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Sample records for 10d effective action

  1. Dimensional reduction of 10d heterotic string effective lagrangian with higher derivative terms

    Dimensional reduction of the 10d Supergravity-Yang-Mills theories containing up to four derivatives is described. Unexpected nondiagonal corrections to 4d gauge kinetic function and negative contributions to scalar potential are found. We analyzed the general structure of the resulting lagrangian and discuss the possible phenomenological consequences. (author)

  2. Effective actions near singularities

    We study the heterotic string compactified on K3x T2 near the line T=U, where the effective action becomes singular due to an SU(2) gauge symmetry enhancement. By 'integrating in' the light W± vector multiplets we derive a quantum corrected effective action which is manifestly SU(2) invariant and non-singular. This effective action is found to be consistent with a residual SL(2,Ζ) quantum symmetry on the line T=U. In an appropriate decompactification limit, we recover the known SU(2) invariant action in five dimensions. (author)

  3. Thermopower, Hall effect and magnetoresistivity of Ru 1- xSb xSr 2Sm 1.5Ce 0.5Cu 2O 10- d

    Ilonca, G.; Patapis, S.; Beiusan, F.; Lung, C.; Toma, V.; Balint, P.; Bodea, M.; Jurcut, T.

    2007-09-01

    Magnetoresistivity, thermopower and Hall effect on the samples of Ru1-xSbxSr2Sm1.5Ce0.5Cu2O10-d were investigated in the temperature range 4-300 K with a magnetic field up to 9 T. Superconducting transition temperature decreases with increases content of Sb, due to a distortion of RuO6 octahedral, which is responsible of the increase in hole localization, reflected by Hall concentration, too. The inhomogeneous granular structure is put in evidence by the intragranular, Tco, and intergranular Tcg, transition temperatures. Hall effect and thermopower anomalous decreases below Tmagnetic can be explained within a simple two-band model by a transition from localized to more itinerant behavior in the RuO2 layer at Tmagnetic.

  4. Effects of Security actions

    Bergman, Ramona; Andersson-Sköld, Yvonne; Nyberg, Lars; Johansson, Magnus

    2010-05-01

    In a project funded by the Swedish Civil Contingencies Agency, the effort and work to reduce different kinds of accidents are being evaluated. The project wants to illuminate the links between actions and outcome, so we can learn from today's performance and in the future select more effective measures and overall deal with accidents more efficiently. The project ESS covers the field of frequent accidents such as sliding accidents at home, in house fires and less common accidents such as chemical and land fill accidents up to even more rare accidents such as natural accidents and hazards. In the ESS project SGI (Swedish geotechnical institute) will evaluate the work and effort concerning various natural hazards limited to landslides, erosion and flooding. The aim is to investigate how municipalities handle, especially prevention, of such natural disasters today. The project includes several aspects such as: • which are the driving forces for risk analysis in a municipality • do one use risk mapping (and what type) in municipal risk analysis • which aspects are most important when selecting preventive measures • in which way do one learn from past accidents • and from previous accidents elsewhere, by for example use existing databases • etc There are many aspects that play a role in a well-functioning safety promotion work. The overall goal is to examine present work and activities, highlight what is well functioning and identify weak points. The aim is to find out where more resources are needed and give suggestions for a more efficient security work. This includes identification of the most efficient "tools" in use or needed. Such tools can be education, directives, funding, more easily available maps and information regarding previous accidents and preventive measures etc. The project will result in recommendations for more effective ways to deal with landslides, erosion and flooding. Since different kinds of problems can occur depending on level of

  5. Wilsonian Effective Action of Superstring Theory

    Sen, Ashoke

    2016-01-01

    By integrating out the heavy fields in type II or heterotic string field theory one can construct the effective action for the light fields. This effective theory inherits all the algebraic structures of the parent theory and the effective action automatically satisfies the Batalin-Vilkovisky quantum master equation. This theory is manifestly ultraviolet finite, has only light fields as its explicit degrees of freedom, and the Feynman diagrams of this theory reproduce the exact scattering amplitudes of light states in string theory to any arbitrary order in perturbation theory. Furthermore in this theory the degrees of freedom of light fields above certain energy scale are also implicitly integrated out. This energy scale is determined by a particular parameter labelling a family of equivalent actions, and can be made arbitrarily low, leading to the interpretation of the effective action as the Wilsonian effective action.

