunium to be dominated by the f{sup 3} and f{sup 4} configurations, respectively, with only minor contributions from other configurations. For plutonium (both α and δ phase) the scenario is dramatically different. Here, the calculations predict a relatively even distribution between three valence configurations. The δ phase has a greater configuration fraction of f{sup 6} compared to that of the α phase. The theory is consistent with the interpretations of modern X-ray experiments and we present resonant X-ray emission spectroscopy results for α-uranium.

  11. Coordination Capacity

    CERN Document Server

    Cuff, Paul; Cover, Thomas

    2009-01-01

    We develop elements of a theory of cooperation and coordination in networks. Rather than considering a communication network as a means of distributing information, or of reconstructing random processes at remote nodes, we ask what dependence can be established among the nodes given the communication constraints. Specifically, in a network with communication rates between the nodes, we ask what is the set of all achievable joint distributions p(x1, ..., xm) of actions at the nodes on the network. Several networks are solved, including arbitrarily large cascade networks. Distributed cooperation can be the solution to many problems such as distributed games, distributed control, and establishing mutual information bounds on the influence of one part of a physical system on another.

  12. Character Disposition and Behavior Type: Influences of Valence on Preschool Children's Social Judgments

    Science.gov (United States)

    Jones, Elaine F.; Tobias, Marvin; Pauley, Danielle; Thomson, Nicole Renick; Johnson, Shawana Lewis

    2009-01-01

    The authors studied the influences of valence information on preschool children's (n = 47) moral (good or bad), liking (liked or disliked by a friend), and consequence-of-behavior (reward or punishment) judgments. The authors presented 8 scenarios describing the behavior valence, positive valence (help, share), negative valence (verbal insult,…

  13. A diabatic representation including both valence nonadiabatic interactions and spin-orbit effects for reaction dynamics.

    Science.gov (United States)

    Valero, Rosendo; Truhlar, Donald G

    2007-09-06

    A diabatic representation is convenient in the study of electronically nonadiabatic chemical reactions because the diabatic energies and couplings are smooth functions of the nuclear coordinates and the couplings are scalar quantities. A method called the fourfold way was devised in our group to generate diabatic representations for spin-free electronic states. One drawback of diabatic states computed from the spin-free Hamiltonian, called a valence diabatic representation, for systems in which spin-orbit coupling cannot be ignored is that the couplings between the states are not zero in asymptotic regions, leading to difficulties in the calculation of reaction probabilities and other properties by semiclassical dynamics methods. Here we report an extension of the fourfold way to construct diabatic representations suitable for spin-coupled systems. In this article we formulate the method for the case of even-electron systems that yield pairs of fragments with doublet spin multiplicity. For this type of system, we introduce the further simplification of calculating the triplet diabatic energies in terms of the singlet diabatic energies via Slater's rules and assuming constant ratios of Coulomb to exchange integrals. Furthermore, the valence diabatic couplings in the triplet manifold are taken equal to the singlet ones. An important feature of the method is the introduction of scaling functions, as they allow one to deal with multibond reactions without having to include high-energy diabatic states. The global transformation matrix to the new diabatic representation, called the spin-valence diabatic representation, is constructed as the product of channel-specific transformation matrices, each one taken as the product of an asymptotic transformation matrix and a scaling function that depends on ratios of the spin-orbit splitting and the valence splittings. Thus the underlying basis functions are recoupled into suitable diabatic basis functions in a manner that

  14. Dissociable effects of valence and arousal in adaptive executive control.

    Directory of Open Access Journals (Sweden)

    Christof Kuhbandner

    Full Text Available BACKGROUND: Based on introspectionist, semantic, and psychophysiological experimental frameworks, it has long been assumed that all affective states derive from two independent basic dimensions, valence and arousal. However, until now, no study has investigated whether valence and arousal are also dissociable at the level of affect-related changes in cognitive processing. METHODOLOGY/PRINCIPAL FINDINGS: We examined how changes in both valence (negative vs. positive and arousal (low vs. high influence performance in tasks requiring executive control because recent research indicates that two dissociable cognitive components are involved in the regulation of task performance: amount of current control (i.e., strength of filtering goal-irrelevant signals and control adaptation (i.e., strength of maintaining current goals over time. Using a visual pop-out distractor task, we found that control is exclusively modulated by arousal because interference by goal-irrelevant signals was largest in high arousal states, independently of valence. By contrast, control adaptation is exclusively modulated by valence because the increase in control after trials in which goal-irrelevant signals were present was largest in negative states, independent of arousal. A Monte Carlo simulation revealed that differential effects of two experimental factors on control and control adaptation can be dissociated if there is no correlation between empirical interference and conflict-driven modulation of interference, which was the case in the present data. Consequently, the observed effects of valence and arousal on adaptive executive control are indeed dissociable. CONCLUSIONS/SIGNIFICANCE: These findings indicate that affective influences on cognitive processes can be driven by independent effects of variations in valence and arousal, which may resolve several heterogeneous findings observed in previous studies on affect-cognition interactions.

  15. RUN COORDINATION

    CERN Multimedia

    C. Delaere

    2013-01-01

    Since the LHC ceased operations in February, a lot has been going on at Point 5, and Run Coordination continues to monitor closely the advance of maintenance and upgrade activities. In the last months, the Pixel detector was extracted and is now stored in the pixel lab in SX5; the beam pipe has been removed and ME1/1 removal has started. We regained access to the vactank and some work on the RBX of HB has started. Since mid-June, electricity and cooling are back in S1 and S2, allowing us to turn equipment back on, at least during the day. 24/7 shifts are not foreseen in the next weeks, and safety tours are mandatory to keep equipment on overnight, but re-commissioning activities are slowly being resumed. Given the (slight) delays accumulated in LS1, it was decided to merge the two global runs initially foreseen into a single exercise during the week of 4 November 2013. The aim of the global run is to check that we can run (parts of) CMS after several months switched off, with the new VME PCs installed, th...

  16. RUN COORDINATION

    CERN Multimedia

    Christophe Delaere

    2013-01-01

    The focus of Run Coordination during LS1 is to monitor closely the advance of maintenance and upgrade activities, to smooth interactions between subsystems and to ensure that all are ready in time to resume operations in 2015 with a fully calibrated and understood detector. After electricity and cooling were restored to all equipment, at about the time of the last CMS week, recommissioning activities were resumed for all subsystems. On 7 October, DCS shifts began 24/7 to allow subsystems to remain on to facilitate operations. That culminated with the Global Run in November (GriN), which   took place as scheduled during the week of 4 November. The GriN has been the first centrally managed operation since the beginning of LS1, and involved all subdetectors but the Pixel Tracker presently in a lab upstairs. All nights were therefore dedicated to long stable runs with as many subdetectors as possible. Among the many achievements in that week, three items may be highlighted. First, the Strip...

  17. Space-Valence Priming with Subliminal and Supraliminal Words

    Directory of Open Access Journals (Sweden)

    Ulrich eAnsorge

    2013-02-01

    Full Text Available To date it is unclear whether (1 awareness-independent non-evaluative semantic processes influence affective semantics and whether (2 awareness-independent affective semantics influence non-evaluative semantic processing. In the current study, we investigated these questions with the help of subliminal (masked primes and visible targets in a space-valence across-category congruence effect. In line with (1, we found that subliminal space prime words influenced valence classification of supraliminal target words (Experiment 1: Classifications were faster with a congruent prime (e.g., the prime ‘up’ before the target ‘happy’ than with an incongruent prime (e.g., the prime ‘up’ before the target ‘sad’. In contrast to (2, no influence of subliminal valence primes on the classification of supraliminal space targets into up- and down-words was found (Experiment 2. Control conditions showed that standard masked response-priming effects were found with both subliminal prime types, and that an across-category congruence effect was also found with supraliminal valence primes and spatial target words. The final Experiment 3 confirmed that the across-category congruence effect indeed reflected priming of target categorization of a relevant meaning category. Together, the data jointly confirmed prediction (1 that awareness-independent non-evaluative semantic priming influences valence judgments.

  18. The acoustic correlates of valence depend on emotion family.

    Science.gov (United States)

    Belyk, Michel; Brown, Steven

    2014-07-01

    The voice expresses a wide range of emotions through modulations of acoustic parameters such as frequency and amplitude. Although the acoustics of individual emotions are well understood, attempts to describe the acoustic correlates of broad emotional categories such as valence have yielded mixed results. In the present study, we analyzed the acoustics of emotional valence for different families of emotion. We divided emotional vocalizations into "motivational," "moral," and "aesthetic" families as defined by the OCC (Ortony, Clore, and Collins) model of emotion. Subjects viewed emotional scenarios and were cued to vocalize congruent exclamations in response to them, for example, "Yay!" and "Damn!". Positive valence was weakly associated with high-pitched and loud vocalizations. However, valence interacted with emotion family for both pitch and amplitude. A general acoustic code for valence does not hold across families of emotion, whereas family-specific codes provide a more accurate description of vocal emotions. These findings are consolidated into a set of "rules of expression" relating vocal dimensions to emotion dimensions.

  19. Social learning modulates the lateralization of emotional valence.

    Science.gov (United States)

    Shamay-Tsoory, Simone G; Lavidor, Michal; Aharon-Peretz, Judith

    2008-08-01

    Although neuropsychological studies of lateralization of emotion have emphasized valence (positive vs. negative) or type (basic vs. complex) dimensions, the interaction between the two dimensions has yet to be elucidated. The purpose of the current study was to test the hypothesis that recognition of basic emotions is processed preferentially by the right prefrontal cortex (PFC), whereas recognition of complex social emotions is processed preferentially by the left PFC. Experiment 1 assessed the ability of healthy controls and patients with right and left PFC lesions to recognize basic and complex emotions. Experiment 2 modeled the patient's data of Experiment 1 on healthy participants under lateralized displays of the emotional stimuli. Both experiments support the Type as well as the Valence Hypotheses. However, our findings indicate that the Valence Hypothesis holds for basic but less so for complex emotions. It is suggested that, since social learning overrules the basic preference of valence in the hemispheres, the processing of complex emotions in the hemispheres is less affected by valence.

  20. Effects of valence and divided attention on cognitive reappraisal processes.

    Science.gov (United States)

    Morris, John A; Leclerc, Christina M; Kensinger, Elizabeth A

    2014-12-01

    Numerous studies have investigated the neural substrates supporting cognitive reappraisal, identifying the importance of cognitive control processes implemented by prefrontal cortex (PFC). This study examined how valence and attention affect the processes used for cognitive reappraisal by asking participants to passively view or to cognitively reappraise positive and negative images with full or divided attention. When participants simply viewed these images, results revealed few effects of valence or attention. However, when participants engaged in reappraisal, there was a robust effect of valence, with the reappraisal of negative relative to positive images associated with more widespread activation, including within regions of medial and lateral PFC. There also was an effect of attention, with more lateral PFC recruitment when regulating with full attention and more medial PFC recruitment when regulating with divided attention. Within two regions of medial PFC and one region of ventrolateral PFC, there was an interaction between valence and attention: in these regions, divided attention reduced activity during reappraisal of positive but not negative images. Critically, participants continued to report reappraisal success even during the Divided Attention condition. These results suggest multiple routes to successful cognitive reappraisal, depending upon image valence and the availability of attentional resources.

  1. Crystal structure of a mixed-valence μ-oxide Sn12 cluster

    Directory of Open Access Journals (Sweden)

    Marina M. Kireenko

    2014-11-01

    Full Text Available The mixed-valence μ-oxide Sn12 cluster, decacarbonyltetra-μ4-oxido-hexa-μ3-oxido-tetrakis[μ-2,2′-(pyridine-2,6-diylbis(1,1-diphenylethanolato]decatin(IIditin(IVdimolybdenum(O(2 Mo—Sn toluene heptasolvate, [Mo2Sn12(C33H27NO24O10(CO10]·7C7H8, has a crystallographically imposed inversion centre. The asymmetric unit also contains three and a half toluene solvent molecules, one of which is disordered about a centre of symmetry. The complex molecule comprises six distinct Sn atom species with four different coordination numbers, namely 3, 4, 5, and 6. The SnII atoms forming the central Sn10O10 core adopt distorted trigonal–pyramidal, square-pyramidal and octahedral coordination geometries provided by the μ-oxide atoms and by the O- and N-donor atoms of two pyridinediethanolate ligands. The terminal SnIV atoms have distorted trigonal–bipyramidal coordination geometries, with a μ4-oxide atom and the N atom of a pyridinediethanolate ligand occupying the axial positions, and the Mo atom of a Mo(CO5 group and the alkoxy O atoms of a ligand forming the equatorial plane. In the crystal, weak intra- and intermolecular C—H...O hydrogen bonds are observed.

  2. Circulant Double Coverings of a Circulant Graph of Valency Five

    Institute of Scientific and Technical Information of China (English)

    Rong Quan FENG; Jin Ho KWAK

    2007-01-01

    Enumerating the isomorphism classes of several types of graph covering projections is one of the central research topics in enumerative topological graph theory. A covering of G is called circulant if its covering graph is circulant. Recently, the authors [Discrete Math., 277, 73-85 (2004)]enumerated the isomorphism classes of circulant double coverings of a certain type, called a typicalcovering, and showed that no double covering of a circulant graph of valency three is circulant. Also, in [Graphs and Combinatorics, 21, 386-400 (2005)], the isomorphism classes of circulant double coverings of a circulant graph of valency four are enumerated. In this paper, the isomorphism classes of circulant double coverings of a circulant graph of valency five are enumerated.

  3. Bond valence parameterslinearly dependent on the molybdenum oxidation states

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on the available crystal data, a linear correlation between R0, the bond valence parameter for a Mo-containing chemical bond, and the Mo oxidation state n was developed for the first time. Using the "universal" value of the parameter B = 0.037 nm, the linear equations of R0-n for Mo-X (X: O, S, N, Cl and F) bonds were established. The oxidation-state independent Mo-O bond valence parameters, R0 = 0.18788 nm and B = 0.03046 nm, published recently have been shown to be a special case of the linearly correlated functions. Some bond valence sum calculations in compounds containing only Mo-O bonds using these para- meters are presented.

  4. Conduction Mechanism of Valence Change Resistive Switching Memory: A Survey

    Directory of Open Access Journals (Sweden)

    Ee Wah Lim

    2015-09-01

    Full Text Available Resistive switching effect in transition metal oxide (TMO based material is often associated with the valence change mechanism (VCM. Typical modeling of valence change resistive switching memory consists of three closely related phenomena, i.e., conductive filament (CF geometry evolution, conduction mechanism and temperature dynamic evolution. It is widely agreed that the electrochemical reduction-oxidation (redox process and oxygen vacancies migration plays an essential role in the CF forming and rupture process. However, the conduction mechanism of resistive switching memory varies considerably depending on the material used in the dielectric layer and selection of electrodes. Among the popular observations are the Poole-Frenkel emission, Schottky emission, space-charge-limited conduction (SCLC, trap-assisted tunneling (TAT and hopping conduction. In this article, we will conduct a survey on several published valence change resistive switching memories with a particular interest in the I-V characteristic and the corresponding conduction mechanism.

  5. Recognizing the emotional valence of names: an ERP study.

    Science.gov (United States)

    Wang, Lin; Zhu, Zude; Bastiaansen, Marcel; Hagoort, Peter; Yang, Yufang

    2013-04-01

    Unlike common nouns, person names refer to unique entities and generally have a referring function. We used event-related potentials to investigate the time course of identifying the emotional meaning of nouns and names. The emotional valence of names and nouns were manipulated separately. The results show early N1 effects in response to emotional valence only for nouns. This might reflect automatic attention directed towards emotional stimuli. The absence of such an effect for names supports the notion that the emotional meaning carried by names is accessed after word recognition and person identification. In addition, both names with negative valence and emotional nouns elicited late positive effects, which have been associated with evaluation of emotional significance. This positive effect started earlier for nouns than for names, but with similar durations. Our results suggest that distinct neural systems are involved in the retrieval of names' and nouns' emotional meaning.

  6. Photoinduced mixed valency in zinc porphyrin dimer of triruthenium cluster dyads.

    Science.gov (United States)

    Henderson, Jane; Kubiak, Clifford P

    2014-10-20

    The preparation, electrochemistry, and spectroscopic characterization of three new species, (ZnTPPpy)Ru3O(OAc)6(CO)-pz-Ru3O(OAc)6(CO)L, where ZnTPPpy = zinc(II) 5-(4-pyridyl)-10,15,20-triphenylporphyin, L = pyridyl ligand, and pz = pyrazine, are reported. These porphyrin-coordinated Ru3O–BL–Ru3O (BL = bridging ligand) dyads are capable of undergoing intramolecular electron transfer from the photoexcited Zn porphyrin to Ru3O donor–bridge–acceptor dimer systems. Seven reversible redox processes are observed in the cyclic voltammograms of the newly synthesized dyads, showing no significant electrochemical interaction between the redox active porphyrin and the pyrazine-bridged ruthenium dimer of Ru3O trimers. From the electrochemical behavior of the dyads, large comproportionation constants (Kc = 6.0 × 10(7) for L = dmap) were calculated from the reduction potentials of the Ru(III)Ru(III)Ru(II) clusters, indicating a stable mixed-valence state. Electronic absorption spectra of the singly reduced mixed-valence species show two intervalence charge transfer (IVCT) bands assigned within the Brunschwig–Creutz–Sutin semiclassical three-state model as metal-to-bridge and metal-to-metal in character. The progression from most to least delocalized mixed-valence dimer ions, as determined by the divergence of the IVCT bands and in agreement with electrochemical data, follows the order of L = 4-dimethylaminopyridine (dmap) > pyridine (py) > 4-cyanopyridine (cpy). These systems show dynamic coalescence of the infrared spectra in the ν(CO) region of the singly reduced state. This sets the time scale of electron exchange at dimer is predicted to be thermodynamically favorable, with ΔGFET(0) ranging from −0.54 eV for L = dmap to −0.62 eV for L = cpy. Observation of IVCT band growth under continual photolysis (λexc = 568 nm) confirms a phototriggered intramolecular electron transfer process resulting in a strongly coupled singly reduced mixed-valence species.

  7. Lattice anomalies in CeNi unstable valence compound

    Energy Technology Data Exchange (ETDEWEB)

    Lazukov, V.N.; Nefeodova, E.V.; Alekseev, P.A.; Nemkovski, K.S.; Sadikov, I.P.; Tiden, N.N. [RRC ' ' Kurchatov Institute' ' , 123182 Moscow (Russian Federation); Sikolenko, V.V. [JINR, 141980 Dubna, Moscow region (Russian Federation); Staub, U.; Pradervand, C. [SLS, PSI, 5232 Villigen PSI (Switzerland); Braden, M. [LLB, CEA/Saclay, 91191 Gif sur Yvette Cedex (France); INFP Postfach 3640, 76021 Karlsruhe (Germany); Soderholm, L. [Chemistry Division, Argonne National Laboratory, Argonne Il-60439 (United States)

    2002-07-01

    Neutron diffraction and X-ray absorption measurements have been performed to study the changes in the structure and the Ce valence between 10 K and 295 K. No evidence for a phase transition was obtained, but some nearest-neighbour distances have clear peculiarities in the temperature range of 100 K to 150 K. The valence of Ce increases continuously with decreasing temperature, which can explain neither the lattice anomalies nor the previously observed temperature dependence of the phonon frequencies. A correlation between the gap-like magnetic excitation spectrum formed at low temperatures and observed lattice anomalies is discussed. (orig.)

  8. Motor coordination: a local hub for coordination.

    Science.gov (United States)

    Calabrese, Ronald L

    2014-03-31

    A local interneuron of a crayfish central pattern generator serves as a hub that integrates ascending and descending coordinating information and passes it on to a local oscillatory microcircuit to coordinate a series of segmental appendages known as swimmerets.

  9. A mixed-valence metallogrid [CoCo] with an unusual electronic structure and single-ion-magnet characterization.

    Science.gov (United States)

    Huang, Wei; Pan, Feifei; Wang, Zhenxing; Bai, Yan; Feng, Xuejun; Gu, Jiande; Ouyang, Zhong-Wen; Wu, Dayu

    2017-04-11

    The reaction of the multisite coordination ligand (H2L) with Co(Ac)2·4H2O in the absence of any base affords a homometallic tetranuclear mixed-valence complex, [Co4(L)4(CH3CO2)2(CH3OH)2]·Et2O (1). This mixed-valence metallogrid [Co4(L)4(CH3CO2)2 (CH3OH)2]·Et2O (1) has been theoretically and experimentally analyzed to assign the valence and spin state in the form of trans-[Co-Co-Co-Co]. HF-EPR reveals the presence of axial anisotropy (D = -34.4 cm(-1)) with a significant transverse component (E = 9.5 cm(-1)) in the local high spin cobalt centers. Slow magnetic relaxation effects were observed in the presence of a dc field, demonstrating field-induced single ion magnetic behavior, which is associated with the unusual electronic structure of Co(ii) within the metallogrid.

  10. Mobile linkers on DNA-coated colloids: valency without patches.

    Science.gov (United States)

    Angioletti-Uberti, Stefano; Varilly, Patrick; Mognetti, Bortolo M; Frenkel, Daan

    2014-09-19

    Colloids coated with single-stranded DNA (ssDNA) can bind selectively to other colloids coated with complementary ssDNA. The fact that DNA-coated colloids (DNACCs) can bind to specific partners opens the prospect of making colloidal "molecules." However, in order to design DNACC-based molecules, we must be able to control the valency of the colloids, i.e., the number of partners to which a given DNACC can bind. One obvious, but not very simple approach is to decorate the colloidal surface with patches of single-stranded DNA that selectively bind those on other colloids. Here we propose a design principle that exploits many-body effects to control the valency of otherwise isotropic colloids. Using a combination of theory and simulation, we show that we can tune the valency of colloids coated with mobile ssDNA, simply by tuning the nonspecific repulsion between the particles. Our simulations show that the resulting effective interactions lead to low-valency colloids self-assembling in peculiar open structures, very different from those observed in DNACCs with immobile DNA linkers.

  11. Valence Induction with a Head-Lexicalized PCFG

    CERN Document Server

    Carroll, G; Carroll, Glenn; Rooth, Mats

    1998-01-01

    This paper presents an experiment in learning valences (subcategorization frames) from a 50 million word text corpus, based on a lexicalized probabilistic context free grammar. Distributions are estimated using a modified EM algorithm. We evaluate the acquired lexicon both by comparison with a dictionary and by entropy measures. Results show that our model produces highly accurate frame distributions.

  12. Prévalence et abondance de Charletonia cameroonensis Haitlinger ...

    African Journals Online (AJOL)

    Mots clés: Abondance, prévalence, C. cameroonensis, Z. variegatus, Zone côtière ... Kekeunou 2014 (Acari : Erythraeidae) in the coastal area of Cameroon. ... between the parasite abundance and the size of Z. variegatus population.

  13. Resonance and Aromaticity : An Ab Initio Valence Bond Approach

    NARCIS (Netherlands)

    Rashid, Zahid; van Lenthe, Joop H.; Havenith, Remco W. A.

    2012-01-01

    Resonance energy is one of the criteria to measure aromaticity. The effect of the use of different orbital models is investigated in the calculated resonance energies of cyclic conjugated hydrocarbons within the framework of the ab initio Valence Bond Self-Consistent Field (VBSCF) method. The VB wav

  14. Spin Dynamics and Magnetic Ordering in Mixed Valence Systems

    DEFF Research Database (Denmark)

    Shapiro, S. M.; Bjerrum Møller, Hans; Axe, J. D.

    1978-01-01

    Neutron scattering measurements are reported on the mixed valence compounds Ce//1// minus //xTh//x and TmSe. The chi double prime (Q, omega ) as derived from the inelastic spectra of Ce//0//. //7//4Th//0//. //2//6 shows a peak in the gamma phase near 20. 0 meV and shifts abruptly to greater than 70...

  15. Voice and Valency in San Luis Potosi Huasteco

    Science.gov (United States)

    Munoz Ledo Yanez, Veronica

    2014-01-01

    This thesis presents an analysis of the system of transitivity, voice and valency alternations in Huasteco of San Luis Potosi (Mayan) within a functional-typological framework. The study is based on spoken discourse and elicited data collected in the municipalities of Aquismon and Tancanhuitz de Santos in the state of San Luis Potosi, Mexico. The…

  16. Raman Sideband Cooling of Two-Valence-Electron Fermionic Atoms

    Institute of Scientific and Technical Information of China (English)

    LI Guo-Hui; XU Xin-Ye

    2011-01-01

    We propose a method for laser cooling two-valence-electron fermionic atoms. Our protocol employs resolved-sideband cooling on the stimulated Raman transition between the two magnetic sublevels (m = F and m = F - 1) of the ground state with total anguiar momentum F. The optical pumping from m = F - 1 to 1 Pi are used to decouple atoms in the m = F - 1 state. We calculate the Raman coupling generated by an engineered optical lattice. The result shows that it is possible to laser cool the two-valence-electron fermionic atoms to the ground state. The atoms in the ground state provide a new system for quantum optics.%@@ We propose a method for laser cooling two-valence-electron fermionic atoms.Our protocol employs resolved- sideband cooling on the stimulated Raman transition between the two magnetic sublevels (m=F and m = F- 1) of the ground state with total angular momentum F.The optical pumping from m = F - 1 to p are used to decouple atoms in the m = F - 1 state.We calculate the Raman coupling generated by an engineered optical lattice.The result shows that it is possible to laser cool the two-valence-electron fermionic atoms to the ground state.The atoms in the ground state provide a new system for quantum optics.

  17. "Plug-and-go" strategy to manipulate streptavidin valencies.

    Science.gov (United States)

    Sun, Xun; Montiel, Daniel; Li, Hao; Yang, Haw

    2014-08-20

    The streptavidin-biotin set is one of the most widely utilized conjugation pairs in biotechnological applications. The tetravalent nature of streptavidin and its homologues, however, tends to result in such undesirable complications as cross-linking or ill-defined stoichiometry. Here, we describe a mutagenesis-free strategy to manipulate the valencies of wild-type streptavidin that only requires commercially available reagents. The basic idea is simple: one obtains the desired streptavidin valency by blocking off unwanted binding sites using ancillary biotin ("plug"); this way, the extraordinary fM-biotin-binding affinity is fully retained for the remaining sites in streptavidin. In the present implementation, the ancillary biotin is attached to an auxiliary separation handle, negatively charged DNA or His-tagged protein, via a photochemically or enzymatically cleavable linker. Mixing streptavidin with the ancillary biotin construct produces a distribution of streptavidin valencies. The subsequent chromatographic separation readily isolates the construct of desired streptavidin valency, and the auxiliary handles are easily removed afterward ("go"). We demonstrate how this "plug-and-go" strategy allows a precise control for the compositions of streptavidin-biotin conjugates at the single-molecule level. This low-entry-barrier protocol could further expand the application scope of the streptavidin technology.

  18. Contrastive Verb Valency and Conceptual Structures in the Verbal Lexicon.

    Science.gov (United States)

    Devos, Filip; And Others

    1996-01-01

    Reports on research consisting of compiling a contrastive verb valency dictionary of Dutch, French, and English whose main strength lies in depicting semantic differences between its entries and conceptual differences between languages. Using these analyses, one can start to discern nuclear and peripheral meanings, analyze possible meaning…

  19. Limitations of Radar Coordinates

    OpenAIRE

    Bini, Donato; Lusanna, Luca; Mashhoon, Bahram

    2004-01-01

    The construction of a radar coordinate system about the world line of an observer is discussed. Radar coordinates for a hyperbolic observer as well as a uniformly rotating observer are described in detail. The utility of the notion of radar distance and the admissibility of radar coordinates are investigated. Our results provide a critical assessment of the physical significance of radar coordinates.

  20. Work Valence as a Predictor of Academic Achievement in the Family Context

    Science.gov (United States)

    Porfeli, Erik; Ferrari, Lea; Nota, Laura

    2013-01-01

    This study asserts a theoretical model of academic and work socialization within the family setting. The presumed associations between parents' work valences, children's work valences and valence perceptions, and children's academic interest and achievement are tested. The results suggest that children's perceptions of parents…

  1. Developmental Reversals in False Memory: Effects of Emotional Valence and Arousal

    Science.gov (United States)

    Brainerd, C. J.; Holliday, R. E.; Reyna, V. F.; Yang, Y.; Toglia, M. P.

    2010-01-01

    Do the emotional valence and arousal of events distort children's memories? Do valence and arousal modulate counterintuitive age increases in false memory? We investigated those questions in children, adolescents, and adults using the Cornell/Cortland Emotion Lists, a word list pool that induces false memories and in which valence and arousal can…

  2. Actinide coordination sphere in various U, Np and Pu nitrato coordination complexes

    Energy Technology Data Exchange (ETDEWEB)

    Auwer, C. Den; Revel, R.; Charbonnel, M.C.; Presson, M.T. [CEA, DCC/DRRV/SEMP, Lab. de Chimie Theorique et Structurale, Bagnols sur Ceze (France); Conradson, S.D. [Los Alamos National Lab., Materials Science and Technology Div., Los Alamos, NM (United States); Simoni, E.; Du, J.F. Le [Centre Univ. Paris Sud, IPN, Orsay CEDEX (France); Madic, C. [CEA, DCC Saclay, Gif sur Yvete (France)

    1999-10-01

    Waste management of nuclear fuel represents one of the major environmental concerns of the decade. To recycle fissile valuable materials, intimate knowledge of complexation mechanisms involved in the solvent extraction processes is indispensable. Evolution of the actinide coordination sphere of AnO{sub 2}(NO{sub 3}){sub 2}TBP-type complexes (an = U, Np, Pu; TBP = tributylphosphate) with the actinide valence state have been probed by XAS at the metal L{sub III} edge. Dramatic changes in the actinide coordination sphere appeared when the An(VI) metal is reduced to An(IV). However, no significant evolution in the actinide environment has been noticed across the series UO{sub 2}{sup 2+}, NpO{sub 2}{sup 2+} and PuO{sub 2}{sup 2+}. (au)

  3. Valence, Implicated Actor, and Children's Acquiescence to False Suggestions.

    Science.gov (United States)

    Cleveland, Kyndra C; Quas, Jodi A; Lyon, Thomas D

    2016-01-01

    Although adverse effects of suggestive interviewing on children's accuracy are well documented, it remains unclear as to whether these effects vary depending on the valence of and the actor implicated in suggestions. In this study, 124 3-8-year-olds participated in a classroom activity and were later questioned about positive and negative false details. The interviewer provided positive reinforcement when children acquiesced to suggestions and negative feedback when they did not. Following reinforcement or feedback, young children were comparably suggestible for positive and negative details. With age, resistance to suggestions about negative details emerged first, followed by resistance to suggestions about positive details. Across age, more negative feedback was required to induce acquiescence to negative than positive false details. Finally, children were less willing to acquiesce when they (versus the confederate) were implicated. Findings highlight the interactive effects of valence and children's age on their eyewitness performance in suggestive contexts.

  4. Realistic estimate of valence transversity distributions from inclusive dihadron production

    CERN Document Server

    Radici, Marco; Bacchetta, Alessandro; Guagnelli, Marco

    2015-01-01

    We present an updated extraction of the transversity parton distribution based on the analysis of pion-pair production in deep-inelastic scattering off transversely polarized targets in collinear factorization. Data for proton and deuteron targets make it possible to perform a flavor separation of the valence components of the transversity distribution, using di-hadron fragmentation functions taken from the semi-inclusive production of two pion pairs in back-to-back jets in e+e- annihilation. The e+e- data from Belle have been reanalyzed using the replica method and a more realistic estimate of the uncertainties on the chiral-odd interference fragmentation function has been obtained. Then, the transversity distribution has been extracted by using the most recent and more precise COMPASS data for deep-inelastic scattering off proton targets. Our results represent the most accurate estimate of the uncertainties on the valence components of the transversity distribution currently available.

  5. Covert face recognition relies on affective valence in congenital prosopagnosia.

    Science.gov (United States)

    Bate, Sarah; Haslam, Catherine; Jansari, Ashok; Hodgson, Timothy L

    2009-06-01

    Dominant accounts of covert recognition in prosopagnosia assume subthreshold activation of face representations created prior to onset of the disorder. Yet, such accounts cannot explain covert recognition in congenital prosopagnosia, where the impairment is present from birth. Alternatively, covert recognition may rely on affective valence, yet no study has explored this possibility. The current study addressed this issue in 3 individuals with congenital prosopagnosia, using measures of the scanpath to indicate recognition. Participants were asked to memorize 30 faces paired with descriptions of aggressive, nice, or neutral behaviours. In a later recognition test, eye movements were monitored while participants discriminated studied from novel faces. Sampling was reduced for studied--nice compared to studied--aggressive faces, and performance for studied--neutral and novel faces fell between these two conditions. This pattern of findings suggests that (a) positive emotion can facilitate processing in prosopagnosia, and (b) covert recognition may rely on emotional valence rather than familiarity.

  6. Valence-band states of ion-bombarded polystyrene

    Energy Technology Data Exchange (ETDEWEB)

    Terrasi, A. (Istituto di Metodologie e Tecnologie per la Microelettronica, CNR, Corso Italia 57, 95129 Catania, Italy (IT)); Foti, G. (Dipartimento di Fisica, Universita di Catania, Corso Italia 57, 95129 Catania, (Italy)); Hwu, Y. (Synchrotron Radiation Center, University of Wisconsin-Madison, 3731 Schneider Drive, Stoughton, Wisconsin 53589-3097 (USA)); Margaritondo, G. (Ecole Polytechnique Federale de Lausanne, Department de Physique, PHB-Ecublens, CH 1015 Lausanne, (Switzerland))

    1991-08-01

    Ion-bombarded polystyrene with a 0.5-keV Ar{sup +} beam has been investigated by means of photoelectron spectroscopy performed with synchrotron radiation. After a dose of 10{sup 15} ions/cm{sup 2} the evolution of the valence band of the bombarded sample towards an amorphous carbonlike configuration is reported. From the analysis of valence-band spectra we estimated the out-diffusion of hydrogen and showed that its electronic states remain well identified and stable until the hydrogen presence is about 35% with respect to the pristine sample. Finally, comparison with mass spectroscopy measurements on deuterated polystyrene has been performed to determine hydrogen evolution during the ion irradiation.

  7. Realistic estimate of valence transversity from dihadron production

    CERN Document Server

    Radici, Marco

    2015-01-01

    We have updated our extraction of the transversity parton distribution based on the analysis of pion-pair production in deep-inelastic scattering off transversely polarized targets in collinear factorization. The most recent COMPASS data for proton and deuteron targets, complemented by previous HERMES data on the proton, make it possible to perform a flavor separation of the valence components of the transversity distribution, using di-hadron fragmentation functions taken from the semi-inclusive production of two pion pairs in back-to-back jets in $e^+ e^-$ annihilation. The $e^+ e^-$ data from BELLE have been reanalyzed to reach a more realistic estimate of the uncertainties on the chiral-odd interference fragmentation function. Our results represent the most accurate estimate of the uncertainties on the valence components of the transversity distribution currently available.

  8. Configuration of the valence neutrons of 17B

    Institute of Scientific and Technical Information of China (English)

    WANG Meng; MAO Rui-Shi; ZHANG Hong-Bin; ZHAO Tie-Cheng; XU Zhi-Guo; WANG Yue; CHEN Ruo-Fu; HUANG Tian-Heng; GAO Hui; JIA Fei; FU Fen; HU Zheng-Guo; GAO Qi; HAN Jian-Long; ZHANG Xue-Heng; ZHENG Chuan; YU Yu-Hong; FAN Rui-Rui; LI Bo; GUO Zhong-Yan; XU Hu-Shan; SUN Zhi-Yu; WANG Jian-Song; XIAO Guo-Qing; ZHAN Wen-Long; ZHANG Xue-Ying; LI Chen

    2008-01-01

    The reaction cross section of 17B on 12C target at (43.7±2.4) MeV/u has been measured at the Radioactive Ion Beam Line in Lanzhou (RIBLL). The root-mean-square matter radius (Rrms) was deduced to be (2.92±0.10) fm, while the Rrms of the core and the valence neutron distribution are 2.28 fm and 5.98 fm respectively. Assuming a "core plus 2n" structure in 17B, the mixed configuration of (2s1/2) and (1d5/2) of the valence neutrons is studied and the s-wave spectroscopic factor is found to be (80±21)%.

  9. Results from overlap valence quarks on a twisted mass sea

    CERN Document Server

    Garron, N

    2007-01-01

    We present results of lattice computations using overlap fermions on a twisted mass background. $N_f=2$ full QCD gauge configurations have been produced by the ETM Collaboration with very light pions (down to less than 300 MeV), with small lattice spacing ($a \\approx 0.09$ fm) and large volumes ($V/a^4=24^3\\times 48$). By profiting of the good chiral properties of the overlap operator for the valence quarks, it is also possible to have a precise (and unquenched) determination of those physical quantities where the chiral properties are crucial. In order to have unquenched results, we match the valence quark mass with the sea quark mass. We also perform computations with different quark masses in order to simulate (partially quenched) Strange and Charm quarks. A typical application is the computation of $B_K$, for which we present first results.

  10. Verbal pragmatics following unilateral stroke: emotional content and valence.

    Science.gov (United States)

    Borod, J C; Rorie, K D; Pick, L H; Bloom, R L; Andelman, F; Campbell, A L; Obler, L K; Tweedy, J R; Welkowitz, J; Sliwinski, M

    2000-01-01

    Verbal pragmatic aspects of discourse production were examined in 16 right brain-damaged (RBD), 16 left brain-damaged (LBD), and 16 normal control right-handed adults. The facilitation effect of emotional content, valence hypothesis, and relationship between pragmatics and emotion were evaluated. Participants produced monologues while recollecting emotional and nonemotional experiences. Transcribed monologues were rated for appropriateness on 6 pragmatic features: conciseness, lexical selection, quantity, relevancy, specificity, and topic maintenance. Overall, brain-damaged groups were rated as significantly less appropriate than normals. Consistent with the facilitation effect, emotional content enhanced pragmatic performance of LBD aphasic participants yet suppressed performance of RBD participants. Contrary to the valence hypothesis, RBD participants were more impaired for positive emotions and LBD participants for negative emotions. Pragmatic appropriateness was not strongly correlated with a measure of emotional intensity.

  11. Continuum-limit scaling of overlap fermions as valence quarks

    Energy Technology Data Exchange (ETDEWEB)

    Cichy, Krzysztof [Adam Mickiewicz Univ., Poznan (Poland). Faculty of Physics; Herdoiza, Gregorio; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC

    2009-10-15

    We present the results of a mixed action approach, employing dynamical twisted mass fermions in the sea sector and overlap valence fermions, with the aim of testing the continuum limit scaling behaviour of physical quantities, taking the pion decay constant as an example. To render the computations practical, we impose for this purpose a fixed finite volume with lattice size L{approx}1.3 fm. We also briefly review the techniques we have used to deal with overlap fermions. (orig.)

  12. Valence holes observed in nanodiamonds dispersed in water.

    Science.gov (United States)

    Petit, Tristan; Pflüger, Mika; Tolksdorf, Daniel; Xiao, Jie; Aziz, Emad F

    2015-02-21

    Colloidal dispersion is essential for most nanodiamond applications, but its influence on nanodiamond electronic properties remains unknown. Here we have probed the electronic structure of oxidized detonation nanodiamonds dispersed in water by using soft X-ray absorption and emission spectroscopies at the carbon and oxygen K edges. Upon dispersion in water, the π* transitions from sp(2)-hybridized carbon disappear, and holes in the valence band are observed.

  13. Valence parity renders z(*)-type ions chemically distinct.

    Science.gov (United States)

    Hubler, Shane L; Jue, April; Keith, Jason; McAlister, Graeme C; Craciun, Gheorghe; Coon, Joshua J

    2008-05-21

    Here we report that the odd electron z (*) -type ions formed by the electron-based peptide dissociation methods (electron capture or transfer, ECD or ETD) have distinctive chemical compositions from other common product ion types. Specifically, b-, c-, and y-type ions have an odd number of atoms with an odd valence (e.g., N and H), while z (*)-type ions contain an even number of atoms with an odd valence. This tenet, referred to as the valence parity rule, mandates that no c-type ion shall have the same chemical composition, and by extension mass, as a z (*) -type ion. By experiment we demonstrate that nearly half of all observed c- and z (*) -type product ions resulting from 226 ETD product ion spectra can be assigned to a single, correct, chemical composition and ion type by simple inspection of the m/ z peaks. The assignments provide (1) a platform to directly determine amino acid composition, (2) an input for database search algorithms, or (3) a basis for de novo sequence analysis.

  14. Nucleus-Dependent Valence-Space Approach to Nuclear Structure

    Science.gov (United States)

    Stroberg, S. R.; Calci, A.; Hergert, H.; Holt, J. D.; Bogner, S. K.; Roth, R.; Schwenk, A.

    2017-01-01

    We present a nucleus-dependent valence-space approach for calculating ground and excited states of nuclei, which generalizes the shell-model in-medium similarity renormalization group to an ensemble reference with fractionally filled orbitals. Because the ensemble is used only as a reference, and not to represent physical states, no symmetry restoration is required. This allows us to capture three-nucleon (3 N ) forces among valence nucleons with a valence-space Hamiltonian specifically targeted to each nucleus of interest. Predicted ground-state energies from carbon through nickel agree with results of other large-space ab initio methods, generally to the 1% level. In addition, we show that this new approach is required in order to obtain convergence for nuclei in the upper p and s d shells. Finally, we address the 1+/3+ inversion problem in 22Na and 46V. This approach extends the reach of ab initio nuclear structure calculations to essentially all light- and medium-mass nuclei.

  15. Sketching the pion's valence-quark generalised parton distribution

    Directory of Open Access Journals (Sweden)

    C. Mezrag

    2015-02-01

    Full Text Available In order to learn effectively from measurements of generalised parton distributions (GPDs, it is desirable to compute them using a framework that can potentially connect empirical information with basic features of the Standard Model. We sketch an approach to such computations, based upon a rainbow-ladder (RL truncation of QCD's Dyson–Schwinger equations and exemplified via the pion's valence dressed-quark GPD, Hπv(x,ξ,t. Our analysis focuses primarily on ξ=0, although we also capitalise on the symmetry-preserving nature of the RL truncation by connecting Hπv(x,ξ=±1,t with the pion's valence-quark parton distribution amplitude. We explain that the impulse-approximation used hitherto to define the pion's valence dressed-quark GPD is generally invalid owing to omission of contributions from the gluons which bind dressed-quarks into the pion. A simple correction enables us to identify a practicable improvement to the approximation for Hπv(x,0,t, expressed as the Radon transform of a single amplitude. Therewith we obtain results for Hπv(x,0,t and the associated impact-parameter dependent distribution, qπv(x,|b→⊥|, which provide a qualitatively sound picture of the pion's dressed-quark structure at a hadronic scale. We evolve the distributions to a scale ζ=2 GeV, so as to facilitate comparisons in future with results from experiment or other nonperturbative methods.

  16. The valence and spectral properties of rare-earth clusters

    CERN Document Server

    Peters, L; Litsarev, M S; Katsnelson, A Delin M I; Kirilyuk, A; Johansson, B; Sanyal, B; Eriksson, O

    2016-01-01

    The rare-earths are known to have intriguing changes of the valence, depending on chemical surrounding or geometry. Here we make predictions from theory that combines density functional theory with atomic multiplet-theory, on the transition of valence when transferring from the atomic divalent limit to the trivalent bulk, passing through different sized clusters, of selected rare-earths. We predict that Tm clusters show an abrupt change from pure divalent to pure trivalent at a size of 6 atoms, while Sm and Tb clusters are respectively pure divalent and trivalent up to 8 atoms. Larger Sm clusters are argued to likely make a transition to a mixed valent, or trivalent, configuration. The valence of all rare-earth clusters, as a function of size, is predicted from interpolation of our calculated results. We argue that the here predicted behavior is best analyzed by spectroscopic measurements, and provide theoretical spectra, based on dynamical mean field theory, in the Hubbard-I approximation, to ease experiment...

  17. Basic features of the pion valence-quark distribution function

    Directory of Open Access Journals (Sweden)

    Lei Chang

    2014-10-01

    Full Text Available The impulse-approximation expression used hitherto to define the pion's valence-quark distribution function is flawed because it omits contributions from the gluons which bind quarks into the pion. A corrected leading-order expression produces the model-independent result that quarks dressed via the rainbow–ladder truncation, or any practical analogue, carry all the pion's light-front momentum at a characteristic hadronic scale. Corrections to the leading contribution may be divided into two classes, responsible for shifting dressed-quark momentum into glue and sea-quarks. Working with available empirical information, we use an algebraic model to express the principal impact of both classes of corrections. This enables a realistic comparison with experiment that allows us to highlight the basic features of the pion's measurable valence-quark distribution, qπ(x; namely, at a characteristic hadronic scale, qπ(x∼(1−x2 for x≳0.85; and the valence-quarks carry approximately two-thirds of the pion's light-front momentum.

  18. Characterization of the valence and conduction bands in Si nanocrystals

    Science.gov (United States)

    van Buuren, T.; Terminello, L.; Chase, L.; Callcott, T.; Grush, M.

    1998-03-01

    Silicon nanocrystals with a mean diameter between 1 and 4 nm were produced by thermal evaporation of Si in Ar buffer gas and deposited on a substrate. The size-distribution and diameter of the clusters were characterized by atomic force microscopy. The valence and conduction band edges of the Si nanocrystals were measured in-situ using soft x-ray emission (SXE) and absorption (XAS) spectroscopies. The valence band of the smallest Si nanocrystals is shifted by much as 0.7 eV relative to bulk Si. Significant changes in the shape of the spectra are also observed between the Si nanocrytals and bulk Si. We interpret the shift and changes in the spectra of the valence band as resulting from an altered electronic band structure in the confined Si structures. A smaller but proportional shift of the conduction band to higher energy is also observed in the XAS spectra of the silicon nanostructures. We compare the experimentally measured bandgap to recent electronic structure calculations and find, that the experimentally measured bandgap is smaller than that predicted by theory. Work supported by the U.S. Department of Energy, BES-Materials Sciences, under Contract W-7405-ENG-48.

  19. Sketching the pion's valence-quark generalised parton distribution

    CERN Document Server

    Mezrag, C; Moutarde, H; Roberts, C D; Rodriguez-Quintero, J; Sabatie, F; Schmidt, S M

    2014-01-01

    In order to learn effectively from measurements of generalised parton distributions (GPDs), it is desirable to compute them using a framework that can potentially connect empirical information with basic features of the Standard Model. We sketch an approach to such computations, based upon a rainbow-ladder (RL) truncation of QCD's Dyson-Schwinger equations and exemplified via the pion's valence dressed-quark GPD, $H_\\pi^{\\rm v}(x,\\xi,t)$. Our analysis focuses primarily on $\\xi=0$, although we also capitalise on the symmetry-preserving nature of the RL truncation by connecting $H_\\pi^{\\rm v}(x,\\xi=\\pm 1,t)$ with the pion's valence-quark parton distribution amplitude. We explain that the impulse-approximation used hitherto to define the pion's valence dressed-quark GPD is generally invalid owing to omission of contributions from the gluons which bind dressed-quarks into the pion. A simple correction enables us to identify a practicable improvement to the approximation for $H_\\pi^{\\rm v}(x,0,t)$, expressed as th...

  20. Excitations of one-valence-proton, one-valence-neutron nucleus {sup 210}Bi from cold-neutron capture

    Energy Technology Data Exchange (ETDEWEB)

    Cieplicka-Oryńczak, N. [INFN sezione di Milano, Via Celoria 16, 20133 Milano (Italy); Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Kraków (Poland); Fornal, B.; Szpak, B. [Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Kraków (Poland); Leoni, S.; Bottoni, S. [INFN sezione di Milano, Via Celoria 16, 20133 Milano (Italy); Università degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Bazzacco, D. [Dipartimento di Fisica e Astronomia dell’Università, I-35131 Padova (Italy); INFN Sezione di Padova, I-35131 Padova (Italy); Blanc, A.; Jentschel, M.; Köster, U.; Mutti, P.; Soldner, T. [Institute Laue-Langevin, 6, rue Jules Horowitz, 38042 Grenoble Cedex 9 (France); Bocchi, G. [Università degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); France, G. de [GANIL, Bd. Becquerel, BP 55027, 14076 CAEN Cedex 05 (France); Simpson, G. [LPSC, Université Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, F-38026 Grenoble Cedex (France); Ur, C. [INFN Sezione di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); Urban, W. [Faculty of Physics, University of Warsaw, ul. Hoża 69, 02-681, Warszawa (Poland)

    2015-10-15

    The low-spin structure of one-proton, one-neutron {sup 210}Bi nucleus was investigated in cold-neutron capture reaction on {sup 209}Bi. The γ-coincidence measurements were performed with use of EXILL array consisted of 16 HPGe detectors. The experimental results were compared to shell-model calculations involving valence particles excitations. The {sup 210}Bi nucleus offers the potential to test the effective proton-neutron interactions because most of the states should arise from the proton-neutron excitations. Additionally, it was discovered that a few states should come from the couplings of valence particles to the 3{sup −} octupole vibration in {sup 208}Pb which provides also the possibility of testing the calculations involving the core excitations.

  1. On pleasure and thrill: the interplay between arousal and valence during visual word recognition.

    Science.gov (United States)

    Recio, Guillermo; Conrad, Markus; Hansen, Laura B; Jacobs, Arthur M

    2014-07-01

    We investigated the interplay between arousal and valence in the early processing of affective words. Event-related potentials (ERPs) were recorded while participants read words organized in an orthogonal design with the factors valence (positive, negative, neutral) and arousal (low, medium, high) in a lexical decision task. We observed faster reaction times for words of positive valence and for those of high arousal. Data from ERPs showed increased early posterior negativity (EPN) suggesting improved visual processing of these conditions. Valence effects appeared for medium and low arousal and were absent for high arousal. Arousal effects were obtained for neutral and negative words but were absent for positive words. These results suggest independent contributions of arousal and valence at early attentional stages of processing. Arousal effects preceded valence effects in the ERP data suggesting that arousal serves as an early alert system preparing a subsequent evaluation in terms of valence. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Movement and Coordination

    Science.gov (United States)

    ... Español Text Size Email Print Share Movement and Coordination Page Content Article Body At this age, your ... level will strengthen his body and develop his coordination. In the months ahead, your child’s running will ...

  3. Developmental coordination disorder

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001533.htm Developmental coordination disorder To use the sharing features on this page, please enable JavaScript. Developmental coordination disorder is a childhood disorder. It leads to ...

  4. Coordination and Cooperation

    OpenAIRE

    Janssen, Maarten

    2003-01-01

    textabstractThis comment makes four related points. First, explaining coordination is different from explaining cooperation. Second, solving the coordination problem is more important for the theory of games than solving the cooperation problem. Third, a version of the Principle of Coordination can be rationalized on individualistic grounds. Finally, psychological game theory should consider how players perceive their gaming situation. ---------------------------------------------------------...