  6. Separate and combined effects of a 10-d exposure to hypoxia and inactivity on oxidative function in vivo and mitochondrial respiration ex vivo in humans.

    Salvadego, Desy; Keramidas, Michail E; Brocca, Lorenza; Domenis, Rossana; Mavelli, Irene; Rittweger, Jörn; Eiken, Ola; Mekjavic, Igor B; Grassi, Bruno

    2016-07-01

    An integrative evaluation of oxidative metabolism was carried out in 9 healthy young men (age, 24.1 ± 1.7 yr mean ± SD) before (CTRL) and after a 10-day horizontal bed rest carried out in normoxia (N-BR) or hypoxia (H-BR, FiO2 = 0.147). H-BR was designed to simulate planetary habitats. Pulmonary O2 uptake (V̇o2) and vastus lateralis fractional O2 extraction (changes in deoxygenated hemoglobin+myoglobin concentration, Δ[deoxy(Hb+Mb)] evaluated using near-infrared spectroscopy) were evaluated in normoxia and during an incremental cycle ergometer (CE) and one-leg knee extension (KE) exercise (aimed at reducing cardiovascular constraints to oxidative function). Mitochondrial respiration was evaluated ex vivo by high-resolution respirometry in permeabilized vastus lateralis fibers. During CE V̇o2peak and Δ[deoxy(Hb+Mb)]peak were lower (P work rate exercise was greater in N-BR and H-BR than CTRL, whereas during KE a significant difference vs. CTRL was observed only after N-BR. Maximal mitochondrial respiration determined ex vivo was not affected by either intervention. In N-BR, a significant impairment of oxidative metabolism occurred downstream of central cardiovascular O2 delivery and upstream of mitochondrial function, possibly at the level of the intramuscular matching between O2 supply and utilization and peripheral O2 diffusion. Superposition of hypoxia on bed rest did not aggravate, and partially reversed, the impairment of muscle oxidative function in vivo induced by bed rest. The effects of longer exposures will have to be determined. PMID:27197861

  7. On String Field Theory and Effective Actions

    Giveon, Amit

    1992-01-01

    A truncation of string field theory is compared with the duality invariant effective action of $D=4, N=4$ heterotic strings to cubic order. The three string vertex must satisfy a set of compatibility conditions. Any cyclic three string vertex is compatible with the $D=4, N=4$ effective field theory. The effective actions may be useful in understanding the non--polynomial structure and the underlying symmetry of covariant closed string field theory, and in addressing issues of background indep...

  8. Action-based effects on music perception

    Pieter-Jan eMaes

    2014-01-01

    Full Text Available The classical, disembodied approach to music cognition conceptualizes action and perception as separate, peripheral phenomena. In contrast, embodied accounts to music cognition emphasize the central role of the close coupling of action and perception. It is a commonly established fact that perception spurs action tendencies. We present a theoretical framework capturing the ways that the human motor system, and the actions it produces, can reciprocally influence the perception of music. The cornerstone of this framework is the common coding theory postulating a representational overlap in the brain between the planning, the execution, and the perception of movement. The integration of action and perception in so-called internal models is explained as a result of associative learning processes. Characteristic of internal models is that they allow intended or perceived sensory states to be transferred into corresponding motor commands (inverse modelling, and vice versa, to predict the sensory outcomes of planned actions (forward modelling. Embodied accounts typically adhere to inverse modelling to explain action effects on music perception (Leman, 2007. We extent this account by pinpointing forward modelling as an alternative mechanism by which action can modulate perception. We provide an extensive overview of recent empirical evidence in support of this idea. Additionally, we demonstrate that motor dysfunctions can cause perceptual disabilities, supporting the main idea of the paper that the human motor system plays a functional role in auditory perception. The finding that music perception is shaped by the human motor system, and the action it produces, suggests that the musical mind is highly embodied. However, we advocate for a more radical approach to embodied (music cognition in the sense that it needs to be considered as a dynamic process, in which aspects of action, perception, introspection, and social interaction are of crucial

  9. Action-based effects on music perception.

    Maes, Pieter-Jan; Leman, Marc; Palmer, Caroline; Wanderley, Marcelo M

    2014-01-01

    The classical, disembodied approach to music cognition conceptualizes action and perception as separate, peripheral processes. In contrast, embodied accounts of music cognition emphasize the central role of the close coupling of action and perception. It is a commonly established fact that perception spurs action tendencies. We present a theoretical framework that captures the ways in which the human motor system and its actions can reciprocally influence the perception of music. The cornerstone of this framework is the common coding theory, postulating a representational overlap in the brain between the planning, the execution, and the perception of movement. The integration of action and perception in so-called internal models is explained as a result of associative learning processes. Characteristic of internal models is that they allow intended or perceived sensory states to be transferred into corresponding motor commands (inverse modeling), and vice versa, to predict the sensory outcomes of planned actions (forward modeling). Embodied accounts typically refer to inverse modeling to explain action effects on music perception (Leman, 2007). We extend this account by pinpointing forward modeling as an alternative mechanism by which action can modulate perception. We provide an extensive overview of recent empirical evidence in support of this idea. Additionally, we demonstrate that motor dysfunctions can cause perceptual disabilities, supporting the main idea of the paper that the human motor system plays a functional role in auditory perception. The finding that music perception is shaped by the human motor system and its actions suggests that the musical mind is highly embodied. However, we advocate for a more radical approach to embodied (music) cognition in the sense that it needs to be considered as a dynamical process, in which aspects of action, perception, introspection, and social interaction are of crucial importance. PMID:24454299

  10. Action-effect bindings and ideomotor learning in intention- and stimulus-based actions

    ArvidHerwig

    2012-10-01

    Full Text Available According to ideomotor theory, action-effect associations are crucial for voluntary action control. Recently, a number of studies started to investigate the conditions that mediate the acquisition and application of action-effect associations by comparing actions carried out in response to exogenous stimuli (stimulus-based with actions selected endogenously (intention-based. There is evidence that the acquisition and/or application of action-effect associations is boosted when acting in an intention-based action mode. For instance, bidirectional action-effect associations were diagnosed in a forced choice test phase if participants previously experienced action-effect couplings in an intention-based but not in a stimulus-based action mode. The present study aims at investigating effects of the action mode on action-effect associations in more detail. In a series of experiments, we compared the strength and durability of short-term action-effect associations (binding immediately following intention- as well as stimulus-based actions. Moreover, long-term action-effect associations (learning were assessed in a subsequent test phase. Our results show short-term action-effect associations of equal strength and durability for both action modes. However, replicating previous results, long-term associations were observed only following intention-based actions. These findings indicate that the effect of the action mode on long-term associations cannot merely be a result of accumulated short-term action-effect bindings. Instead, only those episodic bindings are selectively perpetuated or retrieved that integrate action-relevant aspects of the processing event, i.e., in case of intention-based actions, the link between action and ensuing effect.

  11. Effective actions for anomalous hydrodynamics

    We argue that an effective field theory of local fluid elements captures the constraints on hydrodynamic transport stemming from the presence of quantum anomalies in the underlying microscopic theory. Focussing on global current anomalies for an arbitrary flavour group, we derive the anomalous constitutive relations in arbitrary even dimensions. We demonstrate that our results agree with the constraints on anomaly governed transport derived hitherto using a local version of the second law of thermodynamics. The construction crucially uses the anomaly inflow mechanism and involves a novel thermofield double construction. In particular, we show that the anomalous Ward identities necessitate non-trivial interaction between the two parts of the Schwinger-Keldysh contour

  12. (-)-Carvone: antispasmodic effect and mode of action.