  5. Processing Coordination Ambiguity

    Science.gov (United States)

    Engelhardt, Paul E.; Ferreira, Fernanda

    2010-01-01

    We examined temporarily ambiguous coordination structures such as "put the butter in the bowl and the pan on the towel." Minimal Attachment predicts that the ambiguous noun phrase "the pan" will be interpreted as a noun-phrase coordination structure because it is syntactically simpler than clausal coordination. Constraint-based theories assume…

  6. Processing Coordination Ambiguity

    Science.gov (United States)

    Engelhardt, Paul E.; Ferreira, Fernanda

    2010-01-01

    We examined temporarily ambiguous coordination structures such as "put the butter in the bowl and the pan on the towel." Minimal Attachment predicts that the ambiguous noun phrase "the pan" will be interpreted as a noun-phrase coordination structure because it is syntactically simpler than clausal coordination. Constraint-based…

  7. Coordination and Cooperation

    NARCIS (Netherlands)

    M.C.W. Janssen (Maarten)

    2003-01-01

    textabstractThis comment makes four related points. First, explaining coordination is different from explaining cooperation. Second, solving the coordination problem is more important for the theory of games than solving the cooperation problem. Third, a version of the Principle of Coordination can

  8. Coordination and Cooperation

    NARCIS (Netherlands)

    M.C.W. Janssen (Maarten)

    2003-01-01

    textabstractThis comment makes four related points. First, explaining coordination is different from explaining cooperation. Second, solving the coordination problem is more important for the theory of games than solving the cooperation problem. Third, a version of the Principle of Coordination can

  9. Valence-quark distribution functions in the kaon and pion

    Science.gov (United States)

    Chen, Chen; Chang, Lei; Roberts, Craig D.; Wan, Shaolong; Zong, Hong-Shi

    2016-04-01

    We describe expressions for pion and kaon dressed-quark distribution functions that incorporate contributions from gluons which bind quarks into these mesons and hence overcome a flaw of the commonly used handbag approximation. The distributions therewith obtained are purely valence in character, ensuring that dressed quarks carry all the meson's momentum at a characteristic hadronic scale and vanish as (1 -x )2 when Bjorken-x →1 . Comparing such distributions within the pion and kaon, it is apparent that the size of S U (3 ) -flavor symmetry breaking in meson parton distribution functions is modulated by the flavor dependence of dynamical chiral symmetry breaking. Corrections to these leading-order formulas may be divided into two classes, responsible for shifting dressed-quark momentum into glue and sea quarks. Working with available empirical information, we build an algebraic framework that is capable of expressing the principal impact of both classes of corrections. This enables a realistic comparison with experiment which allows us to identify and highlight basic features of measurable pion and kaon valence-quark distributions. We find that whereas roughly two thirds of the pion's light-front momentum is carried by valence dressed quarks at a characteristic hadronic scale; this fraction rises to 95% in the kaon; evolving distributions with these features to a scale typical of available Drell-Yan data produces a kaon-to-pion ratio of u -quark distributions that is in agreement with the single existing data set, and predicts a u -quark distribution within the pion that agrees with a modern reappraisal of π N Drell-Yan data. Precise new data are essential in order to validate this reappraisal and because a single modest-quality measurement of the kaon-to-pion ratio cannot be considered definitive.

  10. Valence-quark distribution functions in the kaon and pion

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chen; Chang, Lei; Roberts, Craig D.; Wan, Shaolong; Zong, Hong-Shi

    2016-04-18

    We describe expressions for pion and kaon dressed-quark distribution functions that incorporate contributions from gluons which bind quarks into these mesons and hence overcome a flaw of the commonly used handbag approximation. The distributions therewith obtained are purely valence in character, ensuring that dressed quarks carry all the meson’s momentum at a characteristic hadronic scale and vanish as ( 1 - x ) 2 when Bjorken- x → 1 . Comparing such distributions within the pion and kaon, it is apparent that the size of S U ( 3 ) -flavor symmetry breaking in meson parton distribution functions is modulated by the flavor dependence of dynamical chiral symmetry breaking. Corrections to these leading-order formulas may be divided into two classes, responsible for shifting dressed-quark momentum into glue and sea quarks. Working with available empirical information, we build an algebraic framework that is capable of expressing the principal impact of both classes of corrections. This enables a realistic comparison with experiment which allows us to identify and highlight basic features of measurable pion and kaon valence-quark distributions. We find that whereas roughly two thirds of the pion’s light-front momentum is carried by valence dressed quarks at a characteristic hadronic scale; this fraction rises to 95% in the kaon; evolving distributions with these features to a scale typical of available Drell-Yan data produces a kaon-to-pion ratio of u -quark distributions that is in agreement with the single existing data set, and predicts a u -quark distribution within the pion that agrees with a modern reappraisal of π N Drell-Yan data. Precise new data are essential in order to validate this reappraisal and because a single modest-quality measurement of the kaon-to-pion ratio cannot be considered definitive.

  11. 1D valence bond solids in a magnetic field

    Science.gov (United States)

    Iaizzi, Adam; Sandvik, Anders W.

    2015-09-01

    A Valence bond solid (VBS) is a nonmagnetic, long-range ordered state of a quantum spin system where local spin singlets are formed in some regular pattern. We here study the competition between VBS order and a fully polarized ferromagnetic state as function of an external magnetic field in a one-dimensional extended Heisenberg model—the J-Q2 model— using stochastic series expansion (SSE) quantum Monte Carlo simulations with directed loop updates. We discuss the ground state phase diagram.

  12. Electron Momentum Spectroscopy of Ethanethiol Complete Valence Shell

    Institute of Scientific and Technical Information of China (English)

    Xin-xia Xue; Mi Yan; Fang Wu; Xu Shan; Ke-zun Xu; Xiang-jun Chen

    2008-01-01

    The binding energy spectra and electron momentum distributions for the complete valence orbitals of ethanethiol were measured for the first time by binary (e, 2e) electron momentum spectroscopy employing non-coplanar symmetric kinematics at an impact energy of 1200 eV plus binding energy. The experimental results are generally consistent with the theoretical calculations using density functional theory and Hartree-Fock methods with various basis sets. A possible satellite line at 17.8 eV in binding energy spectrum was observed and studied by electron momentum spectroscopy.

  13. Valence-band photoemission intensities in thorium dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, W.P.; Boring, A.M.; Cox, L.E.; Cowan, R.D.; Arko, A.J. (Los Alamos National Lab., NM (USA)); Allen, J.W. (Michigan Univ., Ann Arbor, MI (USA). Dept. of Physics); Pate, B.B.; Lindau, I. (Stanford Univ., CA (USA). Synchrotron Radiation Lab.)

    1989-11-01

    Resonant photoemission spectra of the O 2p-derived valence band of insulating ThO{sub 2} are compared to linear muffin-tin orbital (LMTO) density-of-state (DOS) and XPS intensity calculations. At Th 5d core-level threshold energies (85 {le} hv {le} 120 eV), resonance is greatest at the bottom of the O 2p band where calculated p/d hybrid states are greatest; p/f hybrid content is weak by comparison. We conclude that the dominant hybridization is between O 2p states and Th 6d. (author).

  14. Crystal structures of two mixed-valence copper cyanide complexes with N-methyl-ethylenedi-amine.

    Science.gov (United States)

    Corfield, Peter W R; Sabatino, Alexander

    2017-02-01

    The crystal structures of two mixed-valence copper cyanide compounds involving N-methyl-ethylenedi-amine (meen), are described. In compound (I), poly[bis(μ3-cyanido-κ3C:C:N)tris(μ2-cyanido-κ2C:N)bis(N-methylethane-1,2-di-amine-κ2N,N')tricopper(I)copper(II)], [Cu4(CN)5(C3H10N2)2] or Cu4(CN)5meen2, cyanide groups link Cu(I) atoms into a three-dimensional network containing open channels parallel to the b axis. In the network, two tetra-hedrally bound Cu(I) atoms are bonded by the C atoms of two end-on bridging CN groups to form Cu2(CN)6 moieties with the Cu atoms in close contact at 2.560 (1) Å. Other trigonally bound Cu(I) atoms link these units together to form the network. The Cu(II) atoms, coordinated by two meen units, are covalently linked to the network via a cyanide bridge, and project into the open network channels. In the mol-ecular compound (II), [(N-methylethylenediamine-κ(2)N,N')copper(II)]-μ(2)-cyanido-κ(2)C:N-[bis(cyanido-κC)copper(I)] monohydrate, [Cu2(CN)3(C3H10N2)2]·H2O or Cu2(CN)3meen2·H2O, a CN group connects a Cu(II) atom coordinated by two meen groups with a trigonal-planar Cu(I) atom coordinated by CN groups. The mol-ecules are linked into centrosymmetric dimers via hydrogen bonds to two water mol-ecules. In both compounds, the bridging cyanide between the Cu(II) and Cu(I) atoms has the N atom bonded to Cu(II) and the C atom bonded to Cu(I), and the Cu(II) atoms are in a square-pyramidal coordination.

  15. Processing negative valence of word pairs that include a positive word.

    Science.gov (United States)

    Itkes, Oksana; Mashal, Nira

    2016-09-01

    Previous research has suggested that cognitive performance is interrupted by negative relative to neutral or positive stimuli. We examined whether negative valence affects performance at the word or phrase level. Participants performed a semantic decision task on word pairs that included either a negative or a positive target word. In Experiment 1, the valence of the target word was congruent with the overall valence conveyed by the word pair (e.g., fat kid). As expected, response times were slower in the negative condition relative to the positive condition. Experiment 2 included target words that were incongruent with the overall valence of the word pair (e.g., fat salary). Response times were longer for word pairs whose overall valence was negative relative to positive, even though these word pairs included a positive word. Our findings support the Cognitive Primacy Hypothesis, according to which emotional valence is extracted after conceptual processing is complete.

  16. Expertise in video game playing is associated with reduced valence-concordant emotional expressivity.

    Science.gov (United States)

    Weinreich, André; Strobach, Tilo; Schubert, Torsten

    2015-01-01

    In carefully selected groups of video game playing (VGP) experts and nonexperts, we examined valence-concordant emotional expressivity. We measured electromyographic (EMG) activity over the corrugator supercilii muscle while participants viewed pleasant, neutral, and unpleasant pictures. Potential group differences concerning valence-concordant expressivity may arise from differences concerning the participants' emotional reactivity. To control for such differences, we concomitantly measured skin conductance response (SCR) and, in a separate affect misattribution procedure (AMP), valence transfer from the same set of stimuli. Importantly, we found attenuated valence-concordant EMG activity over the corrugator supercilii muscle in VGP experts compared to nonexperts, but no differences were evident concerning SCR or valence transfer in the AMP. The findings suggest that expertise in VGP is particularly associated with reduced valence-concordant emotional expressivity.

  17. Virtual Distance and Soundstage, and their Impacts on Experienced Emotional Valence

    DEFF Research Database (Denmark)

    Christensen, Justin

    2015-01-01

    Research from animal ethology and affective neuroscience suggest that a listener’s perceived distance from a signal source can alter their experienced emotional valence of the music. Furthermore, appraisal theories of emotion suggest that emotionally valenced responses will diverge according...... to the type of emotion presented. For these exploratory investigations, subjects listen to selected musical excerpts on speakers in combination with a tactile transducer attached to their chair. The listening sessions are recorded on EEG supported by subject feedback responses. My hypothesis is that musical...... stimuli should cause stronger valenced responses in the nearfield than at a distance. Thus, music experienced as being negatively valenced at a distance should be more negatively valenced in nearfield, and music that is experienced as having a positive valence at a distance should be more positively...

  18. Valence holes observed in nanodiamonds dispersed in water

    Science.gov (United States)

    Petit, Tristan; Pflüger, Mika; Tolksdorf, Daniel; Xiao, Jie; Aziz, Emad F.

    2015-02-01

    Colloidal dispersion is essential for most nanodiamond applications, but its influence on nanodiamond electronic properties remains unknown. Here we have probed the electronic structure of oxidized detonation nanodiamonds dispersed in water by using soft X-ray absorption and emission spectroscopies at the carbon and oxygen K edges. Upon dispersion in water, the π* transitions from sp2-hybridized carbon disappear, and holes in the valence band are observed.Colloidal dispersion is essential for most nanodiamond applications, but its influence on nanodiamond electronic properties remains unknown. Here we have probed the electronic structure of oxidized detonation nanodiamonds dispersed in water by using soft X-ray absorption and emission spectroscopies at the carbon and oxygen K edges. Upon dispersion in water, the π* transitions from sp2-hybridized carbon disappear, and holes in the valence band are observed. Electronic supplementary information (ESI) available: Experimental methods, details on XAS/XES normalization and background correction procedures. See DOI: 10.1039/c4nr06639a

  19. Valence-bond quantum Monte Carlo algorithms defined on trees.

    Science.gov (United States)

    Deschner, Andreas; Sørensen, Erik S

    2014-09-01

    We present a class of algorithms for performing valence-bond quantum Monte Carlo of quantum spin models. Valence-bond quantum Monte Carlo is a projective T=0 Monte Carlo method based on sampling of a set of operator strings that can be viewed as forming a treelike structure. The algorithms presented here utilize the notion of a worm that moves up and down this tree and changes the associated operator string. In quite general terms, we derive a set of equations whose solutions correspond to a whole class of algorithms. As specific examples of this class of algorithms, we focus on two cases. The bouncing worm algorithm, for which updates are always accepted by allowing the worm to bounce up and down the tree, and the driven worm algorithm, where a single parameter controls how far up the tree the worm reaches before turning around. The latter algorithm involves only a single bounce where the worm turns from going up the tree to going down. The presence of the control parameter necessitates the introduction of an acceptance probability for the update.

  20. Relative Contribution of Odour Intensity and Valence to Moral Decisions.

    Science.gov (United States)

    Cecchetto, Cinzia; Rumiati, Raffaella Ida; Parma, Valentina

    2017-01-01

    Meta-analytic evidence showed that the chemical senses affect moral decisions. However, how odours impact on morality is currently unclear. Through a set of three studies, we assess whether and how odour intensity biases moral choices (Study 1a), its psychophysiological responses (Study 1b), as well as the behavioural and psychophysiological effects of odour valence on moral choices (Study 2). Study 1a suggests that the presence of an odour plays a role in shaping moral choice. Study 1b reveals that of two iso-pleasant versions of the same neutral odour, only the one presented sub-threshold (vs. supra-threshold) favours deontological moral choices, those based on the principle of not harming others even when such harm provides benefits. As expected, this odour intensity effect is tracked by skin conductance responses, whereas no difference in cardiac activity - proxy for the valence dimension - is revealed. Study 2 suggests that the same neutral odour presented sub-threshold increases deontological choices even when compared to iso-intense ambiguous odour, perceived as pleasant or unpleasant by half of the participants, respectively. Skin conductance responses, as expected, track odour pleasantness, but cardiac activity fails to do so. Results are discussed in the context of mechanisms alternative to disgust induction underlying moral choices.

  1. Ligand-hole localization in oxides with unusual valence Fe.

    Science.gov (United States)

    Chen, Wei-Tin; Saito, Takashi; Hayashi, Naoaki; Takano, Mikio; Shimakawa, Yuichi

    2012-01-01

    Unusual high-valence states of iron are stabilized in a few oxides. A-site-ordered perovskite-structure oxides contain such iron cations and exhibit distinct electronic behaviors at low temperatures, e.g. charge disproportionation (4Fe⁴⁺ → 2Fe³⁺ + 2Fe⁵⁺) in CaCu₃Fe₄O₁₂ and intersite charge transfer (3Cu²⁺ + 4Fe³·⁷⁵⁺ → 3Cu³⁺ + 4Fe³⁺) in LaCu₃Fe₄O₁₂. Here we report the synthesis of solid solutions of CaCu₃Fe₄O₁₂ and LaCu₃Fe₄O₁₂ and explain how the instabilities of their unusual valence states of iron are relieved. Although these behaviors look completely different from each other in simple ionic models, they can both be explained by the localization of ligand holes, which are produced by the strong hybridization of iron d and oxygen p orbitals in oxides. The localization behavior in the charge disproportionation of CaCu₃Fe₄O₁₂ is regarded as charge ordering of the ligand holes, and that in the intersite charge transfer of LaCu₃Fe₄O₁₂ is regarded as a Mott transition of the ligand holes.

  2. Neutron scattering studies of mixed-valence semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Mignot, J.M. [Laboratoire Leon Brillouin (LLB) - Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France); Alekseev, P.A. [Kurchatov Institute, Moscow (Russian Federation)

    1994-12-31

    Neutron scattering experiments on the mixed-valence (MV) compounds SmB{sub 6} are reported. The inelastic magnetic response of SmB{sub 6} at T = 2 K, measured on a double-isotope single crystal,displays a strongly damped peak at 35 meV corresponding to the inter multiplet transition of Sm{sup 2+}. At lower energies ( h.{omega} {approx_equal} 14 meV), a narrow magnetic excitation is observed, with remarkable scattering-vector and temperature dependences of its intensity. This novel feature is discussed in terms of recent theoretical works describing the formation of an anisotropic local bound state in semiconducting MV materials. If the average samarium valence is decreased by substituting La for Sm, a peak is found to appear at high energies. The elastic magnetic form factor of SmB{sub 6} was determined using polarised neutrons and no significant difference is observed in its Q-dependence with respect to that of pure divalent samarium. This surprising behaviour is constant with previous measurements on the gold (high-pressure) phase of SmS. The above results are compared to those already reported for other MV materials. In particular existing information for TmSe is supplemented by recent inelastic scattering measurements carried out on a large stoichiometric single crystal. (author). 44 refs., 7 figs.

  3. Relaxation and cross section effects in valence band photoemission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    McFeely, F.R.

    1976-09-01

    Various problems relating to the interpretation of valence band x-ray photoemission (XPS) spectra of solids are discussed. The experiments and calculations reported herein deal with the following questions: (1) To what extent do many-body effects manifest themselves in an XPS valence band spectrum, and thus invalidate a direct comparison between the photoemission energy distribution, I(E), and the density of states, N(E), calculated on the basis of ground-state one-electron theory. (2) The effect of the binding-energy-dependent photoemission cross section on I(E) at XPS energies. (3) In favorable cases indicated by (1) and (2) we examine the effect of the interaction of the crystal field with the apparent spin-orbit splittings of core levels observed in XPS spectra. (4) The use of tight binding band structure calculations to parameterize the electronic band structure from XPS and other data is described. (5) The use of high energy angle-resolved photoemission on oriented single crystals to gain orbital symmetry information is discussed. (6) The evolution of the shape of the photoemission energy distribution (of polycrystalline Cu) as a function of photon energy from 50 less than or equal h ..omega.. less than or equal 175 is discussed.

  4. Aggression proneness: Transdiagnostic processes involving negative valence and cognitive systems.

    Science.gov (United States)

    Verona, Edelyn; Bresin, Konrad

    2015-11-01

    Aggressive behavior is observed in persons with various mental health problems and has been studied from the perspectives of neuroscience and psychophysiology. The present research reviews some of the extant experimental literature to help clarify the interplay between domains of functioning implicated in aggression proneness. We then convey a process-oriented model that elucidates how the interplay of the Negative Valence and Cognitive System domains of NIMH's Research Domain Criteria (RDoC) helps explain aggression proneness, particularly reactive aggression. Finally, we report on a study involving event-related potential (ERP) indices of emotional and inhibitory control processing during an emotional-linguistic go/no-go task among 67 individuals with histories of violence and criminal offending (30% female, 44% African-American) who reported on their aggressive tendencies using the Buss-Perry Aggression Questionnaire. Results provide evidence that tendencies toward angry and aggressive behavior relate to reduced inhibitory control processing (no-go P3) specifically during relevant threat-word blocks, suggesting deterioration of cognitive control by acute or sustained threat sensitivity. These findings highlight the value of ERP methodologies for clarifying the interplay of Negative Valence and Cognitive System processes in aggression proneness.

  5. Coupled-cluster based basis sets for valence correlation calculations

    Science.gov (United States)

    Claudino, Daniel; Gargano, Ricardo; Bartlett, Rodney J.

    2016-03-01

    Novel basis sets are generated that target the description of valence correlation in atoms H through Ar. The new contraction coefficients are obtained according to the Atomic Natural Orbital (ANO) procedure from CCSD(T) (coupled-cluster singles and doubles with perturbative triples correction) density matrices starting from the primitive functions of Dunning et al. [J. Chem. Phys. 90, 1007 (1989); ibid. 98, 1358 (1993); ibid. 100, 2975 (1993)] (correlation consistent polarized valence X-tuple zeta, cc-pVXZ). The exponents of the primitive Gaussian functions are subject to uniform scaling in order to ensure satisfaction of the virial theorem for the corresponding atoms. These new sets, named ANO-VT-XZ (Atomic Natural Orbital Virial Theorem X-tuple Zeta), have the same number of contracted functions as their cc-pVXZ counterparts in each subshell. The performance of these basis sets is assessed by the evaluation of the contraction errors in four distinct computations: correlation energies in atoms, probing the density in different regions of space via (-3 ≤ n ≤ 3) in atoms, correlation energies in diatomic molecules, and the quality of fitting potential energy curves as measured by spectroscopic constants. All energy calculations with ANO-VT-QZ have contraction errors within "chemical accuracy" of 1 kcal/mol, which is not true for cc-pVQZ, suggesting some improvement compared to the correlation consistent series of Dunning and co-workers.

  6. Emotional valence contributes to music-induced analgesia.

    Science.gov (United States)

    Roy, Mathieu; Peretz, Isabelle; Rainville, Pierre

    2008-01-01

    The capacity of music to soothe pain has been used in many traditional forms of medicine. Yet, the mechanisms underlying these effects have not been demonstrated. Here, we examine the possibility that the modulatory effect of music on pain is mediated by the valence (pleasant-unpleasant dimension) of the emotions induced. We report the effects of listening to pleasant and unpleasant music on thermal pain in healthy human volunteers. Eighteen participants evaluated the warmth or pain induced by 40.0, 45.5, 47.0 and 48.5 degrees C thermal stimulations applied to the skin of their forearm while listening to pleasant and unpleasant musical excerpts matched for their high level of arousal (relaxing-stimulating dimension). Compared to a silent control condition, only the pleasant excerpts produced highly significant reductions in both pain intensity and unpleasantness, demonstrating the effect of positive emotions induced by music on pain (Pairwise contrasts with silence: p'smusic condition further indicated that pain decreased significantly (p'smusic pleasantness. In contrast, the unpleasant excerpts did not modulate pain significantly, and warmth perception was not affected by the presence of pleasant or unpleasant music. Those results support the hypothesis that positive emotional valence contributes to music-induced analgesia. These findings call for the integration of music to current methods of pain control.

  7. +2 Valence Metal Concentrations in Lion Creek, Oakland, California

    Science.gov (United States)

    Vazquez, P.; Zedd, T.; Chagolla, R.; Dutton-Starbuck, M.; Negrete, A.; Jinham, M.; Lapota, M.

    2012-12-01

    Seven major creeks exist within the City of Oakland, California. These creeks all flow in the southwest direction from forested hills down through densely populated streets where they become susceptible to urban runoff. Lion Creek has been diverted to engineered channels and underground culverts and runs directly under our school (Roots International) before flowing into the San Leandro Bay. One branch of the creek begins near an abandoned sulfur mine. Previous studies have shown that extremely high levels of lead, arsenic and iron exist in this portion of the creek due to acid mine drainage. In this study +2 valence heavy metals concentration data was obtained from samples collected from a segment of the creek located approximately 2.8 miles downstream from the mine. Concentrations in samples collected at three different sites along this segment ranged between 50 ppb and 100 ppb. We hypothesize that these levels are related to the high concentration of +2 valence heavy metals at the mining site. To test this hypothesis, we have obtained samples from various locations along the roughly 3.75 miles of Lion Creek that are used to assess changes in heavy metals concentration levels from the mining site to the San Leandro Bay.

  8. In-Medium Pion Valence Distributions in a Light-Front Model

    CERN Document Server

    de Melo, J P B C; Ahmed, I

    2016-01-01

    Pion valence distributions in nuclear medium and vacuum are studied in a light-front constituent quark model. The in-medium input for studying the pion properties is calculated by the quark-meson coupling model. We find that the in-medium pion valence distribution, as well as the in-medium pion valence wave function, are substantially modified at normal nuclear matter density, due to the reduction in the pion decay constant.

  9. The Role of Fermi Resonance in Formation of Valence Band of Water Raman Scattering

    Directory of Open Access Journals (Sweden)

    Sergey A. Burikov

    2008-01-01

    Full Text Available The role of Fermi resonance in formation of valence band of water Raman scattering was investigated. Simultaneous measurement of characteristics of bending and valence bands of water in D2O solutions, KBr, and KCl and using genetic algorithms in conjunction with variation methods allowed increasing accuracy of estimation of Fermi resonance coupling constant and of Fermi resonance contribution into formation of water Raman valence band.

  10. Enhanced time overcurrent coordination

    Energy Technology Data Exchange (ETDEWEB)

    Enriquez, Arturo Conde; Martinez, Ernesto Vazquez [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, Apdo. Postal 114-F, Ciudad Universitaria, CP 66450 San Nicolas de los Garza, Nuevo Leon (Mexico)

    2006-04-15

    In this paper, we recommend a new coordination system for time overcurrent relays. The purpose of the coordination process is to find a time element function that allows it to operate using a constant back-up time delay, for any fault current. In this article, we describe the implementation and coordination results of time overcurrent relays, fuses and reclosers. Experiments were carried out in a laboratory test situation using signals of a power electrical system physics simulator. (author)

  11. A THIOLATO-BRIDGED OCTANUCLEAR COPPER(I,II MIXED- VALENCE COMPLEX WITH N,N,S-TRIDENTATE LIGAND

    Directory of Open Access Journals (Sweden)

    Takanori Kotera

    2007-06-01

    Full Text Available Thiolato-bridged complex [CuI4CuII4(peampt4Cl8]·2H2O (Hpeampt = 1-(2-pyridylethylamino methylpropane-2-thiol has been synthesized and characterized by the elemental analysis, IR and UV-vis spectroscopies and magnetic susceptibility measurement. The X-ray crystal structure analysis of this complex shows a localized mixed-valence octanuclear cage structure made up of four trigonal-bipyramidal CuIIN2SCl2, two trigonal CuIS2Cl, and two tetrahedral CuIS2Cl2 coordination sites. Temperature dependence of magnetic susceptibility (4.5— 300 K shows that a fairly strong antiferromagnetic interaction is operating between the four CuII ions.

  12. Color tuning of Eu-Tb co-doped borophosphate glasses for white light through valence state adjustment

    Institute of Scientific and Technical Information of China (English)

    XU Suo-cheng; ZHENG Xi; TIAN Hua; LV Tian-shuai; WANG Peng; WANG Da-jian

    2011-01-01

    The dependence of color points of white light on the composition of borophosphate glasses co-doped with europium (Eu) and terbium (Tb) has been investigated in terms of valence change of rare earth ions.Under ultraviolet (UV) excitation,the white light is observed to be from a combination of 4f65d → 4f7band transition emission at 425 nm for Eu2+,5D0 → 7FJ (J=-l,2) lineemissions at 593 nm and 611 nm for Eu3+,and 5D4 → 7F5 band transition emission at 545 nm for Tb3+.By varying the glass composition,the resultant emission color can be tuned efficiently.Eventually,the optimized white light with commission intemational de l'Eclairage (CIE) coordinate of (0.3382,0.2763) and the correlate color temperature (CCT) at 5010 K are achieved.

  13. Photodissociation of carbon dioxide in singlet valence electronic states. II. Five state absorption spectrum and vibronic assignment

    CERN Document Server

    Grebenshchikov, Sergy Yu

    2013-01-01

    The absorption spectrum of CO$_2$ in the wavelength range 120\\,nm --- 160\\,nm is analyzed by means of quantum mechanical calculations performed using vibronically coupled PESs of five singlet valence electronic states and the coordinate dependent transition dipole moment vectors. The thermally averaged spectrum, calculated for T=190\\,K via Boltzmann averaging of optical transitions from many initial rotational states, accurtely reproduces the experimental spectral envelope, consisting of a low and a high energy band, the positions of the absorption maxima, their FWHMs, peak intensities, and frequencies of diffuse structures in each band. Contributions of the vibronic interactions due to Renner-Teller coupling, conical intersections, and the Herzberg-Teller effect are isolated and the calculated bands are assigned in terms of adiabatic electronic states. Finally, diffuse structures in the calculated bands are vibronically assigned using wave functions of the underlying resonance states. It is demonstrated that...

  14. Role of many body shake-up in core-valence-valence electron emission from single wall carbon nanotubes.

    Science.gov (United States)

    Sindona, A; Pisarra, M; Maletta, S; Commisso, M; Riccardi, P; Bonanno, A; Barone, P; Falcone, G

    2011-10-01

    Auger core-valence-valence transitions from single wall Carbon nanotubes are studied using a tight-binding calculational scheme with nearest neighbor overlap, hopping interactions, and a double-zeta basis set. The resulting Hamiltonian approximates the unperturbed pi and sigma bands of the nanomaterials coupled with the free electron states outside the solid and the core-hole. As a first step, the Fermi's golden rule is applied to determine the so called one-electron spectrum of emitted electrons from different tubes, in which either the neutralizing or the ejected electrons, in the initial state, lie within nearest neighboring atomic sites to the core-hole. Many-body corrections are effectively modeled using a broadening function, which accounts for dynamic screening effects involving the initial and final states. Particular attention is paid to the asymmetric component of the broadening function, responsible for the shake-up of pi electrons. Finally, the Cini-Sawatzky distortion function is used to describe the final state effect of the hole-hole interaction. A quantitative estimation of the interplay of shake-up processes is proposed by adjusting the asymmetric parameters of the broadening function to reproduce measurements of Auger electrons ejected from bundles of single wall Carbon nanotubes.

  15. Valence-to-core-detected X-ray absorption spectroscopy

    DEFF Research Database (Denmark)

    Hall, Eleanor R.; Pollock, Christopher J.; Bendix, Jesper

    2014-01-01

    X-ray absorption spectroscopy (XAS) can provide detailed insight into the electronic and geometric structures of transition-metal active sites in metalloproteins and chemical catalysts. However, standard XAS spectra inherently represent an average contribution from the entire coordination...

  16. Characterizing traits of coordination

    NARCIS (Netherlands)

    Poss, R.

    2013-01-01

    How can one recognize coordination languages and technologies? As this report shows, the common approach that contrasts coordination with computation is intellectually unsound: depending on the selected understanding of the word "computation", it either captures too many or too few programming

  17. Coordination models and languages

    NARCIS (Netherlands)

    Papadopoulos, G.A.; Arbab, F.

    1998-01-01

    A new class of models, formalisms and mechanisms has recently evolved for describing concurrent and distributed computations based on the concept of ``coordination''. The purpose of a coordination model and associated language is to provide a means of integrating a number of possibly heterogeneous c

  18. Team coordination dynamics.

    Science.gov (United States)

    Gorman, Jamie C; Amazeen, Polemnia G; Cooke, Nancy J

    2010-07-01

    Team coordination consists of both the dynamics of team member interaction and the environmental dynamics to which a team is subjected. Focusing on dynamics, an approach is developed that contrasts with traditional aggregate-static concepts of team coordination as characterized by the shared mental model approach. A team coordination order parameter was developed to capture momentary fluctuations in coordination. Team coordination was observed in three-person uninhabited air vehicle teams across two experimental sessions. The dynamics of the order parameter were observed under changes of a team familiarity control parameter. Team members returned for the second session to either the same (Intact) or different (Mixed) team. 'Roadblock' perturbations, or novel changes in the task environment, were introduced in order to probe the stability of team coordination. Nonlinear dynamic methods revealed differences that a traditional approach did not: Intact and Mixed team coordination dynamics looked very different; Mixed teams were more stable than Intact teams and explored the space of solutions without the need for correction. Stability was positively correlated with the number of roadblock perturbations that were overcome successfully. The novel and non-intuitive contribution of a dynamical analysis was that Mixed teams, who did not have a long history working together, were more adaptive. Team coordination dynamics carries new implications for traditional problems such as training adaptive teams.

  19. Coordinate measuring machines

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceability...

  20. Social Postural Coordination

    Science.gov (United States)

    Varlet, Manuel; Marin, Ludovic; Lagarde, Julien; Bardy, Benoit G.

    2011-01-01

    The goal of the current study was to investigate whether a visual coupling between two people can produce spontaneous interpersonal postural coordination and change their intrapersonal postural coordination involved in the control of stance. We examined the front-to-back head displacements of participants and the angular motion of their hip and…

  1. Social Postural Coordination

    Science.gov (United States)

    Varlet, Manuel; Marin, Ludovic; Lagarde, Julien; Bardy, Benoit G.

    2011-01-01

    The goal of the current study was to investigate whether a visual coupling between two people can produce spontaneous interpersonal postural coordination and change their intrapersonal postural coordination involved in the control of stance. We examined the front-to-back head displacements of participants and the angular motion of their hip and…

  2. Resonating Valence Bond states for low dimensional S=1 antiferromagnets

    Science.gov (United States)

    Liu, Zheng-Xin; Zhou, Yi; Ng, Tai-Kai

    2014-03-01

    We study S = 1 spin liquid states in low dimensions. We show that the resonating-valence-bond (RVB) picture of S = 1 / 2 spin liquid state can be generalized to S = 1 case. For S = 1 system, a many-body singlet (with even site number) can be decomposed into superposition of products of two-body singlets. In other words, the product states of two-body singlets, called the singlet pair states (SPSs), are over complete to span the Hilbert space of many-body singlets. Furthermore, we generalized fermionic representation and the corresponding mean field theory and Gutzwiller projected stats to S = 1 models. We applied our theory to study 1D anti-ferromagnetic bilinear-biquadratic model and show that both the ground states (including the phase transition point) and the excited states can be understood excellently well within the framework. Our method can be applied to 2D S = 1 antiferromagnets.

  3. Electric Crosstalk Effect in Valence Change Resistive Random Access Memory

    Science.gov (United States)

    Sun, Jing; Wang, Hong; Wu, Shiwei; Song, Fang; Wang, Zhan; Gao, Haixia; Ma, Xiaohua

    2017-08-01

    Electric crosstalk phenomenon in valence change resistive switching memory (VCM) is systematically investigated. When a voltage is applied on the VCM device, an electric field is formed in the isolated region between the devices, which causes the oxygen vacancies in conductive filaments (CFs) to drift apart, leading to a consequent resistance degradation of the neighboring devices. The effects of distance between memory cells, electrodes widths and physical dimensions of CFs on the memory performance are investigated in this work. Furthermore, the strategies to mitigate electric crosstalk effects are developed. According to the simulation results, the crosstalk phenomenon can become more severe as the distance between memory cells or the electrode width decreases. In order to optimize the device performance, it is helpful to control the location of the break points of CFs in the device close to the top electrode. Alternatively, taking the integration density into account, switching materials with a small field accelerated parameter can also contribute to obtaining a stable performance.

  4. Plaquette valence bond theory of high-temperature superconductivity

    Science.gov (United States)

    Harland, Malte; Katsnelson, Mikhail I.; Lichtenstein, Alexander I.

    2016-09-01

    We present a strong-coupling approach to the theory of high-temperature superconductivity based on the observation of a quantum critical point in the plaquette within the t ,t' Hubbard model. The crossing of ground-state energies in the N =2 -4 sectors occurs for parameters close to the optimal doping. The theory predicts the maximum of the dx2-y2-wave order parameter at the border between localized and itinerant electron behaviors and gives a natural explanation for the pseudogap formation via the soft-fermion mode related to local singlet states of the plaquette in the environment. Our approach follows the general line of resonating valence-bond theory stressing a crucial role of singlets in the physics of high-Tc superconductors but focuses on the formation of local singlets, similar to phenomena observed in frustrated one-dimensional quantum spin models.

  5. Valence framing of political preferences and resistance to persuasion

    Directory of Open Access Journals (Sweden)

    Žeželj Iris

    2007-01-01

    Full Text Available This study tested the "valence framing effect": an assumption that negatively conceptualized attitudes (as opposing the non-preferred alternative are more resistant to later persuasion attempts. In the experiment we created choice between two political candidates and experimental subjects were led to conceptualize their political preferences in one of two possible ways: either as supporting the preferred candidate or as opposing the non-preferred candidate. The data indicate that negative preferences show less overall change when exposed to counterarguments. This finding can be incorporated in two theoretical frameworks: dual process theories of attitude change (Elaboration likelihood model and descriptive decision making theories (Prospect theory. Results are discussed for their implications for the efficacy of political communication. .

  6. Valence-quark distribution functions in the kaon and pion

    CERN Document Server

    Chen, Chen; Roberts, Craig D; Wan, Shaolong; Zong, Hong-Shi

    2016-01-01

    We describe expressions for pion and kaon dressed-quark distribution functions that incorporate contributions from gluons which bind quarks into these mesons and hence overcome a flaw of the commonly used handbag approximation. The distributions therewith obtained are purely valence in character, ensuring that dressed-quarks carry all a meson's momentum at a characteristic hadronic scale and vanishing as $(1-x)^2$ when Bjorken-$x\\to 1$. Comparing such distributions within the pion and kaon, it is apparent that the size of SU(3)-flavour symmetry breaking in meson parton distribution functions is modulated by the flavour dependence of dynamical chiral symmetry breaking. Corrections to these leading-order formulae may be divided into two classes, responsible for shifting dressed-quark momentum into glue and sea-quarks. Working with available empirical information, we build an algebraic framework that is capable of expressing the principal impact of both classes of corrections. This enables a realistic comparison...

  7. Adsorption mechanism and valency of catechol-functionalized hyperbranched polyglycerols

    Directory of Open Access Journals (Sweden)

    Stefanie Krysiak

    2015-05-01

    Full Text Available Nature often serves as a model system for developing new adhesives. In aqueous environments, mussel-inspired adhesives are promising candidates. Understanding the mechanism of the extraordinarily strong adhesive bonds of the catechol group will likely aid in the development of adhesives. With this aim, we study the adhesion of catechol-based adhesives to metal oxides on the molecular level using atomic force microscopy (AFM. The comparison of single catechols (dopamine with multiple catechols on hyperbranched polyglycerols (hPG at various pH and dwell times allowed us to further increase our understanding. In particular, we were able to elucidate how to achieve strong bonds of different valency. It was concluded that hyperbranched polyglycerols with added catechol end groups are promising candidates for durable surface coatings.

  8. Adsorption mechanism and valency of catechol-functionalized hyperbranched polyglycerols.

    Science.gov (United States)

    Krysiak, Stefanie; Wei, Qiang; Rischka, Klaus; Hartwig, Andreas; Haag, Rainer; Hugel, Thorsten

    2015-01-01

    Nature often serves as a model system for developing new adhesives. In aqueous environments, mussel-inspired adhesives are promising candidates. Understanding the mechanism of the extraordinarily strong adhesive bonds of the catechol group will likely aid in the development of adhesives. With this aim, we study the adhesion of catechol-based adhesives to metal oxides on the molecular level using atomic force microscopy (AFM). The comparison of single catechols (dopamine) with multiple catechols on hyperbranched polyglycerols (hPG) at various pH and dwell times allowed us to further increase our understanding. In particular, we were able to elucidate how to achieve strong bonds of different valency. It was concluded that hyperbranched polyglycerols with added catechol end groups are promising candidates for durable surface coatings.

  9. Paired-permanent approach to valence bond theory

    Institute of Scientific and Technical Information of China (English)

    吴玮; 吴安安; 莫亦荣; 张乾二

    1996-01-01

    A new function called paired-permanent is defined and widely discussed, and a practicable procedure for evaluations of paired-permanents is proposed, which is similar to the Laplace method for determinants. Using the concept of paired-permanents, an efficient algorithm is presented for evaluating the Hamiltonian and overlap matrix elements in the spin-free form of valence bond (VB) theory. With the new algorithm, a spin-free wavefunction is simply written as a paired-permanent, and an overlap matrix element may be obtained by evaluating a corresponding paired-permanent. Meanwhile, the Hamiltonian matrix element is expressed in terms of the summation of the products of electronic integrals and the corresponding sub-paired-permanents

  10. Nature of the Frequency Shift of Hydrogen Valence Vibrations

    CERN Document Server

    Zhyganiuk, I V

    2015-01-01

    The physical nature of a frequency shift of hydrogen valence vibrations in a water molecule due to its interaction with neighbor molecules has been studied. Electrostatic forces connected with the multipole moments of molecules are supposed to give a dominating contribution to the intermolecular interaction. The frequency shift was calculated in the case where two neighbor molecules form a dimer. The obtained result is in qualitative agreement with the frequency shifts observed for water vapor, hexagonal ice, and liquid water, as well as for aqueous solutions of alcohols. This fact testifies to the electrostatic nature of H-bonds used to describe both the specific features of the intermolecular interaction in water and the macroscopic properties of the latter.

  11. Valence electronic structure of tantalum carbide and nitride

    Institute of Scientific and Technical Information of China (English)

    FAN; ChangZeng

    2007-01-01

    The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent, metallic and ionic characters. For a quantitative analysis of the relative strength of these components, their ionicities have been calculated by implanting the results of EET to the PVL model. It has been found that the ionicity of tantalum carbide is smaller than that of tantalum nitride. The EET results also reveal that the covalent electronic number of the strongest bond in the former is larger than that of the latter. All these suggest that the covalent bond of TaC is stronger than that of TaN, which coincides to that deduced from the first-principles method.……

  12. Valence electronic structure of tantalum carbide and nitride

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent, metallic and ionic characters. For a quantitative analysis of the relative strength of these components, their ionicities have been calculated by implanting the results of EET to the PVL model. It has been found that the ionicity of tantalum carbide is smaller than that of tantalum nitride. The EET results also reveal that the covalent electronic number of the strongest bond in the former is larger than that of the latter. All these suggest that the covalent bond of TaC is stronger than that of TaN, which coincides to that deduced from the first-principles method.

  13. Kaon semileptonic decay form factors with HISQ valence quarks

    CERN Document Server

    Gamiz, E; Bazavov, A; Bernard, C; Bouchard, C; DeTar, C; Du, D; El-Khadra, A X; Foley, J; Freeland, E D; Gottlieb, Steven; Heller, U M; Kim, J; Kronfeld, A S; Laiho, J; Levkova, L; Mackenzie, P B; Neil, E T; Oktay, M B; Qiu, Si-Wei; Simone, J N; Sugar, R; Toussaint, D; Van de Water, R S; Zhou, R

    2012-01-01

    We report on the status of our kaon semileptonic form factor calculations using the highly-improved staggered quark (HISQ) formulation to simulate the valence fermions. We present results for the form factor f_+^{K \\pi}(0) on the asqtad N_f=2+1 MILC configurations, discuss the chiral-continuum extrapolation, and give a preliminary estimate of the total error. We also present a more preliminary set of results for the same form factor but with the sea quarks also simulated with the HISQ action; these results include data at the physical light quark masses. The improvements that we expect to achieve with the use of the HISQ configurations and simulations at the physical quark masses are briefly discussed.

  14. Quantum electrodynamic corrections for valence electrons in Eka-Hg

    Science.gov (United States)

    Golovko, O. A.; Goidenko, I. A.; Tupitsyn, I. I.

    2008-05-01

    The quantum electrodynamic (QED) corrections to the coupling energy of valence electrons in heavy and superheavy nuclei are calculated in the effective local-potential approximation, as well as by the Hartree-Fock-Dirac self-consistent method. It is clearly shown that the contribution from the QED corrections is within the accuracy of modern calculations, which do not take into account QED effects. It is shown that, in certain cases, to exactly calculate the coupling energy of electrons in heavy and superheavy atoms, it is necessary to take into account the self-consistency, which shows that the inaccuracy of the use of the method of the effective local potential in calculations of QED effects can exceed 10%, which is also within the limits of calculations of the coupling energy without taking into account QED effects.

  15. Dynamically Tracking Anxious Individuals' Affective Response to Valenced Information.

    Science.gov (United States)

    Fua, Karl C; Teachman, Bethany A

    2017-03-30

    Past research has shown that an individual's feelings at any given moment reflect currently experienced stimuli as well as internal representations of similar past experiences. However, anxious individuals' affective reactions to streams of interrelated valenced information (vs. reactions to static stimuli that are arguably less ecologically valid) are rarely tracked. The present study provided a first examination of the newly developed Tracking Affect Ratings Over Time (TAROT) task to continuously assess anxious individuals' affective reactions to streams of information that systematically change valence. Undergraduate participants (N = 141) completed the TAROT task in which they listened to narratives containing positive, negative, and neutral physically- or socially-relevant events, and indicated how positive or negative they felt about the information they heard as each narrative unfolded. The present study provided preliminary evidence for the validity and reliability of the task. Within scenarios, participants higher (vs. lower) in anxiety showed many expected negative biases, reporting more negative mean ratings and overall summary ratings, changing their pattern of responding more quickly to negative events, and responding more negatively to neutral events. Furthermore, individuals higher (vs. lower) in anxiety tended to report more negative minimums during and after positive events, and less positive maximums after negative events. Together, findings indicate that positive events were less impactful for anxious individuals, whereas negative experiences had a particularly lasting impact on future affective responses. The TAROT task is able to efficiently capture a number of different cognitive biases, and may help clarify the mechanisms that underlie anxious individuals' biased negative processing. (PsycINFO Database Record

  16. Entropically patchy particles: engineering valence through shape entropy.

    Science.gov (United States)

    van Anders, Greg; Ahmed, N Khalid; Smith, Ross; Engel, Michael; Glotzer, Sharon C

    2014-01-28

    Patchy particles are a popular paradigm for the design and synthesis of nanoparticles and colloids for self-assembly. In "traditional" patchy particles, anisotropic interactions arising from patterned coatings, functionalized molecules, DNA, and other enthalpic means create the possibility for directional binding of particles into higher-ordered structures. Although the anisotropic geometry of nonspherical particles contributes to the interaction patchiness through van der Waals, electrostatic, and other interactions, how particle shape contributes entropically to self-assembly is only now beginning to be understood. The directional nature of entropic forces has recently been elucidated. A recently proposed theoretical framework that defines and quantifies directional entropic forces demonstrates the anisotropic-that is, patchy-nature of these emergent, attractive forces. Here we introduce the notion of entropically patchy particles as the entropic counterpart to enthalpically patchy particles. Using three example "families" of shapes, we show how to modify entropic patchiness by introducing geometric features to the particles via shape operations so as to target specific crystal structures assembled here with Monte Carlo simulations. We quantify the emergent entropic valence via a potential of mean force and torque. We show that these forces are on the order of a few kBT at intermediate densities below the onset of crystallization. We generalize these shape operations to shape anisotropy dimensions, in analogy with the anisotropy dimensions introduced for enthalpically patchy particles. Our findings demonstrate that entropic patchiness and emergent valence provide a way of engineering directional bonding into nanoparticle systems, whether in the presence or absence of additional, non-entropic forces.

  17. Resonance and aromaticity: an ab initio valence bond approach.

    Science.gov (United States)

    Rashid, Zahid; van Lenthe, Joop H; Havenith, Remco W A

    2012-05-17

    Resonance energy is one of the criteria to measure aromaticity. The effect of the use of different orbital models is investigated in the calculated resonance energies of cyclic conjugated hydrocarbons within the framework of the ab initio Valence Bond Self-Consistent Field (VBSCF) method. The VB wave function for each system was constructed using a linear combination of the VB structures (spin functions), which closely resemble the Kekulé valence structures, and two types of orbitals, that is, strictly atomic (local) and delocalized atomic (delocal) p-orbitals, were used to describe the π-system. It is found that the Pauling-Wheland's resonance energy with nonorthogonal structures decreases, while the same with orthogonalized structures and the total mean resonance energy (the sum of the weighted off-diagonal contributions in the Hamiltonian matrix of orthogonalized structures) increase when delocal orbitals are used as compared to local p-orbitals. Analysis of the interactions between the different structures of a system shows that the resonance in the 6π electrons conjugated circuits have the largest contributions to the resonance energy. The VBSCF calculations also show that the extra stability of phenanthrene, a kinked benzenoid, as compared to its linear counterpart, anthracene, is a consequence of the resonance in the π-system rather than the H-H interaction in the bay region as suggested previously. Finally, the empirical parameters for the resonance interactions between different 4n+2 or 4n π electrons conjugated circuits, used in Randić's conjugated circuits theory or Herdon's semi-emprical VB approach, are quantified. These parameters have to be scaled by the structure coefficients (weights) of the contributing structures.

  18. Identifying Facial Emotions: Valence Specific Effects and an Exploration of the Effects of Viewer Gender

    Science.gov (United States)

    Jansari, Ashok; Rodway, Paul; Goncalves, Salvador

    2011-01-01

    The valence hypothesis suggests that the right hemisphere is specialised for negative emotions and the left hemisphere is specialised for positive emotions (Silberman & Weingartner, 1986). It is unclear to what extent valence-specific effects in facial emotion perception depend upon the gender of the perceiver. To explore this question 46…

  19. Identifying Facial Emotions: Valence Specific Effects and an Exploration of the Effects of Viewer Gender

    Science.gov (United States)

    Jansari, Ashok; Rodway, Paul; Goncalves, Salvador

    2011-01-01

    The valence hypothesis suggests that the right hemisphere is specialised for negative emotions and the left hemisphere is specialised for positive emotions (Silberman & Weingartner, 1986). It is unclear to what extent valence-specific effects in facial emotion perception depend upon the gender of the perceiver. To explore this question 46…

  20. Dissociable modulation of overt visual attention in valence and arousal revealed by topology of scan path.

    Directory of Open Access Journals (Sweden)

    Jianguang Ni

    Full Text Available Emotional stimuli have evolutionary significance for the survival of organisms; therefore, they are attention-grabbing and are processed preferentially. The neural underpinnings of two principle emotional dimensions in affective space, valence (degree of pleasantness and arousal (intensity of evoked emotion, have been shown to be dissociable in the olfactory, gustatory and memory systems. However, the separable roles of valence and arousal in scene perception are poorly understood. In this study, we asked how these two emotional dimensions modulate overt visual attention. Twenty-two healthy volunteers freely viewed images from the International Affective Picture System (IAPS that were graded for affective levels of valence and arousal (high, medium, and low. Subjects' heads were immobilized and eye movements were recorded by camera to track overt shifts of visual attention. Algebraic graph-based approaches were introduced to model scan paths as weighted undirected path graphs, generating global topology metrics that characterize the algebraic connectivity of scan paths. Our data suggest that human subjects show different scanning patterns to stimuli with different affective ratings. Valence salient stimuli (with neutral arousal elicited faster and larger shifts of attention, while arousal salient stimuli (with neutral valence elicited local scanning, dense attention allocation and deep processing. Furthermore, our model revealed that the modulatory effect of valence was linearly related to the valence level, whereas the relation between the modulatory effect and the level of arousal was nonlinear. Hence, visual attention seems to be modulated by mechanisms that are separate for valence and arousal.

  1. Valence isomerization of cyclohepta-1,3,5-triene and its heteroelement analogues

    Directory of Open Access Journals (Sweden)

    Helen Jansen

    2011-12-01

    Full Text Available The valence isomerization of the all-carbon and heteroelement analogues of cyclohepta-1,3,5-triene into the corresponding bicyclo[4.1.0]hepta-2,4-dienes is reviewed to show the impact of the heteroatom on the stability of both valence isomers. The focus is on the parent systems and their synthetic applications.

  2. SPIN POLARIZATION AND MAGNETIC DICHROISM IN PHOTOEMISSION FROM CORE AND VALENCE STATES IN LOCALIZED MAGNETIC SYSTEMS

    NARCIS (Netherlands)

    THOLE, BT; VANDERLAAN, G

    1991-01-01

    Using group theory we derive a general model for spin polarization and magnetic dichroism in photo-emission in the presence of atomic interactions between the hole created and the valence holes. We predict strong effects in the photoemission from core levels and localized valence levels of

  3. Group Motivation and Group Task Performance: The Expectancy-Valence Theory Approach.

    Science.gov (United States)

    Nakanishi, Masayuki

    1988-01-01

    Investigated effects of group motivation on group task performance. Created two levels of valence, expectancy and instrumentality. Valence variable reflected on group productivity on unstructured and task persistence measures. Expectancy variable's effect was on task persistence measure. Instrumentality affected group productivity on structured…

  4. Atoms in Valence Bond – AiVB : synopsis and test results

    NARCIS (Netherlands)

    Zielinski, M.L.; van Lenthe, J.H.

    2010-01-01

    The Atoms in Valence Bond (AiVB) method, a new approach in the Valence Bond, is introduced. This approach combines the ideas behind the early Atoms in Molecules (AIM) developments, e.g. by Moffit [21], to understand a molecular wave function in terms of proper atomic wave functions, with the availab

  5. Development of an Analytical System for Rapid, Remote Determining Concentration and Valence of Uranium and Plutonium

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Concentrations and valence of U and Pu directly shows whether the Purex process is under normal conditions or not. It is necessary to monitor concentrations and valence of U and Pu in real-time.Purposes of this work is to develop an analytical

  6. SPIN POLARIZATION AND MAGNETIC DICHROISM IN PHOTOEMISSION FROM CORE AND VALENCE STATES IN LOCALIZED MAGNETIC SYSTEMS

    NARCIS (Netherlands)

    THOLE, BT; VANDERLAAN, G

    1991-01-01

    Using group theory we derive a general model for spin polarization and magnetic dichroism in photo-emission in the presence of atomic interactions between the hole created and the valence holes. We predict strong effects in the photoemission from core levels and localized valence levels of transitio

  7. Emotions and language about motion: Differentiating affective dominance with syntax from valence with semantics.

    Science.gov (United States)

    Freddi, Sébastien; Esteban, José; Dru, Vincent

    2015-12-15

    Motion as encoded in linguistic cues is used to differentiate affective valence and dominance. Participants were invited to rate their affective responses to different words along valence and dominance scales. The words were nouns describing static cues and verbs describing motion, connected to DOWN/UP and Avoidance/Approach cues. The results of three studies showed that valence and dominance could be differentiated through syntax and semantics of motion. On one hand, dominance feelings, compared to valence ones, are particularly influenced by motion encoded in syntactic classes (verbs vs. nouns). On the other hand, valence feelings, compared to dominance ones, are influenced by a semantics of motion through DOWN/UP and Avoidance/Approach cues, considered as polarities. A polarity correspondence effect is proposed to explain these results.

  8. Effects of valence and arousal on written word recognition: time course and ERP correlates.

    Science.gov (United States)

    Citron, Francesca M M; Weekes, Brendan S; Ferstl, Evelyn C

    2013-01-15

    Models of affect assume a two-dimensional framework, composed of emotional valence and arousal. Although neuroimaging evidence supports a neuro-functional distinction of their effects during single word processing, electrophysiological studies have not yet compared the effects of arousal within the same category of valence (positive and negative). Here we investigate effects of arousal and valence on written lexical decision. Amplitude differences between emotion and neutral words were seen in the early posterior negativity (EPN), the late positive complex and in a sustained slow positivity. In addition, trends towards interactive effects of valence and arousal were observed in the EPN, showing larger amplitude for positive, high-arousal and negative, low-arousal words. The results provide initial evidence for interactions between arousal and valence during processing of positive words and highlight the importance of both variables in studies of emotional stimulus processing. Crown Copyright © 2012. Published by Elsevier Ireland Ltd. All rights reserved.

  9. Examining the role of emotional valence of mind wandering: All mind wandering is not equal.

    Science.gov (United States)

    Banks, Jonathan B; Welhaf, Matthew S; Hood, Audrey V B; Boals, Adriel; Tartar, Jaime L

    2016-07-01

    To evaluate the role of emotional valence on the impact of mind wandering on working memory (WM) and sustained attention, we reanalyzed data from three independently conducted studies that examined the impact of stress on WM (Banks & Boals, 2016; Banks, Welhaf, & Srour, 2015) and sustained attention (Banks, Tartar, & Welhaf, 2014). Across all studies, participants reported the content of their thoughts at random intervals during the WM or sustained attention task. Thought probes in all studies included a core set of response options for task-unrelated thoughts (TUTs) that were negatively, positively, or neutrally emotionally valenced. In line with theories of emotional valenced stimuli on capture of attention, results suggest negatively valenced TUTs, but not positively valenced TUTs, were related to poorer WM and sustained attention in two studies. Neutral TUTs were related to poorer WM but not sustained attention performance. Implications for models of mind wandering are discussed.

  10. Virtual Distance and Soundstage, and their Impacts on Experienced Emotional Valence

    DEFF Research Database (Denmark)

    Christensen, Justin

    2015-01-01

    Research from animal ethology and affective neuroscience suggest that a listener’s perceived distance from a signal source can alter their experienced emotional valence of the music. Furthermore, appraisal theories of emotion suggest that emotionally valenced responses will diverge according to t...... valenced in nearfield. The results are largely consistent with this hypothesis, but can also be found to be impacted by the original soundstage of the musical excerpts presented....... to the type of emotion presented. For these exploratory investigations, subjects listen to selected musical excerpts on speakers in combination with a tactile transducer attached to their chair. The listening sessions are recorded on EEG supported by subject feedback responses. My hypothesis is that musical......Research from animal ethology and affective neuroscience suggest that a listener’s perceived distance from a signal source can alter their experienced emotional valence of the music. Furthermore, appraisal theories of emotion suggest that emotionally valenced responses will diverge according...

  11. Influence of emotional valence and arousal on the spread of activation in memory.

    Science.gov (United States)

    Jhean-Larose, Sandra; Leveau, Nicolas; Denhière, Guy

    2014-11-01

    Controversy still persists on whether emotional valence and arousal influence cognitive activities. Our study sought to compare how these two factors foster the spread of activation within the semantic network. In a lexical decision task, prime words were varied depending on the valence (pleasant or unpleasant) or on the level of emotional arousal (high or low). Target words were carefully selected to avoid semantic priming effects, as well as to avoid arousing specific emotions (neutral). Three SOA durations (220, 420 and 720 ms) were applied across three independent groups. Results indicate that at 220 ms, the effect of arousal is significantly higher than the effect of valence in facilitating spreading activation while at 420 ms, the effect of valence is significantly higher than the effect of arousal in facilitating spreading activation. These findings suggest that affect is a sequential process involving the successive intervention of arousal and valence.

  12. Uranyl ion coordination

    Science.gov (United States)

    Evans, H.T.

    1963-01-01

    A review of the known crystal structures containing the uranyl ion shows that plane-pentagon coordination is equally as prevalent as plane-square or plane-hexagon. It is suggested that puckered-hexagon configurations of OH - or H2O about the uranyl group will tend to revert to plane-pentagon coordination. The concept of pentagonal coordination is invoked for possible explanations of the complex crystallography of the natural uranyl hydroxides and the unusual behavior of polynuclear ions in hydrolyzed uranyl solutions.

  13. Magnetic Coordinate Systems

    CERN Document Server

    Laundal, K M

    2016-01-01

    Geospace phenomena such as the aurora, plasma motion, ionospheric currents and associated magnetic field disturbances are highly organized by Earth's main magnetic field. This is due to the fact that the charged particles that comprise space plasma can move almost freely along magnetic field lines, but not across them. For this reason it is sensible to present such phenomena relative to Earth's magnetic field. A large variety of magnetic coordinate systems exist, designed for different purposes and regions, ranging from the magnetopause to the ionosphere. In this paper we review the most common magnetic coordinate systems and describe how they are defined, where they are used, and how to convert between them. The definitions are presented based on the spherical harmonic expansion coefficients of the International Geomagnetic Reference Field (IGRF) and, in some of the coordinate systems, the position of the Sun which we show how to calculate from the time and date. The most detailed coordinate systems take the...

  14. Supercritical Airfoil Coordinates

    Data.gov (United States)

    National Aeronautics and Space Administration — Rectangular Supercritical Wing (Ricketts) - design and measured locations are provided in an Excel file RSW_airfoil_coordinates_ricketts.xls . One sheet is with Non...

  15. Understanding social motor coordination.

    Science.gov (United States)

    Schmidt, R C; Fitzpatrick, Paula; Caron, Robert; Mergeche, Joanna

    2011-10-01

    Recently there has been much interest in social coordination of motor movements, or as it is referred to by some researchers, joint action. This paper reviews the cognitive perspective's common coding/mirror neuron theory of joint action, describes some of its limitations and then presents the behavioral dynamics perspective as an alternative way of understanding social motor coordination. In particular, behavioral dynamics' ability to explain the temporal coordination of interacting individuals is detailed. Two experiments are then described that demonstrate how dynamical processes of synchronization are apparent in the coordination underlying everyday joint actions such as martial art exercises, hand-clapping games, and conversations. The import of this evidence is that emergent dynamic patterns such as synchronization are the behavioral order that any neural substrate supporting joint action (e.g., mirror systems) would have to sustain.

  16. Environmental Compliance Issue Coordination

    Science.gov (United States)

    An order to establish the Department of Energy (DOE) requirements for coordination of significant environmental compliance issues to ensure timely development and consistent application of Departmental environmental policy and guidance

  17. [Coordination and donation].

    Science.gov (United States)

    Elizalde, J; Lorente, M

    2006-01-01

    The progressive incorporation of organ transplants as a therapeutic resource resulted in organisational adaptation and overall transplant management, leading to the emergence of the figure of the transplant coordinator in the mid-1980s. In Spain, the National Organisation of Transplants (Organización Nacional de Transplantes - ONT) was created, establishing a system - called the "Spanish model" - based on a network of coordinators at three levels: national, the autonomous community and the hospital. This organisational structure is a point of reference at the world level. The prevalence of the Intensive Medicine specialisation amongst hospital transplant coordinators is remarkable. The majority of organs proceed from brain-dead patients with beating hearts and this requires the infrastructure offered by intensive care units. The functions of the coordinator can be summarised in guaranteeing a synchrony of all the elements and teams that come together in an organisational chain that has come to be called the "process of donation". Schematically, the crucial points that the hospital coordinator develops are the following: - Detection of the potential donor. - Maintenance of the donor. - Diagnosis of brain death. - Family consent. - Preparation of the hospital logistics. - Helping the relatives. - Direct involvement in the Program of Guarantee of Quality. - Person of reference in any activity related to the transplant. It would be desirable to achieve the creation of transplant coordination teams, with univocal messages, professionalism and a permanent input of the so-called "human factor", which is so necessary and also so close to the transplant world.

  18. Continuous parallel coordinates.

    Science.gov (United States)

    Heinrich, Julian; Weiskopf, Daniel

    2009-01-01

    Typical scientific data is represented on a grid with appropriate interpolation or approximation schemes,defined on a continuous domain. The visualization of such data in parallel coordinates may reveal patterns latently contained in the data and thus can improve the understanding of multidimensional relations. In this paper, we adopt the concept of continuous scatterplots for the visualization of spatially continuous input data to derive a density model for parallel coordinates. Based on the point-line duality between scatterplots and parallel coordinates, we propose a mathematical model that maps density from a continuous scatterplot to parallel coordinates and present different algorithms for both numerical and analytical computation of the resulting density field. In addition, we show how the 2-D model can be used to successively construct continuous parallel coordinates with an arbitrary number of dimensions. Since continuous parallel coordinates interpolate data values within grid cells, a scalable and dense visualization is achieved, which will be demonstrated for typical multi-variate scientific data.

  19. Magnetic Coordinate Systems

    Science.gov (United States)

    Laundal, K. M.; Richmond, A. D.

    2017-03-01

    Geospace phenomena such as the aurora, plasma motion, ionospheric currents and associated magnetic field disturbances are highly organized by Earth's main magnetic field. This is due to the fact that the charged particles that comprise space plasma can move almost freely along magnetic field lines, but not across them. For this reason it is sensible to present such phenomena relative to Earth's magnetic field. A large variety of magnetic coordinate systems exist, designed for different purposes and regions, ranging from the magnetopause to the ionosphere. In this paper we review the most common magnetic coordinate systems and describe how they are defined, where they are used, and how to convert between them. The definitions are presented based on the spherical harmonic expansion coefficients of the International Geomagnetic Reference Field (IGRF) and, in some of the coordinate systems, the position of the Sun which we show how to calculate from the time and date. The most detailed coordinate systems take the full IGRF into account and define magnetic latitude and longitude such that they are constant along field lines. These coordinate systems, which are useful at ionospheric altitudes, are non-orthogonal. We show how to handle vectors and vector calculus in such coordinates, and discuss how systematic errors may appear if this is not done correctly.

  20. A valence bond model for aqueous Cu(II) and Zn(II) ions in the AMOEBA polarizable force field.

    Science.gov (United States)

    Xiang, Jin Yu; Ponder, Jay W

    2013-04-05

    A general molecular mechanics (MM) model for treating aqueous Cu(2+) and Zn(2+) ions was developed based on valence bond (VB) theory and incorporated into the atomic multipole optimized energetics for biomolecular applications (AMOEBA) polarizable force field. Parameters were obtained by fitting MM energies to that computed by ab initio methods for gas-phase tetra- and hexa-aqua metal complexes. Molecular dynamics (MD) simulations using the proposed AMOEBA-VB model were performed for each transition metal ion in aqueous solution, and solvent coordination was evaluated. Results show that the AMOEBA-VB model generates the correct square-planar geometry for gas-phase tetra-aqua Cu(2+) complex and improves the accuracy of MM model energetics for a number of ligation geometries when compared to quantum mechanical (QM) computations. On the other hand, both AMOEBA and AMOEBA-VB generate results for Zn(2+)-water complexes in good agreement with QM calculations. Analyses of the MD trajectories revealed a six-coordination first solvation shell for both Cu(2+) and Zn(2+) ions in aqueous solution, with ligation geometries falling in the range reported by previous studies. Copyright © 2012 Wiley Periodicals, Inc.

  1. [XPS study on the influence of calcination conditions to cerium ion valence].

    Science.gov (United States)

    Mei, Yan; Yan, Jian-ping; Nie, Zuo-ren

    2010-01-01

    For the system of Ce(NO3)2.6H2O and urea solution during homogeneous precipitation method, X-ray diffraction (XRD), infrared spectrum (IR) and especially X-ray photoelectron spectroscopy (XPS) were used to study and characterize the product structure, variety of cerium ion valence, compound surface character and kernel electronic configurations. The results of XRD and IR showed that calcination temperature had a great effect on the cerium ion valence. The products are orthorhombic Ce2 O(CO3)2.H2O with valence III by using homogeneous precipitation method directly. When heated from the temperature 200 degrees C to 250 degrees C, the product of CeO(CO3)2.H2O with valence VI was finally changed into stable CeO2 with valence IV. XPS was used to study the surface character and kernel electronic configurations of the three different compounds through fine scanning of O(1s), Ce(3d) and Ce(4d) apices, and the results approved that the compounds with different valences are caused by the different valence electronic configurations of the products.

  2. High and low roads to odor valence? A choice response-time study.

    Science.gov (United States)

    Olofsson, Jonas K; Bowman, Nicholas E; Gottfried, Jay A

    2013-10-01

    Valence and edibility are two important features of olfactory perception, but it remains unclear how they are read out from an olfactory input. For a given odor object (e.g., the smell of rose or garlic), does perceptual identification of that object necessarily precede retrieval of information about its valence and edibility, or alternatively, are these processes independent? In the present study, we studied rapid, binary perceptual decisions regarding odor detection, object identity, valence, and edibility for a set of common odors. We found that decisions regarding odor-object identity were faster than decisions regarding odor valence or edibility, but slower than detection. Mediation analysis revealed that odor valence and edibility decision response times were predicted by a model in which odor-object identity served as a mediator along the perceptual pathway from detection to both valence and edibility. According to this model, odor valence is determined through both a "low road" that bypasses odor objects and a "high road" that utilizes odor-object information. Edibility evaluations are constrained to processing via the high road. The results outline a novel causal framework that explains how major perceptual features might be rapidly extracted from odors through engagement of odor objects early in the processing stream.

  3. The Polarised Valence Quark Distribution from semi-inclusive DIS

    CERN Document Server

    Alekseev, M.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Arbuzov, A.; Badelek, B.; Balestra, F.; Ball, J.; Barth, J.; Baum, G.; Bedfer, Y.; Bernet, C.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.P.; Chapiro, A.; Chiosso, M.; Cicuttin, A.; Colantoni, M.; Costa, S.; Crespo, M.L.; Dalla Torre, S.; Dafni, T.; Das, S.; Dasgupta, S.S.; De Masi, R.; Dedek, N.; Denisov, O.Yu.; Dhara, L.; Diaz, V.; Dinkelbach, A.M.; Donskov, S.V.; Dorofeev, V.A.; Doshita, N.; Duic, V.; Dunnweber, W.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Falaleev, V.; Ferrero, A.; Ferrero, L.; Finger, M.; Finger, M., Jr.; Fischer, H.; Franco, C.; Franz, J.; Friedrich, J.M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gobbo, B.; Goertz, S.; Gorin, A.M.; Grabmuller, S.; Grajek, O.A.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; Hannappel, J.; von Harrach, D.; Hasegawa, T.; Heckmann, J.; Hedicke, S.; Heinsius, F.H.; Hermann, R.; Hess, C.; Hinterberger, F.; von Hodenberg, M.; Horikawa, N.; Horikawa, S.; d'Hose, N.; Ilgner, C.; Ioukaev, A.I.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Janata, A.; Jasinski, P.; Joosten, R.; Jouravlev, N.I.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Komissarov, E.V.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Korentchenko, A.S.; Korzenev, A.; Kotzinian, A.M.; Koutchinski, N.A.; Kouznetsov, O.; Kral, A.; Kravchuk, N.P.; Kroumchtein, Z.V.; Kuhn, R.; Kunne, F.; Kurek, K.; Ladygin, M.E.; Lamanna, M.; Le Goff, J.M.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Ludwig, I.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.K.; Mann, A.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Maximov, A.N.; Meyer, W.; Mielech, A.; Mikhailov, Yu.V.; Moinester, M.A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nahle, O.; Nassalski, J.; Neliba, S.; Nerling, F.; Neubert, S.; Neyret, D.P.; Nikolaenko, V.I.; Nikolaev, K.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Pagano, P.; Panebianco, S.; Panknin, R.; Panzieri, D.; Paul, S.; Pawlukiewicz-Kaminska, B.; Peshekhonov, D.V.; Peshekhonov, V.D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pretz, J.; Procureur, S.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Reggiani, D.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Rozhdestvensky, A.M.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Santos, H.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Schiavon, P.; Schill, C.; Schmitt, L.; Schonmeier, P.; Schroder, W.; Shevchenko, O.Yu.; Siebert, H.W.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Stinzing, F.; Stolarski, M.; Sugonyaev, V.P.; Sulc, M.; Sulej, R.; Tchalishev, V.V.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.G.; Venugopal, G.; Virius, M.; Vlassov, N.V.; Vossen, A.; Webb, R.; Weise, E.; Weitzel, Q.; Windmolders, R.; Wirth, S.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Zhao, J.; Ziegler, R.; Zvyagin, A.

    2008-01-01

    The semi-inclusive difference asymmetry A^{h+ - h-} for hadrons of opposite charge has been measured by the COMPASS experiment at CERN. The data were collected in the years 2002-2004 using a 160 GeV polarised muon beam scattered off a large polarised 6-LiD target and cover the range 0.006 < x < 0.7 and 1 < Q^2 < 100 (GeV/c)^2. In leading order QCD (LO) the asymmetry A_d^{h+ - h-} measures the valence quark polarisation and provides an evaluation of the first moment of Delta u_v + Delta d_v which is found to be equal to 0.40 +- 0.07 (stat.) +- 0.05 (syst.) over the measured range of x at Q^2 = 10 (GeV/c)^2. When combined with the first moment of g_1^d previously measured on the same data, this result favours a non-symmetric polarisation of light quarks Delta u-bar = -Delta d-bar at a confidence level of two standard deviations, in contrast to the often assumed symmetric scenario Delta u-bar = Delta d-bar = Delta s-bar = Delta s.

  4. Valence Topological Charge-Transfer Indices for Dipole Moments

    Directory of Open Access Journals (Sweden)

    Francisco Torrens

    2003-01-01

    Full Text Available New valence topological charge-transfer indices are applied to the calculation of dipole moments. The algebraic and vector semisum charge-transfer indices are defined. The combination of the charge-transfer indices allows the estimation of the dipole moments. The model is generalized for molecules with heteroatoms. The ability of the indices for the description of the molecular charge distribution is established by comparing them with the dipole moments of a homologous series of phenyl alcohols. Linear and non-linear correlation models are obtained. The new charge-transfer indices improve the multivariable non-linear regression equations for the dipole moment. When comparing with previous results, the variance decreases 92%. No superposition of the corresponding Gk–Jk and GkV – JkV pairs is observed. This diminishes the risk of co-linearity. Inclusion of the oxygen atom in the p-electron system is beneficial for the description of the dipole moment, owing to either the role of the additional p orbitals provided by the heteroatom or the role of steric factors in the p-electron conjugation. Linear and non-linear correlations between the fractal dimension and various descriptors point not only to a homogeneous molecular structure but also to the ability to predict and tailor drug properties.

  5. The genetics of anxiety-related negative valence system traits.

    Science.gov (United States)

    Savage, Jeanne E; Sawyers, Chelsea; Roberson-Nay, Roxann; Hettema, John M

    2017-03-01

    NIMH's Research Domain Criteria (RDoC) domain of negative valence systems (NVS) captures constructs of negative affect such as fear and distress traditionally subsumed under the various internalizing disorders. Through its aims to capture dimensional measures that cut across diagnostic categories and are linked to underlying neurobiological systems, a large number of phenotypic constructs have been proposed as potential research targets. Since "genes" represent a central "unit of analysis" in the RDoC matrix, it is important for studies going forward to apply what is known about the genetics of these phenotypes as well as fill in the gaps of existing knowledge. This article reviews the extant genetic epidemiological data (twin studies, heritability) and molecular genetic association findings for a broad range of putative NVS phenotypic measures. We find that scant genetic epidemiological data is available for experimentally derived measures such as attentional bias, peripheral physiology, or brain-based measures of threat response. The molecular genetic basis of NVS phenotypes is in its infancy, since most studies have focused on a small number of candidate genes selected for putative association to anxiety disorders (ADs). Thus, more research is required to provide a firm understanding of the genetic aspects of anxiety-related NVS constructs. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Valence atom with bohmian quantum potential: the golden ratio approach

    Directory of Open Access Journals (Sweden)

    Putz Mihai V

    2012-11-01

    Full Text Available Abstract Background The alternative quantum mechanical description of total energy given by Bohmian theory was merged with the concept of the golden ratio and its appearance as the Heisenberg imbalance to provide a new density-based description of the valence atomic state and reactivity charge with the aim of clarifying their features with respect to the so-called DFT ground state and critical charge, respectively. Results The results, based on the so-called double variational algorithm for chemical spaces of reactivity, are fundamental and, among other issues regarding chemical bonding, solve the existing paradox of using a cubic parabola to describe a quadratic charge dependency. Conclusions Overall, the paper provides a qualitative-quantitative explanation of chemical reactivity based on more than half of an electronic pair in bonding, and provide new, more realistic values for the so-called “universal” electronegativity and chemical hardness of atomic systems engaged in reactivity (analogous to the atoms-in-molecules framework.

  7. Two Meson Systems with Ginsparg-Wilson Valence Quarks

    CERN Document Server

    Chen, J W; Walker-Loud, A; Chen, Jiunn-Wei; Connell, Donal O'; Walker-Loud, Andre

    2006-01-01

    Unphysical effects associated with finite lattice spacing and partial quenching may lead to the presence of unphysical terms in chiral extrapolation formulae. These unphysical terms must then be removed during data analysis before physical predictions can be made. In this work, we show that through next-to-leading order, there are no unphysical counterterms in the extrapolation formulae, expressed in lattice-physical parameters, for meson scattering lengths in theories with Ginsparg-Wilson valence quarks. Our work applies to essentially any sea quark discretization, provided that chiral perturbation theory is a valid approximation. We demonstrate our results with explicit computations and show that, in favorable circumstances, the extrapolation formulae do not depend on the unknown constant C_Mix appearing at lowest order in the mixed action chiral Lagrangian. We show that the I=1 K-K scattering length does not depend on C_Mix in contrast to the I = 3/2 K-pi scattering length. In addition, we show that these ...

  8. Improving Robot Motor Learning with Negatively Valenced Reinforcement Signals.

    Science.gov (United States)

    Navarro-Guerrero, Nicolás; Lowe, Robert J; Wermter, Stefan

    2017-01-01

    Both nociception and punishment signals have been used in robotics. However, the potential for using these negatively valenced types of reinforcement learning signals for robot learning has not been exploited in detail yet. Nociceptive signals are primarily used as triggers of preprogrammed action sequences. Punishment signals are typically disembodied, i.e., with no or little relation to the agent-intrinsic limitations, and they are often used to impose behavioral constraints. Here, we provide an alternative approach for nociceptive signals as drivers of learning rather than simple triggers of preprogrammed behavior. Explicitly, we use nociception to expand the state space while we use punishment as a negative reinforcement learning signal. We compare the performance-in terms of task error, the amount of perceived nociception, and length of learned action sequences-of different neural networks imbued with punishment-based reinforcement signals for inverse kinematic learning. We contrast the performance of a version of the neural network that receives nociceptive inputs to that without such a process. Furthermore, we provide evidence that nociception can improve learning-making the algorithm more robust against network initializations-as well as behavioral performance by reducing the task error, perceived nociception, and length of learned action sequences. Moreover, we provide evidence that punishment, at least as typically used within reinforcement learning applications, may be detrimental in all relevant metrics.

  9. Valence Scaling of Dynamic Facial Expressions Is Altered in High-Functioning Subjects with Autism Spectrum Disorders: An FMRI Study

    Science.gov (United States)

    Rahko, Jukka S.; Paakki, Jyri-Johan; Starck, Tuomo H.; Nikkinen, Juha; Pauls, David L.; Katsyri, Jari V.; Jansson-Verkasalo, Eira M.; Carter, Alice S.; Hurtig, Tuula M.; Mattila, Marja-Leena; Jussila, Katja K.; Remes, Jukka J.; Kuusikko-Gauffin, Sanna A.; Sams, Mikko E.; Bolte, Sven; Ebeling, Hanna E.; Moilanen, Irma K.; Tervonen, Osmo; Kiviniemi, Vesa

    2012-01-01

    FMRI was performed with the dynamic facial expressions fear and happiness. This was done to detect differences in valence processing between 25 subjects with autism spectrum disorders (ASDs) and 27 typically developing controls. Valence scaling was abnormal in ASDs. Positive valence induces lower deactivation and abnormally strong activity in ASD…

  10. Positively valenced stimuli facilitate creative novel metaphoric processes by enhancing medial prefrontal cortical activation.

    Science.gov (United States)

    Subramaniam, Karuna; Beeman, Mark; Faust, Miriam; Mashal, Nira

    2013-01-01

    A metaphor is a figure of speech in which a subject is symbolic of another unrelated object. In the present study, we examined neural patterns associated with both novel unfamiliar and conventional familiar metaphoric processing, and how these patterns are modulated by affective valence. Prior to fMRI scanning, participants received a list of word pairs (novel unfamiliar metaphors as well as conventional familiar metaphors) and were asked to denote the valence (positive, negative, or neutral) of each word pair. During scanning, participants had to decide whether the word pairs formed meaningful or meaningless expressions. Results indicate that participants were faster and more accurate at deciding that positively valenced metaphors were meaningful compared to neutral metaphors. These behavioral findings were accompanied by increased activation in the medial prefrontal cortex (mPFC), posterior cingulate cortex (PCC), and the right inferior parietal lobe (RIPL). Specifically, positively valenced novel unfamiliar metaphors elicited activation in these brain regions in addition to the left superior temporal gyrus when compared to neutral novel metaphors. We also found that the mPFC and PCC mediated the processing of positively valenced metaphors when compared to negatively valenced metaphors. Positively valenced conventional metaphors, however, elicited different neural signatures when contrasted with either neutral or negatively valenced conventional metaphors. Together, our results indicate that positively valenced stimuli facilitate creative metaphoric processes (specifically novel metaphoric processes) by mediating attention and cognitive control processes required for the access, integration, and selection of semantic associations via modulation of the mPFC. The present study is important for the development of neural accounts of emotion-cognition interactions required for creativity, language, and successful social functioning in general.

  11. Valence bond phases in S = 1/2 Kane-Mele-Heisenberg model.

    Science.gov (United States)

    Zare, Mohammad H; Mosadeq, Hamid; Shahbazi, Farhad; Jafari, S A

    2014-11-12

    The phase diagram of the Kane-Mele-Heisenberg model in a classical limit [47] contains disordered regions in the coupling space, as the result of competition between different terms in the Hamiltonian, leading to frustration in finding a unique ground state. In this work we explore the nature of these phases in the quantum limit, for a S = 1/2. Employing exact diagonalization in Sz and nearest neighbour valence bond bases, and bond and plaquette valence bond mean field theories, we show that the disordered regions are divided into ordered quantum states in the form of plaquette valence bond crystals and staggered dimerized phases.

  12. Coordinating Interactions: The Event Coordination Notation

    DEFF Research Database (Denmark)

    Kindler, Ekkart

    on a much more technical level. The Event Coordination Notation (ECNO) allows modelling the behaviour of an application on a high level of abstraction that is closer to the application’s domain than to the software realizing it. Still, these models contain all necessary details for actually executing...... implementation of ECNO, which consists of a modelling environment based on Eclipse and the Eclipse Modeling Framework (EMF) and an execution engine, which fully supports all the concepts and features of ECNO discussed in this technical report. All the examples are based on EMF, but the ECNO Engine can be used......The purpose of a domain model is to concisely capture the concepts of an application’s domain, and their relation among each other. Even though the main purpose of domain models is not on implementing the application, major parts of an application can be generated from the application’s domain...

  13. Quantifying linguistic coordination

    DEFF Research Database (Denmark)

    Fusaroli, Riccardo; Tylén, Kristian

    ). We employ nominal recurrence analysis (Orsucci et al 2005, Dale et al 2011) on the decision-making conversations between the participants. We report strong correlations between various indexes of recurrence and collective performance. We argue this method allows us to quantify the qualities......Language has been defined as a social coordination device (Clark 1996) enabling innovative modalities of joint action. However, the exact coordinative dynamics over time and their effects are still insufficiently investigated and quantified. Relying on the data produced in a collective decision...

  14. Introduction to Coordination Chemistry

    CERN Document Server

    Lawrance, Geoffrey Alan

    2010-01-01

    Introduction to Coordination Chemistry examines and explains how metals and molecules that bind as ligands interact, and the consequences of this assembly process. This book describes the chemical and physical properties and behavior of the complex assemblies that form, and applications that may arise as a result of these properties. Coordination complexes are an important but often hidden part of our world?even part of us?and what they do is probed in this book. This book distills the essence of this topic for undergraduate students and for research scientists.

  15. Coordinate Standard Measurement Development

    Energy Technology Data Exchange (ETDEWEB)

    Hanshaw, R.A.

    2000-02-18

    A Shelton Precision Interferometer Base, which is used for calibration of coordinate standards, was improved through hardware replacement, software geometry error correction, and reduction of vibration effects. Substantial increases in resolution and reliability, as well as reduction in sampling time, were achieved through hardware replacement; vibration effects were reduced substantially through modification of the machine component dampening and software routines; and the majority of the machine's geometry error was corrected through software geometry error correction. Because of these modifications, the uncertainty of coordinate standards calibrated on this device has been reduced dramatically.

  16. Valence, arousal, and task effects in emotional prosody processing

    Directory of Open Access Journals (Sweden)

    Silke ePaulmann

    2013-06-01

    Full Text Available Previous research suggests that emotional prosody processing is a highly rapid and complex process. In particular, it has been shown that different basic emotions can be differentiated in an early event-related brain potential (ERP component, the P200. Often, the P200 is followed by later long lasting ERPs such as the late positive complex (LPC. The current experiment set out to explore in how far emotionality and arousal can modulate these previously reported ERP components. In addition, we also investigated the influence of task demands (implicit vs. explicit evaluation of stimuli. Participants listened to pseudo-sentences (sentences with no lexical content spoken in six different emotions or in a neutral tone of voice while they either rated the arousal level of the speaker or their own arousal level. Results confirm that different emotional intonations can first be differentiated in the P200 component, reflecting a first emotional encoding of the stimulus possibly including a valence tagging process. A marginal significant arousal effect was also found in this time-window with high arousing stimuli eliciting a stronger P200 than low arousing stimuli. The P200 component was followed by a long lasting positive ERP between 400 and 750 ms. In this late time-window, both emotion and arousal effects were found. No effects of task were observed in either time-window. Taken together, results suggest that emotion relevant details are robustly decoded during early processing and late processing stages while arousal information is only reliably taken into consideration at a later stage of processing.

  17. Chemical Bonding: The Orthogonal Valence-Bond View

    Directory of Open Access Journals (Sweden)

    Alexander F. Sax

    2015-04-01

    Full Text Available Chemical bonding is the stabilization of a molecular system by charge- and spin-reorganization processes in chemical reactions. These processes are said to be local, because the number of atoms involved is very small. With multi-configurational self-consistent field (MCSCF wave functions, these processes can be calculated, but the local information is hidden by the delocalized molecular orbitals (MO used to construct the wave functions. The transformation of such wave functions into valence bond (VB wave functions, which are based on localized orbitals, reveals the hidden information; this transformation is called a VB reading of MCSCF wave functions. The two-electron VB wave functions describing the Lewis electron pair that connects two atoms are frequently called covalent or neutral, suggesting that these wave functions describe an electronic situation where two electrons are never located at the same atom; such electronic situations and the wave functions describing them are called ionic. When the distance between two atoms decreases, however, every covalent VB wave function composed of non-orthogonal atomic orbitals changes its character from neutral to ionic. However, this change in the character of conventional VB wave functions is hidden by its mathematical form. Orthogonal VB wave functions composed of orthonormalized orbitals never change their character. When localized fragment orbitals are used instead of atomic orbitals, one can decide which local information is revealed and which remains hidden. In this paper, we analyze four chemical reactions by transforming the MCSCF wave functions into orthogonal VB wave functions; we show how the reactions are influenced by changing the atoms involved or by changing their local symmetry. Using orthogonal instead of non-orthogonal orbitals is not just a technical issue; it also changes the interpretation, revealing the properties of wave functions that remain otherwise undetected.

  18. Overlap valence quarks on a twisted mass sea. A case study for mixed action lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Cichy, Krzysztof [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Poznan Univ. (Poland). Faculty of Physics; Drach, Vincent; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Garcia-Ramos, Elena [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Humboldt-Universitaet, Berlin (Germany); Herdoiza, Gregorio [UAM/CSIC Univ. Autonoma de Madrid (Spain). Dept. de Fisica Teorica; UAM/CSIC Univ. Autonoma de Madrid (Spain). Inst. de Fisica Teorica; Collaboration: European Twisted Mass Collaboration

    2012-11-15

    We discuss a Lattice QCD mixed action investigation employing Wilson maximally twisted mass sea and overlap valence fermions. Using four values of the lattice spacing, we demonstrate that the overlap Dirac operator assumes a point-like locality in the continuum limit. We also show that by adopting suitable matching conditions for the sea and valence theories a consistent continuum limit for the pion decay constant and light baryon masses can be obtained. Finally, we confront results for sea-valence mixed meson masses and the valence scalar correlator with corresponding expressions of chiral perturbation theory. This allows us to extract low energy constants of mixed action chiral perturbation which characterize the strength of unitarity violations in our mixed action setup.

  19. Reproducing affective norms with lexical co-occurrence statistics: Predicting valence, arousal, and dominance.

    Science.gov (United States)

    Recchia, Gabriel; Louwerse, Max M

    2015-01-01

    Human ratings of valence, arousal, and dominance are frequently used to study the cognitive mechanisms of emotional attention, word recognition, and numerous other phenomena in which emotions are hypothesized to play an important role. Collecting such norms from human raters is expensive and time consuming. As a result, affective norms are available for only a small number of English words, are not available for proper nouns in English, and are sparse in other languages. This paper investigated whether affective ratings can be predicted from length, contextual diversity, co-occurrences with words of known valence, and orthographic similarity to words of known valence, providing an algorithm for estimating affective ratings for larger and different datasets. Our bootstrapped ratings achieved correlations with human ratings on valence, arousal, and dominance that are on par with previously reported correlations across gender, age, education and language boundaries. We release these bootstrapped norms for 23,495 English words.

  20. Valence band structure of binary chalcogenide vitreous semiconductors by high-resolution XPS

    Energy Technology Data Exchange (ETDEWEB)

    Kozyukhin, S., E-mail: sergkoz@igic.ras.ru [Russian Academy of Science, Institute of General and Inorganic Chemistry (Russian Federation); Golovchak, R. [Lviv Scientific Research Institute of Materials of SRC ' Carat' (Ukraine); Kovalskiy, A. [Lehigh University, Department of Materials Science and Engineering (United States); Shpotyuk, O. [Lviv Scientific Research Institute of Materials of SRC ' Carat' (Ukraine); Jain, H. [Lehigh University, Department of Materials Science and Engineering (United States)

    2011-04-15

    High-resolution X-ray photoelectron spectroscopy (XPS) is used to study regularities in the formation of valence band electronic structure in binary As{sub x}Se{sub 100-x}, As{sub x}S{sub 100-x}, Ge{sub x}Se{sub 100-x} and Ge{sub x}S{sub 100-x} chalcogenide vitreous semiconductors. It is shown that the highest occupied energetic states in the valence band of these materials are formed by lone pair electrons of chalcogen atoms, which play dominant role in the formation of valence band electronic structure of chalcogen-rich glasses. A well-expressed contribution from chalcogen bonding p electrons and more deep s orbitals are also recorded in the experimental valence band XPS spectra. Compositional dependences of the observed bands are qualitatively analyzed from structural and compositional points of view.

  1. Determination of the bulk cobalt valence state of co-perovskites containing surface-adsorbed impurities.

    Science.gov (United States)

    Haas, O; Ludwig, Chr; Wokaun, A

    2006-10-15

    We used thermogravimetric hydrogen reduction and iodometric titration to determine the bulk valence state of cobalt in Co-perovskites containing surface carbonate hydroxide or hydroxyl groups. It could be shown that thermogravimetric hydrogen reduction experiments are very sensitive to volatile surface groups, but due to their volatility, they can be specified and the bulk valence state of cobalt can still be deduced from these experiments. The iodometric titration is less sensitive to small volatile surface impurities, but precaution has to be taken that oxygen or iodine does not escape from the solution during dissolution of the sample. Best results were obtained if the sample was titrated during dissolution in a closed argon floated titration apparatus. We tested the two methods using LaCoO3 perovskite as a sample with a known valence state. Both methods delivered satisfactory results, and the valence state could be determined with an accuracy of better than 1%.

  2. Coordination failure caused by sunspots

    DEFF Research Database (Denmark)

    Beugnot, Julie; Gürgüç, Zeynep; Øvlisen, Frederik Roose

    2012-01-01

    In a coordination game with Pareto-ranked equilibria, we study whether a sunspot can lead to either coordination on an inferior equilibrium (mis-coordination) or to out-of equilibrium behavior (dis-coordination). While much of the literature searches for mechanisms to attain coordination...... on the efficient equilibrium, we consider sunspots as a potential reason for coordination failure. We conduct an experiment with a three player 2x2x2 game in which coordination on the efficient equilibrium is easy and should normally occur. In the control session, we find almost perfect coordination on the payoff......-dominant equilibrium, but in the sunspot treatment, dis-coordination is frequent. Sunspots lead to significant inefficiency, and we conclude that sunspots can indeed cause coordination failure....

  3. Delocalized mixed-valence bi- and trinuclear complexes with short Cu-Cu bonds.

    Science.gov (United States)

    Yang, Lei; Powell, Douglas R; Klein, Eric L; Grohmann, Andreas; Houser, Robert P

    2007-08-20

    Two mixed-valence copper complexes were synthesized with ligands N-(2-pyridylmethyl)acetamide (Hpmac) and N,N'-(2-methyl-2-pyridylpropan-1,3-diyl)bis(acetamide) (H2pp(ac)2). Dimer [Cu2(pmac)2]OTf and trimer [Cu3(pp(ac)2)2].NaOTf both contain fully delocalized, mixed-valence Cu(1.5)Cu(1.5) moieties.

  4. Trait Anxiety Is Associated with Negative Interpretations When Resolving Valence Ambiguity of Surprised Faces

    OpenAIRE

    Gewnhi Park; Vasey, Michael W.; Grace Kim; Dixie D Hu; Thayer, Julian F

    2016-01-01

    The current research examines whether trait anxiety is associated with negative interpretation bias when resolving valence ambiguity of surprised faces. To further isolate the neuro-cognitive mechanism, we presented angry, happy, and surprised faces at broad, high, and low spatial frequency and asked participants to determine the valence of each face. High trait anxiety was associated with more negative interpretations of broad spatial frequency (i.e., intact) surprised faces. However, the mo...

  5. Mixed-Valence Porphyrin π-Cation Radical Derivatives: Electrochemical Investigations.

    Science.gov (United States)

    Scheidt, W Robert; Buentello, Kristin E; Ehlinger, Noelle; Cinquantini, Arnaldo; Fontani, Marco; Laschi, Franco

    2008-05-05

    The electrochemistry of [Cu(OEP)] and [Ni(OEP)] are compared with the mixed-valence π-cations [Cu(OEP•/2)]2+and[Ni(OEP•/2)]2+. These electrochemical studies, carried out with cyclic voltametry and hydrodynamic voltametry, show that the mixed valence π-cations have distinct electrochemical properties, although the differences between the [M(OEP)](+/0) and [M(OEP•/2)]2+/0 processes are subtle.

  6. Modelling of Ion Transport in Solids with a General Bond Valence Based Force-Field

    OpenAIRE

    Adams, S.; R.P. Rao

    2010-01-01

    Empirical bond length - bond valence relations provide insight into the link between structure of and ion transport in solid electrolytes. Building on our earlier systematic adjustment of bond valence (BV) parameters to the bond softness, here we discuss how the squared BV mismatch can be linked to the absolute energy scale and used as a general Morse-type interaction potential for analyzing low-energy pathways in ion conducting solid or mixed conductors either by an energy landscape approach...

  7. Life changes and depressive symptoms: the effects of valence and amount of change

    OpenAIRE

    Bennik, Elise C.; Ormel, Johan; Oldehinkel, Albertine J.

    2013-01-01

    Background Only few studies have focused on the effects of positive life changes on depression, and the ones that did demonstrated inconsistent findings. The aim of the present study was to obtain a better understanding of the influence of positive life changes on depressive symptoms by decomposing life changes into a valence and an amount of change component. Methods Using hierarchical multiple regression, we examined the unique effects of valence (pleasantness/unpleasantness) and amount of ...

  8. Coordinating Work with Groupware

    DEFF Research Database (Denmark)

    Pors, Jens Kaaber; Simonsen, Jesper

    2003-01-01

    One important goal of employing groupware is to make possible complex collaboration between geographically distributed groups. This requires a dual transformation of both technology and work practice. The challenge is to re­duce the complexity of the coordination work by successfully inte­grating...

  9. Rockin' Readers Coordinator Handbook.

    Science.gov (United States)

    Alachua County Schools, Gainesville, FL.

    This coordinator's handbook describes the "Rockin' Readers" program, in which senior-citizen volunteers are matched with specifically targeted at-risk children (usually of kindergarten age or slightly older) in Alachua County, Florida, who tested below their peer group in language development and reading readiness skills. The handbook…

  10. Explicit Spin Coordinates

    CERN Document Server

    Hunter, G; Hunter, Geoffrey; Schlifer, Ian

    2005-01-01

    The recently established existence of spherical harmonic functions, $Y_\\ell^{m}(\\theta,\\phi)$ for half-odd-integer values of $\\ell$ and $m$, allows for the introduction into quantum chemistry of explicit electron spin-coordinates; i.e. spherical polar angles $\\theta_s, \\phi_s$, that specify the orientation of the spin angular momentum vector in space. In this coordinate representation the spin angular momentum operators, $S^2, S_z$, are represented by the usual differential operators in spherical polar coordinates (commonly used for $L^2, L_z$), and their electron-spin eigenfunctions are $\\sqrt{\\sin\\theta_s} \\exp(\\pm\\phi_s/2)$. This eigenfunction representation has the pedagogical advantage over the abstract spin eigenfunctions, $\\alpha, \\beta,$ that ``integration over spin coordinates'' is a true integration (over the angles $\\theta_s, \\phi_s$). In addition they facilitate construction of many electron wavefunctions in which the electron spins are neither parallel nor antiparallel, but inclined at an interme...

  11. Equilibria with Coordination Failures

    NARCIS (Netherlands)

    Herings, P.J.J.; van der Laan, G.; Talman, A.J.J.

    2004-01-01

    This paper extends the recent literature on equilibria with coordination failures to arbitrary convex sets of admissible prices.We introduce a new equilibrium concept, called quantity constrained equilibrium (QCE), giving a uni.ed treatment to all cases considered in the literature so far.At a QCE

  12. Block coordination copolymers

    Science.gov (United States)

    Koh, Kyoung Moo; Wong-Foy, Antek G; Matzger, Adam J; Benin, Annabelle I; Willis, Richard R

    2012-11-13

    The present invention provides compositions of crystalline coordination copolymers wherein multiple organic molecules are assembled to produce porous framework materials with layered or core-shell structures. These materials are synthesized by sequential growth techniques such as the seed growth technique. In addition, the invention provides a simple procedure for controlling functionality.

  13. A general valence asymmetry in similarity: Good is more alike than bad.

    Science.gov (United States)

    Koch, Alex; Alves, Hans; Krüger, Tobias; Unkelbach, Christian

    2016-08-01

    The density hypothesis (Unkelbach, Fiedler, Bayer, Stegmüller, & Danner, 2008) claims a general higher similarity of positive information to other positive information compared with the similarity of negative information to other negative information. This similarity asymmetry might explain valence asymmetries on all levels of cognitive processing. The available empirical evidence for this general valence asymmetry in similarity suffers from a lack of direct tests, low representativeness, and possible confounding variables (e.g., differential valence intensity, frequency, familiarity, or concreteness of positive and negative stimuli). To address these problems, Study 1 first validated the spatial arrangement method (SpAM) as a similarity measure. Using SpAM, Studies 2-6 found the proposed valence asymmetry in large, representative samples of self- and other-generated words (Studies 2a/2b), for words of consensual and idiosyncratic valence (Study 3), for words from 1 and many independent information sources (Study 4), for real-life experiences (Study 5), and for large data sets of verbal (i.e., ∼14,000 words reported by Warriner, Kuperman, & Brysbaert, 2013) and visual information (i.e., ∼1,000 pictures reported in the IAPS; Lang, Bradley, & Cuthbert, 2005; Study 6). Together, these data support a general valence asymmetry in similarity, namely that good is more alike than bad. (PsycINFO Database Record

  14. Global Coordinate System

    Science.gov (United States)

    1985-02-01

    Time in hours at Oh UT is GAST (hours) = GMST + E (41) GAST in radians is GASTo (radians) = GAST (hours) L (42) The angle e required for transforming...inertial coordinates to ECEF is- 6(radians) GASTo + 6.3003880.99 (ti - th) (43) o ~ooUT Mod ( E 27) where St.i - tohLjT = (JD -2.4 106). (JDOE -2.4 x

  15. International Monetary Policy Coordination

    OpenAIRE

    Carlberg, Michael

    2005-01-01

    This paper studies the international coordination of monetary policies in the world economy. It carefully discusses the process of policy competition and the structure of policy cooperation. As to policy competition, the focus is on monetary competition between Europe and America. Similarly, as to policy cooperation, the focus is on monetary cooperation between Europe and America. The spillover effects of monetary policy are negative. The policy targets are price stability and full employment.

  16. Global coordination: weighted voting

    Directory of Open Access Journals (Sweden)

    Jan-Erik Lane

    2014-03-01

    Full Text Available In order to halt the depletion of global ecological capital, a number of different kinds of meetings between Governments of countries in the world has been scheduled. The need for global coordination of environmental policies has become ever more obvious, supported by more and more evidence of the running down of ecological capital. But there are no formal or binding arrangements in sight, as global environmental coordination suffers from high transaction costs (qualitative voting. The CO2 equivalent emissions, resulting in global warming, are driven by the unstoppable economic expansion in the global market economy, employing mainly fossil fuel generated energy, although at the same time lifting sharply the GDP per capita of several emerging countries. Only global environmental coordination on the successful model of the World Band and the IMF (quantitative voting can stem the rising emissions numbers and stop further environmental degradation. However, the system of weighted voting in the WB and the IMF must be reformed by reducing the excessive voting power disparities, for instance by reducing all member country votes by the cube root expression.

  17. Universal mechatronics coordinator

    Science.gov (United States)

    Muir, Patrick F.

    1999-11-01

    Mechatronic systems incorporate multiple actuators and sensor which must be properly coordinated to achieve the desired system functionality. Many mechatronic systems are designed as one-of-a-kind custom projects without consideration for facilitating future system or alterations and extensions to the current syste. Thus, subsequent changes to the system are slow, different, and costly. It has become apparent that manufacturing processes, and thus the mechatronics which embody them, need to be agile in order to more quickly and easily respond to changing customer demands or market pressures. To achieve agility, both the hardware and software of the system need to be designed such that the creation of new system and the alteration and extension of current system is fast and easy. This paper describes the design of a Universal Mechatronics Coordinator (UMC) which facilitates agile setup and changeover of coordination software for mechatronic systems. The UMC is capable of sequencing continuous and discrete actions that are programmed as stimulus-response pairs, as state machines, or a combination of the two. It facilitates the modular, reusable programing of continuous actions such as servo control algorithms, data collection code, and safety checking routines; and discrete actions such as reporting achieved states, and turning on/off binary devices. The UMC has been applied to the control of a z- theta assembly robot for the Minifactory project and is applicable to a spectrum of widely differing mechatronic systems.