    Souza, Fábia Valéria M; da Rocha, Marcelly Barbosa; de Souza, Damião P; Marçal, Rosilene Moretti

    2013-03-01

    (-)-Carvone is a monoterpene ketone found in spearmint (Mentha spicata var. crispa) essential oil that is widely used as an odor and flavor additive. An intestinal antispasmodic effect was recently reported for (-)-carvone, and it has been shown to be more potent than its (+)-antipode. The mechanism of (-)-carvone action in the intestines has not been investigated. To gain a better understanding of the (-)-carvone antispasmodic effect, we investigated its pharmacological effects in the guinea pig ileum. Terminal portions of the ileum were mounted for isotonic contraction recordings. The effect of (-)-carvone was compared with that of the classical calcium channel blocker (CCB) verapamil. In isolated ileal smooth muscle, (-)-carvone did not produce direct contractile or relaxation responses and did not modify electrically elicited contractions or low K(+)-evoked contractions. The submaximal contractions induced by histamine (p<0.001), BaCl2 (p<0.05), and carbachol (p<0.01) were significantly reduced by (-)-carvone. The contractile response elicited by high concentrations of carbachol was reduced but not abolished by (-)-carvone. No additive action was detected with co-incubation of (-)-carvone and verapamil on carbachol-induced contraction. (-)-Carvone reduced the contraction induced by high K(+) and was almost 100 times more potent than verapamil. Thus, (-)-carvone showed a typical and potent CCB-like action. Many effects described for both (-)-carvone and spearmint oil can be explained as a CCB-like mode of action. PMID:23103297

  13. Effective boundary action in fermion string theory

    Continual Polyakov integral for the Neveu-Schwarz-Ramon (NSR) type fermion string is calculated on the Riemann Surface with special choice of local boundary conditions for the fermion fields. The derived expressions are used when studying behaviour of the string Green function in configurational space. Generalization of the effective fermion action for the case of non-Archimedean strings is discussed. 11 refs

  14. Low energy effective actions with composite fields

    We investigate a Wilson real space renormalization gorup approach for theories in which composite fields are needed at low energies. It furnishes a sequence of effective actions SΛ which depend on an UV cut-off Λ. We adopt Wilsons fundamental postulate that these effective actions should be local. This is our basic guiding principle on how to construct ''blockspins'', i.e. the fields which appear in the effective actions. Given a fundamental high energy theory which does not contain composite fields we gradually integrate out high frequency modes in order to lower the cut-off Λ. Eventually appearing nonlocalities at some cut-off value Λc indicate the necessity to introduce new composite degrees of freedom into the theory. An analysis based on Symanzik's infinite set of Bethe-Salpeter equations for all n-point functions shows that a local low energy effective action containing composite fields can be constructed at the compositeness scale Λc. Further integration of high frequency modes generates new nonlocalities which can be absorbed into the composite degrees of freedom. There are indications from an 1/N expansion that this suffices already to eliminate high energy degrees of freedom from the composite field so that no separate integration is needed to achieve this. In general the composite field will have self interactions. (orig.)

  15. Holographic effective actions from black holes

    Using the Wald's relation between the Noether charge of diffeomorphisms and the entropy for a generic spacetime possessing a bifurcation surface, we introduce a method to obtain a family of higher order derivatives effective actions from the entropy of black holes. We consider the entropy as the starting point and we analyze the procedure of derivation of the action functional. We specialize to a particular class of theories which simplifies the calculations, f(R) theories. We apply the procedure to loop quantum gravity and to a general class of log-corrected entropy formulas.

  16. Symmetry-improved CJT effective action

    The formalism introduced by Cornwall, Jackiw and Tomboulis (CJT) provides a systematic approach to consistently resumming non-perturbative effects in Quantum Thermal Field Theory. One major limitation of the CJT effective action is that its loopwise expansion introduces residual violations of possible global symmetries, thus giving rise to massive Goldstone bosons in the spontaneously broken phase of the theory. In this paper we develop a novel symmetry-improved CJT formalism for consistently encoding global symmetries in a loopwise expansion. In our formalism, the extremal solutions of the fields and propagators to a loopwise truncated CJT effective action are subject to additional constraints given by the Ward Identities due to global symmetries. By considering a simple O(2) scalar model, we show that, unlike other methods, our approach satisfies a number of important field-theoretic properties. In particular, we find that the Goldstone boson resulting from spontaneous symmetry breaking of O(2) is massless and the phase transition is a second-order one, already in the Hartree–Fock approximation. After taking the sunset diagrams into account, we show how our approach properly describes the threshold properties of the massless Goldstone boson and the Higgs particle in the loops. Finally, assuming minimal modifications to the Hartree–Fock approximated CJT effective action, we calculate the corresponding symmetry-improved CJT effective potential and discuss the conditions for its uniqueness for scalar-field values away from its minimum