  18. Improving Project Manufacturing Coordination

    Directory of Open Access Journals (Sweden)

    Korpivaara Ville

    2014-09-01

    Full Text Available The objective of this research is to develop firms’ project manufacturing coordination. The development will be made by centralizing the manufacturing information flows in one system. To be able to centralize information, a deep user need assessment is required. After user needs have been identified, the existing system will be developed to match these needs. The theoretical background is achieved through exploring the literature of project manufacturing, development project success factors and different frameworks and tools for development project execution. The focus of this research is rather in customer need assessment than in system’s technical expertise. To ensure the deep understanding of customer needs this study is executed by action research method. As a result of this research the information system for project manufacturing coordination was developed to respond revealed needs of the stakeholders. The new system improves the quality of the manufacturing information, eliminates waste in manufacturing coordination processes and offers a better visibility to the project manufacturing. Hence it provides a solid base for the further development of project manufacturing.

  19. Redundant internal coordinates, compliance constants and non-bonded interactions - some new insights

    Indian Academy of Sciences (India)

    Moumita Majumder; Sadasivam Manogaran

    2013-01-01

    A long standing problem in normal mode analysis is identifying the right internal coordinates given only the cartesian coordinates, the masses of the atoms and the cartesian force constants without using any other additional chemical information. A possible solution is suggested here as drawing the normal modes obtained from the mass weighted cartesian force constant matrix and identifying the correct bonds and angles from the normal mode pictures. If chosen properly, the internal coordinates will have minimum mixing in the normal mode representation. This can in principle lead to an automation algorithm. A complete basis of internal coordinates is defined as the minimum number of valence internal coordinates that describe all the normal modes as completely as possible. It was shown in the literature that the relaxed force constants could be used as a measure of bond order in all atom-atom distance coordinates. Some of the bonded and non-bonded atom pairs can have similar values of the relaxed force constants and hence to use the relaxed force constant as a measure of bond order we need to separate the bonded pairs from the non-bonded ones. This needs extra chemical information of which pairs are bonded. The new definition of complete basis of non-redundant valence internal coordinates helps to identify the bonded pairs effectively without extra information. The hydrogen bonded water clusters (H2O), n = 2-6, methane dimer and methane-water complex are used as examples to verify that the relaxed force constants of bonded pairs are indeed a measure of bond order.

  20. Memory effects of sleep, emotional valence, arousal and novelty in children.

    Science.gov (United States)

    Vermeulen, Marije C M; van der Heijden, Kristiaan B; Benjamins, Jeroen S; Swaab, Hanna; van Someren, Eus J W

    2017-03-02

    Effectiveness of memory consolidation is determined by multiple factors, including sleep after learning, emotional valence, arousal and novelty. Few studies investigated how the effect of sleep compares with (and interacts with) these other factors, of which virtually none are in children. The present study did so by repeated assessment of declarative memory in 386 children (45% boys) aged 9-11 years through an online word-pair task. Children were randomly assigned to either a morning or evening learning session of 30 unrelated word-pairs with positive, neutral or negative valenced cues and neutral targets. After immediately assessing baseline recognition, delayed recognition was recorded either 12 or 24 h later, resulting in four different assessment schedules. One week later, the procedure was repeated with exactly the same word-pairs to evaluate whether effects differed for relearning versus original novel learning. Mixed-effect logistic regression models were used to evaluate how the probability of correct recognition was affected by sleep, valence, arousal, novelty and their interactions. Both immediate and delayed recognition were worse for pairs with negatively valenced or less arousing cue words. Relearning improved immediate and delayed word-pair recognition. In contrast to these effects, sleep did not affect recognition, nor did sleep moderate the effects of arousal, valence and novelty. The findings suggest a robust inclination of children to specifically forget the pairing of words to negatively valenced cue words. In agreement with a recent meta-analysis, children seem to depend less on sleep for the consolidation of information than has been reported for adults, irrespective of the emotional valence, arousal and novelty of word-pairs.

  1. Valence Virtual Orbitals: An Unambiguous ab Initio Quantification of the LUMO Concept.

    Science.gov (United States)

    Schmidt, Michael W; Hull, Emily A; Windus, Theresa L

    2015-10-15

    Many chemical concepts hinge on the notion of an orbital called the lowest unoccupied molecular orbital, or LUMO. This hypothetical orbital and the much more concrete highest occupied molecular orbital (HOMO) constitute the two "frontier orbitals", which rationalize a great deal of chemistry. A viable LUMO candidate should have a sensible energy value, a realistic shape with amplitude on those atoms where electron attachment or reduction or excitation processes occur, and often an antibonding correspondence to one of the highest occupied MOs. Unfortunately, today's quantum chemistry calculations do not yield useful empty orbitals. Instead, the empty canonical orbitals form a large sea of orbitals, where the interesting valence antibonds are scrambled with the basis set's polarization and diffuse augmentations. The LUMO is thus lost within a continuum associated with a detached electron, as well as many Rydberg excited states. A suitable alternative to the canonical orbitals is proposed, namely, the valence virtual orbitals. VVOs are found by a simple algorithm based on singular value decomposition, which allows for the extraction of all valence-like orbitals from the large empty canonical orbital space. VVOs are found to be nearly independent of the working basis set. The utility of VVOs is demonstrated for construction of qualitative MO diagrams, for prediction of valence excited states, and as starting orbitals for more sophisticated calculations. This suggests that VVOs are a suitable realization of the LUMO, LUMO + 1, ... VVO generation requires no expert knowledge, as the number of VVOs sought is found by counting s-block atoms as having only a valence s orbital, transition metals as having valence s and d, and main group atoms as being valence s and p elements. Closed shell, open shell, or multireference wave functions and elements up to xenon may be used in the present program.

  2. Experimental Constraints on the Partitioning and Valence of V and Cr in Garnet and Coexisting Glass

    Science.gov (United States)

    Righter, K.; Sutton, S.; Berthet, S.; Newville, M.

    2008-01-01

    A series of experiments with garnet and coexisting melt have been carried out across a range of oxygen fugacities (near hematite-magnetite (HM) to below the iron-wustite (IW) buffers) at 1.7 GPa to study the partitioning and valence of Cr and V in both phases. Experiments were carried out in a non end loaded piston cylinder apparatus, and the run products were analyzed with electron microprobe and xray absorption near edge structure (XANES) analysis at beamline 13-ID at the Advanced Photon Source of Argonne National Lab. The valence of vanadium and chromium were determined using the position and intensity of the Ka pre-edge peaks, calibrated on a series of Cr and Vbearing standard glasses. This technique has been applied to V and Cr in glasses and V in spinels previously, and in these isotropic phases there are no orientational effects on the XANES spectra (Righter et al., 2006, Amer. Mineral. 91, 1643-1656). We also now demonstrate this to be true for V and Cr in garnet. Also, previous work has shown that V has a higher valence in the glass (or melt) than in the coexisting spinel. This is also true for V in garnet-glass pairs in this study. Vanadium valence in garnets varies from 2.7 below the IW buffer to 3.7 near HM, and for coexisting glass it varies from 3.2 to 4.3. Vanadium valence measured in some natural garnets from mantle localities indicates V in the more reduced range at 2.5. Comparisons will be made between fO2 estimated from V valence and other methods for garnet-bearing mantle samples. In contrast, Cr valence measured in garnet and coexisting glass for all experimental and natural samples is 2.9- 3.0, suggesting that the valence of Cr does not vary within either phase across a large fO2 range. These results demonstrate that while V varies from 2+ to 3+ to 4+ in garnet-melt systems, Cr does not, and this will ultimately affect the partitioning behavior of these two elements in natural systems. Garnet/melt D(Cr) are between 12 and 17 across this range

  3. Symmetric two-coordinate photodiode

    Directory of Open Access Journals (Sweden)

    Dobrovolskiy Yu. G.

    2008-12-01

    Full Text Available The two-coordinate photodiode is developed and explored on the longitudinal photoeffect, which allows to get the coordinate descriptions symmetric on the steepness and longitudinal resistance great exactness. It was shown, that the best type of the coordinate description is observed in the case of scanning by the optical probe on the central part of the photosensitive element. The ways of improvement of steepness and linear of its coordinate description were analyzed.

  4. Invariant Manifolds and Collective Coordinates

    CERN Document Server

    Papenbrock, T

    2001-01-01

    We introduce suitable coordinate systems for interacting many-body systems with invariant manifolds. These are Cartesian in coordinate and momentum space and chosen such that several components are identically zero for motion on the invariant manifold. In this sense these coordinates are collective. We make a connection to Zickendraht's collective coordinates and present certain configurations of few-body systems where rotations and vibrations decouple from single-particle motion. These configurations do not depend on details of the interaction.

  5. Vibrational spectra, normal coordinate treatment and simulation of the vibrational spectra of piperazine glyoxime and its Co(III) complex

    Science.gov (United States)

    Özpozan, T.; Küçükusta, D.; Büyükmumcu, Z.

    2003-12-01

    Newly synthesized Co(III) complexes of piperazine glyoxime (PGO) are examined from the vibrational spectroscopy point of view. A complete interpretation of the vibrational spectra of both the ligand and the complex has been carried out on the basis of normal coordinate analysis. A valence force field has been developed for both of the compounds. The vibrational spectra of the compounds are simulated by a visual basic program prepared to run on an MS Excel data sheet.

  6. The effective valence shell Hamiltonian calculations of spin-orbit splittings in small diatomic hydrides.

    Science.gov (United States)

    Chang, Ye Won; Sun, Hosung

    2008-12-18

    Recently, the size extensive, ab initio effective valence shell Hamiltonian method for spin-orbit coupling has been suggested. In essence, this effective Hamiltonian method is equivalent to the quasidegenerate perturbation theory. But the difference lies in transforming the original Hamiltonian into an effective Hamiltonian acting within a relatively small valence in the effective valence shell Hamiltonian method. One advantage of the method is that the spin-orbit coupling energies of all valence states for both the neutral species and its ions are simultaneously determined with a similar accuracy from a single computation of the effective spin-orbit coupling operator. Thus, fine structure splittings are predicted for a number of states of each system for which neither experiment nor theory is available. To assess the accuracy of the effective Hamiltonian method more extensively, test calculations are performed for the spin-orbit splittings in the valence states of small diatomic hydrides and their ions. The calculated spin-orbit splittings are generally in good agreement with experiments and with other ab initio computations.

  7. Verbal instructions targeting valence alter negative conditional stimulus evaluations (but do not affect reinstatement rates).

    Science.gov (United States)

    Luck, Camilla C; Lipp, Ottmar V

    2017-01-31

    Negative conditional stimulus (CS) valence acquired during fear conditioning may enhance fear relapse and is difficult to remove as it extinguishes slowly and does not respond to the instruction that unconditional stimulus (US) presentations will cease. We examined whether instructions targeting CS valence would be more effective. In Experiment 1, an image of one person (CS+) was paired with an aversive US, while another (CS-) was presented alone. After acquisition, participants were given positive information about the CS+ poser and negative information about the CS- poser. Instructions reversed the pattern of differential CS valence present during acquisition and eliminated differential electrodermal responding. In Experiment 2, we compared positive and negative CS revaluation by providing positive/negative information about the CS+ and neutral information about CS-. After positive revaluation, differential valence was removed and differential electrodermal responding remained intact. After negative revaluation, differential valence was strengthened and differential electrodermal responding was eliminated. Unexpectedly, the instructions did not affect the reinstatement of differential electrodermal responding.

  8. Negative valence can evoke a liberal response bias in syllogistic reasoning.

    Science.gov (United States)

    Vartanian, Oshin; Nakashima, Ann; Bouak, Fethi; Smith, Ingrid; Baranski, Joseph V; Cheung, Bob

    2013-03-01

    Recently, studies have demonstrated that negative valence reduces the magnitude of the belief-bias effect in syllogistic reasoning. This effect has been localized in the reasoning stage, in the form of increased deliberation on trials where validity and conclusion believability are incongruent. Here, using signal detection theory, we show that the attenuation of belief bias observed when valence was negative can also be evoked by a liberal response bias at the decision stage. Indeed, when valence was negative participants adopted a more liberal criterion for judging syllogisms as "valid," and were overconfident in their judgments. They also displayed less sensitivity in distinguishing between valid and invalid syllogisms. Our findings dovetail with recent evidence from memory research suggesting that negative valence can evoke a liberal response bias without improving performance. Our novel contribution is the demonstration that the attenuating effect of negative valence on belief bias can take multiples routes--by influencing the decision stage as was the case here, the reasoning stage as has been demonstrated elsewhere, and potentially both stages.

  9. The impact of intonation and valence on objective and subjective attention capture by auditory alarms.

    Science.gov (United States)

    Ljungberg, Jessica K; Parmentier, Fabrice

    2012-10-01

    The objective was to study the involuntary capture of attention by spoken words varying in intonation and valence. In studies of verbal alarms, the propensity of alarms to capture attention has been primarily assessed with the use of subjective ratings of their perceived urgency. Past studies suggest that such ratings vary with the alarms' spoken urgency and content. We measured attention capture by spoken words varying in valence (negative vs. neutral) and intonation (urgently vs. nonurgently spoken) through subjective ratings and behavioral measures. The key behavioral measure was the response latency to visual stimuli in the presence of spoken words breaking away from the periodical repetition of a tone. The results showed that all words captured attention relative to a baseline standard tone but that this effect was partly counteracted by a relative speeding of responses for urgently compared with nonurgently spoken words. Word valence did not affect behavioral performance. Rating data showed that both intonation and valence increased significantly perceived urgency and attention grabbing without any interaction. The data suggest a congruency between subjective ratings and behavioral performance with respect to spoken intonation but not valence. This study demonstrates the usefulness and feasibility of objective measures of attention capture to help design efficient alarm systems.

  10. The temporal dynamics of reversal learning: P3 amplitude predicts valence-specific behavioral adjustment.

    Science.gov (United States)

    Donaldson, Kayla R; Ait Oumeziane, Belel; Hélie, Sebastien; Foti, Dan

    2016-07-01

    Adapting behavior to dynamic stimulus-reward contingences is a core feature of reversal learning and a capacity thought to be critical to socio-emotional behavior. Impairment in reversal learning has been linked to multiple psychiatric outcomes, including depression, Parkinson's disorder, and substance abuse. A recent influential study introduced an innovative laboratory reversal-learning paradigm capable of disentangling the roles of feedback valence and expectancy. Here, we sought to use this paradigm in order to examine the time-course of reward and punishment learning using event-related potentials among a large, representative sample (N=101). Three distinct phases of processing were examined: initial feedback evaluation (reward positivity, or RewP), allocation of attention (P3), and sustained processing (late positive potential, or LPP). Results indicate a differential pattern of valence and expectancy across these processing stages: the RewP was uniquely related to valence (i.e., positive vs. negative feedback), the P3 was uniquely associated with expectancy (i.e., unexpected vs. expected feedback), and the LPP was sensitive to both valence and expectancy (i.e., main effects of each, but no interaction). The link between ERP amplitudes and behavioral performance was strongest for the P3, and this association was valence-specific. Overall, these findings highlight the potential utility of the P3 as a neural marker for feedback processing in reversal-based learning and establish a foundation for future research in clinical populations.

  11. Differential Activation of Amygdala Arc Expression By Positive and Negatively Valenced Emotional Learning Conditions

    Directory of Open Access Journals (Sweden)

    Erica eYoung

    2013-12-01

    Full Text Available Norepinephrine is released in the amygdala following negatively arousing learning conditions. This event initiates a cascade of changes including the transcription of activity-regulated cytoskeleton-associated protein (Arc expression, an early-immediate gene associated with memory encoding. Recent evidence suggests that the valence of emotionally laden encounters may generate lateralized, as opposed to symmetric release of this transmitter in the right or left amygdala. It is currently not clear if valence-induced patterns of selective norepinephrine output across hemispheres are also reproduced in downstream pathways of cellular signaling necessary for memory formation. This question was addressed by determining if Arc expression is differentially distributed across the right and left amygdala following exposure to positively or negatively valenced learning conditions respectively. Male Sprague Dawley rats were randomly assigned to groups exposed to the Homecage only, 5 auditory tones only, or 5 auditory tones paired with footshock (0.35mA during Pavlovian fear conditioning. Western blot analysis revealed that Arc expression in the right amygdala was elevated significantly above that observed in the left amygdala 60 and 90 minutes following fear conditioning. Similarly, subjects exposed to a a negatively valenced outcome consisting of an unexpected reduction in food rewards showed a greater level of Arc expression in only the right, but not left basolateral amygdala. Presenting a positively valenced event involving an unexpected increase in food reward magnitude following bar pressing, resulted in significantly greater Arc expression in the left, but not right basolateral amygdala (p

  12. Music, Emotion and Time Perception: The influence of subjective emotional valence and arousal?

    Directory of Open Access Journals (Sweden)

    SYLVIE eDROIT-VOLET

    2013-07-01

    Full Text Available The present study used a temporal bisection task with short (< 2 s and long (> 2 s stimulus durations to investigate the effect on time estimation of several musical parameters associated with emotional changes in affective valence and arousal. In order to manipulate the positive and negative valence of music, Experiments 1 and 2 contrasted the effect of musical structure with pieces played normally and backwards, which were judged to be pleasant and unpleasant, respectively. This effect of valence was combined with a subjective arousal effect by changing the tempo of the musical pieces (fast vs. slow (Experiment 1 or their instrumentation (orchestral vs. piano pieces. The musical pieces were indeed judged more arousing with a fast than with a slow tempo and with an orchestral than with a piano timbre. In Experiment 3, affective valence was also tested by contrasting the effect of tonal (pleasant versus atonal (unpleasant versions of the same musical pieces. The results showed that the effect of tempo in music, associated with a subjective arousal effect, was the major factor that produced time distortions with time being judged longer for fast than for slow tempi. When the tempo was held constant, no significant effect of timbre on the time judgment was found although the orchestral music was judged to be more arousing than the piano music. Nevertheless, emotional valence did modulate the tempo effect on time perception, the pleasant music being judged shorter than the unpleasant music.

  13. Rare beryllium icosahedra in the intermediate valence compound CeBe13.

    Science.gov (United States)

    Wilson, Zakiya S; Macaluso, Robin T; Bauer, E D; Smith, J L; Thompson, J D; Fisk, Z; Stanley, George G; Chan, Julia Y

    2004-11-01

    Single-crystal X-ray diffraction experiments show that the Be atoms in CeBe13 form a Be12 icosahedra, which is a very unusual structural feature due, in part, to the remarkably low valence electron count of Be. Magnetization studies show that CeBe13 displays intermediate valence behavior, in which valence fluctuations between the Ce 4f0 and 4f1 states give rise to enhanced electronic specific heat and magnetic susceptibility. Calculations using ab initio theory were used to determine the electronic structure and bonding and to give insight into the relationship between the crystal structure, the bonding, and the intermediate valence behavior of CeBe13. The hybridization between the localized f electrons and the conduction electrons is responsible for the large values of the electronic specific heat coefficient (gamma approximately 100 mJ/mol K2) and magnetic susceptibility (chi approximately 1 x 10-3 emu/mol), which is in marked contrast to those of ordinary metals that have gamma approximately 1 mJ/mol K2 and chi approximately 1 x 10-5 emu/mol values. The magnetic susceptibility, chi = M/H versus T, of a single crystal of CeBe13 exhibits a broad maximum at Tmax approximately 130 K and is typical of intermediate valence systems with an unusually large energy scale (Kondo), TK approximately 500 K.

  14. The influence of valence and arousal on reasoning: Affective priming in the semantic verification task

    Directory of Open Access Journals (Sweden)

    Orlić Ana

    2014-01-01

    Full Text Available The aim of the present study was to examine the effects of affective valence and arousal on the reasoning process. Reasoning was measured using a semantic verification task and the influence of valence and arousal was tracked using the affective priming paradigm. Primes were photographs varied on two dimensions - emotional valence (positive, neutral, negative and arousal (high, low. Forty-nine psychology students participated in the experiment. Results showed that reaction time needed for semantic verification was significantly faster for positive-high arousing in comparison to positive-low arousing condition and for neutral high arousing in comparison to neutral-low arousing condition, but there were no significant differences in negative low and high arousing conditions. Also, significant differences were found among all three valences in high arousing conditions and there were no such differences in low arousing conditions. These results reveal the importance of both arousal and valence in the research on the influence of emotions on the reasoning process. [Projekat Ministarstva nauke Republike Srbije, br. 179033

  15. Coordination Processes in International Organisations

    DEFF Research Database (Denmark)

    Nedergaard, Peter

    2008-01-01

    to coordinate relatively elaborate agreements due to the strength of its coordination as far as professional or technical and political activities (excepting the ILO budget) are concerned. In other more clear-cut or 'simple' policy areas such as the ILO budget, the EU coordination is weak: this contrast...

  16. Signatures of distinct impurity configurations in atomic-resolution valence electron-energy-loss spectroscopy: Application to graphene

    Science.gov (United States)

    Kapetanakis, Myron D.; Oxley, Mark P.; Zhou, Wu; Pennycook, Stephen J.; Idrobo, Juan-Carlos; Pantelides, Sokrates T.

    2016-10-01

    The detection and identification of impurities and other point defects in materials is a challenging task. Signatures for point defects are typically obtained using spectroscopies without spatial resolution. Here we demonstrate the power of valence electron-energy-loss spectroscopy (VEELS) in an aberration-corrected scanning transmission-electron microscope (STEM) to provide energy-resolved and atomically resolved maps of electronic excitations of individual impurities which, combined with theoretical simulations, yield unique signatures of distinct bonding configurations of impurities. We report VEELS maps for isolated Si impurities in graphene, which are known to exist in two distinct configurations. We also report simulations of the maps, based on density functional theory and dynamical scattering theory, which agree with and provide direct interpretation of observed features. We show that theoretical VEELS maps exhibit distinct and unambiguous signatures for the threefold- and fourfold-coordinated configurations of Si impurities in different energy-loss windows, corresponding to impurity-induced bound states, resonances, and antiresonances. With the advent of new monochromators and detectors with high energy resolution and low signal-to-noise ratio, the present work ushers an atomically resolved STEM-based spectroscopy of individual impurities as an alternative to conventional spectroscopies for probing impurities and defects.

  17. Photodissociation of carbon dioxide in singlet valence electronic states. II. Five state absorption spectrum and vibronic assignment

    Science.gov (United States)

    Grebenshchikov, Sergy Yu.

    2013-06-01

    The absorption spectrum of CO2 in the wavelength range 120-160 nm is analyzed by means of quantum mechanical calculations performed using vibronically coupled potential energy surfaces of five singlet valence electronic states and the coordinate dependent transition dipole moment vectors. The thermally averaged spectrum, calculated for T = 190 K via Boltzmann averaging of optical transitions from many initial rotational states, accurately reproduces the experimental spectral envelope, consisting of a low and a high energy band, the positions of the absorption maxima, their FWHMs, peak intensities, and frequencies of diffuse structures in each band. Contributions of the vibronic interactions due to Renner-Teller coupling, conical intersections, and the Herzberg-Teller effect are isolated and the calculated bands are assigned in terms of adiabatic electronic states. Finally, diffuse structures in the calculated bands are vibronically assigned using wave functions of the underlying resonance states. It is demonstrated that the main progressions in the high energy band correspond to consecutive excitations of the pseudorotational motion along the closed loop of the CI seam, and progressions differ in the number of nodes along the radial mode perpendicular to the closed seam. Irregularity of the diffuse peaks in the low energy band is interpreted as a manifestation of the carbene-type "cyclic" OCO minimum.

  18. Manganese L-edge X-ray absorption spectroscopy of manganese catalase from Lactobacillus plantarum and mixed valence manganese complexes

    Energy Technology Data Exchange (ETDEWEB)

    Grush, M.M.; Chen, J.; George, S.J. [Univ. of California, Davis, CA (United States)] [and others

    1996-01-10

    The first Mn L-edge absorption spectra of a Mn metalloprotein are presented in this paper. Both reduced and superoxidized Mn catalase have been examined by fluorescence-detected soft X-ray absorption spectroscopy, and their Mn L-edge spectra are dramatically different. The spectrum of reduced Mn(II)Mn(II) catalase has been interpreted by ligand field atomic multiplet calculations and by comparison to model compound spectra. The analysis finds a 10 Dq value of nearly 1.1 eV, consistent with coordination by predominately nitrogen and oxygen donor ligands. For interpretation of mixed valence Mn spectra, an empirical simulation procedure based on the addition of homovalent model compound spectra has been developed and was tested on a variety of Mn complexes and superoxidized Mn catalase. This routine was also used to determine the oxidation state composition of the Mn in [Ba{sub 8}Na{sub 2}ClMn{sub 16}(OH){sub 8}(CO{sub 3}){sub 4}L{sub 8}] .53 H{sub 2}O (L=1,3-diamino-2-hydroxypropane-N,N,N`N`-tetraacetic acid). 27 refs., 6 figs.

  19. Mixed europium valence in Eu0.937Ba8[BN2]6 - Structure and spectroscopic behavior

    Science.gov (United States)

    Dierkes, Tobias; Seidel, Stefan; Benndorf, Christopher; Heletta, Lukas; de Oliveira Junior, Marcos; Holtkamp, Michael; Karst, Uwe; Block, Theresa; Jüstel, Thomas; Eckert, Hellmut; Pöttgen, Rainer

    2017-08-01

    Polycrystalline samples of Sr0.95Eu0.05Ba8[BN2]6 and Eu0.937Ba8[BN2]6 were synthesized via conventional solid-state reaction from the binary precursor compounds Sr3N2, EuN, Ba3N2 and BN at 1000 °C. The structure of Eu0.937Ba8[BN2]6 was refined from single crystal X-ray diffractometer data: Eu0.937Ba8[BN2]6 type, Fd 3 barm, a = 1594.54(9) pm, wR2 = 0.0654, 380 F2 values and 23 variables. The 8a europium site shows an occupancy of only 93.7(9) % suggesting partial oxidation of europium to fulfil an electron-precise description, i. e. EuII0.81EuIII0.13Ba8[BN2]6. The mixed europium valence was confirmed by magnetic susceptibility measurements (reduced magnetic moment of 7.28 μB per europium atom) and 151Eu Mössbauer spectroscopy (EuII: EuIII = 82: 18). The nitridoborate anions are coordinated by slightly distorted, mono-capped (europium) square prisms formed by the barium atoms. All metal cations are hexa-coordinated by nitrogen atoms. The EPR spectra of EuxSr1-xBa8[BN2]6 samples (0.001 ≤ x ≤ 0.01) suggest close to cubic local symmetry of the Eu2+ dopant ions and reveal some highly unusual features: Magnetic hyperfine splitting is only observed with one of the Eu nuclear isotopes, and the coupling constant of 243.6 MHz is extremely large compared to values (90-100 MHz) typically observed in the literature for Eu2+ doped crystalline materials.

  20. Work Coordination Engine

    Science.gov (United States)

    Zendejas, Silvino; Bui, Tung; Bui, Bach; Malhotra, Shantanu; Chen, Fannie; Kim, Rachel; Allen, Christopher; Luong, Ivy; Chang, George; Sadaqathulla, Syed

    2009-01-01

    The Work Coordination Engine (WCE) is a Java application integrated into the Service Management Database (SMDB), which coordinates the dispatching and monitoring of a work order system. WCE de-queues work orders from SMDB and orchestrates the dispatching of work to a registered set of software worker applications distributed over a set of local, or remote, heterogeneous computing systems. WCE monitors the execution of work orders once dispatched, and accepts the results of the work order by storing to the SMDB persistent store. The software leverages the use of a relational database, Java Messaging System (JMS), and Web Services using Simple Object Access Protocol (SOAP) technologies to implement an efficient work-order dispatching mechanism capable of coordinating the work of multiple computer servers on various platforms working concurrently on different, or similar, types of data or algorithmic processing. Existing (legacy) applications can be wrapped with a proxy object so that no changes to the application are needed to make them available for integration into the work order system as "workers." WCE automatically reschedules work orders that fail to be executed by one server to a different server if available. From initiation to completion, the system manages the execution state of work orders and workers via a well-defined set of events, states, and actions. It allows for configurable work-order execution timeouts by work-order type. This innovation eliminates a current processing bottleneck by providing a highly scalable, distributed work-order system used to quickly generate products needed by the Deep Space Network (DSN) to support space flight operations. WCE is driven by asynchronous messages delivered via JMS indicating the availability of new work or workers. It runs completely unattended in support of the lights-out operations concept in the DSN.

  1. Effet de la valence émotionnelle sur la mémoire prospective au cours du vieillissement.

    OpenAIRE

    Blondelle, Geoffrey; Hainselin, Mathieu; Gounden, Yannick; Heurley, Laurent; Voisin, Hélène; Bressous, Estelle; Quaglino, Véronique

    2015-01-01

    International audience; Emotional valence can affect performance in prospective memory (PM), but its impact with regard to aging remains unknown. By using a task inspired from the Virtual Week, our study thus examined the effect of emotional valence on PM in three groups of participants: 28 young adults (18-30), 16 middle aged adults (40-55) and 25 older adults (65-80). The prospective memory task required the recalling of activities bearing different emotional valences (negative, neutral or ...

  2. Advice for Coordination

    DEFF Research Database (Denmark)

    Hankin, Chris; Nielson, Flemming; Nielson, Hanne Riis

    2008-01-01

    demanding than the closed joinpoints in more traditional aspect oriented languages like AspectJ. The usefulness of our approach is demonstrated by mechanisms for discretionary and mandatory access control policies, as usually expressed by reference monitors, as well as mechanisms for logging actions.......We show how to extend a coordination language with support for aspect oriented programming. The main challenge is how to properly deal with the trapping of actions before the actual data have been bound to the formal parameters. This necessitates dealing with open joinpoints – which is more...

  3. Markov stochasticity coordinates

    Science.gov (United States)

    Eliazar, Iddo

    2017-01-01

    Markov dynamics constitute one of the most fundamental models of random motion between the states of a system of interest. Markov dynamics have diverse applications in many fields of science and engineering, and are particularly applicable in the context of random motion in networks. In this paper we present a two-dimensional gauging method of the randomness of Markov dynamics. The method-termed Markov Stochasticity Coordinates-is established, discussed, and exemplified. Also, the method is tweaked to quantify the stochasticity of the first-passage-times of Markov dynamics, and the socioeconomic equality and mobility in human societies.

  4. Mixed valency and site-preference chemistry for cerium and its compounds: A predictive density-functional theory study

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Aftab [Ames Laboratory; Johnson, Duane D. [Ames Laboratory

    2014-06-01

    Cerium and its technologically relevant compounds are examples of anomalous mixed valency, originating from two competing oxidation states—itinerant Ce4+ and localized Ce3+. Under applied stress, anomalous transitions are observed but not well understood. Here we treat mixed valency as an “alloy” problem involving two valences with competing and numerous site-occupancy configurations. We use density-functional theory with Hubbard U (i.e., DFT+U) to evaluate the effective valence and predict properties, including controlling the valence by pseudoternary alloying. For Ce and its compounds, such as (Ce,La)2(Fe,Co)14B permanent magnets, we find a stable mixed-valent α state near the spectroscopic value of νs=3.53. Ce valency in compounds depends on its steric volume and local chemistry. For La doping, Ce valency shifts towards γ-like Ce3+, as expected from steric volume; for Co doping, valency depends on local Ce-site chemistry and steric volume. Our approach captures the key origins of anomalous valency and site-preference chemistry in complex compounds.

  5. The role of valence focus and appraisal overlap in emotion differentiation.

    Science.gov (United States)

    Erbas, Yasemin; Ceulemans, Eva; Koval, Peter; Kuppens, Peter

    2015-06-01

    Emotion differentiation refers to the level of specificity with which people distinguish between their emotional states and is considered to play an important role for psychological well-being. Yet, not much is known about what characterizes people high or low in emotion differentiation and what underlies these differences. In 2 studies involving experience sampling (Studies 1-2) and lab based (Study 2) methods, we investigated how emotion differentiation is related to individual differences in valence focus and the overlap in appraisal patterns between emotions. In line with expectations, results showed that high levels of both positive and negative emotion differentiation are related to lower levels of valence focus and lower levels of appraisal overlap between emotions. These findings suggest that individuals who are low in emotion differentiation mainly emphasize the valence aspect of emotions while individuals who are high in emotion differentiation make stronger distinctions between emotions in terms of their underlying appraisal profiles. (c) 2015 APA, all rights reserved).

  6. Valence of self-cognitions: the positivity of individual self-statements.

    Science.gov (United States)

    Bromgard, Gregg D; Trafimow, David; Bromgard, Irina K

    2006-02-01

    Based on D. Trafimow, H. C. Triandis, and S. Goto's (1991) research on the distinction between the private, collective, and relational selves, the present authors explored the valence of each self. The authors administered to participants either a private self-prime, a collective self-prime, or a relational self-prime and then asked them to write 20 self-statements. The authors coded the statements for valence (positive, neutral, or negative) and self-statement type (individual, collective, or relational). The results indicated that the valence of individual self-statements were most positive when the collective self or the relational self was primed, indicating the possibility that positive illusions were exaggerated most in the context of other people.

  7. Children's spontaneous counterfactuals: The roles of valence, expectancy, and cognitive flexibility.

    Science.gov (United States)

    Guajardo, Nicole R; McNally, Lena F; Wright, Amanda

    2016-06-01

    The current set of studies examined whether 8- to 11-year-olds generate counterfactuals spontaneously and whether outcome valence and outcome expectancy affect counterfactual reasoning within this age group. The role of cognitive flexibility in such reasoning also was explored. In Study 1, relatively few children spontaneously generated counterfactuals, yet both outcome expectancy and outcome valence influenced counterfactual reasoning. In Study 2, the majority of children generated counterfactuals without an explicit prompt and outcome valence influenced reasoning. Cognitive flexibility accounted for unique variance in counterfactual reasoning. The findings suggest that in middle childhood children spontaneously engage in counterfactual reasoning and that some of the same factors influence counterfactual reasoning in childhood as in adulthood.

  8. The effects of age and emotional valence on recognition memory: an ex-Gaussian components analysis.

    Science.gov (United States)

    Moret-Tatay, Carmen; Moreno-Cid, Amparo; Argimon, Irani Iracema de Lima; Quarti Irigaray, Tatiana; Szczerbinski, Marcin; Murphy, Mike; Vázquez-Martínez, Andrea; Vázquez-Molina, Joan; Sáiz-Mauleón, Begoña; Navarro-Pardo, Esperanza; Fernández de Córdoba Castellá, Pedro

    2014-10-01

    The aim of this work was to study the effects of valence and age on visual image recognition memory. The International Affective Picture System (IAPS) battery was used, and response time data were analyzed using analysis of variance, as well as an ex-Gaussian fit method. Older participants were slower and more variable in their reaction times. Response times were longer for negative valence pictures, however this was statistically significant only for young participants. This suggests that negative emotional valence has a strong effect on recognition memory in young but not in old participants. The τ parameter, often related to attention in the literature, was smaller for young than old participants in an ex-Gaussian fit. Differences on the τ parameter might suggest poorer attentional performance in old participants.

  9. Reversing Stimulus Timing in Visual Conditioning Leads to Memories with Opposite Valence in Drosophila.

    Directory of Open Access Journals (Sweden)

    Katrin Vogt

    Full Text Available Animals need to associate different environmental stimuli with each other regardless of whether they temporally overlap or not. Drosophila melanogaster displays olfactory trace conditioning, where an odor is followed by electric shock reinforcement after a temporal gap, leading to conditioned odor avoidance. Reversing the stimulus timing in olfactory conditioning results in the reversal of memory valence such that an odor that follows shock is later on approached (i.e. relief conditioning. Here, we explored the effects of stimulus timing on memory in another sensory modality, using a visual conditioning paradigm. We found that flies form visual memories of opposite valence depending on stimulus timing and can associate a visual stimulus with reinforcement despite being presented with a temporal gap. These results suggest that associative memories with non-overlapping stimuli and the effect of stimulus timing on memory valence are shared across sensory modalities.

  10. Time-resolved imaging of purely valence-electron dynamics during a chemical reaction

    DEFF Research Database (Denmark)

    Hockett, Paul; Bisgaard, Christer Z.; Clarkin, Owen J.

    2011-01-01

    Chemical reactions are manifestations of the dynamics of molecular valence electrons and their couplings to atomic motions. Emerging methods in attosecond science can probe purely electronic dynamics in atomic and molecular systems(1-6). By contrast, time-resolved structural-dynamics methods......,17): in both cases, this sensitivity derives from the ionization-matrix element(18,19). Here we demonstrate a time-resolved molecular-frame photoelectron-angular-distribution (TRMFPAD) method for imaging the purely valence-electron dynamics during a chemical reaction. Specifically, the TRMFPADs measured during...... the non-adiabatic photodissociation of carbon disulphide demonstrate how the purely electronic rearrangements of the valence electrons can be projected from inherently coupled electronic-vibrational dynamics. Combined with ongoing efforts in molecular frame alignment(20) and orientation(21,22), TRMFPADs...

  11. fK /f{pi} in Full QCD with Domain Wall Valence Quarks

    Energy Technology Data Exchange (ETDEWEB)

    Silas Beane; Paulo Bedaque; Konstantinos Orginos; Martin Savage

    2007-05-01

    We compute the ratio of pseudoscalar decay constants f{sub K}/f{sub {pi}} using domain-wall valence quarks and rooted improved Kogut-Susskind sea quarks. By employing continuum chiral perturbation theory, we extract the Gasser-Leutwyler low-energy constant L{sub 5}, and extrapolate f{sub K}/f{sub {pi}} to the physical point. We find: f{sub K}/f{sub {pi}} = 1.218 {+-} 0.002{sub -0.024}{sup +0.011} where the first error is statistical and the second error is an estimate of the systematic due to chiral extrapolation and fitting procedures. This value agrees within the uncertainties with the determination by the MILC collaboration, calculated using Kogut-Susskind valence quarks, indicating that systematic errors arising from the choice of lattice valence quark are small.

  12. Physical properties and valence state of cerium in the filled skutterudite CePt₄Ge₁₂.

    Science.gov (United States)

    Gumeniuk, R; Kvashnina, K O; Schnelle, W; Nicklas, M; Borrmann, H; Rosner, H; Skourski, Y; Tsirlin, A A; Leithe-Jasper, A; Grin, Yu

    2011-11-23

    Electronic, magnetic, and transport properties of the filled platinum-germanium skutterudite CePt₄Ge₁₂ are investigated. High resolution x-ray absorption spectroscopy measurements at the cerium L(III) edge demonstrate that CePt₄Ge₁₂ in this compound has a temperature-independent valence close to three. However, magnetic susceptibility, thermopower, Hall effect, and electronic specific heat reveal a broad maximum at Tmax D 65-80 K, suggesting the presence of valence fluctuations. The Sommerfeld coefficient γ = 105 mJ mol⁻¹ K⁻², deduced from specific heat, indicates moderately enhanced band masses for CePt₄Ge₁₂. We discuss these findings and conclude that CePt₄Ge₁₂ represents a system at the border between intermediate valence (IV) and Kondo lattice behavior. In addition, the lattice specific heat and the thermal conductivity are discussed with respect to the vibrational dynamics of Ce in the [Pt₄Ge₁₂] framework.

  13. Emotion perception and functional outcome in schizophrenia: the importance of negative valence and fear.

    Science.gov (United States)

    Brittain, Philip J; Ffytche, Dominic H; Surguladze, Simon A

    2012-12-30

    A substantial body of work has demonstrated that persons with schizophrenia have a deficit in the perception of emotional stimuli. More recently this deficit has been linked to poor functional outcomes (FO) in this group. The current research investigated the perception of emotional stimuli in a group of 64 schizophrenia patients and 65 matched healthy controls. In the patient group, across two different emotion perception tasks and a social perception task, small deficits were found in the perception of negative, positive and neutrally valenced stimuli. Only the ability to perceive negative and neutrally valenced stimuli significantly correlated with a set of FO measures in the patients, with one task indicating these associations were strongest for the perception of fear. Subsequent regression modelling, controlling for the effects of symptomatology, demonstrated that for each of the three tasks, the measure of negative valence perception accounted for a similar but small amount (4%) of the variance seen in the functional status of the patients.

  14. Name-valence and physical attractiveness in Facebook: their compensatory effects on friendship acceptance.

    Science.gov (United States)

    Greitemeyer, Tobias; Kunz, Irene

    2013-01-01

    Name-valence and physical attractiveness have been shown to be associated with how people respond toward others, in that people judge and behave more positively toward individuals with positive names and individuals who are physically attractive. The present research examined whether Facebook users are more likely to accept friendship requests from other Facebook users with positive (relative to negative) names and who are physically attractive (relative to being moderately attractive). In fact, both name-valence and physical attractiveness affected friendship acceptance. Moreover, results revealed that name-valence can be compensated by physical attractiveness (and vice versa). Acceptance rates of requests from users with positive names who are moderately attractive, as well as requests from users with negative names who are attractive did not significantly differ from those with positive names who are attractive.

  15. Reactivity of seventeen- and nineteen-valence electron complexes in organometallic chemistry

    Science.gov (United States)

    Stiegman, Albert E.; Tyler, David R.

    1986-01-01

    A guideline to the reactivity of 17- and 19-valence electron species in organometallic chemistry is proposed which the authors believe will supersede all others. The thesis holds that the reactions of 17-electron metal radicals are associatively activated with reactions proceeding through a 19-valence electron species. The disparate reaction chemistry of the 17-electron metal radicals are unified in terms of this associative reaction pathway, and the intermediacy of 19-valence electron complexes in producing the observed products is discussed. It is suggested that related associatively activated pathways need to be considered in some reactions that are thought to occur by more conventional routes involving 16- and 18-electron intermediates. The basic reaction chemistry and electronic structures of these species are briefly discussed.

  16. Artificially induced valence of distractor words increases the effects of irrelevant speech on serial recall.

    Science.gov (United States)

    Buchner, Axel; Mehl, Bettina; Rothermund, Klaus; Wentura, Dirk

    2006-07-01

    In a game context, nonwords either were artificially associated with negative valence or were in some sense neutral or irrelevant. Subsequently, participants memorized target words in silence or while attempting to ignore the negatively valent, irrelevant, or neutral auditory distractor nonwords. The presence of distractor nonwords impaired recall performance, but negative distractor nonwords caused more disruption than neutral and irrelevant distractors, which did not differ in how much disruption they caused. These findings conceptually replicate earlier results showing disruption due to valence with natural language words and extend them by demonstrating that auditory features that may possibly be confounded with valence in natural language words cannot be the cause of the observed disruption. Explanations of the irrelevant speech effect within working memory models that specify an explicit role of attention in the maintenance of information for immediate serial recall can explain this pattern of results, whereas structural models of working memory cannot.

  17. Experimental and calculated momentum densities for the complete valence orbitals of the antimicrobial agent diacetyl

    Institute of Scientific and Technical Information of China (English)

    Su Guo-Lin; Ren Xue-Guang; Zhang Shu-Feng; Ning Chuan-Gang; Zhou Hui; Li Bin; Li Gui-Qin; Deng Jing-Kang

    2005-01-01

    The first electronic structural study of the complete valence shell binding energy spectra of the antimicrobial agent diacetyl, encompassing both the outer and inner valence regions, is reported. The binding energy spectra as well as the individual orbital momentum profiles have been measured by using a high resolution (e, 2e) electron momentum spectrometer (EMS) at an impact energy of 1200eV plus the binding energy, and using symmetric noncoplanar kinematics.The experimental orbital electron momentum profiles are compared with self-consistent field (SCF) theoretical profiles calculated using the Hartree-Fock approximation and Density Functional theory predictions in the target Kohn-Sham approximation which includes some treatment of correlation via the exchange and correlation potentials with a range of basis sets. The pole strengths of the main ionization peaks from the inner valence orbitals are estimated.

  18. Valence band structure of strained Si/(111)Si1-xGex

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The strained Si techique has been widely adopted in the high-speed and high-performance devices and circuits. Based on the valence band E-k relations of strained Si/(111)Si1-xGex, the valence band and hole effective mass along the [111] and [-110] directions were obtained in this work. In comparison with the relaxed Si, the valence band edge degeneracy was partially lifted, and the significant change was observed band structures along the [111] and [-110] directions, as well as in its corresponding hole effective masses with the increasing Ge fraction. The results obtained can provide valuable references to the investigation concerning the Si-based strained devices enhancement and the conduction channel design related to stress and orientation.

  19. Coordination Processes in International Organisations

    DEFF Research Database (Denmark)

    Nedergaard, Peter

    2008-01-01

    The EU is not a member of the International Labour Organisation (ILO), but relatively elaborate EU coordination takes place anyway. This paper addresses two research questions: 1) How is it possible to evaluate the coordination of the EU in its specific observable configuration in the ILO?, and 2......) To what outcome does this coordination lead and why? Based on an analysis of EU coordination before and during the International Labour Conference in 2005, and on a comparison with coordination processes of the IMEC group, it is found that the Commission and the Presidency act as twin-agents vis...... by the principals. On the other hand, both before and during the Conference, the Member States accept the so-called discursive coordination of the Commission, which seems to be of great (but often neglected) importance. Owing to the organisational set-up in which coordination takes place, the EU is able...

  20. A study of the valence shell photoionisation dynamics of pyrimidine and pyrazine

    Energy Technology Data Exchange (ETDEWEB)

    Holland, D.M.P., E-mail: david.holland@stfc.ac.uk [Daresbury Laboratory, Daresbury, Warrington, Cheshire WA4 4AD (United Kingdom); Potts, A.W. [Department of Physics, King' s College, Strand, London WC2R 2LS (United Kingdom); Karlsson, L. [Department of Physics, Uppsala University, Box 530, SE-751 21 Uppsala (Sweden); Stener, M.; Decleva, P. [Dipartimento di Scienze Chimiche, Universita di Trieste, Via L. Giorgieri, I-34127 Trieste (Italy); Consorzio Interuniversitario Nazionale per la Scienze e Tecnologia dei Materiali, INSTM, Unita' di Trieste, Via L. Giorgieri, I-34127 Trieste (Italy); CNR-IOM, Area Science Park - Basovizza, Strada Statale 14 km 163,5, I-34149 Trieste (Italy)

    2011-11-18

    Graphical abstract: The complete valence shell photoelectron spectra of pyrimidine and pyrazine have been recorded with synchrotron radiation and interpreted with the aid of vertical ionisation energies and relative spectral intensities calculated using time-dependent density functional theory. Highlights: Black-Right-Pointing-Pointer Valence shell photoelectron spectra of pyrimidine and pyrazine have been recorded. Black-Right-Pointing-Pointer Many-body effects are important. Black-Right-Pointing-Pointer Photoionisation dynamics are affected by shape resonances. Black-Right-Pointing-Pointer Theoretical predictions for single-hole ionic states are satisfactory. - Abstract: The complete valence shell photoelectron spectra of pyrimidine and pyrazine have been recorded with synchrotron radiation and the observed structure has been interpreted with the aid of vertical ionisation energies and relative spectral intensities calculated using time-dependent density functional theory. The theoretical predictions for the single-hole ionic states due to outer valence shell ionisation agree satisfactorily with the experimental results. Ionisation from the inner valence orbitals is strongly influenced by many-body effects and the intensity associated with a particular orbital is spread amongst numerous satellites. Photoelectron angular distributions and partial cross sections have been determined both experimentally and theoretically, and demonstrate that shape resonances affect the valence shell photoionisation dynamics. In addition to shape resonances occurring a few eV above the ionisation threshold, the calculations indicate that many of the orbitals are influenced by shape resonant processes at much higher energies. Some of these higher energy resonances have been confirmed through a comparison between the relevant theoretical and experimental photoelectron asymmetry parameters. The spectral behaviour of asymmetry parameters associated with {pi}-orbitals has been shown to

  1. A STUDY OF TEMPERATURE-DEPENDENT VALENCE BOND STRUCTURE OF TITANIUM

    Institute of Scientific and Technical Information of China (English)

    X.B. Li; Y.Q. Xie; Y.Z. Nie; H.J. Peng; H.J. Tao; F.X. Yu

    2007-01-01

    On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is ec2.9907 .(sc0.4980 + dc2.4927) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.

  2. Valence photoelectron spectra of alkali bromides calculated within the propagator theory

    DEFF Research Database (Denmark)

    Karpenko, Alexander; Iablonskyi, Denys; Aksela, Helena

    2013-01-01

    The valence ionization spectra covering the binding energy range 0-45 eV of alkali bromide XBr (X = Li, Na, K, Rb) vapors are studied within the framework of the propagator theory. Relativistic Algebraic Diagrammatic Construction calculations have been carried out in order to investigate photoion......The valence ionization spectra covering the binding energy range 0-45 eV of alkali bromide XBr (X = Li, Na, K, Rb) vapors are studied within the framework of the propagator theory. Relativistic Algebraic Diagrammatic Construction calculations have been carried out in order to investigate...

  3. Inducing changes in arousal and valence: comparison of two mood induction procedures.

    Science.gov (United States)

    Jallais, Christophe; Gilet, Anne-Laure

    2010-02-01

    This research examined the relative effectiveness of two mood induction procedures (MIPs) for inducing four specific moods varying along the dimensions of both valence and arousal. Participants were randomly assigned either to an autobiographical recall or to a music and guided imagery MIP and underwent a happiness, serenity, anger, or sadness mood induction. The findings confirmed the effectiveness of the two MIPs in producing changes on both the valence and arousal dimensions of mood. The results also revealed an unexpected greater efficiency of the autobiographical recall than of the combined procedure.

  4. Generalized oscillator strengths for some higher valence-shell excitations of krypton atom

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The valence-shell excitations of krypton atom have been investigated by fast electron impact with an angle-resolved electron-energy-loss spectrometer. The generalized oscillator strengths for some higher mixed valence-shell excitations in 4d, 4f, 5p, 5d, 6s, 6p, 7s ← 4p of krypton atom have been determined. Their profiles are discussed, and the generalized oscillator strengths for the electric monopole and quadrupole excitations in 5p ← 4p are compared with the calculations of Amusia et al. (Phys. Rev. A 67 022703 (2003)). The differences between the experimental results and theoretical calculations show that more studies are needed.

  5. High-Resolution Conversion Electron Spectroscopy of Valence Electron Configurations (CESVEC) in Solids

    CERN Multimedia

    2002-01-01

    First measurements with the Zurich $\\beta$-spectrometer on sources from ISOLDE have demonstrated that high resolution spectroscopy of conversion electrons from valence shells is feasible.\\\\ \\\\ This makes possible a novel type of electron spectroscopy (CESVEC) on valence-electron configurations of tracer elements in solids. Thus the density of occupied electron states of impurities in solids has been measured for the first time. Such data constitute a stringent test of state-of-the-art calculations of impurity properties. Based on these results, we are conducting a systematic investigation of impurities in group IV and III-V semiconductors.

  6. Coordination using Implicit Communication

    CERN Document Server

    Cuff, Paul

    2011-01-01

    We explore a basic noise-free signaling scenario where coordination and communication are naturally merged. A random signal X_1,...,X_n is processed to produce a control signal or action sequence A_1,...,A_n, which is observed and further processed (without access to X_1,...,X_n) to produce a third sequence B_1,...,B_n. The object of interest is the set of empirical joint distributions p(x,a,b) that can be achieved in this setting. We show that H(A) >= I(X;A,B) is the necessary and sufficient condition for achieving p(x,a,b) when no causality constraints are enforced on the encoders. We also give results for various causality constraints. This setting sheds light on the embedding of digital information in analog signals, a concept that is exploited in digital watermarking, steganography, cooperative communication, and strategic play in team games such as bridge.

  7. On Coordinating Collaborative Objects

    CERN Document Server

    Imine, Abdessamad

    2010-01-01

    A collaborative object represents a data type (such as a text document) designed to be shared by a group of dispersed users. The Operational Transformation (OT) is a coordination approach used for supporting optimistic replication for these objects. It allows the users to concurrently update the shared data and exchange their updates in any order since the convergence of all replicas, i.e. the fact that all users view the same data, is ensured in all cases. However, designing algorithms for achieving convergence with the OT approach is a critical and challenging issue. In this paper, we propose a formal compositional method for specifying complex collaborative objects. The most important feature of our method is that designing an OT algorithm for the composed collaborative object can be done by reusing the OT algorithms of component collaborative objects. By using our method, we can start from correct small collaborative objects which are relatively easy to handle and incrementally combine them to build more ...

  8. Coordinating Group report

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    In December 1992, western governors and four federal agencies established a Federal Advisory Committee to Develop On-site Innovative Technologies for Environmental Restoration and Waste Management (the DOIT Committee). The purpose of the Committee is to advise the federal government on ways to improve waste cleanup technology development and the cleanup of federal sites in the West. The Committee directed in January 1993 that information be collected from a wide range of potential stakeholders and that innovative technology candidate projects be identified, organized, set in motion, and evaluated to test new partnerships, regulatory approaches, and technologies which will lead to improve site cleanup. Five working groups were organized, one to develop broad project selection and evaluation criteria and four to focus on specific contaminant problems. A Coordinating Group comprised of working group spokesmen and federal and state representatives, was set up to plan and organize the routine functioning of these working groups. The working groups were charged with defining particular contaminant problems; identifying shortcomings in technology development, stakeholder involvement, regulatory review, and commercialization which impede the resolution of these problems; and identifying candidate sites or technologies which could serve as regional innovative demonstration projects to test new approaches to overcome the shortcomings. This report from the Coordinating Group to the DOIT Committee highlights the key findings and opportunities uncovered by these fact-finding working groups. It provides a basis from which recommendations from the DOIT Committee to the federal government can be made. It also includes observations from two public roundtables, one on commercialization and another on regulatory and institutional barriers impeding technology development and cleanup.

  9. Stronger Association Between Valence- and Arousal Ratings of Affective Pictures with Older Age: Evidence for Variation Across Emotion Categories

    DEFF Research Database (Denmark)

    Mikkelsen, Mai Bjørnskov; Mehlsen, Mimi Yung; Lyby, Marlene Skovgaard;

    A sample of older and younger adults rated affective pictures according to valence, arousal and emotion category (happiness, sadness and disgust). Results indicate that older age is associated with a stronger linear association between ratings of arousal and valence. Further, the strength...... of the association vary according to emotion category....

  10. Intergroup Discrimination in Positive and Negative Outcome Allocations: Impact of Stimulus Valence, Relative Group Status, and Relative Group Size.

    Science.gov (United States)

    Otten, Sabine; And Others

    1996-01-01

    Three studies investigated the determination of social discrimination by the valence of stimuli that are allocated between groups. The studies were based on either the minimal group paradigm or a more reality-based laboratory intergroup setting, with stimulus valence, group status, and group size as factors and with pull scores on Tajfel matrices…

  11. Intergroup discrimination in positive and negative outcome allocations : Impact of stimulus valence, relative group status, and relative group size

    NARCIS (Netherlands)

    Otten, S; Mummendey, A; Blanz, M

    1996-01-01

    Three studies investigated the determination of social discrimination by the valence of stimuli that are allocated between groups. The studies were based on either the minimal group paradigm or a more reality-based laboratory intergroup setting, with stimulus valence, group status, and group size as

  12. Hydrogen release reactions of Al-based complex hydrides enhanced by vibrational dynamics and valences of metal cations.

    Science.gov (United States)

    Sato, T; Ramirez-Cuesta, A J; Daemen, L; Cheng, Y-Q; Tomiyasu, K; Takagi, S; Orimo, S

    2016-09-27

    Hydrogen release from Al-based complex hydrides composed of metal cation(s) and [AlH4](-) was investigated using inelastic neutron scattering viewed from vibrational dynamics. The hydrogen release followed the softening of translational and [AlH4](-) librational modes, which was enhanced by vibrational dynamics and the valence(s) of the metal cation(s).

  13. The Synthesis of NiO/TiO2 Heterostructures and Their Valence Band Offset Determination

    Directory of Open Access Journals (Sweden)

    Z. H. Ibupoto

    2014-01-01

    Full Text Available In this work, a heterojunction based on p-type NiO/n-type TiO2 nanostructures has been prepared on the fluorine doped tin oxide (FTO glass substrate by hydrothermal method. Scanning electron microscopy (SEM and X-Ray diffraction techniques were used for the morphological and crystalline arrays characterization. The X-ray photoelectron spectroscopy was employed to determine the valence-band offset (VBO of the NiO/TiO2 heterojunction prepared on FTO glass substrate. The core levels of Ni 2p and Ti 2p were utilized to align the valence-band offset of p-type NiO/n-type TiO2 heterojunction. The valence band offset was found to be ∼0.41 eV and the conduction band was calculated about ∼0.91 eV. The ratio of conduction band offset and the valence-band offset was found to be 2.21.

  14. Voice and Valence-Altering Operations in Falam Chin: A Role and Reference Grammar Approach

    Science.gov (United States)

    King, Deborah

    2010-01-01

    This dissertation describes and analyzes voice and valence-altering operations in Falam Chin, a Tibeto-Burman language of Burma. The data is explained within the framework of Role and Reference Grammar (RRG), which supplies several key concepts particularly useful for generalizing the behavior of the Falam Chin operations. The first is RRG's…

  15. Brain activations to emotional pictures are differentially associated with valence and arousal ratings

    Directory of Open Access Journals (Sweden)

    Antje B M Gerdes

    2010-10-01

    Full Text Available Several studies have investigated the neural responses triggered by emotional pictures, but the specificity of the involved structures such as the amygdala or the ventral striatum is still under debate. Furthermore, only few studies examined the association of stimuli’s valence and arousal and the underlying brain responses. Therefore, we investigated brain responses with functional magnetic resonance imaging of 17 healthy subjects to pleasant and unpleasant affective pictures with comparable arousal levels and afterwards assessed ratings of valence and arousal. As expected, unpleasant pictures strongly activated the right and left amygdala, the right hippocampus, and the medial occipital lobe, whereas pleasant pictures elicited significant activations in left occipital regions, and in parts of the medial temporal lobe. The direct comparison of unpleasant and pleasant pictures which were comparable in arousal clearly indicated stronger amygdala activation in response to the unpleasant pictures. Most important, correlational analyses revealed on the one hand that the arousal of unpleasant pictures was significantly associated with activations in the right amygdala and the left caudate body. On the other hand, valence of pleasant pictures was significantly correlated with activations in the right caudate head, extending to the nucleus accumbens (NAcc and the left dorso-lateral prefrontal cortex. These findings support the notion that the amygdala is primarily involved in processing of unpleasant stimuli, and the stronger the more arousing the stimuli are, whereas reward-related structures like the NAcc primarily responds to pleasant stimuli, the stronger the more positive the valence of these stimuli is.

  16. Valence photoelectron spectra of alkali bromides calculated within the propagator theory.

    Science.gov (United States)

    Karpenko, Alexander; Iablonskyi, Denys; Aksela, Helena

    2013-04-28

    The valence ionization spectra covering the binding energy range 0-45 eV of alkali bromide XBr (X = Li, Na, K, Rb) vapors are studied within the framework of the propagator theory. Relativistic Algebraic Diagrammatic Construction calculations have been carried out in order to investigate photoionization processes and to describe molecular electronic structure. Theoretical results are compared with available experimental data.

  17. The effect of an extinction cue on ABA-renewal: Does valence matter?

    NARCIS (Netherlands)

    Dibbets, P.; Maes, J.H.R.

    2011-01-01

    The present human fear conditioning study examined whether the valence of an extinction cue has a differential effect on attenuating renewal that is induced by removal of the extinction context. Additionally, the study aimed to assess whether such attenuating effect is based on a modulatory or safet

  18. The Effect of an Extinction Cue on ABA-Renewal: Does Valence Matter?

    Science.gov (United States)

    Dibbets, Pauline; Maes, Joseph H. R.

    2011-01-01

    The present human fear conditioning study examined whether the valence of an extinction cue has a differential effect on attenuating renewal that is induced by removal of the extinction context. Additionally, the study aimed to assess whether such attenuating effect is based on a modulatory or safety-signal role of the cue. In acquisition,…

  19. Automatic evaluation isn't that crude! Moderation of masked affective priming by type of valence

    NARCIS (Netherlands)

    Wentura, D.; Degner, J.

    2010-01-01

    In two experiments, the automatic processing of evaluative information was investigated using a masked affective priming paradigm, varying valence (positive vs. negative) and relevance (other-relevant traits vs. possessor-relevant traits; Peeters, 1983) of prime and target stimuli. It was found that

  20. Synthesis, Characterization, and Antibacterial Activities of High-Valence Silver Propamidine Nanoparticles

    Directory of Open Access Journals (Sweden)

    Jinran Lee

    2017-07-01

    Full Text Available Diabetic foot ulcer (DFU is becoming more serious concern as it affects 95% of diabetic patients worldwide. It has been shown that the Staphylococcus aureus and other Gram-negative microorganisms are the main reasons behind this disease. Though many antibiotics are presently used to treat the DFU, due to increased bacterial resistance, new alternative therapies are always welcome. To address this alarming issue, we have designed and synthesized the high-valence silver propamidine (Ag(IIPRO complex as well as nanoparticles and characterized both by usual spectroscopic methods. The reverse microemulsion technique has been applied to synthesize Ag(IIPRO nanoparticles and its antibacterial activity has been compared with zero-valence silver nanoparticles (AgNPs with similar size. The antibacterial efficacies of Ag(IIPRO nanoparticles and AgNPs were tested against Gram-negative and Gram -positive organisms responsible for DFU. The newly synthesized high-valence Ag(IIPRO nanoparticles showed higher antibacterial activity compared to silver-only nanoparticles (AgNPs. This study concludes that the high-valence Ag(IIPRO nanoparticles show better antibacterial activity than AgNPs and they may serve as the next generation therapeutic agent for the diabetic wound care.

  1. Memory effects of sleep, emotional valence, arousal and novelty in children

    NARCIS (Netherlands)

    Vermeulen, Marije C M; van der Heijden, Kristiaan B; Benjamins, Jeroen S; Swaab, Hanna; van Someren, Eus J W

    2017-01-01

    Effectiveness of memory consolidation is determined by multiple factors, including sleep after learning, emotional valence, arousal and novelty. Few studies investigated how the effect of sleep compares with (and interacts with) these other factors, of which virtually none are in children. The

  2. An ab initio Valence Bond Study on Cyclopenta-Fused Naphthalenes and Fluoranthenes

    NARCIS (Netherlands)

    Havenith, R.W.A.; van Lenthe, J.H.; Jenneskens, L.W.

    2005-01-01

    To probe the effect of external cyclopenta-fusion on a naphthalene core, ab initio valence bond (VB) calculations have been performed, using strictly atomic benzene p-orbitals and p-orbitals that are allowed to delocalize, on naphthalene (1), acenaphthylene (2), pyracylene (3), cyclopenta[b,c]-acena

  3. Memory effects of sleep, emotional valence, arousal and novelty in children

    NARCIS (Netherlands)

    Vermeulen, Marije C M; van der Heijden, Kristiaan B; Benjamins, Jeroen S; Swaab, Hanna; van Someren, Eus J W

    2017-01-01

    Effectiveness of memory consolidation is determined by multiple factors, including sleep after learning, emotional valence, arousal and novelty. Few studies investigated how the effect of sleep compares with (and interacts with) these other factors, of which virtually none are in children. The prese

  4. Reproducing affective norms with lexical co-occurrence statistics : Predicting valence, arousal, and dominance

    NARCIS (Netherlands)

    Louwerse, M.M.; Recchia, G.

    2014-01-01

    Human ratings of valence, arousal, and dominance are frequently used to study the cognitive mechanisms of emotional attention, word recognition, and numerous other phenomena in which emotions are hypothesized to play an important role. Collecting such norms from human raters is expensive and time

  5. Memory transfer for emotionally valenced words between identities in dissociative identity disorder

    NARCIS (Netherlands)

    Huntjens, Rafaele J. C.; Peters, Madelon L.; Woertman, Liesbeth; van der Hart, Onno; Postma, Albert

    The present study aimed to determine interidentity retrieval of emotionally valenced words in dissociative identity disorder (DID). Twenty-two DID patients participated together with 25 normal controls and 25 controls instructed to simulate DID. Two wordlists A and B were constructed including

  6. Cheminoes: A Didactic Game to Learn Chemical Relationships between Valence, Atomic Number, and Symbol

    Science.gov (United States)

    Moreno, Luis F.; Hincapié, Gina; Alzate, María Victoria

    2014-01-01

    Cheminoes is a didactic game that enables the meaningful learning of some relations between concepts such as chemical element, valence, atomic number, and chemical symbol for the first 36 chemical elements of the periodic system. Among the students who have played the game, their opinions of the activity were positive, considering the game to be a…

  7. Neural modulation of directed forgetting by valence and arousal: An event-related potential study.

    Science.gov (United States)

    Gallant, Sara N; Dyson, Benjamin J

    2016-10-01

    Intentional forgetting benefits memory by removing no longer needed information and promoting processing of more relevant materials. This study sought to understand how the behavioural and neurophysiological representation of intentional forgetting would be impacted by emotion. We took a novel approach by examining the unique contribution of both valence and arousal on emotional directed forgetting. Participants completed an item directed forgetting task for positive, negative, and neutral words at high and lower levels of arousal while brain activity was recorded using electroencephalography (EEG). Behaviourally, recognition of to-be-remembered (TBR) and to-be-forgotten (TBF) items varied as a function of valence and arousal with reduced directed forgetting for high arousing negative and neutral words. In the brain, patterns of frontal and posterior activation in response to TBF and TBR cues respectively replicated prior EEG evidence to support involvement of inhibitory and selective rehearsal mechanisms in item directed forgetting. Interestingly, emotion only impacted cue-related posterior activity, which varied depending on specific interactions between valence and arousal. Together, results suggest that the brain handles valence and arousal differently and highlights the importance of considering in a collective manner the multidimensional nature of emotion in experimentation.

  8. Cheminoes: A Didactic Game to Learn Chemical Relationships between Valence, Atomic Number, and Symbol

    Science.gov (United States)

    Moreno, Luis F.; Hincapié, Gina; Alzate, María Victoria

    2014-01-01

    Cheminoes is a didactic game that enables the meaningful learning of some relations between concepts such as chemical element, valence, atomic number, and chemical symbol for the first 36 chemical elements of the periodic system. Among the students who have played the game, their opinions of the activity were positive, considering the game to be a…

  9. Calculation of the valence electron structures of alloying cementite and its biphase interface

    Institute of Scientific and Technical Information of China (English)

    刘志林; 李志林; 刘伟东

    2001-01-01

    The valence electron structures of alloying cementite θ-(Fe, M)3C and ε-(Fe, M)3C andthose of the biphase interfaces between them and α-Fe are calculated with Yu's empirical electrontheory of solid and molecules. The calculation results accord with the actual behavior of alloys.

  10. XPEEM valence state imaging of mineral micro-intergrowths with a spatial resolution of 100nm

    Science.gov (United States)

    Smith, A. D.; Schofield, P. F.; Scholl, A.; Pattrick, R. A. D.; Bridges, J. C.

    2003-03-01

    The crystal chemistry and textural relationships of minerals hold a vast amount of information relating to the formation, history and stability of natural materials. The application of soft X-ray spectroscopy to mineralogical material has revealed that 2p (L{2,3}) spectra provide a sensitive fingerprint of the electronic states of 3d metals. In bulk powdered samples much of the textural and microstructural information is lost, but the area-selectivity capability of X-ray Photo-Emission Electron Microscopy (XPEEM) provides the ability to obtain valence state information from mineral intergrowths with a submicron spatial resolution. Using the state-of-the-art PEEM2 facility on beamline 7.3.1.1 at the Advanced Light Source, Berkeley, USA, a range of minerals, mineral intergrowths and mineralogical textures have been studied for a broad suite of geological, planetary and environmental science materials. High-quality, multi-element valence images have been obtained showing the distribution/variation of the metal valence states across single grains or mineral intergrowths/textures at the l00 nm scale and quantitative valence state ratios can be obtained from areas of 0.01 μ m^2.

  11. Mixed Meson Mass for Domain-Wall Valence and Staggered Sea Fermions

    Energy Technology Data Exchange (ETDEWEB)

    Konstantinos Orginos; Andre Walker-Loud

    2007-05-01

    Mixed action lattice calculations allow for an additive lattice spacing dependent mass renormalization of mesons composed of one sea and one valence quark, regardless of the type of fermion discretization methods used in the valence and sea sectors. The value of the mass renormalization depends upon the lattice actions used. This mixed meson mass shift is the most important lattice artifact to determine for mixed action calculations: because it modifies the pion mass, it plays a central role in the low energy dynamics of all hadronic correlation functions. We determine the leading order and next to leading order additive mass renormalization of valence-sea mesons for a mixed lattice action with domain-wall valence fermions and staggered sea fermions. We find that on the asqtad improved coarse MILC lattices, the leading order additive mass renormalization for the mixed mesons is Δ(am)^2 LO = 0.0409(11) which corresponds to a^2 Δ_Mix = (319 MeV)^2± (53 MeV)^2 for a = 0.125 fm. We also find significant next to leading order contributions which reduce the mass renormalization by a significant amount, such that for 0 < am_π ≤ 0.22 the mixed meson mass renormalization is well approximated by Δ(am)^2 = 0.0340 (23) or a^2δ_Mix = (290 MeV)^2 ± (76 MeV)^2. The full next-to-leading order analysis is presented in the text.

  12. Valence-based age differences in medial prefrontal activity during impression formation.

    Science.gov (United States)

    Cassidy, Brittany S; Leshikar, Eric D; Shih, Joanne Y; Aizenman, Avigael; Gutchess, Angela H

    2013-01-01

    Reports of age-related changes to medial prefrontal cortex (mPFC) activity during socio-cognitive tasks have shown both age-equivalence and under recruitment. Emotion work illustrates selective mPFC response dependent on valence, such that negative emotional images evoke increased ventral mPFC activity for younger adults, while older adults recruit vmPFC more for positive material. By testing whether this differential age-related response toward valenced material is also present for the social task of forming impressions, we may begin to understand inconsistencies regarding when age differences are present vs. absent in the literature. Using fMRI, participants intentionally formed impressions of positive and negative face-behavior pairs in anticipation of a memory task. Extending previous findings to a social task, valence-based reversals were present in dorsal and ventral mPFC, and posterior cingulate cortex. Younger adults elicited increased activity when forming negative impressions, while older adults had more recruitment when forming positive impressions. This suggests an age-related shift toward emphasizing positive social information may be reflected in the recruitment of regions supporting forming impressions. Overall, the results indicate an age-related shift in neural response to socio-cognitive stimuli that is valence dependent rather than a general age-related reduction in activity, in part informing prior inconsistencies within the literature.

  13. The stabilities and electron structures of Al-Mg clusters with 18 and 20 valence electrons

    Science.gov (United States)

    Yang, Huihui; Chen, Hongshan

    2017-07-01

    The spherical jellium model predicts that metal clusters having 18 and 20 valence electrons correspond to the magic numbers and will show specific stabilities. We explore in detail the geometric structures, stabilities and electronic structures of Al-Mg clusters containing 18 and 20 valence electrons by using genetic algorithm combined with density functional theories. The stabilities of the clusters are governed by the electronic configurations and Mg/Al ratios. The clusters with lower Mg/Al ratios are more stable. The molecular orbitals accord with the shell structures predicted by the jellium model but the 2S level interweaves with the 1D levels and the 2S and 1D orbitals form a subgroup. The clusters having 20 valence electrons form closed 1S21P61D102S2 shells and show enhanced stability. The Al-Mg clusters with a valence electron count of 18 do not form closed shells because one 1D orbital is unoccupied. The ionization potential and electron affinity are closely related to the electronic configurations; their values are determined by the subgroups the HOMO or LUMO belong to. Supplementary material in the form of one pdf file available from the Journal web page at http://https://doi.org/10.1140/epjd/e2017-80042-9

  14. Valence band hybridization in N-rich GaN1-xAsx alloys

    Energy Technology Data Exchange (ETDEWEB)

    Wu, J.; Walukiewicz, W.; Yu, K.M.; Denlinger, J.D.; Shan, W.; Ager III, J.W.; Kimura, A.; Tang, H.F.; Kuech, T.F.

    2004-05-04

    We have used photo-modulated transmission and optical absorption spectroscopies to measure the composition dependence of interband optical transitions in N-rich GaN{sub 1-x}As{sub x} alloys with x up to 0.06. The direct bandgap gradually decreases as x increases. In the dilute x limit, the observed band gap approaches 2.8 eV; this limiting value is attributed to a transition between the As localized level, which has been previously observed in As-doped GaN at 0.6 eV above the valence band maximum in As-doped GaN, and the conduction band minimum. The structure of the valence band of GaN{sub 1-x}As{sub x} is explained by the hybridization of the localized As states with the extended valence band states of GaN matrix. The hybridization is directly confirmed by soft x-ray emission experiments. To describe the electronic structure of the GaN{sub 1-x}As{sub x} alloys in the entire composition range a linear interpolation is used to combine the effects of valence band hybridization in N-rich alloys with conduction band anticrossing in As-rich alloys.

  15. Core and Valence Structures in K beta X-ray Emission Spectra of Chromium Materials

    NARCIS (Netherlands)

    Torres Deluigi, Maria; de Groot, Frank M. F.|info:eu-repo/dai/nl/08747610X; Lopez-Diaz, Gaston; Tirao, German; Stutz, Guillermo; Riveros de la Vega, Jose

    2014-01-01

    We analyze the core and valence transitions in chromium in a series of materials with a number of different ligands and including the oxidation states: Cr-II, Cr-III, Cr-IV, and Cr-VI. To study the core-to-core transitions we employ the CTM4XAS program and investigate the shapes, widths,

  16. Size-extensive wave functions for quantum Monte Carlo: A linear scaling generalized valence bond approach

    NARCIS (Netherlands)

    Fracchia, F.; Filippi, C.; Amovilli, C.

    2012-01-01

    We propose a new class of multideterminantal Jastrow–Slater wave functions constructed with localized orbitals and designed to describe complex potential energy surfaces of molecular systems for use in quantum Monte Carlo (QMC). Inspired by the generalized valence bond formalism, we elaborate a coup

  17. Alteration of Expected Hemispheric Asymmetries: Valence and Arousal Effects in Neuropsychological Models of Emotion

    Science.gov (United States)

    Alfano, Keith M.; Cimino, Cynthia R.

    2008-01-01

    The relative advantage of the left (LH) over the right hemisphere (RH) in processing of verbal material for most individuals is well established. Nevertheless, several studies have reported the ability of positively and negatively valenced stimuli to enhance and reverse, respectively, the usual LH greater than RH asymmetry. These studies, however,…

  18. Talking about alcohol consumption: health campaigns, conversational valence, and binge drinking intentions

    NARCIS (Netherlands)

    Hendriks, H.; de Bruijn, G.-J.; van den Putte, B.

    2012-01-01

    Objectives. Although research has shown that whether people talk about health issues influences health campaign effects, no evidence exists on whether conversational valence fulfils a mediating role within health campaign effects. In the context of alcohol consumption, this two-wave experimental res

  19. Determining binding energies of valence-band electrons in insulators and semiconductors via lanthanide spectroscopy

    NARCIS (Netherlands)

    Dorenbos, P.

    2013-01-01

    Models and methods to determine the absolute binding energy of 4f-shell electrons in lanthanide dopants will be combined with data on the energy of electron transfer from the valence band to a lanthanide dopant. This work will show that it provides a powerful tool to determine the absolute binding e

  20. Memory transfer for emotionally valenced words between identities in dissociative identity disorder

    NARCIS (Netherlands)

    Huntjens, Rafaele J. C.; Peters, Madelon L.; Woertman, Liesbeth; van der Hart, Onno; Postma, Albert

    2007-01-01

    The present study aimed to determine interidentity retrieval of emotionally valenced words in dissociative identity disorder (DID). Twenty-two DID patients participated together with 25 normal controls and 25 controls instructed to simulate DID. Two wordlists A and B were constructed including neutr

  1. Age-related emotional bias in processing two emotionally valenced tasks.

    Science.gov (United States)

    Allen, Philip A; Lien, Mei-Ching; Jardin, Elliott

    2017-01-01

    Previous studies suggest that older adults process positive emotions more efficiently than negative emotions, whereas younger adults show the reverse effect. We examined whether this age-related difference in emotional bias still occurs when attention is engaged in two emotional tasks. We used a psychological refractory period paradigm and varied the emotional valence of Task 1 and Task 2. In both experiments, Task 1 was emotional face discrimination (happy vs. angry faces) and Task 2 was sound discrimination (laugh, punch, vs. cork pop in Experiment 1 and laugh vs. scream in Experiment 2). The backward emotional correspondence effect for positively and negatively valenced Task 2 on Task 1 was measured. In both experiments, younger adults showed a backward correspondence effect from a negatively valenced Task 2, suggesting parallel processing of negatively valenced stimuli. Older adults showed similar negativity bias in Experiment 2 with a more salient negative sound ("scream" relative to "punch"). These results are consistent with an arousal-bias competition model [Mather and Sutherland (Perspectives in Psychological Sciences 6:114-133, 2011)], suggesting that emotional arousal modulates top-down attentional control settings (emotional regulation) with age.

  2. The interaction of arousal and valence in affective priming: behavioral and electrophysiological evidence.

    Science.gov (United States)

    Zhang, Qin; Kong, Lingyue; Jiang, Yang

    2012-09-20

    The affective priming paradigm has been studied extensively and applied in many fields during the past two decades. Most research thus far has focused on the valence dimension. Whether emotional arousal influences affective priming remains poorly understood. The present study demonstrates how arousal impacts evaluation of affective words using reaction time and event-related potential (ERP) measures. Eighteen younger subjects evaluated pleasantness of target words after seeing affective pictures as primes. The participants' responses were faster and/or more accurate for valence-congruent trials than for incongruent trials, particularly with high-arousal stimuli. An ERP affective priming effect (N400) also occurred mainly in high-arousing stimulus pairs. In addition, whereas valence congruency influenced both the N400 and the LPP, arousal congruency influenced only the LPP, suggesting that arousal congruency mainly modulates post-semantic processes, but valence congruency effects begin with semantic processes. Overall, our current findings indicate that the arousal level of visual images impacts both behavioral and ERP effects of affective priming.

  3. Invariant manifolds and collective coordinates

    Energy Technology Data Exchange (ETDEWEB)

    Papenbrock, T. [Centro Internacional de Ciencias, Cuernavaca, Morelos (Mexico); Institute for Nuclear Theory, University of Washington, Seattle, WA (United States); Seligman, T.H. [Centro Internacional de Ciencias, Cuernavaca, Morelos (Mexico); Centro de Ciencias Fisicas, University of Mexico (UNAM), Cuernavaca (Mexico)

    2001-09-14

    We introduce suitable coordinate systems for interacting many-body systems with invariant manifolds. These are Cartesian in coordinate and momentum space and chosen such that several components are identically zero for motion on the invariant manifold. In this sense these coordinates are collective. We make a connection to Zickendraht's collective coordinates and present certain configurations of few-body systems where rotations and vibrations decouple from single-particle motion. These configurations do not depend on details of the interaction. (author)

  4. Derivation and Testing of Explicit Equations of Motion for Polymers Described by Internal Coordinates

    Science.gov (United States)

    Mazur, A. K.; Dorofeev, V. E.; Abagyan, R. A.

    1991-02-01

    General Lagrange's equations of motion for a system of polymeric molecules are obtained in an explicit form. They can be used for simulating molecular dynamics of large molecules. The molecular conformations are described by internal coordinates, i.e., bond lengths, valence angles, and torsion angles. The equations derived permit any internal degrees of freedom to be frozen. The method is applied to an oligopeptide in an α-helical conformation. Three models of the molecule with different degrees of fixation are compared. It is shown that the method permits one to increase significantly the time step in molecular dynamics calculations.

  5. A series of Ti(IV)/Ti(III) coordination polymers: structures and surface photoelectric properties.

    Science.gov (United States)

    Li, Lei; Zhang, Li; Liu, Dong-Wei; Jin, Jing; Chi, Yu-Xian; Niu, Shu-Yun

    2012-02-01

    Three titanium coordination polymers, {[Ti(SO(4))(2)(H(2)O)]·0.5bipy·2H(2)O}(n)1, {[Ti1(SO(4))(2)(H(2)O)]·[Ti2(SO(4))(2)(H(2)O)]·bipy·5H(2)O}(n)2 and [Ti(tea)](n)3 (bipy=4,4'-bipyridine, H(3)tea=triethanolamine) were synthesized and characterized by IR, UV-Vis absorption spectra, TG analysis, X-ray single crystal diffraction and surface photovoltage spectroscopy (SPS). The surface photoelectric properties of titanium coordination polymers were discussed emphatically by the SPS. The results of single crystal diffraction indicate that polymers 1 and 2 possess 1D infinite structure bridged by SO(4)(2-) groups and coordinated water molecules and further connected into supramolecular structures by hydrogen bonds. Polymer 3 possesses 2D infinite structure bridged by weak sub-coordinated Ti-O bonds. The results of SPS show that there are obvious photovoltage responses in the range of 300-500 nm, which indicates that they possess photoelectric conversion ability. The SPS of three titanium polymers were analyzed comparatively. It is found that the valence of central metal ions, coordination micro-environment and kinds of coordination atoms influence the results of the SPS. The SPS is associated with UV-Vis absorption spectra.

  6. A series of Ti(IV)/Ti(III) coordination polymers: Structures and surface photoelectric properties

    Science.gov (United States)

    Li, Lei; Zhang, Li; Liu, Dong-Wei; Jin, Jing; Chi, Yu-Xian; Niu, Shu-Yun

    2012-02-01

    Three titanium coordination polymers, {[Ti(SO 4) 2(H 2O)]·0.5bipy·2H 2O} n1, {[Ti1(SO 4) 2(H 2O)]·[Ti2(SO 4) 2(H 2O)]·bipy·5H 2O} n2 and [Ti(tea)] n3 (bipy = 4,4'-bipyridine, H 3tea = triethanolamine) were synthesized and characterized by IR, UV-Vis absorption spectra, TG analysis, X-ray single crystal diffraction and surface photovoltage spectroscopy (SPS). The surface photoelectric properties of titanium coordination polymers were discussed emphatically by the SPS. The results of single crystal diffraction indicate that polymers 1 and 2 possess 1D infinite structure bridged by SO 42- groups and coordinated water molecules and further connected into supramolecular structures by hydrogen bonds. Polymer 3 possesses 2D infinite structure bridged by weak sub-coordinated Ti-O bonds. The results of SPS show that there are obvious photovoltage responses in the range of 300-500 nm, which indicates that they possess photoelectric conversion ability. The SPS of three titanium polymers were analyzed comparatively. It is found that the valence of central metal ions, coordination micro-environment and kinds of coordination atoms influence the results of the SPS. The SPS is associated with UV-Vis absorption spectra.

  7. Facial and semantic emotional interference: A pilot study on the behavioral and cortical responses to the dual valence association task

    Directory of Open Access Journals (Sweden)

    Petroni Agustín

    2011-04-01

    Full Text Available Abstract Background Integration of compatible or incompatible emotional valence and semantic information is an essential aspect of complex social interactions. A modified version of the Implicit Association Test (IAT called Dual Valence Association Task (DVAT was designed in order to measure conflict resolution processing from compatibility/incompatibly of semantic and facial valence. The DVAT involves two emotional valence evaluative tasks which elicits two forms of emotional compatible/incompatible associations (facial and semantic. Methods Behavioural measures and Event Related Potentials were recorded while participants performed the DVAT. Results Behavioural data showed a robust effect that distinguished compatible/incompatible tasks. The effects of valence and contextual association (between facial and semantic stimuli showed early discrimination in N170 of faces. The LPP component was modulated by the compatibility of the DVAT. Conclusions Results suggest that DVAT is a robust paradigm for studying the emotional interference effect in the processing of simultaneous information from semantic and facial stimuli.

  8. High Valence, Normal Valence and Unknown Valence

    DEFF Research Database (Denmark)

    Morsing, Thorbjørn Juul

    )3]+ with X = Cl and Br. The extreme kinetic robustness of the Ir(III) centers prevents chloride abstraction by Ag(I) and the unusual complexes are formed instead. A ligand eld and ab initio study of the ligand complexes [IrX3(NCCH3)3] is performed and compared to the silver complexes and it is found...... of for instance incorporating the carbide functionality into other systems. Several chapters and papers include X-ray spectroscopy measurements and a very brief introduction to the techniques is given in Appendix A. Throughout the thesis computational studies of various kinds have been used to help...... the elucidation of experimental observations and a brief study on the computation of ligand eld transitions in transition metal complexes is given in Appendix B....

  9. Coordination Control Of Complex Machines

    NARCIS (Netherlands)

    J.C.M. Baeten; B. van Beek; J. Markovski; L.J.A.M. Somers

    2015-01-01

    Control and coordination are important aspects of the development of complex machines due to an ever-increasing demand for better functionality, quality, and performance. In WP6 of the C4C project, we developed a synthesis-centric systems engineering framework suitable for supervisory coordination o

  10. Coordinate-Free Rotation Operator.

    Science.gov (United States)

    Leubner, C.

    1979-01-01

    Suggests the use of a coordinate-free rotation operator for the teaching of rotations in Euclidean three space because of its twofold didactic advantage. Illustrates the potentialities of the coordinate-free rotation operator approach by a number of examples. (Author/GA)

  11. Coordination of Conditional Poisson Samples

    Directory of Open Access Journals (Sweden)

    Grafström Anton

    2015-12-01

    Full Text Available Sample coordination seeks to maximize or to minimize the overlap of two or more samples. The former is known as positive coordination, and the latter as negative coordination. Positive coordination is mainly used for estimation purposes and to reduce data collection costs. Negative coordination is mainly performed to diminish the response burden of the sampled units. Poisson sampling design with permanent random numbers provides an optimum coordination degree of two or more samples. The size of a Poisson sample is, however, random. Conditional Poisson (CP sampling is a modification of the classical Poisson sampling that produces a fixed-size πps sample. We introduce two methods to coordinate Conditional Poisson samples over time or simultaneously. The first one uses permanent random numbers and the list-sequential implementation of CP sampling. The second method uses a CP sample in the first selection and provides an approximate one in the second selection because the prescribed inclusion probabilities are not respected exactly. The methods are evaluated using the size of the expected sample overlap, and are compared with their competitors using Monte Carlo simulation. The new methods provide a good coordination degree of two samples, close to the performance of Poisson sampling with permanent random numbers.

  12. Social Annotation Valence: The Impact on Online Informed Consent Beliefs and Behavior.

    Science.gov (United States)

    Balestra, Martina; Shaer, Orit; Okerlund, Johanna; Westendorf, Lauren; Ball, Madeleine; Nov, Oded

    2016-07-20

    Social media, mobile and wearable technology, and connected devices have significantly expanded the opportunities for conducting biomedical research online. Electronic consent to collecting such data, however, poses new challenges when contrasted to traditional consent processes. It reduces the participant-researcher dialogue but provides an opportunity for the consent deliberation process to move from solitary to social settings. In this research, we propose that social annotations, embedded in the consent form, can help prospective participants deliberate on the research and the organization behind it in ways that traditional consent forms cannot. Furthermore, we examine the role of the comments' valence on prospective participants' beliefs and behavior. This study focuses specifically on the influence of annotations' valence on participants' perceptions and behaviors surrounding online consent for biomedical research. We hope to shed light on how social annotation can be incorporated into digitally mediated consent forms responsibly and effectively. In this controlled between-subjects experiment, participants were presented with an online consent form for a personal genomics study that contained social annotations embedded in its margins. Individuals were randomly assigned to view the consent form with positive-, negative-, or mixed-valence comments beside the text of the consent form. We compared participants' perceptions of being informed and having understood the material, their trust in the organization seeking the consent, and their actual consent across conditions. We find that comment valence has a marginally significant main effect on participants' perception of being informed (F2=2.40, P=.07); specifically, participants in the positive condition (mean 4.17, SD 0.94) felt less informed than those in the mixed condition (mean 4.50, SD 0.69, P=.09). Comment valence also had a marginal main effect on the extent to which participants reported trusting the

  13. Social Annotation Valence: The Impact on Online Informed Consent Beliefs and Behavior

    Science.gov (United States)

    Shaer, Orit; Okerlund, Johanna; Westendorf, Lauren; Ball, Madeleine; Nov, Oded

    2016-01-01

    Background Social media, mobile and wearable technology, and connected devices have significantly expanded the opportunities for conducting biomedical research online. Electronic consent to collecting such data, however, poses new challenges when contrasted to traditional consent processes. It reduces the participant-researcher dialogue but provides an opportunity for the consent deliberation process to move from solitary to social settings. In this research, we propose that social annotations, embedded in the consent form, can help prospective participants deliberate on the research and the organization behind it in ways that traditional consent forms cannot. Furthermore, we examine the role of the comments’ valence on prospective participants’ beliefs and behavior. Objective This study focuses specifically on the influence of annotations’ valence on participants’ perceptions and behaviors surrounding online consent for biomedical research. We hope to shed light on how social annotation can be incorporated into digitally mediated consent forms responsibly and effectively. Methods In this controlled between-subjects experiment, participants were presented with an online consent form for a personal genomics study that contained social annotations embedded in its margins. Individuals were randomly assigned to view the consent form with positive-, negative-, or mixed-valence comments beside the text of the consent form. We compared participants’ perceptions of being informed and having understood the material, their trust in the organization seeking the consent, and their actual consent across conditions. Results We find that comment valence has a marginally significant main effect on participants’ perception of being informed (F2=2.40, P=.07); specifically, participants in the positive condition (mean 4.17, SD 0.94) felt less informed than those in the mixed condition (mean 4.50, SD 0.69, P=.09). Comment valence also had a marginal main effect on the

  14. Enterprise Coordination on the Internet

    Directory of Open Access Journals (Sweden)

    Charles Petrie

    2011-02-01

    Full Text Available Enterprises are now connected internally and externally to other Enterprises via the Internet in ways that are increasingly difficult to manage, especially as these interconnections become more dynamic. Current methods of coordinating the effects of change as they propagate through these networks of connections are not likely to scale. What is needed is a new paradigm for how the Internet supports such coordination. Indeed, the Internet should and could provide fundamental coordination functions that are missing today. In this paper, we describe how such a “Coordinated Internet” would work (this paper is an expanded version of [1]. The key functionality of a Coordinated Internet would be that the Internet actively watches what people do (analogous to search completion on desktops today, correlates these activities, and actively notifies people when and how their current tasks affect and are affected by the activities of other people. This would be accomplished by standard coordination functions implemented as a common Internet layer that can be used as a utility by more specialized applications. Such a Coordinated Internet would revolutionize enterprise management, for all enterprises, large and small, corporate and personal. For example, static workflows would become obsolete for all but the the most routine processes. Some solutions provide existence proofs of such a coordination substrate, such as the Redux solution in concurrent engineering, which we describe herein. However, foundational research remains to be done in the new field of Coordination Engineering in order to reach the goal of a future Internet in which coordination functions are fundamental.

  15. A study on configuration-activity relationship of diamminedichloroplatinum (II) by the pseudopotential valence electron-only ab initio calculation method.

    Science.gov (United States)

    Chen, K X; Wu, J A; Ji, R Y

    1987-09-01

    We investigated the cis- and trans-isomers of Pt(NH3)2Cl2 and [Pt(NH3)2]2+ using a quantum chemical non-empirical calculation method, the pseudopotential valence electron-only ab initio method. The electronic structure and electrostatic potential counter maps were in turn determined through the wave functions so obtained. There was a sharp difference between the dipole moments of the cis- and trans-isomers. The electrostatic counter maps of the isomers also had remarkably different features. Based on the interaction between the platinum (II) coordination compound and the base pairs of nucleic acid, the difference in antitumour activity of the isomeric compounds was discussed. It is pointed out that the key factor for antitumour activity is that the platinum (II) coordination compound must be mutually complementary with the target acceptor in both configuration and bonding activity. This mutual-complementary requirement includes a bonding ability of the platinum complex with two negative centers in DNA, so as to form an intrastrand crosslink with two neighbouring guanines.

  16. Keep Meaning in Conversational Coordination

    Directory of Open Access Journals (Sweden)

    Elena Clare Cuffari

    2014-12-01

    Full Text Available Coordination is a widely employed term across recent quantitative and qualitative approaches to intersubjectivity, particularly approaches that give embodiment and enaction central explanatory roles. With a focus on linguistic and bodily coordination in conversational contexts, I review the operational meaning of coordination in recent empirical research and related theorizing of embodied intersubjectivity. This discussion articulates what must be involved in treating linguistic meaning as dynamic processes of coordination. The coordination approach presents languaging as a set of dynamic self-organizing processes and actions on multiple timescales and across multiple modalities that come about and work in certain domains (those jointly constructed in social, interactive, high-order sense-making. These processes go beyond meaning at the level that is available to first-person experience. I take one crucial consequence of this to be the ubiquitously moral nature of languaging with others. Languaging coordinates experience, among other levels of behavior and event. Ethical effort is called for by the automatic autonomy-influencing forces of languaging as coordination.

  17. Chinese geodetic coordinate system 2000

    Institute of Scientific and Technical Information of China (English)

    YANG YuanXi

    2009-01-01

    The basic strategies In establishing the Chinese geodetic coordinate system 2000 have been summarized,including the definition of the coordinate system,the structure of the terrestrial reference frame,the functional and stochastic models involved in the realization of the reference frame as well as the Improvements of the adjustment procedures.First,the fundamental frame of the coordinate system is composed of the permanent GPS tracking network in China which is integrated into the international GPS service stations by combined adjustment,in order to guarantee the consistence between the international terrestrial reference system and the Chinese geodetic coordinate system.Second,the extended frame of the coordinate system is composed of the unified 2000' national GPS network which is Integrated by 6 nationwide GPS networks with more than 2500 stations under the controlling of the fundamental frame.Third,the densified frame is composed of national astronomical geodetic network with nearly 50 thousand stations which was updated by the combined adjustment with the 2000' national GPS network,thus the datum of the national astronomical geodetic network has been unified and the precision greatly improved.By the optimal data fusion method the influences of the datum errors,systematic errors and the outliers in the separated geodetic networks are weakened in the unified Chinese geodetic coordinate frame.The significance in application of the new geodetic coordinate system and the existing problems In the reference frame are described and analyzed.

  18. Positively-valenced stimuli facilitate creative novel metaphoric processes by enhancing medial prefrontal cortical (mPFC activation

    Directory of Open Access Journals (Sweden)

    Karuna eSubramaniam

    2013-04-01

    Full Text Available A metaphor is a figure of speech in which a subject is symbolic of another unrelated object. In the present study, we examined neural patterns associated with both novel unfamiliar and conventional familiar metaphoric processing, and how these patterns are modulated by affective valence. Prior to fMRI scanning, participants received a list of word pairs (novel unfamiliar metaphors as well as conventional familiar metaphors and were asked to denote the valence (positive, negative, or neutral of each word pair. During scanning, participants had to decide whether the word pairs formed meaningful or meaningless expressions. Results indicate that participants were faster and more accurate at deciding that positively-valenced metaphors were meaningful compared to neutral metaphors. These behavioral findings were accompanied by increased activation in the medial prefrontal cortex (mPFC, posterior cingulate cortex (PCC, and the right inferior parietal lobe (IPL. Specifically, positively-valenced novel unfamiliar metaphors elicited activation in these brain regions in addition to the left superior temporal gyrus when compared to neutral novel metaphors. We also found that the mPFC and PCC mediated the processing of positively-valenced metaphors when compared to negatively-valenced metaphors. Positively-valenced conventional metaphors, however, elicited different neural signatures when contrasted with either neutral or negatively-valenced conventional metaphors. Together, our results indicate that positively-valenced stimuli facilitate creative metaphoric processes (specifically novel metaphoric processes by mediating attention and cognitive control processes required for the access, integration and selection of semantic associations via modulation of the mPFC. The present study is important for the development of neural accounts of emotion-cognition interactions required for creativity, language and successful social functioning in general.

  19. Toward a theory of coordinating: Creating coordinating mechanisms in practice

    OpenAIRE

    Jarzabkowski, P; Le, J. K.; Feldman, M. S.

    2012-01-01

    This paper uses a practice perspective to study coordinating as dynamic activities that are continuously created and modified in order to enact organizational relationships and activities. It is based on the case of Servico, an organization undergoing a major restructuring of its value chain in response to a change in government regulation. In our case, the actors iterate between the abstract concept of a coordinating mechanism referred to as end-to-end management and its performance in pract...

  20. Evaluating the Relational Coordination instrument

    DEFF Research Database (Denmark)

    Edwards, Kasper; Lundstrøm, Sanne Lykke

    2014-01-01

    and surgical performance. This has prompted the attention of both practitioners and politicians some of who perceive relational coordination as a means to attain better performance. The relational coordination instrument has been validated as a measure of teamwork from the following perspectives: internal...... consistency, interrater agreement and reliability, structural validity, content validity. However as relational coordination is being used as a diagnostics tool it is important to examine further if the instrument can measure changes. Indeed we need to know how precise and sensitive the instrument is when...

  1. Comparison of ion sites and diffusion paths in glasses obtained by molecular dynamics simulations and bond valence analysis

    OpenAIRE

    Muller, Christian; Zienicke, Egbert; Adams, Stefan; Habasaki, Junko; Maass, Philipp

    2006-01-01

    Based on molecular dynamics simulations of a lithium metasilicate glass we study the potential of bond valence sum calculations to identify sites and diffusion pathways of mobile Li ions in a glassy silicate network. We find that the bond valence method is not well suitable to locate the sites, but allows one to estimate the number of sites. Spatial regions of the glass determined as accessible for the Li ions by the bond valence method can capture up to 90% of the diffusion path. These regio...

  2. The Total Position Spread in mixed-valence compounds: A study on the H4+ model system.

    Science.gov (United States)

    Bendazzoli, Gian Luigi; El Khatib, Muammar; Evangelisti, Stefano; Leininger, Thierry

    2014-04-15

    The behavior of the Total Position Spread (TPS) tensor, which is the second moment cumulant of the total position operator, is investigated in the case of a mixed-valence model system. The system consists of two H2 molecules placed at a distance D. If D is larger than about 4 bohr, the singly ionized system shows a mixed-valence character. It is shown that the magnitude of the TPS has a strong peak in the region of the avoided crossing. We believe that the TPS can be a powerful tool to characterize the behavior of the electrons in realistic mixed-valence compounds.

  3. The special status of sad infant faces: age and valence differences in adults' cortical face processing.

    Science.gov (United States)

    Colasante, Tyler; Mossad, Sarah I; Dudek, Joanna; Haley, David W

    2016-12-20

    Understanding the relative and joint prioritization of age- and valence-related face characteristics in adults' cortical face processing remains elusive because these two characteristics have not been manipulated in a single study of neural face processing. We used electroencephalography to investigate adults' P1, N170, P2 and LPP responses to infant and adult faces with happy and sad facial expressions. Viewing infant vs adult faces was associated with significantly larger P1, N170, P2 and LPP responses, with hemisphere and/or participant gender moderating this effect in select cases. Sad faces were associated with significantly larger N170 responses than happy faces. Sad infant faces were associated with significantly larger N170 responses in the right hemisphere than all other combinations of face age and face valence characteristics. We discuss the relative and joint neural prioritization of infant face characteristics and negative facial affect, and their biological value as distinct caregiving and social cues.

  4. Incremental validity of positive and negative valence in predicting personality disorder.

    Science.gov (United States)

    Simms, Leonard J; Yufik, Tom; Gros, Daniel F

    2010-04-01

    The Big Seven model of personality includes five dimensions similar to the Big Five model as well as two evaluative dimensions—Positive Valence (PV) and Negative Valence (NV)—which reflect extremely positive and negative person descriptors, respectively. Recent theory and research have suggested that PV and NV predict significant variance in personality disorder (PD) above that predicted by the Big Five, but firm conclusions have not been possible because previous studies have been limited to only single measures of PV, NV, and the Big Five traits. In the present study, we replicated and extended previous findings using three markers of all key constructs—including PV, NV, and the Big Five—in a diverse sample of 338 undergraduates. Results of hierarchical multiple regression analyses revealed that PV incrementally predicted Narcissistic and Histrionic PDs above the Big Five and that NV nonspecifically incremented the prediction of most PDs. Implications for dimensional models of personality pathology are discussed.

  5. Traitement des valences verbales dans une grammaire catégorielle du français

    OpenAIRE

    1989-01-01

    Cet article propose de rendre compte dans le cadre d'UCG des phénomènes complexes de la linéarité en français, moyennant deux aménagements : nous postulons en effet que les valences verbales ne sont pas associées a priori à une valeur quelconque pour l'ordre, et qu'elles font partie d'un ensemble plutôt que d'une liste. Le comportement syntaxique des constituants en surface est donc dissocié de l'ordre des valences et régulé par un système de traits similaire à celui de Karttunen (1986) ou d'...

  6. Effects of valence, geometry and electronic correlations on transport in transition metal benzene sandwich molecules

    Science.gov (United States)

    Karolak, M.; Jacob, D.

    2016-11-01

    We study the impact of the valence and the geometry on the electronic structure and transport properties of different transition metal-benzene sandwich molecules bridging the tips of a Cu nanocontact. Our density-functional calculations show that the electronic transport properties of the molecules depend strongly on the molecular geometry which can be controlled by the nanocontact tips. Depending on the valence of the transition metal center certain molecules can be tuned in and out of half-metallic behaviour facilitating potential spintronics applications. We also discuss our results in the framework of an Anderson impurity model, indicating cases where the inclusion of local correlations alters the ground state qualitatively. For Co and V centered molecules we find indications of an orbital Kondo effect.

  7. Stabilization of Th 3+ ions into mixed-valence thorium fluoride

    Science.gov (United States)

    Dubois, Marc; Dieudonné, Belto; Mesbah, Adel; Bonnet, Pierre; El-Ghozzi, Malika; Renaudin, Guillaume; Avignant, Daniel

    2011-01-01

    The unusual oxidation state +3 of the thorium has been stabilized into a lithium containing non-stoichiometric mixed-valence (III/IV) thorium fluorinated phase with formula Li 2+ xTh 12F 50 (0afore mentioned single phase may be considered as an insertion compound. The Li + insertion is accompanied by the simultaneous reduction of a part of the Th 4+ ions, resulting in a mixed-valence III/IV thorium fluoride. The electrochemical insertion of Li + ions into the open channels of the host matrix has been carried out at 60 °C, using an alkylcarbonate PC-LiClO 4 1 M electrolyte. The Li + and Th 3+ contents, both in the starting composition and the Li + inserted ones, were investigated by high resolution solid state 7Li NMR and EPR, respectively.

  8. Vertical metaphor with motion and judgment: a valenced congruency effect with fluency.

    Science.gov (United States)

    Freddi, Sébastien; Cretenet, Joël; Dru, Vincent

    2014-09-01

    Following metaphorical theories of affect, several research studies have shown that the spatial cues along a vertical dimension are useful in qualifying emotional experience (HAPPINESS is UP, SADNESS is DOWN). Three experiments were conducted to examine the role of vertical motion in affective judgment. They showed that positive stimuli moving UPWARD were evaluated more positively than those moving DOWNWARD, whereas negative stimuli moving DOWNWARD were evaluated as less negative than those moving UPWARD. They showed a valenced congruency effect, but an alternative hypothesis in terms of MORE is UP and LESS is DOWN was also examined. Finally, fluency mechanisms were investigated to confirm that relationships between affect and verticality were in accordance with a valenced congruency effect.

  9. Epitaxial growth and electronic properties of mixed valence YbAl3 thin films

    Science.gov (United States)

    Chatterjee, Shouvik; Sung, Suk Hyun; Baek, David J.; Kourkoutis, Lena F.; Schlom, Darrell G.; Shen, Kyle M.

    2016-07-01

    We report the growth of thin films of the mixed valence compound YbAl3 on MgO using molecular-beam epitaxy. Employing an aluminum buffer layer, epitaxial (001) films can be grown with sub-nm surface roughness. Using x-ray diffraction, in situ low-energy electron diffraction, and aberration-corrected scanning transmission electron microscopy, we establish that the films are ordered in the bulk as well as at the surface. Our films show a coherence temperature of 37 K, comparable to that reported for bulk single crystals. Photoelectron spectroscopy reveals contributions from both f13 and f12 final states establishing that YbAl3 is a mixed valence compound and shows the presence of a Kondo Resonance peak near the Fermi-level.

  10. Trait Anxiety Is Associated with Negative Interpretations When Resolving Valence Ambiguity of Surprised Faces.

    Science.gov (United States)

    Park, Gewnhi; Vasey, Michael W; Kim, Grace; Hu, Dixie D; Thayer, Julian F

    2016-01-01

    The current research examines whether trait anxiety is associated with negative interpretation bias when resolving valence ambiguity of surprised faces. To further isolate the neuro-cognitive mechanism, we presented angry, happy, and surprised faces at broad spatial frequency (BSF), high spatial frequency (HSF), and low spatial frequency (LSF) and asked participants to determine the valence of each face. High trait anxiety was associated with more negative interpretations of BSF (i.e., intact) surprised faces. However, the modulation of trait anxiety on the negative interpretation of surprised faces disappeared at HSF and LSF. The current study provides evidence that trait anxiety modulates negative interpretations of BSF surprised faces. However, the negative interpretation of LSF surprised faces appears to be a robust default response that occurs regardless of individual differences in trait anxiety.

  11. Trait anxiety is associated with negative interpretations when resolving valence ambiguity of surprised faces

    Directory of Open Access Journals (Sweden)

    Gewnhi Park

    2016-08-01

    Full Text Available The current research examines whether trait anxiety is associated with negative interpretation bias when resolving valence ambiguity of surprised faces. To further isolate the neuro-cognitive mechanism, we presented angry, happy, and surprised faces at broad, high, and low spatial frequency and asked participants to determine the valence of each face. High trait anxiety was associated with more negative interpretations of broad spatial frequency (i.e., intact surprised faces. However, the modulation of trait anxiety on the negative interpretation of surprised faces disappeared at high and low spatial frequencies. The current study provides evidence that trait anxiety modulates negative interpretations of broad spatial frequency surprised faces. However, the negative interpretation of low spatial frequency surprised faces appears to be a robust default response that occurs regardless of individual differences in trait anxiety.

  12. Continuum limit of overlap valence quarks on a twisted mass sea

    Energy Technology Data Exchange (ETDEWEB)

    Cichy, Krzysztof [Adam Mickiewicz Univ., Poznan (Poland). Faculty of Physics; Herdoiza, Gregorio [DESY, Zeuthen (Germany). John von Neumann-Institut fuer Computing NIC; Univ. Autonoma de Madrid (Spain). Dept. de Fisica Teorica; Jansen, Karl [DESY, Zeuthen (Germany). John von Neumann-Institut fuer Computing NIC

    2010-12-15

    We study a lattice QCD mixed action with overlap valence quarks on two flavours of Wilson maximally twisted mass sea quarks. Employing three different matching conditions to relate both actions to each other, we investigate the continuum limit by using three values of the lattice spacing ranging from a{approx}0.05 fm to 0.08 fm. A particular emphasis is put on the effect on physical observables of the topological zero modes appearing in the valence overlap operator. We estimate the region of parameter space where the contribution from these zero modes is sufficiently small such that their effects can be safely controlled and a restoration of unitarity of the mixed action in the continuum limit is reached. (orig.)

  13. The influence of ligand valency on aggregation mechanisms for inhibiting bacterial toxins.

    Science.gov (United States)

    Sisu, Cristina; Baron, Andrew J; Branderhorst, Hilbert M; Connell, Simon D; Weijers, Carel A G M; de Vries, Renko; Hayes, Edward D; Pukin, Aliaksei V; Gilbert, Michel; Pieters, Roland J; Zuilhof, Han; Visser, Gerben M; Turnbull, W Bruce

    2009-01-26

    Divalent and tetravalent analogues of ganglioside GM1 are potent inhibitors of cholera toxin and Escherichia coli heat-labile toxin. However, they show little increase in inherent affinity when compared to the corresponding monovalent carbohydrate ligand. Analytical ultracentrifugation and dynamic light scattering have been used to demonstrate that the multivalent inhibitors induce protein aggregation and the formation of space-filling networks. This aggregation process appears to arise when using ligands that do not match the valency of the protein receptor. While it is generally accepted that multivalency is an effective strategy for increasing the activity of inhibitors, here we show that the valency of the inhibitor also has a dramatic effect on the kinetics of aggregation and the stability of intermediate protein complexes. Structural studies employing atomic force microscopy have revealed that a divalent inhibitor induces head-to-head dimerization of the protein toxin en route to higher aggregates.

  14. Multidimensional X-Ray Spectroscopy of Valence and Core Excitations in Cysteine

    CERN Document Server

    Biggs, Jason D; Healion, Daniel; Mukamel, Shaul

    2013-01-01

    Several nonlinear spectroscopy experiments which employ broadband x-ray pulses to probe the coupling between localized core and delocalized valence excitation are simulated for the amino acid cysteine at the K-edges of oxygen and nitrogen and the K and L-edges of sulfur. We focus on two dimensional (2D) and 3D signals generated by two- and three-pulse stimulated x-ray Raman spectroscopy (SXRS) with frequency-dispersed probe. We show how the four-pulse x-ray signals $\\boldsymbol{k}_\\mathrm{I}=-\\boldsymbol{k}_1+\\boldsymbol{k}_2+\\boldsymbol{k}_3$ and $\\boldsymbol{k}_\\mathrm{II}=\\boldsymbol{k}_1-\\boldsymbol{k}_2+\\boldsymbol{k}_3$ can give new 3D insight into the SXRS signals. The coupling between valence- and core-excited states can be visualized in three dimensional plots, revealing the origin of the polarizability that controls the simpler pump-probe SXRS signals.

  15. The new Resonating Valence Bond Method for ab-initio Electronic Simulations

    CERN Document Server

    Sorella, Sandro

    2013-01-01

    The Resonating Valence Bond theory of the chemical bond was introduced soon after the discovery of quantum mechanics and has contributed to explain the role of electron correlation within a particularly simple and intuitive approach where the chemical bond between two nearby atoms is described by one or more singlet electron pairs. In this chapter Pauling's resonating valence bond theory of the chemical bond is revisited within a new formulation, introduced by P.W. Anderson after the discovery of High-Tc superconductivity. It is shown that this intuitive picture of electron correlation becomes now practical and efficient, since it allows us to faithfully exploit the locality of the electron correlation, and to describe several new phases of matter, such as Mott insulators, High-Tc superconductors, and spin liquid phases.

  16. Norms of valence, arousal, dominance, and age of acquisition for 4,300 Dutch words.

    Science.gov (United States)

    Moors, Agnes; De Houwer, Jan; Hermans, Dirk; Wanmaker, Sabine; van Schie, Kevin; Van Harmelen, Anne-Laura; De Schryver, Maarten; De Winne, Jeffrey; Brysbaert, Marc

    2013-03-01

    This article presents norms of valence/pleasantness, activity/arousal, power/dominance, and age of acquisition for 4,300 Dutch words, mainly nouns, adjectives, adverbs, and verbs. The norms are based on ratings with a 7-point Likert scale by independent groups of students from two Belgian (Ghent and Leuven) and two Dutch (Rotterdam and Leiden-Amsterdam) samples. For each variable, we obtained high split-half reliabilities within each sample and high correlations between samples. In addition, the valence ratings of a previous, more limited study (Hermans & De Houwer, Psychologica Belgica, 34:115-139, 1994) correlated highly with those of the present study. Therefore, the new norms are a valuable source of information for affective research in the Dutch language.

  17. Valence orbitals of W(CO)6 using electron momentum spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Shi Le-Lei; Liu Kun; Luo Zhi-Hong; Ning Chuan-Gang; Deng Jing-Kang

    2011-01-01

    The binding energy spectra and the momentum distributions of the outer valence orbitals of W(CO)6 have been studied by using electron momentum spectroscopy as well as non-relativistic,scalar relativistic and spin-orbital relativistic DFT-B3LYP calculations.The experimental momentum profiles of the outer valence orbitals obtained with the impact energies of 1200 eV and 2400 eV were compared with various theoretical calculation results.The relativistic calculations could provide better descriptions for the experimental momentum distributions than the non-relativistic ones.Moreover,a new ordering of orbitals 10t1u,3t2g,and 7eg,i.e.,10t1u < 3t2g <7eg <10a1g,is established in this work.

  18. Localization of the valence electron of endohedrally confined hydrogen, lithium and sodium in fullerene cages

    CERN Document Server

    Cuestas, Eloisa

    2016-01-01

    The localization of the valence electron of $H$, $Li$ and $Na$ atoms enclosed by three different fullerene molecules is studied. The structure of the fullerene molecules is used to calculate the equilibrium position of the endohedrally atom as the minimum of the classical $(N+1)$-body Lennard-Jones potential. Once the position of the guest atom is determined, the fullerene cavity is modeled by a short range attractive shell according to molecule symmetry, and the enclosed atom is modeled by an effective one-electron potential. In order to examine whether the endohedral compound is formed by a neutral atom inside a neutral fullerene molecule $X@C_{N}$ or if the valence electron of the encapsulated atom localizes in the fullerene giving rise to a state with the form $X^{+}@C_{N}^{-}$, we analyze the electronic density, the projections onto free atomic states, and the weights of partial angular waves.

  19. A valence bond study of three-center four-electron pi bonding: electronegativity vs electroneutrality.

    Science.gov (United States)

    DeBlase, Andrew; Licata, Megan; Galbraith, John Morrison

    2008-12-18

    Three-center four-electron (3c4e) pi bonding systems analogous to that of the ozone molecule have been studied using modern valence bond theory. Molecules studied herein consist of combinations of first row atoms C, N, and O with the addition of H atoms where appropriate in order to preserve the 3c4e pi system. Breathing orbital valence bond (BOVB) calculations were preformed at the B3LYP/6-31G**-optimized geometries in order to determine structural weights, pi charge distributions, resonance energies, and pi bond energies. It is found that the most weighted VB structure depends on atomic electronegativity and charge distribution, with electronegativity as the dominant factor. By nature, these systems are delocalized, and therefore, resonance energy is the main contributor to pi bond energies. Molecules with a single dominant VB structure have low resonance energies and therefore low pi bond energies.

  20. Analysis of Valence Electron Structure of RE in Solid Solution in Medium and Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    朱莹光; 刘艳; 刘志林; 刘伟东

    2004-01-01

    According to EET theory,the valence electron structures of RE in the solid solution of austenite,pearlite and martensite were calculated.The influence of RE in solid solution on phase transformation of pearlite and recrystallization of martensite was explained by the valence electron structure data of phases.Calculating results indicate that C element is favorite to enhance the number of RE in the solid solution.RE in the solute solution shortens the incubation period of proeutectoid ferrite,increases its quantity and carbon content,decreases the quantity of pearlite and thickness of its lamellas and lamellar spacing,then the strength and hardness of pearlite are improved and granular pearlite can be obtained.RE dissolved in martensite intensifies martensite,enhances tempering stability of martensite,increases its recrystallization temperature and prolongs the holding time needed during tempering.

  1. Valence Control of Ce Ions in Cerium-substituted Yttrium Iron Garnet

    Institute of Scientific and Technical Information of China (English)

    SONG Fengbing; LI Qiang; ZHONG Zhifeng

    2005-01-01

    Cerium-substituted yttrium iron garnet(CexY3-xFe5O12, Ce∶YIG) was prepared via coprecipitation. The structure, morphology, valence state and constituent of Ce ions were investigated respectively. X-ray powder diffraction(XRD) analysis shows that Ce∶YIG was of single cubic YIG phase. The result of X-ray photoelectron spectroscopy(XPS) indicates the Ce ions in Ce∶YIG were in the state of trivalence. Scanning electron microscope(SEM) demonstrates the conglobation of Ce∶YIG particles about 0.2μm scale.The magnetic properties were studied by a vibrating sample magnetometer(VSM) and the result exhibits that substitution of Ce3+ changes the magnetic parameters of YIG. The effects of doping content of Ce ions and synthesis temperature on valence control were discussed in detail.

  2. Continuum Limit of Overlap Valence Quarks on a Twisted Mass Sea

    CERN Document Server

    Cichy, Krzysztof; Jansen, Karl

    2010-01-01

    We study a lattice QCD mixed action with overlap valence quarks on two flavours of Wilson maximally twisted mass sea quarks. Employing three different matching conditions to relate both actions to each other, we investigate the continuum limit by using three values of the lattice spacing ranging from 0.05 fm to 0.08 fm. A particular emphasis is put on the effect on physical observables of the topological zero modes appearing in the valence overlap operator. We estimate the region of parameter space where the contribution from these zero modes is sufficiently small such that their effects can be safely controlled and a restoration of unitarity of the mixed action in the continuum limit is reached.

  3. Exchange-correlation energy of a hole gas including valence band coupling

    Science.gov (United States)

    Bobbert, P. A.; Wieldraaijer, H.; van der Weide, R.; Kemerink, M.; Koenraad, P. M.; Wolter, J. H.

    1997-08-01

    We have calculated an accurate exchange-correlation energy of a hole gas, including the complexities related to the valence band coupling as occurring in semiconductors like GaAs, but excluding the band warping. A parametrization for the dependence on the density and the ratio between light- and heavy-hole masses is given. We apply our results to a hole gas in an AlxGa1-xAs/GaAs/AlxGa1-xAs quantum well and calculate the two-dimensional band structure and the band-gap renormalization. The inclusion of the valence band coupling in the calculation of the exchange-correlation potentials for holes and electrons leads to a much better agreement between theoretical and experimental data than when it is omitted.

  4. Macaque cardiac physiology is sensitive to the valence of passively viewed sensory stimuli.

    Directory of Open Access Journals (Sweden)

    Eliza Bliss-Moreau

    Full Text Available Autonomic nervous system activity is an important component of affective experience. We demonstrate in the rhesus monkey that both the sympathetic and parasympathetic branches of the autonomic nervous system respond differentially to the affective valence of passively viewed video stimuli. We recorded cardiac impedance and an electrocardiogram while adult macaques watched a series of 300 30-second videos that varied in their affective content. We found that sympathetic activity (as measured by cardiac pre-ejection period increased and parasympathetic activity (as measured by respiratory sinus arrhythmia decreased as video content changes from positive to negative. These findings parallel the relationship between autonomic nervous system responsivity and valence of stimuli in humans. Given the relationship between human cardiac physiology and affective processing, these findings suggest that macaque cardiac physiology may be an index of affect in nonverbal animals.

  5. Emotional experience in daily life: valence, variability, and rate of change.

    Science.gov (United States)

    Eaton, L G; Funder, D C

    2001-12-01

    Measurements of 3 basic affective phenomena--valence of emotion, intraindividual variability, and rate of change--were derived from self-reports of emotion gathered from 123 participants (68 females, 55 males) sampled 4 times daily over 8 days. Self-reports and acquaintances' descriptions of personality were also obtained. The 3 emotion variables were not significantly intercorrelated and yielded different personality correlates. Valence of emotion positively correlated with extraversion, intraindividual variability with repression, and rate of change with fearfulness and hostility toward others, but not all results were consistent across gender. It is suggested that future research pay increased attention to patterns of emotional change over time and to the relations between gender and emotional experience.

  6. πK scattering in full QCD with domain-wall valence quarks

    NARCIS (Netherlands)

    Beane, Silas R.; Bedaque, Paulo F.; Luu, Thomas C.; Orginos, Kostas; Pallante, Elisabetta; Parreño, Assumpta; Savage, Martin J.

    2006-01-01

    We calculate the π+K+ scattering length in fully-dynamical lattice QCD with domain-wall valence quarks on MILC lattices with rooted staggered sea-quarks at a lattice spacing of b = 0.125 fm, lattice spatial size of L = 2.5 fm and at pion masses of mπ ~ 290, 350, 490 and 600 MeV. The lattice data, an

  7. The mechanism of valence-space metaphors: ERP evidence for affective word processing.

    Science.gov (United States)

    Xie, Jiushu; Wang, Ruiming; Chang, Song

    2014-01-01

    Embodied cognition contends that the representation and processing of concepts involve perceptual, somatosensory, motoric, and other physical re-experiencing information. In this view, affective concepts are also grounded in physical information. For instance, people often say "feeling down" or "cheer up" in daily life. These phrases use spatial information to understand affective concepts. This process is referred to as valence-space metaphor. Valence-space metaphors refer to the employment of spatial information (lower/higher space) to elaborate affective concepts (negative/positive concepts). Previous studies have demonstrated that processing affective words affects performance on a spatial detection task. However, the mechanism(s) behind this effect remain unclear. In the current study, we hypothesized that processing affective words might produce spatial information. Consequently, spatial information would affect the following spatial cue detection/discrimination task. In Experiment 1, participants were asked to remember an affective word. Then, they completed a spatial cue detection task while event-related potentials were recorded. The results indicated that the top cues induced enhanced amplitude of P200 component while participants kept positive words relative to negative words in mind. On the contrary, the bottom cues induced enhanced P200 amplitudes while participants kept negative words relative to positive words in mind. In Experiment 2, we conducted a behavioral experiment that employed a similar paradigm to Experiment 1, but used arrows instead of dots to test the attentional nature of the valence-space metaphor. We found a similar facilitation effect as found in Experiment 1. Positive words facilitated the discrimination of upper arrows, whereas negative words facilitated the discrimination of lower arrows. In summary, affective words might activate spatial information and cause participants to allocate their attention to corresponding locations

  8. Valence Fluctuations in La2-xSrxCuO4

    NARCIS (Netherlands)

    Groot, R.A. de; Gutfreund, H.; Weger, M.

    1987-01-01

    Ab-initio electronic band structure calculations are presented for the perovskite La2CuO4 and for this material doped with Sr for a supercell of composition La3SrCu2O8. This material is close to the high Tc superconductor La2-xSrxCuO4 discovered recently. The Sr doping gives rise to strong valence f

  9. Application of Koopmans' theorem for density functional theory to full valence-band photoemission spectroscopy modeling.

    Science.gov (United States)

    Li, Tsung-Lung; Lu, Wen-Cai

    2015-10-05

    In this work, Koopmans' theorem for Kohn-Sham density functional theory (KS-DFT) is applied to the photoemission spectra (PES) modeling over the entire valence-band. To examine the validity of this application, a PES modeling scheme is developed to facilitate a full valence-band comparison of theoretical PES spectra with experiments. The PES model incorporates the variations of electron ionization cross-sections over atomic orbitals and a linear dispersion of spectral broadening widths. KS-DFT simulations of pristine rubrene (5,6,11,12-tetraphenyltetracene) and potassium-rubrene complex are performed, and the simulation results are used as the input to the PES models. Two conclusions are reached. First, decompositions of the theoretical total spectra show that the dissociated electron of the potassium mainly remains on the backbone and has little effect on the electronic structures of phenyl side groups. This and other electronic-structure results deduced from the spectral decompositions have been qualitatively obtained with the anionic approximation to potassium-rubrene complexes. The qualitative validity of the anionic approximation is thus verified. Second, comparison of the theoretical PES with the experiments shows that the full-scale simulations combined with the PES modeling methods greatly enhance the agreement on spectral shapes over the anionic approximation. This agreement of the theoretical PES spectra with the experiments over the full valence-band can be regarded, to some extent, as a collective validation of the application of Koopmans' theorem for KS-DFT to valence-band PES, at least, for this hydrocarbon and its alkali-adsorbed complex. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. $B_{(s)}\\to D_{(s)}$ semileptonic decays with NRQCD-HISQ valence quarks

    CERN Document Server

    Monahan, Christopher J; Bouchard, Chris M; Lepage, G Peter; Shigemitsu, Junko

    2016-01-01

    We present a calculation of the form factors, $f_0$ and $f_+$, for the $B_{(s)} \\to D_{(s)}$ semileptonic decays. Our work uses the MILC $n_f=2+1$ AsqTad configurations with NRQCD and HISQ valence quarks at four values of the momentum transfer $q^2$. We include results for the chiral-continuum extrapolations of the scalar and vector form factors.

  11. Inelastic neutron scattering on a mixed-valence dodecanuclear polyoxovanadate cluster

    CERN Document Server

    Basler, R; Andrés, H; Güdel, H U; Koegerler, P; Krickemeier, E; Bögge, H; Müller, A; Mutka, H

    2002-01-01

    The magnetic exchange interactions in the mixed-valence dodecanuclear polyoxovanadate cluster compound (NHEt sub 3) sub 4 [V sub 1 sub 2 As sub 8 O sub 4 sub 0 (H sub 2 O)] x H sub 2 O were investigated by a detailed inelastic neutron scattering study using cold neutrons. The data show clear evidence for the presence of a magnetic anisotropy within the cluster. Exchange parameters are accurately determined. (orig.)

  12. Retrospectives, current valences and prospective dimensions of research at the Academy of Public Administration

    Directory of Open Access Journals (Sweden)

    Aurel SÎMBOTEANU

    2016-12-01

    Full Text Available The present study is an attempt to identify the social determinants, which initiated and facilitated the content and evolution of the scientific research of the administrative phenomenon in the Republic of Moldova after the declaration of independence. It also elucidates the current valences and perspectives of this activity in the context of the provisions of the recently adopted Research Strategy of the Academy of Public Administration for the period 2016-2020.

  13. Arousal, valence, and the uncanny valley: Psychophysiological and self-report findings.

    Directory of Open Access Journals (Sweden)

    Marcus eCheetham

    2015-07-01

    Full Text Available The main prediction of the Uncanny Valley Hypothesis (UVH is that observation of humanlike characters that are difficult to distinguish from the human counterpart will evoke a state of negative affect. Well-established electrophysiological (late positive potential [LPP] and facial electromyography [EMG] and self-report (Self-Assessment Manikin; SAM indices of valence and arousal, i.e., the primary orthogonal dimensions of affective experience, were used to test this prediction by examining affective experience in response to categorically ambiguous compared with unambiguous avatar and human faces (N=30. LPP and EMG provided direct psychophysiological indices of affective state during passive observation and the SAM provided self-reported indices of affective state during explicit cognitive evaluation of static facial stimuli. The faces were drawn from well-controlled morph continua representing the UVH’ dimension of human likeness (DHL. The results provide no support for the notion that category ambiguity along the DHL is specifically associated with enhanced experience of negative affect. On the contrary, the LPP and SAM-based measures of arousal and valence indicated a general increase in negative affective state (i.e., enhanced arousal and negative valence with greater morph distance from the human end of the DHL. A second sample (N=30 produced the same finding, using an ad hoc self-rating scale of feelings of familiarity, i.e., an oft-used measure of affective experience along the UVH' familiarity dimension. In conclusion, this multi-method approach using well-validated psychophysiological and self-rating indices of arousal and valence rejects - for passive observation and for explicit affective evaluation of static faces - the main prediction of the UVH.

  14. Personality modulates the effects of emotional arousal and valence on brain activation

    OpenAIRE

    Kehoe, Elizabeth G.; Toomey, John M.; Balsters, Joshua H.; Bokde, Arun L.W.

    2011-01-01

    The influence of personality on the neural correlates of emotional processing is still not well characterized. We investigated the relationship between extraversion and neuroticism and emotional perception using functional magnetic resonance imaging (fMRI) in a group of 23 young, healthy women. Using a parametric modulation approach, we examined how the blood oxygenation level dependent (BOLD) signal varied with the participants’ ratings of arousal and valence, and whether levels of extravers...

  15. Killig-Yano Tensors of Valence-2 in the Standart Kaluza-Klein Theory

    CERN Document Server

    Nurbaki, Ali Nur

    2011-01-01

    This work is constructed on two main concepts: Killing-Yano symmetry and the Kaluza-Klein theory. Those concepts are reviewed in the first three chapters. In the fourth chapter firstly Killing-Yano equations of valence-2 are obtained for a general 5-dimensional metric and then reduced for the Minkowski metric. It is seen that in order to save the existence of Killing-Yano tensors with the fifth components some conditions must be satisfied

  16. Pseudotetragonal structure of Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50): the first mixed valence cerium fluoride.

    Science.gov (United States)

    Renaudin, Guillaume; Dieudonné, Belto; Avignant, Daniel; Mapemba, Elise; El-Ghozzi, Malika; Fleutot, Solène; Martinez, Hervé; Cerný, Radovan; Dubois, Marc

    2010-01-18

    The crystal structure of the new Li(5.5)Ce(12)F(50) compound has been fully characterized by single-crystal and synchrotron powder X-ray diffraction. An accurate pseudotetragonal structure was described in the monoclinic P2(1) space group with 68 independent crystallographic sites. The Li(5.5)Ce(12)F(50) composition belongs to the Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50) solid solution. Its structure consists of an opened fluorine framework where a channel network allows the intercalation of relatively mobile lithium cations, inducing the formation of the mixed-valence cerium (the intercalation of Li(+) leads to the reduction of a part of Ce(4+) to Ce(3+)). One part of the lithium ions, necessary for the electroneutrality of the tetravalent equivalent cerium fluoride (Li(2)Ce(12)F(50) composition), is in a locked fluorine polyhedron. Only the supplementary x amount of lithium is able to be exchanged in Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50). The structure of Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50) is a rearrangement, due to lithium intercalation, of the base CeF(4) structure. Bond valence calculation on Ce sites, Ce coordination polyhedra volumes, and a calculated Ce cationic radius give the indication of a partial long-range ordering of trivalent and tetravalent cerium cations in specific slabs of the structure. (7)Li NMR spectroscopy and XPS analyses have confirmed all of the structure details.

  17. Valence-delocalization of the mixed-valence oxo-centered trinuclear iron propionates [Fe{2/III}FeIIO(C2H5CO2)6(py)3] npy; n=0, 1.5

    Science.gov (United States)

    Nakamoto, Tadahiro; Katada, Motomi; Kawata, Satoshi; Kitagawa, Susumu; Sano, Hirotoshi; Konno, Michiko

    1994-12-01

    Mixed-valence trinuclear iron propionates [Fe{2/III}FeIIO(C2H5CO2)6(py)3]npy, where n=0, 1.5, were synthesized and the structure of the pyridine-solvated complex was determined by single-crystal X-ray diffraction. Mössbauer spectra of the solvated propionate complex showed a temperature-dependent mixed-valence state related to phase transitions, reaching an almost delocalized valence state at room temperature. On the other hand, the non-solvated propionate showed a remarkable change of the spectral shape related to a phase transition, remaining in a localized valence state at higher temperatures up to room temperature.

  18. Facial feedback affects valence jugdments of dynamic and static emotional expressions

    Directory of Open Access Journals (Sweden)

    Sylwia eHyniewska

    2015-03-01

    Full Text Available The ability to judge others’ emotions is required for the establishment and maintenance of smooth interactions in a community. Several lines of evidence suggest that the attribution of meaning to a face is influenced by the facial actions produced by an observer during the observation of a face. However, empirical studies testing causal relationships between observers’ facial actions and emotion judgments have reported mixed findings. This study is the first to measure emotion judgments in terms of valence and arousal dimensions while comparing dynamic versus static presentations of facial expressions. We presented pictures and videos of facial expressions of anger and happiness. Participants (N = 36 were asked to differentiate between the gender of faces by activating the corrugator supercilii muscle (brow lowering and zygomaticus major muscle (cheek raising. They were also asked to evaluate the internal states of the stimuli using the affect grid while maintaining the facial action until they finished responding. The cheek-raising condition increased the attributed valence scores compared with the brow-lowering condition. This effect of facial actions was observed for static as well as for dynamic facial expressions. These data suggest that facial feedback mechanisms contribute to the judgment of the valence of emotional facial expressions.

  19. Magnetic-field-induced valence transition in rare-earth systems

    Indian Academy of Sciences (India)

    G Gangadhar Reddy; A Ramakanth; S K Ghatak

    2002-05-01

    The magnetic-field-induced valence transition in rare-earth systems has been investigated using the periodic Anderson model supplemented by the Falicov–Kimball term. This model has been solved by first decoupling the Falicov–Kimball term as proposed by Khomskii and Koharjan and then taking the limit of infinite intra-site Coulomb repulsion. The valence transition both in the absence and in the presence of magnetic field as a function of temperature is studied. It has been found that the system makes transition from non-magnetic to magnetic state when the magnetic field increases beyond a critical value c. The phase boundary defined in terms of reduced field c()/c(0) and reduced temperature /v (v being the valence transition temperature in the absence of field) is almost independent of the position of the localized level. The results are in qualitative agreement with experimental observations in Yb- and Eu-compounds.

  20. Embodied simulation as part of affective evaluation processes: task dependence of valence concordant EMG activity.

    Science.gov (United States)

    Weinreich, André; Funcke, Jakob Maria

    2014-01-01

    Drawing on recent findings, this study examines whether valence concordant electromyography (EMG) responses can be explained as an unconditional effect of mere stimulus processing or as somatosensory simulation driven by task-dependent processing strategies. While facial EMG over the Corrugator supercilii and the Zygomaticus major was measured, each participant performed two tasks with pictures of album covers. One task was an affective evaluation task and the other was to attribute the album covers to one of five decades. The Embodied Emotion Account predicts that valence concordant EMG is more likely to occur if the task necessitates a somatosensory simulation of the evaluative meaning of stimuli. Results support this prediction with regard to Corrugator supercilii in that valence concordant EMG activity was only present in the affective evaluation task but not in the non-evaluative task. Results for the Zygomaticus major were ambiguous. Our findings are in line with the view that EMG activity is an embodied part of the evaluation process and not a mere physical outcome.

  1. Post-determined emotion: motor action retrospectively modulates emotional valence of visual images.

    Science.gov (United States)

    Sasaki, Kyoshiro; Yamada, Yuki; Miura, Kayo

    2015-04-22

    Upward and downward motor actions influence subsequent and ongoing emotional processing in accordance with a space-valence metaphor: positive is up/negative is down. In this study, we examined whether upward and downward motor actions could also affect previous emotional processing. Participants were shown an emotional image on a touch screen. After the image disappeared, they were required to drag a centrally located dot towards a cued area, which was either in the upper or lower portion of the screen. They were then asked to rate the emotional valence of the image using a 7-point scale. We found that the emotional valence of the image was more positive when the cued area was located in the upper portion of the screen. However, this was the case only when the dragging action was required immediately after the image had disappeared. Our findings suggest that when somatic information that is metaphorically associated with an emotion is linked temporally with a visual event, retrospective emotional integration between the visual and somatic events occurs. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  2. Reprint of "Affective picture processing as a function of preceding picture valence: an ERP analysis".

    Science.gov (United States)

    Schupp, Harald T; Schmälzle, Ralf; Flaisch, Tobias; Weike, Almut I; Hamm, Alfons O

    2013-03-01

    Event-related brain potential (ERP) studies consistently revealed that a relatively early (early posterior negativity; EPN) and a late (late positive potential; LPP) ERP component differentiate between emotional and neutral picture stimuli. Two studies examined the processing of emotional stimuli when preceded either by pleasant, neutral, or unpleasant context images. In both studies, distinct streams of six pictures were shown. In Study 1, hedonic context was alternated randomly across the 180 picture streams. In Study 2, hedonic context sequences were blocked, resulting in 60 preceding sequences of pleasant, neutral, and unpleasant context valence, respectively. The main finding was that the valence of the preceding picture sequence had no significant effect on the emotional modulation of the EPN and LPP components. However, previous results were replicated in that emotional stimulus processing was associated with larger EPN and LPP components as compared to neutral pictures. These findings suggest that the prioritized processing of emotional stimuli is primarily driven by the valence of the current picture. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Effective charges, the valence p-n interaction, and the IBM

    Energy Technology Data Exchange (ETDEWEB)

    Casten, R.F. (Brookhaven National Lab., Upton, NY (United States)); Wolf, A. (Brookhaven National Lab., Upton, NY (United States) Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev)

    1992-01-01

    There are three recent themes in nuclear structure that come together in an interesting and useful way via the concept of effective charges and the framework of the IBM. These three concepts are the importance of dynamical symmetries in describing nuclear structure and the benefits that accrue from their exploitation, secondly, the critical role of the p-n interaction in the onset and development of collectivity in nuclei, and, thirdly, the importance of the valence nucleons in determining structure and its evolution. We will illustrate this by showing that the interpretation of measured B(E2) values in the context of the dynamical symmetries of the IBM leads to new insights into the meaning of effective charges and offers new avenues to understand the role of the proton-neutron (p-n) interaction in modulating the nature of the valence space and the growth of collectivity. In particular, we will show that effective charges in valence models, such as the IBM, can be interpreted in terms of derivatives of the collectivity of the low lying levels, that is, as measures of the rate of change of collectivity as the proton and neutron numbers vary. This paper is based on recent work by the authors.

  4. Effective charges, the valence p-n interaction, and the IBM

    Energy Technology Data Exchange (ETDEWEB)

    Casten, R.F. [Brookhaven National Lab., Upton, NY (United States); Wolf, A. [Brookhaven National Lab., Upton, NY (United States)]|[Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev

    1992-10-01

    There are three recent themes in nuclear structure that come together in an interesting and useful way via the concept of effective charges and the framework of the IBM. These three concepts are the importance of dynamical symmetries in describing nuclear structure and the benefits that accrue from their exploitation, secondly, the critical role of the p-n interaction in the onset and development of collectivity in nuclei, and, thirdly, the importance of the valence nucleons in determining structure and its evolution. We will illustrate this by showing that the interpretation of measured B(E2) values in the context of the dynamical symmetries of the IBM leads to new insights into the meaning of effective charges and offers new avenues to understand the role of the proton-neutron (p-n) interaction in modulating the nature of the valence space and the growth of collectivity. In particular, we will show that effective charges in valence models, such as the IBM, can be interpreted in terms of derivatives of the collectivity of the low lying levels, that is, as measures of the rate of change of collectivity as the proton and neutron numbers vary. This paper is based on recent work by the authors.

  5. Voluntary or Mandatory? The Valence Framing Effect of Attitudes Regarding HPV Vaccination.

    Science.gov (United States)

    Gesser-Edelsburg, Anat; Walter, Nathan; Shir-Raz, Yaffa; Green, Manfred S

    2015-01-01

    This study addresses the issue of valence framing effect in the context of immunization, a preventive behavior often addressed by the equation of benefit versus risk. The authors examined how framing (support vs. oppose) the issue of HPV vaccination in Israel's immunization routine affects attitudes regarding vaccine regulations. The study also examined issue involvement as a moderator of valence framing effect. The results demonstrate that participants in the positive framing condition tended to express greater support for voluntary immunization than participants in the negative framing condition (77.5% and 48.5%, respectively). Among those who supported the mandatory HPV immunization policy, the negative framing condition was more prominent than the positive condition (51.5% and 22.5%, respectively). The analysis of interaction between valence framing and issue involvement showed that the latter tends to moderate the direct effect of framing on attitudes towards vaccination. Findings indicate that even attitudes towards such consequential preventive behaviors as vaccination could be affected by different framing of the issue, especially for those who are less involved. Implications of predilection for freedom of choice regarding vaccination are also discussed.

  6. Di- and Trinuclear Mixed-Valence Copper Amidinate Complexes from Reduction of Iodine.

    Science.gov (United States)

    Lane, Andrew C; Barnes, Charles L; Antholine, William E; Wang, Denan; Fiedler, Adam T; Walensky, Justin R

    2015-09-08

    Molecular examples of mixed-valence copper complexes through chemical oxidation are rare but invoked in the mechanism of substrate activation, especially oxygen, in copper-containing enzymes. To examine the cooperative chemistry between two metals in close proximity to each other we began studying the reactivity of a dinuclear Cu(I) amidinate complex. The reaction of [(2,6-Me2C6H3N)2C(H)]2Cu2, 1, with I2 in tetrahydrofuran (THF), CH3CN, and toluene affords three new mixed-valence copper complexes [(2,6-Me2C6H3N)2C(H)]2Cu2(μ2-I3)(THF)2, 2, [(2,6-Me2C6H3N)2C(H)]2Cu2(μ2-I) (NCMe)2, 3, and [(2,6-Me2C6H3N)2C(H)]3Cu3(μ3-I)2, 4, respectively. The first two compounds were characterized by UV-vis and electron paramagnetic resonance spectroscopies, and their molecular structure was determined by X-ray crystallography. Both di- and trinuclear mixed-valence intermediates were characterized for the reaction of compound 1 to compound 4, and the molecular structure of 4 was determined by X-ray crystallography. The electronic structure of each of these complexes was also investigated using density functional theory.

  7. Data-Driven Contextual Valence Shifter Quantification for Multi-Theme Sentiment Analysis

    Science.gov (United States)

    Yu, Hongkun; Shang, Jingbo; Hsu, Meichun; Castellanos, Malú; Han, Jiawei

    2017-01-01

    Users often write reviews on different themes involving linguistic structures with complex sentiments. The sentiment polarity of a word can be different across themes. Moreover, contextual valence shifters may change sentiment polarity depending on the contexts that they appear in. Both challenges cannot be modeled effectively and explicitly in traditional sentiment analysis. Studying both phenomena requires multi-theme sentiment analysis at the word level, which is very interesting but significantly more challenging than overall polarity classification. To simultaneously resolve the multi-theme and sentiment shifting problems, we propose a data-driven framework to enable both capabilities: (1) polarity predictions of the same word in reviews of different themes, and (2) discovery and quantification of contextual valence shifters. The framework formulates multi-theme sentiment by factorizing the review sentiments with theme/word embeddings and then derives the shifter effect learning problem as a logistic regression. The improvement of sentiment polarity classification accuracy demonstrates not only the importance of multi-theme and sentiment shifting, but also effectiveness of our framework. Human evaluations and case studies further show the success of multi-theme word sentiment predictions and automatic effect quantification of contextual valence shifters. PMID:28232874

  8. Self-doping of molecular quantum-dot cellular automata: mixed valence zwitterions.

    Science.gov (United States)

    Lu, Yuhui; Lent, Craig

    2011-09-07

    Molecular quantum-dot cellular automata (QCA) is a promising paradigm for realizing molecular electronics. In molecular QCA, binary information is encoded in the distribution of intramolecular charge, and Coulomb interactions between neighboring molecules combine to create long-range correlations in charge distribution that can be exploited for signal transfer and computation. Appropriate mixed-valence species are promising candidates for single-molecule device operation. A complication arises because many mixed-valence compounds are ions and the associated counterions can potentially disrupt the correct flow of information through the circuit. We suggest a self-doping mechanism which incorporates the counterion covalently into the structure of a neutral molecular cell, thus producing a zwitterionic mixed-valence complex. The counterion is located at the geometrical center of the QCA molecule and bound to the working dots via covalent bonds, thus avoiding counterion effects that bias the system toward one binary information state or the other. We investigate the feasibility of using multiply charged anion (MCA) boron clusters, specifically closo-borate dianion, as building blocks. A first principle calculation shows that neutral, bistable, and switchable QCA molecules are possible. The self-doping mechanism is confirmed by molecular orbital analysis, which shows that MCA counterions can be stabilized by the electrostatic interaction between negatively charged counterions and positively charged working dots. This journal is © the Owner Societies 2011

  9. Neural mechanisms underlying valence inferences to sound: The role of the right angular gyrus.

    Science.gov (United States)

    Bravo, Fernando; Cross, Ian; Hawkins, Sarah; Gonzalez, Nadia; Docampo, Jorge; Bruno, Claudio; Stamatakis, Emmanuel Andreas

    2017-07-28

    We frequently infer others' intentions based on non-verbal auditory cues. Although the brain underpinnings of social cognition have been extensively studied, no empirical work has yet examined the impact of musical structure manipulation on the neural processing of emotional valence during mental state inferences. We used a novel sound-based theory-of-mind paradigm in which participants categorized stimuli of different sensory dissonance level in terms of positive/negative valence. Whilst consistent with previous studies which propose facilitated encoding of consonances, our results demonstrated that distinct levels of consonance/dissonance elicited differential influences on the right angular gyrus, an area implicated in mental state attribution and attention reorienting processes. Functional and effective connectivity analyses further showed that consonances modulated a specific inhibitory interaction from associative memory to mental state attribution substrates. Following evidence suggesting that individuals with autism may process social affective cues differently, we assessed the relationship between participants' task performance and self-reported autistic traits in clinically typical adults. Higher scores on the social cognition scales of the AQ were associated with deficits in recognising positive valence in consonant sound cues. These findings are discussed with respect to Bayesian perspectives on autistic perception, which highlight a functional failure to optimize precision in relation to prior beliefs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Cyberframing Cancer: An Exploratory Investigation of Valenced Cybercoping on Cancer Blogs.

    Science.gov (United States)

    Donovan, Erin E; Nelson, Erin C; Scheinfeld, Emily

    2017-01-01

    Although scholarship on coping with cancer implies many ways that coping is communicative, the discursive features of coping have been understudied. The purpose of the present investigation was to theorize the content of cancer blogs, a form of cybercoping, by examining valenced coping-relevant frames that bloggers use to describe their experiences with cancer. This research is both theoretically and methodologically innovative. Theoretically, we advance the concept of cyberframing by connecting the rather disconnected literatures on coping and framing and by studying this topic from a communication perspective. Methodologically, this is one of the few studies of coping with cancer that has used naturally occurring communication data to its advantage. A content analysis of cancer blog entries (N = 194) indicated that more than 90% of cancer blog posts were embedded in a valenced frame. The frames were either negative, positive, or balanced; balanced frames varied in the intensity of the valence. The most common frames were positive and balanced with low affect.

  11. Can culture influence body-specific associations between space and valence?

    Science.gov (United States)

    de la Fuente, Juanma; Casasanto, Daniel; Román, Antonio; Santiago, Julio

    2015-05-01

    People implicitly associate positive ideas with their dominant side of space and negative ideas with their non-dominant side. Right-handers tend to associate "good" with "right" and "bad" with "left," but left-handers associate "bad" with "right" and "good" with "left." Whereas right-handers' implicit associations align with idioms in language and culture that link "good" with "right," left-handers' implicit associations go against them. Can cultural conventions modulate the body-specific association between valence and left-right space? Here, we compared people from Spanish and Moroccan cultures, which differ in the strength of taboos against the use of the left hand, and therefore in their preference for the right. Results showed stronger explicit associations between space and valence in Moroccan participants than in Spaniards, but they did not show any increased tendency for right-handed Moroccans to associate "good" with "right" implicitly. Despite differences in cultural conventions between Spaniards and Moroccans, we find no evidence for a cross-cultural difference in the implicit association between space and valence, which appears to depend on patterns of bodily experience.

  12. Are Age Effects in Positivity Influenced by the Valence of Distractors?

    Science.gov (United States)

    Ziaei, Maryam; von Hippel, William; Henry, Julie D; Becker, Stefanie I

    2015-01-01

    An age-related 'positivity' effect has been identified, in which older adults show an information-processing bias towards positive emotional items in attention and memory. In the present study, we examined this positivity bias by using a novel paradigm in which emotional and neutral distractors were presented along with emotionally valenced targets. Thirty-five older and 37 younger adults were asked during encoding to attend to emotional targets paired with distractors that were either neutral or opposite in valence to the target. Pupillary responses were recorded during initial encoding as well as a later incidental recognition task. Memory and pupillary responses for negative items were not affected by the valence of distractors, suggesting that positive distractors did not automatically attract older adults' attention while they were encoding negative targets. Additionally, the pupil dilation to negative items mediated the relation between age and positivity in memory. Overall, memory and pupillary responses provide converging support for a cognitive control account of positivity effects in late adulthood and suggest a link between attentional processes and the memory positivity effect.

  13. Electrophysiological correlates of implicit valenced self-processing in high vs. low self-esteem individuals.

    Science.gov (United States)

    Grundy, John G; Benarroch, Miriam F F; Lebarr, A Nicole; Shedden, Judith M

    2015-01-01

    We provide the first high-temporal resolution account of the self-esteem implicit association test (IAT; Greenwald & Farnham, 2000) to highlight important similarities and differences between the cognitive processes corresponding to implicit valenced self-processing in high vs. low self-esteem individuals. We divided individuals into high and low self-esteem groups based on the Rosenberg self-esteem scale (Rosenberg, 1965) and administered the self-esteem IAT while recording electroencephalographic data. We show that the P2 captured group (high vs. low self-esteem) differences, the N250 and the late parietal positivity (LPP) captured differences corresponding to category pairing (self/positive vs. self/negative pairing), and the N1, P2, and P300-400 components captured interactions between self-esteem groups and whether the self was paired with positive or negative categories in the IAT. Overall, both high and low self-esteem groups were sensitive to the distinction between positive and negative information in relation to the self (me/negative generally displayed larger event-related potential amplitudes than me/positive), but for high self-esteem individuals, this difference was generally larger, earlier, and most pronounced over left-hemisphere electrodes. These electrophysiological differences may reflect differences in attentional resources devoted to teasing apart these two oppositely valenced associations. High self-esteem individuals appear to devote more automatic (early) attentional resources to strengthen the distinction between positively or negatively valenced information in relation to the self.

  14. A nucleus-dependent valence-space approach to nuclear structure

    CERN Document Server

    Stroberg, S R; Hergert, H; Holt, J D; Bogner, S K; Roth, R; Schwenk, A

    2016-01-01

    We present a nucleus-dependent valence-space approach for calculating ground and excited states of nuclei, which generalizes the shell-model in-medium similarity renormalization group to an ensemble reference with fractionally filled orbitals. Because the ensemble is used only as a reference, and not to represent physical states, no symmetry restoration is required. This allows us to capture 3N forces among valence nucleons with a valence-space Hamiltonian specifically targeted to each nucleus of interest. Predicted ground-state energies from carbon through nickel agree with results of other large-space ab initio methods, generally to the 1\\% level. In addition, we show that this new approach is required in order to obtain convergence for nuclei in the upper $p$ and $sd$ shells. Finally, we address the $1^+$/$3^+$ ground-state inversion problem in $^{22}\\text{Na}$ and $^{46}\\text{V}$. This approach extends the reach of ab initio nuclear structure calculations to essentially all light- and medium-mass nuclei.

  15. Valence-specific modulation in the accumulation of perceptual evidence prior to visual scene recognition.

    Directory of Open Access Journals (Sweden)

    Antonio Schettino

    Full Text Available Visual scene recognition is a dynamic process through which incoming sensory information is iteratively compared with predictions regarding the most likely identity of the input stimulus. In this study, we used a novel progressive unfolding task to characterize the accumulation of perceptual evidence prior to scene recognition, and its potential modulation by the emotional valence of these scenes. Our results show that emotional (pleasant and unpleasant scenes led to slower accumulation of evidence compared to neutral scenes. In addition, when controlling for the potential contribution of non-emotional factors (i.e., familiarity and complexity of the pictures, our results confirm a reliable shift in the accumulation of evidence for pleasant relative to neutral and unpleasant scenes, suggesting a valence-specific effect. These findings indicate that proactive iterations between sensory processing and top-down predictions during scene recognition are reliably influenced by the rapidly extracted (positive emotional valence of the visual stimuli. We interpret these findings in accordance with the notion of a genuine positivity offset during emotional scene recognition.

  16. Valence-Specific Modulation in the Accumulation of Perceptual Evidence Prior to Visual Scene Recognition

    Science.gov (United States)

    Schettino, Antonio; Loeys, Tom; Bossi, Manuela; Pourtois, Gilles

    2012-01-01

    Visual scene recognition is a dynamic process through which incoming sensory information is iteratively compared with predictions regarding the most likely identity of the input stimulus. In this study, we used a novel progressive unfolding task to characterize the accumulation of perceptual evidence prior to scene recognition, and its potential modulation by the emotional valence of these scenes. Our results show that emotional (pleasant and unpleasant) scenes led to slower accumulation of evidence compared to neutral scenes. In addition, when controlling for the potential contribution of non-emotional factors (i.e., familiarity and complexity of the pictures), our results confirm a reliable shift in the accumulation of evidence for pleasant relative to neutral and unpleasant scenes, suggesting a valence-specific effect. These findings indicate that proactive iterations between sensory processing and top-down predictions during scene recognition are reliably influenced by the rapidly extracted (positive) emotional valence of the visual stimuli. We interpret these findings in accordance with the notion of a genuine positivity offset during emotional scene recognition. PMID:22675437

  17. Valence-specific modulation in the accumulation of perceptual evidence prior to visual scene recognition.

    Science.gov (United States)

    Schettino, Antonio; Loeys, Tom; Bossi, Manuela; Pourtois, Gilles

    2012-01-01

    Visual scene recognition is a dynamic process through which incoming sensory information is iteratively compared with predictions regarding the most likely identity of the input stimulus. In this study, we used a novel progressive unfolding task to characterize the accumulation of perceptual evidence prior to scene recognition, and its potential modulation by the emotional valence of these scenes. Our results show that emotional (pleasant and unpleasant) scenes led to slower accumulation of evidence compared to neutral scenes. In addition, when controlling for the potential contribution of non-emotional factors (i.e., familiarity and complexity of the pictures), our results confirm a reliable shift in the accumulation of evidence for pleasant relative to neutral and unpleasant scenes, suggesting a valence-specific effect. These findings indicate that proactive iterations between sensory processing and top-down predictions during scene recognition are reliably influenced by the rapidly extracted (positive) emotional valence of the visual stimuli. We interpret these findings in accordance with the notion of a genuine positivity offset during emotional scene recognition.

  18. Accelerative and decelerative effects of hedonic valence and emotional arousal during visual scene processing.

    Science.gov (United States)

    Ihssen, Niklas; Keil, Andreas

    2013-01-01

    Perceptual processing of natural scene pictures is enhanced when the scene conveys emotional content. Such "motivated attention" to pleasant and unpleasant pictures has been shown to improve identification accuracy in non-speeded behavioural tasks. An open question is whether emotional content also modulates the speed of visual scene processing. In the present studies we show that unpleasant content reliably slowed two-choice categorization of pictures, irrespective of physical image properties, perceptual complexity, and categorization instructions. Conversely, pleasant content did not slow or even accelerated choice reactions, relative to neutral scenes. As indicated by lateralized readiness potentials, these effects occurred at cognitive processing rather than motor preparation/execution stages. Specifically, analysis of event-related potentials showed a prolongation of early scene discrimination for stimuli perceived as emotionally arousing, regardless of valence, and reflected in delayed peaks of the N1 component. In contrast, the timing of other processing steps, reflected in the P2 and late positive potential components and presumably related to post-discriminatory processes such as stimulus-response mapping, appeared to be determined by hedonic valence, with more pleasant scenes eliciting faster processing. Consistent with this model, varying arousal (low/high) within the emotional categories mediated the effects of valence on choice reaction speed. Functionally, arousal may prolong stimulus analysis in order to prevent erroneous and potentially harmful decisions. Pleasantness may act as a safety signal allowing rapid initiation of overt responses.

  19. Some properties of emission coordinates

    CERN Document Server

    Pozo, J M

    2006-01-01

    4 emitters broadcasting an increasing electromagnetic signal generate a system of relativistic coordinates for the space-time, called emission coordinates. Their physical realization requires an apparatus similar to the one of the Global Navigation Satellite Systems (GNSS). Several relativistic corrections are utilized for the current precisions, but the GNSS are conceived as classical (Newtonian) systems, which has deep implications in the way of operating them. The study of emission coordinates is an essential step in order to develop a fully relativistic theory of positioning systems. This talk presents some properties of emission coordinates. In particular, we characterize how any observer sees a configuration of satellites giving a degenerated system and show that the trajectories of the satellites select a unique privileged observer at each point and, for any observer, a set of 3 orthogonal spatial axes.

  20. Coordination Games on Dynamical Networks

    Directory of Open Access Journals (Sweden)

    Enea Pestelacci

    2010-07-01

    Full Text Available We propose a model in which agents of a population interacting according to a network of contacts play games of coordination with each other and can also dynamically break and redirect links to neighbors if they are unsatisfied. As a result, there is co-evolution of strategies in the population and of the graph that represents the network of contacts. We apply the model to the class of pure and general coordination games. For pure coordination games, the networks co-evolve towards the polarization of different strategies. In the case of general coordination games our results show that the possibility of refusing neighbors and choosing different partners increases the success rate of the Pareto-dominant equilibrium.

  1. Fedosov supermanifolds: II. Normal coordinates

    CERN Document Server

    Geyer, B; Geyer, Bodo; Lavrov, Peter

    2004-01-01

    The study of recently introduced Fedosov supermanifolds is continued. Using normal coordinates, properties of even and odd symplectic supermanifolds endowed with a symmetric connection respecting given sympletic structure are studied.

  2. Surface normals and barycentric coordinates

    Directory of Open Access Journals (Sweden)

    Mullineux Glen

    1996-01-01

    Full Text Available The normal to a triangular parametric surface is investigated where the parameters used are barycentric coordinates. Formulae for the normal are obtained for non-rational and rational surfaces.

  3. Ellipsoidal analysis of coordination polyhedra

    Science.gov (United States)

    Cumby, James; Attfield, J. Paul

    2017-02-01

    The idea of the coordination polyhedron is essential to understanding chemical structure. Simple polyhedra in crystalline compounds are often deformed due to structural complexity or electronic instabilities so distortion analysis methods are useful. Here we demonstrate that analysis of the minimum bounding ellipsoid of a coordination polyhedron provides a general method for studying distortion, yielding parameters that are sensitive to various orders in metal oxide examples. Ellipsoidal analysis leads to discovery of a general switching of polyhedral distortions at symmetry-disallowed transitions in perovskites that may evidence underlying coordination bistability, and reveals a weak off-centre `d5 effect' for Fe3+ ions that could be exploited in multiferroics. Separating electronic distortions from intrinsic deformations within the low temperature superstructure of magnetite provides new insights into the charge and trimeron orders. Ellipsoidal analysis can be useful for exploring local structure in many materials such as coordination complexes and frameworks, organometallics and organic molecules.

  4. Kaluza's theory in generalized coordinates

    CERN Document Server

    García-Perciante, A L; García-Colin, L S; Garcia-Perciante, Ana Laura; Sandoval-Villalbazo, Alfredo

    2001-01-01

    Maxwell's equations can be obtained in generalized coordinates by considering the electromagnetic field as an external agent. The work here presented shows how to obtain the electrodynamics for a charged particle in generalized coordinates eliminating the concept of external force. Based on Kaluza's formalism, the one here presented extends the 5x5 metric into a 6x6 space-time giving enough room to include magnetic monopoles in a very natural way.

  5. Coordination theory and collaboration technology

    CERN Document Server

    Olson, Gary M; Smith, John B

    2001-01-01

    The National Science Foundation funded the first Coordination Theory and Collaboration Technology initiative to look at systems that support collaborations in business and elsewhere. This book explores the global revolution in human interconnectedness. It will discuss the various collaborative workgroups and their use in technology. The initiative focuses on processes of coordination and cooperation among autonomous units in human systems, in computer and communication systems, and in hybrid organizations of both systems. This initiative is motivated by three scientific issues which have been

  6. CPN Models in General Coordinates

    CERN Document Server

    Barnes, K J

    2002-01-01

    An analysis of CPN models is given in terms of general coordinates or arbitrary interpolating fields.Only closed expressions made from simple functions are involved.Special attention is given to CP2 and CP4. In the first of these the retrieval of stereographic coordinates reveals the hermitian form of the metric. A similar analysis for the latter case allows comparison with the Fubini-Study metric.

  7. Inflation, Growth and Policy Coordination

    OpenAIRE

    Renato E. Reside Jr.; Parantap Basu

    1996-01-01

    The effect of monetary policy on output growth and inflation is examined in a monetary endogenous growth model with an explicit banking sector that intermediates capital. Monetary policy is coordinated with fiscal policy in the sense that all the seigniorage revenue gleaned through the inflation tax is spent to make efficient provision of public services. With the reserve requirement and money growth as instruments, policy coordination implies that one instrument may be solved endogenously wh...

  8. P-T PHASE DIAGRAM AND GOLD VALENCE STATE OF NEW GOLD MIXED-VALENCE COMPLEXES, Cs2[AuIX2][AuIIIY4](X, Y = Cl, Br, I; X ¹ Y

    Directory of Open Access Journals (Sweden)

    K. Ikeda

    2004-12-01

    Full Text Available Cs2[AuIX2][AuIIIX4](X = Cl, Br, and I is well known for the perovskite-type gold mixed-valence system. This system undergoes pressure-induced and photo-induced Au valence transition from the mixed valence state of AuI,III to the single valence state of AuII. Recently, we have succeeded in synthesizing new gold mixed-valence complexes having perovskite-type structure, Cs2[AuIX2][AuIIIY4](X, Y = halogen, X ¹ Y, in organic solvent by using a new method. This hetero-halogen bridged gold mixed-valence system was confirmed by means of Raman spectroscopy. From the analysis of 197Au Mössbauer spectra, it was elucidated that the charge transfer interaction between AuI(5dx2-y2 and AuIII(5dx2-y2in the a-b plane becomes dominant for the AuI-AuIII interaction in Cs2[AuIX2][AuIIIY4] (X, Y = Cl, Br, and I in the order of X = Cl < Br < I, where Y is fixed. In order to elucidate the Au valence transition for Cs2[AuIX2][AuIIIY4], we have investigated the X-ray diffraction and Raman spectra under high pressure. Moreover, we have synthesized TlAuX3(X = Cl and Br having cubic perovskite structure and highly conducting behavior. The Au valence state in TlAuX3 is considered to be AuII at ambient pressure.

  9. Managing interteam coordination within and between organizations

    NARCIS (Netherlands)

    de Vries, Thomas Arend

    2015-01-01

    To accomplish complex tasks and effectively respond to environmental contingencies, teams must coordinate task-related issues with other teams (i.e., interteam coordination). Regrettably, interteam coordination is often complicated by misunderstandings that can arise from differences in teams’

  10. Valence of Ti, V, and Cr in Apollo 14 aluminous basalts 14053 and 14072

    Science.gov (United States)

    Simon, Steven B.; Sutton, Stephen R.

    2017-09-01

    The valences of Ti, V, and Cr in olivine and pyroxene, important indicators of the fO2 of the source region of their host rocks, can be readily measured nondestructively by XANES (X-ray absorption near edge structure) spectroscopy, but little such work has been done on lunar rocks, and there is some uncertainty regarding the presence of Ti3+ in lunar silicates and the redox state of the lunar mantle. This is the first study involving direct XANES measurement of valences of multivalent cations in lunar rocks. Because high alumina activity facilitates substitution of Ti cations into octahedral rather than tetrahedral sites in pyroxene and Ti3+ only enters octahedral sites, two aluminous basalts from Apollo 14, 14053 and 14072, were studied. Most pyroxene contains little or no detectable Ti3+, but in both samples relatively early, magnesian pyroxene was found that has Ti valences that are not within error of 4; in 14053, this component has an average Ti valence of 3.81 ± 0.06 (i.e., Ti3+/[Ti3+ + Ti4+ = 0.19]). This pyroxene has relatively low atomic Ti/Al ratios ( 0.5 contains Ti3+ and pyroxene with lower ratios does not. Later pyroxene, with lower Mg/Fe and higher Ti/Al ratios, has higher proportions of Ti (all Ti4+) in tetrahedral sites. All pyroxene analyzed contains divalent Cr, ranging from 15 to 30% of the Cr present, and all but one analysis spot contains divalent V, accounting for 0 to 40% (typically 20-30%) of the V present. Three analyses of olivine in 14053 do not show any Ti3+, but Ti valences in 14072 olivine range from 4 down to 3.70 ± 0.10. In 14053 olivine, 50% of the Cr and 60% of the V are divalent. In 14072 olivine, the divalent percentages are 20% for Cr and 20-60% for V. These results indicate significant proportions of divalent Cr and V and limited amounts of trivalent Ti in the parental melts, especially when crystal/liquid partitioning preferences are taken into account. These features are consistent with an fO2 closer to IW - 2 than to IW

  11. Valence XPS structure and chemical bond in Cs2UO2Cl4

    Directory of Open Access Journals (Sweden)

    Teterin Yury A.

    2016-01-01

    Full Text Available Quantitative analysis was done of the valence electrons X-ray photoelectron spectra structure in the binding energy (BE range of 0 eV to ~35 eV for crystalline dicaesium tetrachloro-dioxouranium (VI (Cs2UO2Cl4. This compound contains the uranyl group UO2. The BE and structure of the core electronic shells (~35 eV-1250 eV, as well as the relativistic discrete variation calculation results for the UO2Cl4(D4h cluster reflecting U close environment in Cs2UO2Cl4 were taken into account. The experimental data show that many-body effects due to the presence of cesium and chlorine contribute to the outer valence (0-~15 eV BE spectral structure much less than to the inner valence (~15 eV-~35 eV BE one. The filled U5f electronic states were theoretically calculated and experimentally confirmed to be present in the valence band of Cs2UO2Cl4. It corroborates the suggestion on the direct participation of the U5f electrons in the chemical bond. Electrons of the U6p atomic orbitals participate in formation of both the inner (IVMO and the outer (OVMO valence molecular orbitals (bands. The filled U6p and the O2s, Cl3s electronic shells were found to make the largest contributions to the IVMO formation. The molecular orbitals composition and the sequence order in the binding energy range 0 eV-~35 eV in the UO2Cl4 cluster were established. The experimental and theoretical data allowed a quantitative molecular orbitals scheme for the UO2Cl4 cluster in the BE range 0-~35 eV, which is fundamental for both understanding the chemical bond nature in Cs2UO2Cl4 and the interpretation of other X-ray spectra of Cs2UO2Cl4. The contributions to the chemical binding for the UO2Cl4 cluster were evaluated to be: the OVMO contribution - 76%, and the IVMO contribution - 24 %.

  12. Contextual blending of ingroup/outgroup face stimuli and word valence: LPP modulation and convergence of measures

    Directory of Open Access Journals (Sweden)

    González Ramiro

    2009-06-01

    Full Text Available Abstract Background Several event related potential (ERP studies have investigated the time course of different aspects of evaluative processing in social bias research. Various reports suggest that the late positive potential (LPP is modulated by basic evaluative processes, and some reports suggest that in-/outgroup relative position affects ERP responses. In order to study possible LPP blending between facial race processing and semantic valence (positive or negative words, we recorded ERPs while indigenous and non-indigenous participants who were matched by age and gender performed an implicit association test (IAT. The task involved categorizing faces (ingroup and outgroup and words (positive and negative. Since our paradigm implies an evaluative task with positive and negative valence association, a frontal distribution of LPPs similar to that found in previous reports was expected. At the same time, we predicted that LPP valence lateralization would be modulated not only by positive/negative associations but also by particular combinations of valence, face stimuli and participant relative position. Results Results showed that, during an IAT, indigenous participants with greater behavioral ingroup bias displayed a frontal LPP that was modulated in terms of complex contextual associations involving ethnic group and valence. The LPP was lateralized to the right for negative valence stimuli and to the left for positive valence stimuli. This valence lateralization was influenced by the combination of valence and membership type relevant to compatibility with prejudice toward a minority. Behavioral data from the IAT and an explicit attitudes questionnaire were used to clarify this finding and showed that ingroup bias plays an important role. Both ingroup favoritism and indigenous/non-indigenous differences were consistently present in the data. Conclusion Our results suggest that frontal LPP is elicited by contextual blending of evaluative

  13. Conforming to coordinate: children use majority information for peer coordination.

    Science.gov (United States)

    Grueneisen, Sebastian; Wyman, Emily; Tomasello, Michael

    2015-03-01

    Humans are constantly required to coordinate their behaviour with others. As this often relies on everyone's convergence on the same strategy (e.g., driving on the left side of the road), a common solution is to conform to majority behaviour. In this study, we presented 5-year-old children with a coordination problem: To retrieve some rewards, they had to choose the same of four options as a peer partner--in reality a stooge--whose decision they were unable to see. Before making a choice, they watched a video showing how other children from their partner's peer group had behaved; a majority chose the same option and a minority chose a different one. In a control condition, children watched the same video but could then retrieve the reward irrespective of their partner's choice (i.e., no coordination was necessary). Children followed the majority more often when coordination was required. Moreover, conformers mostly justified their choices by referring to the majority from the video demonstration. This study is the first to show that young children are able to strategically coordinate decisions with peers by conforming to the majority.

  14. Metallogels from Coordination Complexes, Organometallic, and Coordination Polymers.

    Science.gov (United States)

    Dastidar, Parthasarathi; Ganguly, Sumi; Sarkar, Koushik

    2016-09-20

    A supramolecular gel results from the immobilization of solvent molecules on a 3D network of gelator molecules stabilized by various supramolecular interactions that include hydrogen bonding, π-π stacking, van der Waals interactions, and halogen bonding. In a metallogel, a metal is a part of the gel network as a coordinated metal ion (in a discrete coordination complex), as a cross-linking metal node with a multitopic ligand (in coordination polymer), and as metal nanoparticles adhered to the gel network. Although the field is relatively new, research into metallogels has experienced a considerable upsurge owing to its fundamental importance in supramolecular chemistry and various potential applications. This focus review aims to provide an insight into the development of designing metallogelators. Because of the limited scope, discussions are confined to examples pertaining to metallogelators derived from discrete coordination complexes, organometallic gelators, and coordination polymers. This review is expected to enlighten readers on the current development of designing metallogelators of the abovementioned class of molecules. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Werner coordination chemistry and neurodegeneration.

    Science.gov (United States)

    Telpoukhovskaia, Maria A; Orvig, Chris

    2013-02-21

    Neurodegenerative diseases are capturing the world's attention as being the next set of diseases we must tackle collectively. Not only are the patients experiencing gradual cognitive and physical decline in most cases, but these diseases are fatal with no prevention currently available. As these diseases are progressive, providing care and symptom treatment for the ageing population is becoming both a medical and a financial challenge. This review discusses how Werner coordination chemistry plays a role in three diseases - those of Alzheimer's, Parkinson's, and prions. Metal ions are considered to be involved in these diseases in part via their propensity to cause toxic aggregation of proteins. First, the coordination of metal ions, with emphasis on copper(II), to metalloproteins that are hallmarks of these diseases - amyloid β, α-synuclein, and prion, respectively - will be discussed. We will present the current understanding of the metal coordination environments created by the amino acids of these proteins, as well as metal binding affinity. Second, a diverse set of examples of rationally designed metal chelators to outcompete this deleterious binding will be examined based on coordination mode and affinity toward bio-relevant metal ions. Overall, this review will give a general overview of protein and metal chelator coordination environments in neurodegenerative diseases.

  16. New route to the mixed valence semiquinone-catecholate based mononuclear FeIII and catecholate based dinuclear MnIII complexes: first experimental evidence of valence tautomerism in an iron complex.

    Science.gov (United States)

    Shaikh, Nizamuddin; Goswami, Sanchita; Panja, Anangamohan; Wang, Xin-Yi; Gao, Song; Butcher, Ray J; Banerjee, Pradyot

    2004-09-20

    The semiquinone-catecholate based mixed valence complex, [FeIII(bispicen)(Cl4Cat)(Cl4SQ)] x DMF (1), and catecholate based (H2bispictn)[Mn2III(Cl4Cat)4(DMF)2] (2) (bispicen = N,N'-bis(2-pyridylmethyl)-1,2-ethanediamine, bispictn = N,N'-bis(2-pyridylmethyl)-1,3-propanediamine, Cl4Cat = tetrachlorocatecholate dianion, and Cl4SQ = tetrachlorosemiquinone radical anion) were synthesized directly utilizing a facile route. Both the complexes have been characterized by single crystal X-ray diffraction study. The electronic structures have been elucidated by UV-vis-NIR absorption spectroscopy, cyclic voltammetry, EPR, and magnetic properties. The structural as well as spectroscopic features support the mixed valence tetrachlorosemiquinone-tetrachlorocatecholate charge distribution in 1. The ligand based mixed valence state was further confirmed by the presence of an intervalence charge transfer (IVCT) band in the 1900 nm region both in solution and in the solid. The intramolecular electron transfer, a phenomenon known as valence tautomerism (VT), has been followed by electronic absorption spectroscopy. For 1, the isomeric form [FeIII(bispicen)(Cl4Cat)(Cl4SQ)] is favored at low temperature, while at an elevated temperature, the [FeII(bispicen)(Cl4SQ)2] redox isomer dominates. Infrared as well as UV-vis-NIR spectral characterization for 2 suggest that the MnIII(Cat)2- moiety is admixed with its mixed valence semiquinone-catecholate isomer MnII(SQ)(Cat)-, and the electronic absorption spectrum is dominated by the mixed charged species. The origin of the intervalence charge transfer band in the 1900 nm range is associated with the mixed valence form, MnII(Cl4Cat)(Cl4SQ)-. The observation of VT in complex 1 is the first example where a mixed valence semiquinone-catecholate iron(III) complex undergoes intramolecular electron transfer similar to manganese and cobalt complexes.

  17. COCO: Conversion of Celestial Coordinates

    Science.gov (United States)

    Wallace, Patrick

    2014-06-01

    The COCO program converts star coordinates from one system to another. Both the improved IAU system, post-1976, and the old pre-1976 system are supported. COCO can perform accurate transformations between multiple coordinate systems. COCO's user-interface is spartan but efficient and the program offers control over report resolution. All input is free-format, and defaults are provided where this is meaningful. COCO uses SLALIB (ascl:1403.025) and is distributed as part of the Starlink software collection (ascl:1110.012).

  18. A coordination language for databases

    DEFF Research Database (Denmark)

    Li, Ximeng; Wu, Xi; Lluch Lafuente, Alberto

    2017-01-01

    We present a coordination language for the modeling of distributed database applications. The language, baptized Klaim-DB, borrows the concepts of localities and nets of the coordination language Klaim but re-incarnates the tuple spaces of Klaim as databases. It provides high-level abstractions...... in the semantics. The use of the language is illustrated in a scenario where the sales from different branches of a chain of department stores are aggregated from their local databases. Raising the abstraction level and encapsulating integrity checks in the language primitives have benefited the modeling task...

  19. Contextual Valence and Sociality Jointly Influence the Early and Later Stages of Neutral Face Processing

    Directory of Open Access Journals (Sweden)

    Mengsi Xu

    2016-08-01

    Full Text Available Recent studies have demonstrated that face perception is influenced by emotional contextual information. However, because facial expressions are routinely decoded and understood during social communication, sociality should also be considered—that is, it seems necessary to explore whether emotional contextual effects are influenced by the sociality of contextual information. Furthermore, although one behavioural study has explored the effects of context on selective attention to faces, the exact underlying mechanisms remain unknown. Therefore, the current study investigated how valence and sociality of contextual information influenced the early and later stages of neutral face processing. We first employed an established affective learning procedure, wherein neutral faces were paired with verbal information that differed in valence (negative, neutral and sociality (social, non-social, to manipulate contextual information. Then, to explore the effects of context on face perception, participants performed a face perception task, while the N170, early posterior negativity (EPN, and late positive potential (LPP components were measured. Finally, to explore the effects of context on selective attention, participants performed a dot probe task while the N2pc was recorded. The results showed that, in the face perception task, faces paired with negative social information elicited greater EPN and LPP than did faces paired with neutral social information; no differences existed between faces paired with negative and neutral non-social information. In the dot probe task, faces paired with negative social information elicited a more negative N2pc amplitude (indicating attentional bias than did faces paired with neutral social information; the N2pc did not differ between faces paired with negative and neutral non-social information. Together, these results suggest that contextual information influenced both face perception and selective attention, and

  20. Contextual Valence and Sociality Jointly Influence the Early and Later Stages of Neutral Face Processing.

    Science.gov (United States)

    Xu, Mengsi; Li, Zhiai; Diao, Liuting; Fan, Lingxia; Yang, Dong

    2016-01-01

    Recent studies have demonstrated that face perception is influenced by emotional contextual information. However, because facial expressions are routinely decoded and understood during social communication, sociality should also be considered-that is, it seems necessary to explore whether emotional contextual effects are influenced by the sociality of contextual information. Furthermore, although one behavioral study has explored the effects of context on selective attention to faces, the exact underlying mechanisms remain unknown. Therefore, the current study investigated how valence and sociality of contextual information influenced the early and later stages of neutral face processing. We first employed an established affective learning procedure, wherein neutral faces were paired with verbal information that differed in valence (negative, neutral) and sociality (social, non-social), to manipulate contextual information. Then, to explore the effects of context on face perception, participants performed a face perception task, while the N170, early posterior negativity (EPN), and late positive potential (LPP) components were measured. Finally, to explore the effects of context on selective attention, participants performed a dot probe task while the N2pc was recorded. The results showed that, in the face perception task, faces paired with negative social information elicited greater EPN and LPP than did faces paired with neutral social information; no differences existed between faces paired with negative and neutral non-social information. In the dot probe task, faces paired with negative social information elicited a more negative N2pc amplitude (indicating attentional bias) than did faces paired with neutral social information; the N2pc did not differ between faces paired with negative and neutral non-social information. Together, these results suggest that contextual information influenced both face perception and selective attention, and these context

  1. Valence Topological Charge-Transfer Indices for Reflecting Polarity: Correction for Heteromolecules

    Directory of Open Access Journals (Sweden)

    F. Torrens

    2005-02-01

    Full Text Available Valence topological charge-transfer (CT indices are applied to the calculationof dipole moments μ. The μ calculated by algebraic and vector semisums of the CTindices are defined. The model is generalized for molecules with heteroatoms andcorrected for sp3-heteromolecules. The ability of the indices for the description of themolecular charge distribution is established by comparing them with μ of the valence-isoelectronic series of cyclopentadiene, benzene and styrene. Two CT indices, μvec(vector semisum of vertex-pair μ and μvecV (valence μvec are proposed. The μvecVbehaviour is intermediate between μvec and μexperiment. The correction is produced in thecorrect direction. The best results are obtained for the greatest group. Inclusion of theheteroatom in the π-electron system is beneficial for the description of μ, owing to eitherthe role of additional p and/or d orbitals provided by the heteroatom or the role of stericfactors in the π-electron conjugation. The steric effect is almost constant along the seriesand the dominating effect is electronic. Inclusion of the heteroatom enhances μ, whichcan improve the solubility of the molecule. For heteroatoms in the same group, the ringsize and the degree of ring flattering are inversely proportional to their electronegativity.

  2. Mineralogical Changes and Fe Valence State During Antigorite Breakdown in Subduction Settings

    Science.gov (United States)

    Merkulova, M.; Munoz, M.; Vidal, O.; Brunet, F.

    2014-12-01

    Mineralogical and petrological changes in subduction zones include transition from altered hydrated rocks (mostly serpentinites) to anhydrous peridotites with the release of fluid. Changes in the valence of iron and other ions capable for electron-exchanges remain poorly constrained during this transition. The approach of this work comprises thermodynamic modeling and experiments based on the use of a piston-cylinder apparatus. We show a series of experiments with the range of temperatures from 550 to 850oC at pressure of 2 GPa, which perform the antigorite dehydration reaction using Fe-bearing antigorite and magnetite as starting material. The experimentally produced mineral phases have been characterized by X-ray diffraction, electron microprobe and X-ray absorption spectroscopy (XANES at the iron K-edge). At each step of serpentinite dehydration reaction we provide the modal abundance of minerals, the amount of releasing water, the chemical compositions of phases and the Fe-oxidation state. The modal abundance of experimental product assemblage changes gradually. Thus, antigorite dominates untill 650 oC and it fully dehydrates after 700 oC. Olivine and enstatite are the most prevailing phases at higher temperatures. However, chlorite, diopside and tremolite are observed during the reaction. Furthermore, olivine and antigorite have been found to change their iron content depending on temperature, which is in consistent with thermodynamic modeling accomplished in the present study. As the reaction progress with the increase of temperature, evolution of iron oxidation state changes. Antigorite containing mostly Fe3+ releases water and breaks down into olivine and enstatite containing Fe2+. The bulk Fe3+/Fetotal ratio decreases rapidly during first steps of the reaction and continue decreasing after antigorite disappearance. In our results we have showed the analyses of Fe valence state in both bulk rocks and separate minerals. Characterizing the evolution of

  3. Valence band energy spectrum of HgTe quantum wells with an inverted band structure

    Science.gov (United States)

    Minkov, G. M.; Aleshkin, V. Ya.; Rut, O. E.; Sherstobitov, A. A.; Germanenko, A. V.; Dvoretski, S. A.; Mikhailov, N. N.

    2017-07-01

    The energy spectrum of the valence band in HgTe /CdxHg1 -xTe quantum wells of a width (8 -20 ) nm has been studied experimentally by magnetotransport effects and theoretically in the framework of a four-band k P method. Comparison of the Hall density with the density found from a period of the Shubnikov-de Haas (SdH) oscillations clearly shows that the degeneracy of states of the top of the valence band is equal to 2 at the hole density p top of the valence band consists of four spin-degenerate extremes located at k ≠0 (valleys) which gives the total degeneracy K =8 . It is shown that taking into account the "mixing of states" at the interfaces leads to the removal of the spin degeneracy that reduces the degeneracy to K =4 . Accounting for any additional asymmetry, for example, due to the difference in the mixing parameters at the interfaces, the different broadening of the boundaries of the well, etc., leads to reduction of the valleys degeneracy, making K =2 . It is noteworthy that for our case twofold degeneracy occurs due to degeneracy of two single-spin valleys. The hole effective mass (mh) determined from analysis of the temperature dependence of the amplitude of the SdH oscillations shows that mh is equal to (0.25 ±0.02 ) m0 and weakly increases with the hole density. Such a value of mh and its dependence on the hole density are in a good agreement with the calculated effective mass.

  4. [Repeated measurement of memory with valenced test items: verbal memory, working memory and autobiographic memory].

    Science.gov (United States)

    Kuffel, A; Terfehr, K; Uhlmann, C; Schreiner, J; Löwe, B; Spitzer, C; Wingenfeld, K

    2013-07-01

    A large number of questions in clinical and/or experimental neuropsychology require the multiple repetition of memory tests at relatively short intervals. Studies on the impact of the associated exercise and interference effects on the validity of the test results are rare. Moreover, hardly any neuropsychological instruments exist to date to record the memory performance with several parallel versions in which the emotional valence of the test material is also taken into consideration. The aim of the present study was to test whether a working memory test (WST, a digit-span task with neutral or negative distraction stimuli) devised by our workgroup can be used with repeated measurements. This question was also examined in parallel versions of a wordlist learning paradigm and an autobiographical memory test (AMT). Both tests contained stimuli with neutral, positive and negative valence. Twenty-four participants completed the memory testing including the working memory test and three versions of a wordlist and the AMT at intervals of a week apiece (measuring points 1. - 3.). The results reveal consistent performances across the three measuring points in the working and autobiographical memory test. The valence of the stimulus material did not influence the memory performance. In the delayed recall of the wordlist an improvement in memory performance over time was seen. The tests on working memory presented and the parallel versions for the declarative and autobiographical memory constitute informal economic instruments within the scope of the measurement repeatability designs. While the WST and AMT are appropriate for study designs with repeated measurements at relatively short intervals, longer intervals might seem more favourable for the use of wordlist learning paradigms. © Georg Thieme Verlag KG Stuttgart · New York.

  5. The effects of valence-based and discrete emotional states on aesthetic response.

    Science.gov (United States)

    Cheng, Yin-Hui

    2013-01-01

    There is increasing recognition that consumer aesthetics--the responses of consumers to the aesthetic or appearance aspects of products--has become an important area of marketing in recent years. Consumer aesthetic responses to a product are a source of pleasure for the consumer. Previous research into the aesthetic responses to products has often emphasized exterior factors and visual design, but studies have seldom considered the psychological aesthetic experience of consumers, and in particular their emotional state. This study attempts to bridge this gap by examining the link between consumers' emotions and their aesthetic response to a product. Thus, the major goal of this study was to determine how valence-based and discrete emotional states influence choice. In Studies 1 and 2, positive and negative emotions were manipulated to implement two different induction techniques and explore the effect of emotions on participants' choices in two separate experiments. The results of both experiments confirmed the predictions, indicating that aesthetic responses and purchase intention are functions of emotional valence, such that both are stronger for people in a positive emotional state than for those in a negative emotional state. Study 2 also used a neutral affective state to establish the robustness of this observed effect of incidental affect. The results of Study 3 demonstrate that aesthetic response and purchase intention are not only a function of affect valence, but also are affected by the certainty appraisal associated with specific affective states. This research, therefore, contributes to the literature by offering empirical evidence that incidental affect is a determinant of aesthetic response.

  6. Age-related alterations in simple declarative memory and the effect of negative stimulus valence.

    Science.gov (United States)

    Murty, Vishnu P; Sambataro, Fabio; Das, Saumitra; Tan, Hao-Yang; Callicott, Joseph H; Goldberg, Terry E; Meyer-Lindenberg, Andreas; Weinberger, Daniel R; Mattay, Venkata S

    2009-10-01

    Healthy aging has been shown to modulate the neural circuitry underlying simple declarative memory; however, the functional impact of negative stimulus valence on these changes has not been fully investigated. Using BOLD fMRI, we explored the effects of aging on behavioral performance, neural activity, and functional coupling during the encoding and retrieval of novel aversive and neutral scenes. Behaviorally, there was a main effect of valence with better recognition performance for aversive greater than neutral stimuli in both age groups. There was also a main effect of age with better recognition performance in younger participants compared to older participants. At the imaging level, there was a main effect of valence with increased activity in the medial-temporal lobe (amygdala and hippocampus) during both encoding and retrieval of aversive relative to neutral stimuli. There was also a main effect of age with older participants showing decreased engagement of medial-temporal lobe structures and increased engagement of prefrontal structures during both encoding and retrieval sessions. Interestingly, older participants presented with relatively decreased amygdalar-hippocampal coupling and increased amygdalar-prefrontal coupling when compared to younger participants. Furthermore, older participants showed increased activation in prefrontal cortices and decreased activation in the amygdala when contrasting the retrieval of aversive and neutral scenes. These results suggest that although normal aging is associated with a decline in declarative memory with alterations in the neural activity and connectivity of brain regions underlying simple declarative memory, memory for aversive stimuli is relatively better preserved than for neutral stimuli, possibly through greater compensatory prefrontal cortical activity.

  7. 7 CFR 22.201 - Coordination.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Coordination. 22.201 Section 22.201 Agriculture Office of the Secretary of Agriculture RURAL DEVELOPMENT COORDINATION Roles and Responsibilities of Federal Government § 22.201 Coordination. The following identifies types and levels of coordination: (a) Washington...

  8. 15 CFR 923.56 - Plan coordination.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Plan coordination. 923.56 Section 923... COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Coordination, Public Involvement and National Interest § 923.56 Plan coordination. (a) The management program must be coordinated with local, areawide,...

  9. 40 CFR 109.6 - Coordination.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Coordination. 109.6 Section 109.6..., LOCAL AND REGIONAL OIL REMOVAL CONTINGENCY PLANS § 109.6 Coordination. For the purposes of coordination... coordination of these contingency plans with the National Oil and Hazardous Materials Pollution...

  10. 29 CFR 42.8 - Coordination plan.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Coordination plan. 42.8 Section 42.8 Labor Office of the Secretary of Labor COORDINATED ENFORCEMENT § 42.8 Coordination plan. (a) Based upon, among other things, the... coordination plan concerning farm labor-related responsibilities of the Department, including migrant housing...

  11. 33 CFR 165.8 - Geographic coordinates.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Geographic coordinates. 165.8... Geographic coordinates. Geographic coordinates expressed in terms of latitude or longitude, or both, are not... 1983 (NAD 83), unless such geographic coordinates are expressly labeled NAD 83. Geographic...

  12. The Convex Coordinates of the Symmedian Point

    Science.gov (United States)

    Boyd, J. N.; Raychowdhury, P. N.

    2006-01-01

    In this note, we recall the convex (or barycentric) coordinates of the points of a closed triangular region. We relate the convex and trilinear coordinates of the interior points of the triangular region. We use the relationship between convex and trilinear coordinates to calculate the convex coordinates of the symmedian point of the triangular…

  13. 78 FR 73819 - Forest Resource Coordinating Committee

    Science.gov (United States)

    2013-12-09

    ... Forest Service Forest Resource Coordinating Committee AGENCY: Forest Service, USDA. ACTION: Notice of...-18, 2013 meeting of the Forest Resource Coordinating Committee due to the Government partial shutdown... INFORMATION CONTACT: Maya Solomon, Forest Resource Coordinating Committee Program Coordinator; by phone at...

  14. Alternative structure of TiO2 with higher energy valence band edge

    Science.gov (United States)

    Coh, Sinisa; Yu, Peter Y.; Aoki, Yuta; Saito, Susumu; Louie, Steven G.; Cohen, Marvin L.

    2017-02-01

    We propose an alternative structure of TiO2 anatase that has a higher energy oxygen p -like valence band maximum than pristine TiO2 anatase and thus has a much better alignment with the water splitting levels. This alternative structure is unique when considering a large subspace of possible structural distortions of TiO2 anatase. We propose two routes towards this state and argue that one of them might have been realized in the recently discovered so-called black TiO2.

  15. Pressure-Resistant Intermediate Valence in the Kondo Insulator SmB_{6}.

    Science.gov (United States)

    Butch, Nicholas P; Paglione, Johnpierre; Chow, Paul; Xiao, Yuming; Marianetti, Chris A; Booth, Corwin H; Jeffries, Jason R

    2016-04-15

    Resonant x-ray emission spectroscopy was used to determine the pressure dependence of the f-electron occupancy in the Kondo insulator SmB_{6}. Applied pressure reduces the f occupancy, but surprisingly, the material maintains a significant divalent character up to a pressure of at least 35 GPa. Thus, the closure of the resistive activation energy gap and onset of magnetic order are not driven by stabilization of an integer valent state. Over the entire pressure range, the material maintains a remarkably stable intermediate valence that can in principle support a nontrivial band structure.

  16. Valence electron structure analysis of refining mecha-nism of Sc and Ti additions on aluminum

    Institute of Scientific and Technical Information of China (English)

    LI PieJie; YE YiCong; HE LiangJu

    2009-01-01

    The mechanism of the difference of refining effect between Sc and Ti adding to aluminum can not be explained substantially with traditional theory. Valence electron structures of AI-Ti and Al-Sc alloys have been studied by using the empirical electron theory of solids and molecules (EET). The covalent bond electron numbers and interfacial electron density differences are calculated. The conclusion is that, in the two alloys, different covalent bond electron numbers of nucleation particles, and different electron densities on the interface between the second phase particles and the matrix, fundamentally lead to the difference of refining effect between Sc and Ti adding to aluminum.

  17. Spontaneous polarization of the neutral interface for valence asymmetric coulombic systems.

    Science.gov (United States)

    di Caprio, D; Holovko, M

    2009-02-19

    In this paper, we discuss the phenomenon of a spontaneous polarization of a neutral hard planar interface for valence asymmetric Coulombic systems. Within a field theoretical description, we account for the existence of nontrivial charge density and electric potential profiles. The analysis of the phenomenon shows that the effect is related to combinatorics in relation with the existence of the two independent species cations and anions. This simple and basic feature is related to the quantum mechanical properties of the system. The theoretical results are compared with numerical simulations data and are shown to be in very good agreement, which a fortiori justifies our physical interpretation.

  18. Simultaneous occurrence of three different valence tautomers in meso-vinylruthenium-modified zinc porphyrin radical cations.

    Science.gov (United States)

    Chen, Jing; Wuttke, Evelyn; Polit, Walther; Exner, Thomas; Winter, Rainer F

    2013-03-01

    The mixed-valent radical cation of a styrylruthenium-modified meso-tetraarylzinc porphyrin forms a mixture of three different valence tautomers (VTs) in CH2Cl2 or 1,2-C2H4Cl2 solutions. One of these VTs has the charge and spin delocalized over the porphyrin and the styrylruthenium moieties, while the other two display charge and spin localization on just one of the different redox sites. The relative amounts of the three different VTs were determined by EPR and IR spectroscopies at variable temperatures, while delocalization in the ground state was confirmed by DFT calculations.

  19. Analysis of orbital occupancy of valence neutron in 15C through Coulomb breakup reactions

    Science.gov (United States)

    Singh, P.

    2015-03-01

    The Coulomb breakup reactions 208Pb(15C, 14C + n)208Pb and 181Ta(15C, 14C + n)181Ta have been studied at 68 and 85 A MeV beam energies, respectively, within the framework of the eikonal approximation to investigate the orbital occupancy of valence neutron in the 15C nucleus. The outcomes of the present work favor 0+ ⊗ 2 s 1/2 as the core-neutron coupling for the ground-state structure with 0.91 as a spectroscopic factor.

  20. Correlation effects in the valence bands of ferromagnetic semiconductor EuS

    OpenAIRE

    Sharma, A; Nolting, W.

    2005-01-01

    We present a many body analysis of the multi-band Kondo lattice model. The study is then combined with the first principles TB-LMTO band structure calculations, in order to investigate the temperature dependent correlation effects in the 3$\\textit{p}$ valence bands of the ferromagnetic semiconductor EuS. Some of the physical properties of interest like the quasi-particle density of states (Q-DOS), spectral density (SD) and quasi-particle band structure (Q-BS) are calculated and discussed. The...

  1. Attosecond time delay in valence photoionization and photorecombination of argon: a TDLDA study

    CERN Document Server

    Magrakvelidze, Maia; Dixit, Gopal; Ivanov, Misha; Chakraborty, Himadri S

    2015-01-01

    We determine and analyze the quantum phases and time delays in photoionization and photorecombination of valence 3p and 3s electrons of argon using the Kohn-Sham local density functional approach. The time-dependent local density approximation (TDLDA) is used to account for the electron correlation. Resulting attosecond Wigner-Smith time delays show excellent agreements with two recent independent experiments on argon that measured the relative 3s-3p time delay in photoionization [Physical Review Letters {\\bf 106}, 143002 (2011)] and the delay in 3p photorecombination [Physical Review Letters {\\bf 112}, 153002 (2014)

  2. Superconductivity without dependence on valence electron density in Zn doped YBCO systems

    Institute of Scientific and Technical Information of China (English)

    Li Ping-Lin; Wang Yong-Yong; Tian Yong-Tao; Wang Jing; Niu Xiao-Li; Wang Jun-Xi; Wang Dan-Dan; Wang Xiao-Xia

    2008-01-01

    This paper reports that the YBa2Cu3-xZnxO7-δ(x=0-0.4)samples are researched by means of x-ray diffraction,calculations of binding energy,the positron experiments and variations of oxygen content.The results of simulated calculations,positron experiments and variations of oxygen content support the existence of cluster effect.Moreover,it is concluded that the cluster effect is an important factor on suppression of high-Tc cuprate superconductivity and the Tc does not depend on the density of valence electron directly.

  3. Valence quark contributions for the gamma N -> P11(1440) form factors

    CERN Document Server

    Ramalho, G

    2010-01-01

    Using a covariant spectator quark model we estimate valence quark contributions to the F1*(Q2) and F2*(Q2) transition form factors for the gamma N -> P11(1440) reaction. The Roper resonance, P11(1440), is assumed to be the first radial excitation of the nucleon. The present model requires no extra parameters except for those already fixed by the previous studies for the nucleon. Our results are consistent with the experimental data in the high Q2 region, and those from lattice QCD. We also estimate the meson cloud contributions, focusing on the low Q2 region, where they are expected to be dominant.

  4. Valence quark contributions for the gamma N -> P11(1440) transition

    Energy Technology Data Exchange (ETDEWEB)

    G. Ramalho, K. Tsushima

    2011-03-01

    A covariant spectator quark model is applied to estimate the valence quark contributions to the$ F1*(Q2) and F2*(Q2) transition form factors for the gamma N -> P11(1440) reaction. The Roper resonance, P11(1440), is assumed to be the first radial excitation of the nucleon. The model requires no extra parameters except for those already fixed by the previous studies for the nucleon. The results are consistent with the experimental data in the high Q2 region, and those from the lattice QCD. Finally the model is also applied to estimate the meson cloud contributions from the CLAS and MAID analysis.

  5. Valence quark contributions for the gamma N -> P11(1440) transition

    CERN Document Server

    Ramalho, G

    2010-01-01

    A covariant spectator quark model is applied to estimate the valence quark contributions to the$ F1*(Q2) and F2*(Q2) transition form factors for the gamma N -> P11(1440) reaction. The Roper resonance, P11(1440), is assumed to be the first radial excitation of the nucleon. The model requires no extra parameters except for those already fixed by the previous studies for the nucleon. The results are consistent with the experimental data in the high Q2 region, and those from the lattice QCD. Finally the model is also applied to estimate the meson cloud contributions from the CLAS and MAID analysis.

  6. The bulk valence state of Fe and the origin of water in chondrites

    Science.gov (United States)

    Sutton, S.; Alexander, C. M. O'D.; Bryant, A.; Lanzirotti, A.; Newville, M.; Cloutis, E. A.

    2017-08-01

    There is abundant petrologic evidence for the oxidation of Fe during the aqueous alteration of chondrites, and water must have been the oxidant for this process. The H2 lost from the chondrite parent bodies as a result of Fe oxidation would have been isotopically very light, enriching any residual water in D. The extents of the D enrichments will have depended on the fractions of water consumed and the temperatures during Fe oxidation. Here we have estimated the likely ranges of water consumed by Fe oxidation in the CI, CM, CR and LL parent bodies, as well as the likely range of changes in water H isotopic compositions this would have produced. We first used Fe XANES to determine the Fe valences of bulk meteorite powders in Orgueil (CI1), a number of CMs and CRs that experienced varying degrees of alteration, and Semarkona (LL3.00). The total ranges of bulk Fe valences we obtained were: Orgueil 2.77, CMs 2.40-2.63, CRs 1.46-2.54, and Semarkona 2.10. Combining previous estimates of the present water/OH contents of our samples with the present bulk Fe valences and an estimated range of initial bulk Fe valences, we estimate the likely ranges of fractional water losses to have been: Orgueil 15-26%, Semarkona 73-83%, CMs 23-48%, and CRs 39-62%. The associated maximum and minimum changes in the H isotopic compositions of the remaining water were estimated assuming the equilibrium H2-H2O isotopic fractionation factor, Rayleigh fractionation of the H2, and oxidation temperatures of 0-200 °C. Using previous estimates of the water H isotopic compositions in the chondrites, the ranges of estimated δD values for the initial chondritic waters are: Orgueil -672‰ to -422‰, CMs -676‰ to -493‰, CRs -527‰ to -56‰, and Semarkona -527‰ to 154‰. The CI, CM, CR and ordinary chondrites all accreted water with similar H isotopic compositions that were distinct from the compositions of comets or Saturn's moon Enceladus. Thus, the carbonaceous chondrites are unlikely to

  7. Studies on the valence electronic structure of Fe and Ni in FeNi1- alloys

    Indian Academy of Sciences (India)

    D K Basa; S Raj; H C Padhi; M Polasik; F Pawlowski

    2002-05-01

    -to- X-ray intensity ratios of Fe and Ni in pure metals and in FeNi1- alloys ( = 0.20, 0.50, 0.58) exhibiting similar crystalline structure have been measured following excitation by 59.54 keV -rays from a 241Am point source, to understand as to why the properties of permalloy Fe0.2Ni0.8 is distinct from other alloy compositions. It is observed that the valence electronic structure of Fe0.2Ni0.8 alloy is totally different from other alloys which may be attributed to its special magnetic properties.

  8. Determination of Technetium-99 in Environmental Samples by Solvent Extraction at Controlled Valence

    DEFF Research Database (Denmark)

    Chen, Q.J.; Aarkrog, A.; Dahlgaard, H.

    1989-01-01

    Distribution coefficients of technetium and ruthenium are determined under different conditions with CCl4, cyclohexanone, and 5% tri-isooctylamine (TIOA)/xylene. A method for analyzing 99Tc in environmental samples has been developed by solvent extraction in which the valences of technetium...... are subsequently separated by solvent extraction with cyclohexanone and 5% TIOA/xylene. The decontamination of the procedure is 1.35 .cntdot. 105 for 103Ru and 1.66 .cntdot. 105 for 110mAg. The chemical yield of technetium-99 is 55%....

  9. Effect of Surface Defect States on Valence Band and Charge Separation and Transfer Efficiency

    Science.gov (United States)

    Xu, Juan; Teng, Yiran; Teng, Fei

    2016-09-01

    Both energy band and charge separation and transfer are the crucial affecting factor for a photochemical reaction. Herein, the BiOCl nanosheets without and with surface bismuth vacancy (BOC, V-BOC) are prepared by a simple hydrothermal method. It is found that the new surface defect states caused by bismuth vacancy have greatly up-shifted the valence band and efficiently enhanced the separation and transfer rates of photogenerated electron and hole. It is amazing that the photocatalytic activity of V-BOC is 13.6 times higher than that of BOC for the degradation methyl orange (MO). We can develop an efficient photocatalyst by the introduction of defects.

  10. The valence electron structure and property analysis of TiC

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The valence electron structure of TiC was calculated by using the empirical electron theory of solids and molecules. The calculated results show that with the increase of temperature the number of common electrons of TiC increases, which indicates that TiC has a good thermal sta-bility; and there exists a close relationship between hardness and brittleness of TiC. According to the number of lattice electrons, the differences among the crystals with different structures can be explained qualitatively. Using the "bond- strengthening factor", the differences of hardness among the crystals with different structures can also be qualitatively explained to some extent.

  11. Valence electron structure of cast iron and graphltization behaviour criterion of elements

    Institute of Scientific and Technical Information of China (English)

    刘志林; 李志林; 孙振国; 杨晓平; 陈敏

    1995-01-01

    The valence electron structure of common alloy elements in phases of cast iron is calculated- The relationship between the electron structure of alloy elements and equilibrium, non-equilibrium solidification and graphitization is revealed by defining the bond energy of the strongest bond in a phase as structure formation factor S. A criterion of graphitization behaviour of elements is advanced with the critical value of the structure formation factor of graphite and the n of the strongest covalent bond in cementite. It is found that this theory conforms to practice very well when the criterion is applied to the common alloy elements.

  12. Forward Rapidity Hadron Production in Deuteron Gold Collisions from Valence Quarks

    CERN Document Server

    Jalilian-Marian, J

    2005-01-01

    We consider hadron production in deuteron gold collisions at RHIC in the forward rapidity region. Treating the target nucleus as a Color Glass Condensate and the projectile deuteron as a dilute system of valence quarks, we obtain good agreement with the BRAHMS minimum bias data on charged hadron production in the forward rapidity ($y=3.2$) and low $p_t$ region. We provide predictions for neutral pion production in minimum bias deuteron gold collisions in the forward rapidity region, $y=3.8$, measured by the STAR collaboration at RHIC.

  13. Experimental and Theoretical Investigation of Valence Orbitals in 1,4-Dioxane by Electron momentum Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    YANG Tie-Cheng; NING Chuan-Gang; SU Guo-Lin; DENG Jing-Kang; ZHANG Shu-Feng; REN Xue-Guang; HUANG Yan-Ru

    2006-01-01

    @@ The binding energy spectrum of all valence orbitals and the momentum distributions of highest occupied molecular orbital (HOMO: 8ag), 7bu + 7ag, 4bu, 2bg + 4ag and 2au in 1, 4-dioxane are investigated by electron momentum spectroscopy (EMS) with 600 e V impact energy. The experimental results are consistent with theoretical calculations of C2h chair conformation using the Hartree-Fock method and density functional theory with 6-311++G**and A UG-CC-PVTZ basis sets.

  14. Empirical valence bond model of an SN2 reaction in polar and nonpolar solvents

    Science.gov (United States)

    Benjamin, Ilan

    2008-08-01

    A new model for the substitution nucleophilic reaction (SN2) in solution is described using the empirical valence bond (EVB) method. The model includes a generalization to three dimensions of a collinear gas phase EVB model developed by Mathis et al. [J. Mol. Liq. 61, 81 (1994)] and a parametrization of solute-solvent interactions of four different solvents (water, ethanol, chloroform, and carbon tetrachloride). The model is used to compute (in these four solvents) reaction free energy profiles, reaction and solvent dynamics, a two-dimensional reaction/solvent free energy map, as well as a number of other properties that in the past have mostly been estimated.

  15. A tutorial for understanding chemical reactivity through the valence bond approach.

    Science.gov (United States)

    Usharani, Dandamudi; Lai, Wenzhen; Li, Chunsen; Chen, Hui; Danovich, David; Shaik, Sason

    2014-07-21

    This is a tutorial on the usage of valence bond (VB) diagrams for understanding chemical reactivity in general, and hydrogen atom transfer (HAT) reactivity in particular. The tutorial instructs the reader how to construct the VB diagrams and how to estimate HAT barriers from raw data, starting with the simplest reaction H + H2 and going all the way to HAT in the enzyme cytochrome P450. Other reactions are treated as well, and some unifying principles are outlined. The tutorial projects the unity of reactivity treatments, following Coulson's dictum "give me insight, not numbers", albeit with its modern twist: giving numbers and insight.

  16. Analysis of orbital occupancy of valence neutron in {sup 15}C through Coulomb breakup reactions

    Energy Technology Data Exchange (ETDEWEB)

    Singh, P., E-mail: panghal005@gmail.com, E-mail: pardeep.phy@dcrustm.org [Deenbandhu Chhotu Ram University of Science and Technology, Department of Physics (India)

    2015-03-15

    The Coulomb breakup reactions {sup 208}Pb({sup 15}C, {sup 14}C + n){sup 208}Pb and {sup 181}Ta({sup 15}C, {sup 14}C + n){sup 181}Ta have been studied at 68 and 85 A MeV beam energies, respectively, within the framework of the eikonal approximation to investigate the orbital occupancy of valence neutron in the {sup 15}C nucleus. The outcomes of the present work favor 0{sup +} ⊗ 2s{sub 1/2} as the core-neutron coupling for the ground-state structure with 0.91 as a spectroscopic factor.

  17. Entanglement and SU(n) symmetry in one-dimensional valence bond solid states

    CERN Document Server

    Orus, Roman

    2011-01-01

    Here we evaluate the many-body entanglement properties of a generalized SU(n) valence bond solid state on a chain. Our results follow from a derivation of the transfer matrix of the system which, in combination with symmetry properties, allows for a new, elegant and straightforward evaluation of different entanglement measures. In particular, the geometric entanglement per block, correlation length, von Neumann and R\\'enyi entropies of a block, localizable entanglement and entanglement length are obtained in a very simple way. All our results are in agreement with previous derivations for the SU(2) case.

  18. Classification model of arousal and valence mental states by EEG signals analysis and Brodmann correlations

    Directory of Open Access Journals (Sweden)

    Adrian Rodriguez Aguinaga

    2015-06-01

    Full Text Available This paper proposes a methodology to perform emotional states classification by the analysis of EEG signals, wavelet decomposition and an electrode discrimination process, that associates electrodes of a 10/20 model to Brodmann regions and reduce computational burden. The classification process were performed by a Support Vector Machines Classification process, achieving a 81.46 percent of classification rate for a multi-class problem and the emotions modeling are based in an adjusted space from the Russell Arousal Valence Space and the Geneva model.

  19. A study of the valence shell electronic structure and photoionisation dynamics of para-dichlorobenzene and para-bromochlorobenzene

    Energy Technology Data Exchange (ETDEWEB)

    Powis, I. [School of Chemistry, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Trofimov, A.B. [Laboratory of Quantum Chemistry, Irkutsk State University, 664003 Irkutsk (Russian Federation); A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, 664033 Irkutsk (Russian Federation); Bodzuk, I.L. [Laboratory of Quantum Chemistry, Irkutsk State University, 664003 Irkutsk (Russian Federation); Holland, D.M.P., E-mail: david.holland@stfc.ac.uk [Daresbury Laboratory, Daresbury, Warrington, Cheshire, WA4 4AD (United Kingdom); Potts, A.W. [Department of Physics, King’s College, Strand, London WC2R 2LS (United Kingdom); Karlsson, L. [Department of Physics, Uppsala University, Box 530, SE-751 21 Uppsala (Sweden)

    2013-03-29

    Highlights: ► Electronic structure and photoionisation dynamics of pDCB and pBCB have been studied. ► Dynamics affected by halogen atom Cooper minimum. ► Many-body effects influence inner valence shell ionisation. - Abstract: The valence shell electronic structure and photoionisation dynamics of para-dichlorobenzene and para-bromochlorobenzene have been investigated both experimentally and theoretically. High resolution photoelectron spectra of the outer valence orbitals have been recorded with HeI radiation and the observed structure has been interpreted using calculated ionisation energies and spectral intensities. The theoretical predictions for the single-hole ionic states due to outer valence ionisation agree satisfactorily with the experimental results. Ionisation from the inner valence orbitals is strongly influenced by many-body effects and the with a particular orbital is spread amongst numerous satellites. Some of the photoelectron bands exhibit vibrational progressions and tentative assignments have been proposed. The photoionisation dynamics of the outer valence orbitals of para-dichlorobenzene have been investigated theoretically by using the continuum multiple scattering approach to calculate photoionisation partial cross-sections and photoelectron anisotropy parameters. The results show that ionisation from some of the orbitals is affected by the Cooper minimum associated with the chlorine atom. Synchrotron radiation has been used to record angle resolved photoelectron spectra of the entire valence shell, for photon energies between threshold and ∼100 eV, and these have allowed the corresponding experimental data to be derived. A comparison between the predicted and measured anisotropy parameters confirms the influence of the Cooper minimum in those orbitals related to the chlorine lone-pairs.

  20. Re-examining the automaticity and directionality of the activation of the spatial-valence "good is up" metaphoric association.

    Directory of Open Access Journals (Sweden)

    Yanli Huang

    Full Text Available According to the Conceptual Metaphor Theory, people understand abstract concepts depending on the activation of more concrete concepts, but not vice versa. The present research aims to investigate the role of directionality and automaticity regarding the activation of the conceptual metaphor "good is up". Experiment 1 tested the automaticity of the spatial-to-valence metaphoric congruency effect by having participants judge the valence of a positive or negative word that appeared either at the top or at the bottom of the screen. They performed the task concurrently with a 6-digit verbal rehearsal task in the working-memory-load (WML blocks and without this task in the non-WML blocks. The spatial-to-valence metaphoric congruency effect occurred for the positive words in the non-WML blocks (i.e., positive words are judged more quickly when they appeared at the top than at the bottom of the screen, but not in the WML blocks, suggesting that this metaphoric association might not be activated automatically. Experiments 2-6 investigated the valence-to-spatial metaphoric association and its automaticity. Participants processed a positive or negative prime, which appeared at the center of the screen, and then identified a letter (p/q that subsequently appeared at the top or bottom of the screen. The valence-to-spatial metaphoric congruency effect did not occur in the WML (6-digit verbal rehearsal or non-WML blocks, whether response modality to the prime was key-press or vocal, or whether the prime was a word or a picture. The effect only unexpectedly occurred when the task was simultaneously performed with a 4-dot-position visuospatial rehearsal task. Nevertheless, the data collapsed across multiple experiments showed a null valence-to-spatial metaphoric congruency effect, suggesting the absence of the valence-to-spatial metaphoric association in general. The implications of the current findings for the Conceptual Metaphor Theory and its alternatives

  1. Coordination Frictions and Job Heterogeneity

    DEFF Research Database (Denmark)

    Kennes, John; le Maire, Christian Daniel

    This paper develops and extends a dynamic, discrete time, job to worker matching model in which jobs are heterogeneous in equilibrium. The key assumptions of this economic environment are (i) matching is directed and (ii) coordination frictions lead to heterogeneous local labor markets. We de- rive...

  2. Terrestrial Coordinate Systems and Frames

    Science.gov (United States)

    Boucher, C.; Murdin, P.

    2000-11-01

    A terrestrial reference system (TRS) is a spatial reference system corotating with the Earth in its DIURNAL MOTION in space. In such a system, the positions of points anchored on the Earth's solid surface have coordinates which have only small variations with time, as a result of geophysical effects (tectonic or tidal deformations; see TECTONICS, EARTH'S INTERIOR, TIDES). A terrestrial reference ...

  3. Archimedes' Principle in General Coordinates

    Science.gov (United States)

    Ridgely, Charles T.

    2010-01-01

    Archimedes' principle is well known to state that a body submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the body. Herein, Archimedes' principle is derived from first principles by using conservation of the stress-energy-momentum tensor in general coordinates. The resulting expression for the force is…

  4. Coordinated Exploration for Grand Challenges

    DEFF Research Database (Denmark)

    Ørding Olsen, Anders; Sofka, Wolfgang; Grimpe, Christoph

    2016-01-01

    on the acceptance and support of important stakeholders. In this study, we suggest that search consortia are more likely to receive funding when they include representatives of stakeholder concerns, so-called advocacy groups. We extend theory on coordinated exploration in joint search by integrating mechanisms from...

  5. Coordinating talk and practical action

    DEFF Research Database (Denmark)

    Oshima, Sae; Streeck, Jürgen

    2015-01-01

    This paper investigates how talk and practical action are coordinated during one type of activity involving professional communication: the service-assessment sequence in hair salons. During this activity, a practical inspection of the haircut must be coupled with sequentially produced verbal act...

  6. Archimedes' Principle in General Coordinates

    Science.gov (United States)

    Ridgely, Charles T.

    2010-01-01

    Archimedes' principle is well known to state that a body submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the body. Herein, Archimedes' principle is derived from first principles by using conservation of the stress-energy-momentum tensor in general coordinates. The resulting expression for the force is…

  7. Coordinating talk and practical action

    DEFF Research Database (Denmark)

    Oshima, Sae; Streeck, Jürgen

    2015-01-01

    . Our analysis of four examples reveals that there is no fixed relationship between the organization of talk and practical action. Instead, people manipulate this relationship on a moment-by-moment basis, often coordinating the two into a single, integral package, or relying on one stream of action...

  8. Early insulin therapy Coordination Council

    Directory of Open Access Journals (Sweden)

    Marina Vladimirovna Shestakova

    2012-12-01

    Full Text Available Coordination Council has denoted the importance of adherence to Russian and international guidelines and prominent role of insulin therapy in management of type 2 diabetes mellitus (T2DM. Insulin therapy in T2DM preserves endogenous insulin secretion, prevents or decelerates development of microvascular complications and is known to be the most effective glucose-lowering treatment.

  9. Modular construction of oxide structures--compositional control of transition metal coordination environments.

    Science.gov (United States)

    Tenailleau, Christophe; Allix, Mathieu; Claridge, John B; Hervieu, Maryvonne; Thomas, Michael F; Hirst, James P; Rosseinsky, Matthew J

    2008-06-18

    The effects of reaction temperature and pO2 were investigated on a series of (Ba,Ca,Nd)FeO3-delta perovskite systems in order to isolate phases containing ordered arrangements of the distinct vacancy and cation ordering patterns identified in less compositionally complex iron oxide systems. Initial synthesis in air at high temperature yields cubic perovskite phases (I) with average iron oxidation states higher than 3; selected area electron diffraction together with diffuse features observed in the synchrotron X-ray diffraction (SXRD) patterns of these materials show evidence of small domains of short-range cation and vacancy order. Annealing these materials in nitrogen or in a sealed tube in the presence of an NiO/Ni buffer yielded the Fe(3+) phase Ca2Ba2Nd2Fe6O16 (II), closely related to Sr2LaFe3O8 but with partial cation order as well as anion order present the larger Ba cations are largely present in the 12-coordinate site between the octahedral iron layers, and Ca is largely present in 10-coordinate sites between octahedral and tetrahedral sites. Further reduction of Ca2Ba2Nd2Fe6O16 using a Zr getter yields the mixed-valence phase Ca2Ba2Nd2Fe6O15.6 (III). The structure of III was solved by maximum entropy analysis of XRD data coupled with analysis of high-temperature neutron diffraction data and refined against combined SXRD and high-Q ambient-temperature neutron data. This material crystallizes in a 20-fold perovskite super cell (Imma, a approximately square root(2 x a(p), b approximately 10 x a(p), c approximately square root(x 2a(p)) and can be visualized as an intergrowth between brownmillerite (Ca2Fe2O5) and the YBa2Fe3O8 structure. There are three distinct iron coordination environments, octahedral (O), square-pyramidal (Sp), and trigonal planar (Tp, formed by distorting the tetrahedral site in brownmillerite), which form a Sp-O-Tp-O-Sp repeat. Bond valence calculations indicate that Tp is an Fe(2+) site, while the O and Sp sites are Fe(3+). The A

  10. Valence band offsets at Cu(In,Ga)Se{sub 2}/Zn(O,S) interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Adler, Tobias; Klein, Andreas [Surface Science Division, Institute of Materials Science, Technische Universitaet Darmstadt, Petersenstrasse 32, 64287, Darmstadt (Germany); Botros, Miriam [Surface Science Division, Institute of Materials Science, Technische Universitaet Darmstadt, Petersenstrasse 32, 64287, Darmstadt (Germany); Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Industriestrasse 6, 70565, Stuttgart (Germany); Witte, Wolfram; Hariskos, Dimitrios; Menner, Richard; Powalla, Michael [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Industriestrasse 6, 70565, Stuttgart (Germany)

    2014-09-15

    The energy band alignment at interfaces between Cu-chalcopyrites and Zn(O,S) buffer layers, which are important for thin-film solar cells, are considered. Valence band offsets derived from X-ray photoelectron spectroscopy for Cu(In,Ga)Se{sub 2} absorber layers with CdS and Zn(O,S) compounds are compared to theoretical predictions. It is shown that the valence band offsets at Cu(In,Ga)Se{sub 2}/Zn(O,S) interfaces approximately follow the theoretical prediction and vary significantly from sample to sample. The integral sulfide content of chemical bath deposited Zn(O,S) is reproducibly found to be 50-70%, fortuitously resulting in a conduction band offset suitable for solar cell applications with Cu(In,Ga)Se{sub 2} absorber materials. The observed variation in offset can neither be explained by variation of the Cu content in the Cu(In,Ga)Se{sub 2} near the interface nor by local variation of the chemical composition. Fermi level pinning induced by high defect concentrations is a possible origin of the variation of band offset. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Resonant valence bond states in zinc vacancies induce the ferromagnetism of ZnO

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Shih-Jye, E-mail: sjs@nuk.edu.tw

    2016-05-06

    A theoretical model was proposed to investigate the mechanism of ferromagnetism in ZnO as well as to simulate the experimental result that the ferromagnetism can be enhanced by UV irradiation as UV photon energy is equivalent to the band gap. In the model, the spin moments arise from the trapped electrons in oxygen vacancy states and coexist with the itinerant electrons which reside in zinc vacancy states and fall into resonant valence bond states. Charge exchange between the conduction band of ZnO and both vacancy states makes electrons on both vacancy states delocalized and results in a decrease of the ferromagnetism as well. - Highlights: • The spin moments of ZnO arise from the electrons trapped in oxygen vacancies. • The itinerant electrons residing in zinc vacancies fall into resonant valence bond states. • The ferromagnetism of ZnO is present as both oxygen and zinc vacancies are coexisting. • The couplings between the conduction band and both vacancy states both make the ferromagnetism decrease.

  12. Convergence of valence bands for high thermoelectric performance for p-type InN

    Science.gov (United States)

    Li, Hai-Zhu; Li, Ruo-Ping; Liu, Jun-Hui; Huang, Ming-Ju

    2015-12-01

    Band engineering to converge the bands to achieve high valley degeneracy is one of effective approaches for designing ideal thermoelectric materials. Convergence of many valleys in the valence band may lead to a high Seebeck coefficient, and induce promising thermoelectric performance of p-type InN. In the current work, we have systematically investigated the electronic structure and thermoelectric performance of wurtzite InN by using the density functional theory combined with semiclassical Boltzmann transport theory. Form the results, it can be found that intrinsic InN has a large Seebeck coefficient (254 μV/K) and the largest value of ZeT is 0.77. The transport properties of p-type InN are better than that of n-type one at the optimum carrier concentration, which mainly due to the large Seebeck coefficient for p-type InN, although the electrical conductivity of n-type InN is larger than that of p-type one. We found that the larger Seebeck coefficient for p-type InN may originate from the large valley degeneracy in the valence band. Moreover, the low minimum lattice thermal conductivity for InN is one key factor to become a good thermoelectric material. Therefore, p-type InN could be a potential material for further applications in the thermoelectric area.

  13. Interference Conditions of the Reconsolidation Process in Humans: The Role of Valence and Different Memory Systems

    Science.gov (United States)

    Fernández, Rodrigo S.; Bavassi, Luz; Kaczer, Laura; Forcato, Cecilia; Pedreira, María E.

    2016-01-01

    Following the presentation of a reminder, consolidated memories become reactivated followed by a process of re-stabilization, which is referred to as reconsolidation. The most common behavioral tool used to reveal this process is interference produced by new learning shortly after memory reactivation. Memory interference is defined as a decrease in memory retrieval, the effect is generated when new information impairs an acquired memory. In general, the target memory and the interference task used are the same. Here we investigated how different memory systems and/or their valence could produce memory reconsolidation interference. We showed that a reactivated neutral declarative memory could be interfered by new learning of a different neutral declarative memory. Then, we revealed that an aversive implicit memory could be interfered by the presentation of a reminder followed by a threatening social event. Finally, we showed that the reconsolidation of a neutral declarative memory is unaffected by the acquisition of an aversive implicit memory and conversely, this memory remains intact when the neutral declarative memory is used as interference. These results suggest that the interference of memory reconsolidation is effective when two task rely on the same memory system or both evoke negative valence. PMID:28066212

  14. Valence and conduction band structure of the quasi-two-dimensional semiconductor Sn S2

    Science.gov (United States)

    Racke, David A.; Neupane, Mahesh R.; Monti, Oliver L. A.

    2016-02-01

    We present the momentum-resolved photoemission spectroscopy of both the valence and the conduction band region in the quasi-two-dimensional van der Waals-layered indirect band gap semiconductor Sn S2 . Using a combination of angle-resolved ultraviolet photoemission and angle-resolved two-photon photoemission (AR-2PPE) spectroscopy, we characterize the band structure of bulk Sn S2 . Comparison with density functional theory calculations shows excellent quantitative agreement in the valence band region and reveals several localized bands that likely originate from defects such as sulfur vacancies. Evidence for a moderate density of defects is also observed by AR-2PPE in the conduction band region, leading to localized bands not present in the computational results. The energetic structure and dispersion of the conduction bands is captured well by the computational treatment, with some quantitative discrepancies remaining. Our results provide a broader understanding of the electronic structure of Sn S2 in particular and van der Waals-layered semiconductors in general.

  15. Dorsal striatum responses to reward and punishment: effects of valence and magnitude manipulations.

    Science.gov (United States)

    Delgado, M R; Locke, H M; Stenger, V A; Fiez, J A

    2003-03-01

    The goal of this research was to further our understanding of how the striatum responds to the delivery of affective feedback. Previously, we had found that the striatum showed a pattern of sustained activation after presentation of a monetary reward, in contrast to a decrease in the hemodynamic response after a punishment. In this study, we tested whether the activity of the striatum could be modulated by parametric variations in the amount of financial reward or punishment. We used an event-related fMRI design in which participants received large or small monetary rewards or punishments after performance in a gambling task. A parametric ordering of conditions was observed in the dorsal striatum according to both magnitude and valence. In addition, an early response to the presentation of feedback was observed and replicated in a second experiment with increased temporal resolution. This study further implicates the dorsal striatum as an integral component of a reward circuitry responsible for the control of motivated behavior, serving to code for such feedback properties as valence and magnitude.

  16. Z2 gauge theory for valence bond solids on the kagome lattice

    Science.gov (United States)

    Hwang, Kyusung; Huh, Yejin; Kim, Yong Baek

    We present an effective Z2 gauge theory that captures various competing phases in spin-1/2 kagome lattice antiferromagnets: the topological Z2 spin liquid (SL) phase, and the 12-site and 36- site valence bond solid (VBS) phases. Our effective theory is a generalization of the recent Z2 gauge theory proposed for SL phases by Wan and Tchernyshyov. In particular, we investigate possible VBS phases that arise from vison condensations in the SL. In addition to the 12-site and 36-site VBS phases, there exists 6-site VBS that is closely related to the symmetry-breaking valence bond modulation patterns observed in the recent density matrix renormalization group simulations. We find that our results have remarkable consistency with a previous study using a different Z2 gauge theory. Motivated by the lattice geometry in the recently reported vanadium oxyfluoride kagome antiferromagnet, our gauge theory is extended to incorporate lowered symmetry by inequivalent up- and down-triangles. We investigate effects of this anisotropy on the 12-site, 36-site, and 6-site VBS phases. Particularly, interesting dimer melting effects are found in the 36-site VBS. We discuss the implications of our findings and also compare the results with a different type of Z2 gauge theory used in previous studies.

  17. The effect of cerium valence states at cerium oxide nanoparticle surfaces on cell proliferation

    KAUST Repository

    Naganuma, Tamaki

    2014-05-01

    Understanding and controlling cell proliferation on biomaterial surfaces is critical for scaffold/artificial-niche design in tissue engineering. The mechanism by which underlying integrin ligates with functionalized biomaterials to induce cell proliferation is still not completely understood. In this study, poly-l-lactide (PL) scaffold surfaces were functionalized using layers of cerium oxide nanoparticles (CNPs), which have recently attracted attention for use in therapeutic application due to their catalytic ability of Ce4+ and Ce3+ sites. To isolate the influence of Ce valance states of CNPs on cell proliferation, human mesenchymal stem cells (hMSCs) and osteoblast-like cells (MG63) were cultured on the PL/CNP surfaces with dominant Ce4+ and Ce3+ regions. Despite cell type (hMSCs and MG63 cells), different surface features of Ce4+ and Ce3+ regions clearly promoted and inhibited cell spreading, migration and adhesion behavior, resulting in rapid and slow cell proliferation, respectively. Cell proliferation results of various modified CNPs with different surface charge and hydrophobicity/hydrophilicity, indicate that Ce valence states closely correlated with the specific cell morphologies and cell-material interactions that trigger cell proliferation. This finding suggests that the cell-material interactions, which influence cell proliferation, may be controlled by introduction of metal elements with different valence states onto the biomaterial surface. © 2014 Elsevier Ltd.

  18. Valence and L-shell photoionization of Cl-like Argon using R-matrix techniques

    CERN Document Server

    Tyndall, Niall; Ballance, Connor; Hibbert, Alan

    2015-01-01

    Photoionization cross sections are obtained using the relativistic Dirac Atomic R-matrix Codes (DARC) for all valence and L-shell energy ranges between 27-270eV. A total of 557 levels arising from the dominant configurations 3s$^2$3p$^4$, 3s3p$^5$, 3p$^6$, 3s$^2$3p$^3$[3d, 4s, 4p], 3p$^5$3d, 3s$^2$3p$^2$3d$^2$, 3s3p$^4$3d, 3s3p$^3$3d$^2$ and 2s$^2$2p$^5$3s$^2$3p$^5$ have been included in the target wavefunction representation of the Ar III ion, including up to 4p in the orbital basis. We also performed a smaller Breit-Pauli (BP) calculation containing the lowest 124 levels. Direct comparisons are made with previous theoretical and experimental work for both valence shell and L-shell photoionization. Excellent agreement was found for transitions involving the $^2$P$^{\\rm o}$ initial state to all allowed final states for both calculations across a range of photon energies. A number of resonant states have been identified to help analyze and explain the nature of the spectra at photon energies between 250 and 27...

  19. Lateralized goal framing: How health messages are influenced by valence and contextual/analytic processing.

    Science.gov (United States)

    McCormick, Michael; Seta, John J

    2016-05-01

    The effectiveness of health messages has been shown to vary due to the positive or negative framing of information, often known as goal framing. In two experiments we altered, the strength of the goal framing manipulation by selectively activating the processing style of the left or right hemisphere (RH). In Experiment 1, we found support for the contextual/analytic perspective; a significant goal framing effect was observed when the contextual processing style of the RH - but not the analytic processing style of the left hemisphere (LH) - was initially activated. In Experiment 2, support for the valence hypothesis was found when a message that had a higher level of personal involvement was used than that in Experiment 1. When the LH was initially activated, there was an advantage for the gain- vs. loss-framed message; however, an opposite pattern - an advantage for the loss-framed message - was obtained when the RH was activated. These are the first framing results that support the valence hypothesis. We discuss the theoretical and applied implications of these experiments.

  20. Effects of gaze direction, head orientation and valence of facial expression on amygdala activity.

    Science.gov (United States)

    Sauer, Andreas; Mothes-Lasch, Martin; Miltner, Wolfgang H R; Straube, Thomas

    2014-08-01

    There is increasing evidence for a role of the amygdala in processing gaze direction and emotional relevance of faces. In this event-related functional magnetic resonance study we investigated amygdala responses while we orthogonally manipulated head direction, gaze direction and facial expression (angry, happy and neutral). This allowed us to investigate effects of stimulus ambiguity, low-level factors and non-emotional factors on amygdala activation. Averted vs direct gaze induced increased activation in the right dorsal amygdala regardless of facial expression and head orientation. Furthermore, valence effects were found in the ventral amygdala and strongly dependent on head orientation. We observed enhanced activation to angry and neutral vs happy faces for observer-directed faces in the left ventral amygdala while the averted head condition reversed this pattern resulting in increased activation to happy as compared to angry and neutral faces. These results suggest that gaze direction drives specifically dorsal amygdala activation regardless of facial expression, low-level perceptual factors or stimulus ambiguity. The role of the amygdala is thus not restricted to the detection of potential threat, but has a more general role in attention processes. Furthermore, valence effects are associated with activation of the ventral amygdala and strongly influenced by non-emotional factors.

  1. Time-resolved four-wave-mixing spectroscopy for inner-valence transitions.

    Science.gov (United States)

    Ding, Thomas; Ott, Christian; Kaldun, Andreas; Blättermann, Alexander; Meyer, Kristina; Stooss, Veit; Rebholz, Marc; Birk, Paul; Hartmann, Maximilian; Brown, Andrew; Van Der Hart, Hugo; Pfeifer, Thomas

    2016-02-15

    Noncollinear four-wave-mixing (FWM) techniques at near-infrared (NIR), visible, and ultraviolet frequencies have been widely used to map vibrational and electronic couplings, typically in complex molecules. However, correlations between spatially localized inner-valence transitions among different sites of a molecule in the extreme ultraviolet (XUV) spectral range have not been observed yet. As an experimental step toward this goal, we perform time-resolved FWM spectroscopy with femtosecond NIR and attosecond XUV pulses. The first two pulses (XUV-NIR) coincide in time and act as coherent excitation fields, while the third pulse (NIR) acts as a probe. As a first application, we show how coupling dynamics between odd- and even-parity, inner-valence excited states of neon can be revealed using a two-dimensional spectral representation. Experimentally obtained results are found to be in good agreement with ab initio time-dependent R-matrix calculations providing the full description of multielectron interactions, as well as few-level model simulations. Future applications of this method also include site-specific probing of electronic processes in molecules.

  2. Charge transfer and mixed-valence behavior in phtalocyanine-dimer cations.

    Science.gov (United States)

    Monari, Antonio; Evangelisti, Stefano; Leininger, Thierry

    2010-09-28

    Phtalocyanine compounds deserved a considerable interest in recent times, particularly because of their possible use in the field of nanoelectronics. In particular, the charge mobility (of both electrons and holes) in phtalocyanine stacked arrangements has been recently extensively investigated. The present work focuses on the study of the hole-transfer mechanism between two phtalocyanine monomers. For an interdisk distance larger than 4.5 bohrs, the eclipsed dimer exhibits a mixed-valence behavior, with a saddle point transition state separating two equivalent minima. This behavior, however, is strongly dependent on the relative angle between the disks. In particular, the mixed-valence character of the compound is strongly enhanced for arrangements that are far from the eclipsed geometry. Moreover, for values of the angle close to π/8 and 3π/8, the ground and excited transition states have exactly the same energy, thus implying the presence of a conical intersection. These results can have deep implication in the charge transfer along phtalocyanine chains.

  3. Time-resolved four-wave-mixing spectroscopy for inner-valence transitions

    CERN Document Server

    Ding, Thomas; Kaldun, Andreas; Blättermann, Alexander; Meyer, Kristina; Stooß, Veit; Rebholz, Marc; Birk, Paul; Hartmann, Maximilian; Brown, Andrew; Van Der Hart, Hugo; Pfeifer, Thomas

    2015-01-01

    Non-collinear four-wave mixing (FWM) techniques at near-infrared (NIR), visible, and ultraviolet frequencies have been widely used to map vibrational and electronic couplings, typically in complex molecules. However, correlations between spatially localized inner-valence transitions among different sites of a molecule in the extreme ultraviolet (XUV) spectral range have not been observed yet. As an experimental step towards this goal we perform time-resolved FWM spectroscopy with femtosecond NIR and attosecond XUV pulses. The first two pulses (XUV-NIR) coincide in time and act as coherent excitation fields, while the third pulse (NIR) acts as a probe. As a first application we show how coupling dynamics between odd- and even-parity inner-valence excited states of neon can be revealed using a two-dimensional spectral representation. Experimentally obtained results are found to be in good agreement with ab initio time-dependent R-matrix calculations providing the full description of multi-electron interactions,...

  4. Relationship Between Iron Valence States of Serpentine in CM Chondrites and Their Aqueous Alteration Degrees

    Science.gov (United States)

    Mikouchi, T.; Zolensky, M.; Satake, W.; Le, L.

    2012-01-01

    The 0.6-0.7 micron absorption band observed for C-type asteroids is caused by the presence of Fe(3+) in phyllosilicates . Because Fe-bearing phyllosilicates, especially serpentine, are the most dominant product of aqueous alteration in the most abundant carbonaceous chondrites, CM chondrites, it is important to understand the crystal chemistry of serpentine in CM chondrites to better understand spectral features of C-type asteroids. CM chondrites show variable degrees of aqueous alteration, which should be related to iron valences in serpentine. It is predicted that the Fe(3+)/Sum of (Fe) ratios of serpentine in CM chondrites decrease as alteration proceeds by Si and Fe(3+) substitutions from end-member cronstedtite to serpentine, which should be apparent in the absorption intensity of the 0.6-0.7 micron band from C-type asteroids. In fact, the JAXA Hayabusa 2 target (C-type asteroid: 1993 JU3) exhibits heterogeneous spectral features (0.7 micron absorption band disappears by rotation). From these points of view, we have analyzed iron valences of matrix serpentine in several CM chondrites which span the entire observed range of aqueous alteration using Synchrotron Radiation X-ray Absorption Near-Edge Structure (SR-XANES). In this abstract we discuss the relationship between obtained Fe(3+)/Sum of (Fe) ratios and alteration degrees by adding new data to our previous studies

  5. Additive effects of threat-of-shock and picture valence on startle reflex modulation.

    Directory of Open Access Journals (Sweden)

    Florian Bublatzky

    Full Text Available The present study examined the effects of sustained anticipatory anxiety on the affective modulation of the eyeblink startle reflex. Towards this end, pleasant, neutral and unpleasant pictures were presented as a continuous stream during alternating threat-of-shock and safety periods, which were cued by colored picture frames. Orbicularis-EMG to auditory startle probes and electrodermal activity were recorded. Previous findings regarding affective picture valence and threat-of-shock modulation were replicated. Of main interest, anticipating aversive events and viewing affective pictures additively modulated defensive activation. Specifically, despite overall potentiated startle blink magnitude in threat-of-shock conditions, the startle reflex remained sensitive to hedonic picture valence. Finally, skin conductance level revealed sustained sympathetic activation throughout the entire experiment during threat- compared to safety-periods. Overall, defensive activation by physical threat appears to operate independently from reflex modulation by picture media. The present data confirms the importance of simultaneously manipulating phasic-fear and sustained-anxiety in studying both normal and abnormal anxiety.

  6. Modelling of Ion Transport in Solids with a General Bond Valence Based Force-Field

    Directory of Open Access Journals (Sweden)

    S. Adams

    2010-12-01

    Full Text Available Empirical bond length - bond valence relations provide insight into the link between structure of and ion transport in solid electrolytes. Building on our earlier systematic adjustment of bond valence (BV parameters to the bond softness, here we discuss how the squared BV mismatch can be linked to the absolute energy scale and used as a general Morse-type interaction potential for analyzing low-energy pathways in ion conducting solid or mixed conductors either by an energy landscape approach or by molecular dynamics (MD simulations. For a wide range of Lithium oxides we could thus model ion transport revealing significant differences to an earlier geometric approach. Our novel BV-based force-field has also been applied to investigate a range of mixed conductors, focusing on cathode materials for lithium ion battery (LIB applications to promote a systematic design of LIB cathodes that combine high energy density with high power density. To demonstrate the versatility of the new BV-based force-field it is applied in exploring various strategies to enhance the power performance of safe low cost LIB materials (LiFePO4, LiVPO4F, LiFeSO4F, etc..

  7. Arousal-But Not Valence-Reduces False Memories at Retrieval.

    Directory of Open Access Journals (Sweden)

    Chiara Mirandola

    Full Text Available Mood affects both memory accuracy and memory distortions. However, some aspects of this relation are still poorly understood: (1 whether valence and arousal equally affect false memory production, and (2 whether retrieval-related processes matter; the extant literature typically shows that mood influences memory performance when it is induced before encoding, leaving unsolved whether mood induced before retrieval also impacts memory. We examined how negative, positive, and neutral mood induced before retrieval affected inferential false memories and related subjective memory experiences. A recognition-memory paradigm for photographs depicting script-like events was employed. Results showed that individuals in both negative and positive moods-similar in arousal levels-correctly recognized more target events and endorsed fewer false memories (and these errors were linked to remember responses less frequently, compared to individuals in neutral mood. This suggests that arousal (but not valence predicted memory performance; furthermore, we found that arousal ratings provided by participants were more adequate predictors of memory performance than their actual belonging to either positive, negative or neutral mood groups. These findings suggest that arousal has a primary role in affecting memory, and that mood exerts its power on true and false memory even when induced at retrieval.

  8. Synthesis of High Valence Silver-Loaded Mesoporous Silica with Strong Antibacterial Properties

    Science.gov (United States)

    Chen, Chun-Chi; Wu, Hsin-Hsien; Huang, Hsin-Yi; Liu, Chen-Wei; Chen, Yi-Ning

    2016-01-01

    A simple chemical method was developed for preparing high valence silver (Ag)-loaded mesoporous silica (Ag-ethylenediaminetetraacetic acid (EDTA)-SBA-15), which showed strong antibacterial activity. Ag-EDTA-SBA-15 exhibited stronger and more effective antibacterial activity than commercial Ag nanoparticles did, and it offered high stability of high valence silver in the porous matrix and long-lasting antibacterial activity. The synthesized materials were characterized using Fourier transform infrared spectroscopy, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) analysis, and transmission electron microscopy (TEM). Ag existed in both surface complexation and Ag particles. EDTA anchored within a porous structure chelated Ag ions in higher oxidation states and prevented their agglomeration and oxidation reduction. The XRD results showed that most Ag in the Ag-EDTA-SBA-15 existed in higher oxidation states such as Ag(II) and Ag(III). However, the XPS and TEM results showed that Ag easily reduced in lower oxidation states and agglomerated as Ag particles on the exterior layer of the SBA-15. PMID:26742050

  9. Synthesis of High Valence Silver-Loaded Mesoporous Silica with Strong Antibacterial Properties

    Directory of Open Access Journals (Sweden)

    Chun-Chi Chen

    2016-01-01

    Full Text Available A simple chemical method was developed for preparing high valence silver (Ag-loaded mesoporous silica (Ag-ethylenediaminetetraacetic acid (EDTA-SBA-15, which showed strong antibacterial activity. Ag-EDTA-SBA-15 exhibited stronger and more effective antibacterial activity than commercial Ag nanoparticles did, and it offered high stability of high valence silver in the porous matrix and long-lasting antibacterial activity. The synthesized materials were characterized using Fourier transform infrared spectroscopy, powder X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS analysis, and transmission electron microscopy (TEM. Ag existed in both surface complexation and Ag particles. EDTA anchored within a porous structure chelated Ag ions in higher oxidation states and prevented their agglomeration and oxidation reduction. The XRD results showed that most Ag in the Ag-EDTA-SBA-15 existed in higher oxidation states such as Ag(II and Ag(III. However, the XPS and TEM results showed that Ag easily reduced in lower oxidation states and agglomerated as Ag particles on the exterior layer of the SBA-15.

  10. Stress and emotional valence effects on children's versus adolescents' true and false memory.

    Science.gov (United States)

    Quas, Jodi A; Rush, Elizabeth B; Yim, Ilona S; Edelstein, Robin S; Otgaar, Henry; Smeets, Tom

    2016-01-01

    Despite considerable interest in understanding how stress influences memory accuracy and errors, particularly in children, methodological limitations have made it difficult to examine the effects of stress independent of the effects of the emotional valence of to-be-remembered information in developmental populations. In this study, we manipulated stress levels in 7-8- and 12-14-year-olds and then exposed them to negative, neutral, and positive word lists. Shortly afterward, we tested their recognition memory for the words and false memory for non-presented but related words. Adolescents in the high-stress condition were more accurate than those in the low-stress condition, while children's accuracy did not differ across stress conditions. Also, among adolescents, accuracy and errors were higher for the negative than positive words, while in children, word valence was unrelated to accuracy. Finally, increases in children's and adolescents' cortisol responses, especially in the high-stress condition, were related to greater accuracy but not false memories and only for positive emotional words. Findings suggest that stress at encoding, as well as the emotional content of to-be-remembered information, may influence memory in different ways across development, highlighting the need for greater complexity in existing models of true and false memory formation.

  11. Synthesis of High Valence Silver-Loaded Mesoporous Silica with Strong Antibacterial Properties.

    Science.gov (United States)

    Chen, Chun-Chi; Wu, Hsin-Hsien; Huang, Hsin-Yi; Liu, Chen-Wei; Chen, Yi-Ning

    2016-01-04

    A simple chemical method was developed for preparing high valence silver (Ag)-loaded mesoporous silica (Ag-ethylenediaminetetraacetic acid (EDTA)-SBA-15), which showed strong antibacterial activity. Ag-EDTA-SBA-15 exhibited stronger and more effective antibacterial activity than commercial Ag nanoparticles did, and it offered high stability of high valence silver in the porous matrix and long-lasting antibacterial activity. The synthesized materials were characterized using Fourier transform infrared spectroscopy, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) analysis, and transmission electron microscopy (TEM). Ag existed in both surface complexation and Ag particles. EDTA anchored within a porous structure chelated Ag ions in higher oxidation states and prevented their agglomeration and oxidation reduction. The XRD results showed that most Ag in the Ag-EDTA-SBA-15 existed in higher oxidation states such as Ag(II) and Ag(III). However, the XPS and TEM results showed that Ag easily reduced in lower oxidation states and agglomerated as Ag particles on the exterior layer of the SBA-15.

  12. Organ donation video messaging: differential appeal, emotional valence, and behavioral intention.

    Science.gov (United States)

    Rodrigue, J R; Fleishman, A; Vishnevsky, T; Fitzpatrick, S; Boger, M

    2014-10-01

    Video narratives increasingly are used to draw the public's attention to the need for more registered organ donors. We assessed the differential impact of donation messaging videos on appeal, emotional valence, and organ donation intentions in 781 non-registered adults. Participants watched six videos (four personal narratives, one informational video without personal narrative, and one unrelated to donation) with or without sound (subtitled), randomly sequenced to minimize order effects. We assessed appeal, emotional valence, readiness to register as organ donors, and donation information-seeking behavior. Compared to other video types, one featuring a pediatric transplant recipient (with or without sound) showed more favorable appeal (p organ donor willingness (p donation website after viewing all six videos. Minority race (OR = 1.94, 95% CI = 1.20, 3.13, p = 0.006), positive change in organ donor readiness (OR = 0.26, 95% CI = 0.14, 0.48, p donation website. Brief, one-min videos can have a very dramatic and positive impact on willingness to consider donation and behavioral intentions to register as an organ donor. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Personality modulates the effects of emotional arousal and valence on brain activation.

    Science.gov (United States)

    Kehoe, Elizabeth G; Toomey, John M; Balsters, Joshua H; Bokde, Arun L W

    2012-10-01

    The influence of personality on the neural correlates of emotional processing is still not well characterized. We investigated the relationship between extraversion and neuroticism and emotional perception using functional magnetic resonance imaging (fMRI) in a group of 23 young, healthy women. Using a parametric modulation approach, we examined how the blood oxygenation level dependent (BOLD) signal varied with the participants' ratings of arousal and valence, and whether levels of extraversion and neuroticism were related to these modulations. In particular, we wished to test Eysenck's biological theory of personality, which links high extraversion to lower levels of reticulothalamic-cortical arousal, and neuroticism to increased reactivity of the limbic system and stronger reactions to emotional arousal. Individuals high in neuroticism demonstrated reduced sustained activation in the orbitofrontal cortex (OFC) and attenuated valence processing in the right temporal lobe while viewing emotional images, but an increased BOLD response to emotional arousal in the right medial prefrontal cortex (mPFC). These results support Eysenck's theory, as well as our hypothesis that high levels of neuroticism are associated with attenuated reward processing. Extraversion was inversely related to arousal processing in the right cerebellum, but positively associated with arousal processing in the right insula, indicating that the relationship between extraversion and arousal is not as simple as that proposed by Eysenck.

  14. Empirical valence bond models for reactive potential energy surfaces: a parallel multilevel genetic program approach.

    Science.gov (United States)

    Bellucci, Michael A; Coker, David F

    2011-07-28

    We describe a new method for constructing empirical valence bond potential energy surfaces using a parallel multilevel genetic program (PMLGP). Genetic programs can be used to perform an efficient search through function space and parameter space to find the best functions and sets of parameters that fit energies obtained by ab initio electronic structure calculations. Building on the traditional genetic program approach, the PMLGP utilizes a hierarchy of genetic programming on two different levels. The lower level genetic programs are used to optimize coevolving populations in parallel while the higher level genetic program (HLGP) is used to optimize the genetic operator probabilities of the lower level genetic programs. The HLGP allows the algorithm to dynamically learn the mutation or combination of mutations that most effectively increase the fitness of the populations, causing a significant increase in the algorithm's accuracy and efficiency. The algorithm's accuracy and efficiency is tested against a standard parallel genetic program with a variety of one-dimensional test cases. Subsequently, the PMLGP is utilized to obtain an accurate empirical valence bond model for proton transfer in 3-hydroxy-gamma-pyrone in gas phase and protic solvent.

  15. Positive Affect and Cognitive Restoration: Investigating the Role of Valence and Arousal.

    Directory of Open Access Journals (Sweden)

    Logan J Nealis

    Full Text Available Positive moods are thought to restore self-control resources following depletion. However, it is not well understood whether this effect is due to affective valence (pleasantness, arousal (activation, or a combination of both. Across four studies, we set out to investigate the role of positive moods on cognitive and behavioral measures of self-regulation in an ego-depletion paradigm. In studies 1 and 2, we independently manipulated affective valence and arousal and assessed self-regulation with a Stroop task. Results did not suggest a restorative effect of either on cognitive resources. In study 3, we employed both behavioral (the 'handgrip task' and cognitive (Stroop assessments of self-regulation. Again, no significant effect of mood was observed on the Stroop task. Additionally, participants did not persist significantly longer on the handgrip task following a positive mood induction. Finally, in study 4, high vs. low states of arousal were manipulated and self-regulation was assessed via pre- and post-manipulation Stroop performance. In study 4, Stroop performance improved slightly more across time points for those in the high arousal condition than for those in the low arousal condition. Therefore, across four studies, we failed to find a consistent pattern of results suggesting that positive moods restore cognitive resources.

  16. Embodied simulation of emotional valence: Facial muscle responses to abstract and concrete words.

    Science.gov (United States)

    Künecke, Janina; Sommer, Werner; Schacht, Annekathrin; Palazova, Marina

    2015-12-01

    Semantic knowledge is thought to be at least partially grounded in sensory, motor, and affective information, acquired through experiences in our inner and outer world. The reactivation of experience-related information during meaning access is called simulation. In the affective simulation account, it is assumed that the grounding information depends on the concepts' concreteness. Whereas abstract concepts are thought to be mainly represented through affective experiential information, concrete words rely more on sensory-motor experiential information. To test this hypothesis, we measured facial muscle activity as an indicator of affective simulation during visual word recognition. Words varied on the dimensions of concreteness and valence. Behavioral and electromyographic data were analyzed with linear mixed-effects models with maximal random effect structure to optimize generalization over participants and word samples. Contrary to this hypothesis, we found a valence effect in the m. corrugator supercilii only in response to concrete but not to abstract words. Our data show that affective simulation as measured with facial muscle activity occurs in response to concrete rather than to abstract words. More concrete words are supposed to have higher context availability and richer visual imagery, which might promote affective simulation on the expressive level of facial muscle activity. The results are in line with embodied accounts of semantic representation but speak against its predominant role for representing affective information in abstract concepts.

  17. Priming for performance: valence of emotional primes interact with dissociable prototype learning systems.

    Directory of Open Access Journals (Sweden)

    Marissa A Gorlick

    Full Text Available Arousal Biased Competition theory suggests that arousal enhances competitive attentional processes, but makes no strong claims about valence effects. Research suggests that the scope of enhanced attention depends on valence with negative arousal narrowing and positive arousal broadening attention. Attentional scope likely affects declarative-memory-mediated and perceptual-representation-mediated learning systems differently, with declarative-memory-mediated learning depending on narrow attention to develop targeted verbalizable rules, and perceptual-representation-mediated learning depending on broad attention to develop a perceptual representation. We hypothesize that negative arousal accentuates declarative-memory-mediated learning and attenuates perceptual-representation-mediated learning, while positive arousal reverses this pattern. Prototype learning provides an ideal test bed as dissociable declarative-memory and perceptual-representation systems mediate two-prototype (AB and one-prototype (AN prototype learning, respectively, and computational models are available that provide powerful insights on cognitive processing. As predicted, we found that negative arousal narrows attentional focus facilitating AB learning and impairing AN learning, while positive arousal broadens attentional focus facilitating AN learning and impairing AB learning.

  18. Priming for performance: valence of emotional primes interact with dissociable prototype learning systems.

    Science.gov (United States)

    Gorlick, Marissa A; Maddox, W Todd

    2013-01-01

    Arousal Biased Competition theory suggests that arousal enhances competitive attentional processes, but makes no strong claims about valence effects. Research suggests that the scope of enhanced attention depends on valence with negative arousal narrowing and positive arousal broadening attention. Attentional scope likely affects declarative-memory-mediated and perceptual-representation-mediated learning systems differently, with declarative-memory-mediated learning depending on narrow attention to develop targeted verbalizable rules, and perceptual-representation-mediated learning depending on broad attention to develop a perceptual representation. We hypothesize that negative arousal accentuates declarative-memory-mediated learning and attenuates perceptual-representation-mediated learning, while positive arousal reverses this pattern. Prototype learning provides an ideal test bed as dissociable declarative-memory and perceptual-representation systems mediate two-prototype (AB) and one-prototype (AN) prototype learning, respectively, and computational models are available that provide powerful insights on cognitive processing. As predicted, we found that negative arousal narrows attentional focus facilitating AB learning and impairing AN learning, while positive arousal broadens attentional focus facilitating AN learning and impairing AB learning.

  19. Interference conditions of the reconsolidation process in humans: the role of valence and different memory systems.

    Directory of Open Access Journals (Sweden)

    Rodrigo S Fernández

    2016-12-01

    Full Text Available Following the presentation of a reminder, consolidated memories become reactivated followed by a process of re-stabilization, which is referred to as reconsolidation. The most common behavioral tool used to reveal this process is interference produced by new learning shortly after memory reactivation. Memory interference is defined as a decrease in memory retrieval, the effect is generated when new information impairs an acquired memory. In general, the target memory and the interference task used are the same. Here we investigated how different memory systems and/or their valence could produce memory reconsolidation interference. We showed that a reactivated neutral declarative memory could be interfered by new learning of a different neutral declarative memory. Then, we revealed that an aversive implicit memory could be interfered by the presentation of a reminder followed by a threatening social event. Finally, we showed that the reconsolidation of a neutral declarative memory is unaffected by the acquisition of an aversive implicit memory and conversely, this memory remains intact when the neutral declarative memory is used as interference. These results suggest that the interference of memory reconsolidation is effective when two task rely on the same memory system or both evoke negative valence.

  20. DSE inspired model for the pion's valence dressed-quark GPD

    CERN Document Server

    Chang, L; Moutarde, H; Roberts, C D; Rodríguez-Quintero, J; Sabatié, F

    2015-01-01

    We sketch here an approach to the computation of generalised parton distributions (GPDs), based upon a rainbow-ladder (RL) truncation of QCD's Dyson-Schwinger equations and exemplified via the pion's valence dressed-quark GPD, $H_\\pi^{\\rm v}(x,\\xi,t)$. Our analysis focuses on the case of zero skewness, $\\xi=0$, and underlines that the impulse-approximation used hitherto to define the pion's valence dressed-quark GPD is generally invalid owing to omission of contributions from the gluons which bind dressed-quarks into the pion. A simple correction enables us to identify a practicable improvement to the approximation for $H_\\pi^{\\rm v}(x,0,t)$, expressed as the Radon transform of a single amplitude. Therewith we obtain results for $H_\\pi^{\\rm v}(x,0,t)$ and the associated impact-parameter dependent distribution, $q_\\pi^{\\rm v}(x,|\\vec{b}_\\perp|)$, which provide a qualitatively sound picture of the pion's dressed-quark structure at an hadronic scale.