  17. Cosmic fluctuations from quantum effective action

    Wetterich, C

    2015-01-01

    Does the observable spectrum of cosmic fluctuations depend on detailed initial conditions? This addresses the question if the general inflationary paradigm is sufficient to predict within a given model the spectrum and amplitude of cosmic fluctuations, or if additional particular assumptions about the initial conditions are needed. The answer depends on the number of e-foldings $N_{in}$ between the beginning of inflation and horizon crossing of the observable fluctuations. We discuss an interacting inflaton field in an arbitrary homogeneous and isotropic geometry, employing the quantum effective action $\\Gamma$. An exact time evolution equation for the correlation function involves the second functional derivative $\\Gamma^{(2)}$. The operator formalism and quantum vacua for interacting fields are not needed. Use of the effective action also allows one to address the change of frames by field transformations (field relativity). For not too large $N_{in}$ we find that memory of the initial conditions is preserv...

  18. Effectively Discriminating Fighting Shots in Action Movies

    Shu-Gao Ma; Wei-Qiang Wang

    2011-01-01

    Fighting shots are the highlights of action movies and an effective approach to discriminating fighting shots is very useful for many applications, such as movie trailer construction, movie content filtering, and movie content retrieval. In this paper, we present a novel method for this task. Our approach first extracts the reliable motion information of local invariant features through a robust keypoint tracking computation; then foreground keypoints are distinguished from background keypoints by a sophisticated voting process; further, the parameters of the camera motion model is computed based on the motion information of background keypoints, and this model is then used as a reference to compute the actual motion of foreground keypoints; finally, the corresponding feature vectors are extracted to characterizing the motions of foreground keypoints, and a support vector machine (SVM) classifier is trained based on the extracted feature vectors to discriminate fighting shots. Experimental results on representative action movies show our approach is very effective.

  19. Effective action in general chiral superfield model

    Petrov, A. Yu.

    2000-01-01

    The effective action in general chiral superfield model with arbitrary k\\"{a}hlerian potential $K(\\bar{\\Phi},\\Phi)$ and chiral (holomorphic) potential $W(\\Phi)$ is considered. The one-loop and two-loop contributions to k\\"{a}hlerian effective potential and two-loop (first non-zero) contribution to chiral effective potential are found for arbitrary form of functions $K(\\bar{\\Phi},\\Phi)$ and $W(\\Phi)$. It is found that despite the theory is non-renormalizable in general case two-loop contributi...

  20. Instant Attraction: Immediate Action-Effect Bindings Occur for Both, Stimulus- and Goal-Driven Actions

    Janczyk, Markus; Heinemann, Alexander; Pfister, Roland

    2012-01-01

    Flexible behavior is only possible if contingencies between own actions and following environmental effects are acquired as quickly as possible; and recent findings indeed point toward an immediate formation of action-effect bindings already after a single coupling of an action and its effect. The present study explored whether these short-term bindings occur for both, stimulus- and goal-driven actions (“forced-choice actions” vs. “free-choice actions”). Two experiments confirmed that immedia...

  1. Instant attraction: Immediate action-effect bindings occur for both, stimulus- and goal-driven actions

    MarkusJanczyk

    2012-10-01

    Full Text Available Flexible behavior is only possible if contingencies between own actions and following environmental effects are acquired as quickly as possible; and recent findings indeed point toward an immediate formation of action-effect bindings already after a single coupling of an action and its effect. The present study explored whether these short-term bindings occur for both, stimulus- and goal-driven actions (“forced-choice actions” vs. “free-choice actions”. Two experiments confirmed that immediate action-effect bindings are formed for both types of actions and affect upcoming behavior. These findings support the view that action-effect binding is a ubiquitous phenomenon which occurs for any type of action.

  2. Effective action approach to quantum chromodynamics

    Though the Lagrangian of quantum chromodynamics is well known, it has proven extremely difficult to derive precisely all its consequences to compare with experiment. Approximations based on physical reasoning must be made. One method is to calculate the effective action for some particularly simple configuration of gluons and use this to analyze an arbitrary system of interacting quarks. In the first chapter, the one-loop correction to the gluon propagator is computed in two different ways - dimensional regularization and Schwinger's proper time method. The renormalization mass parameters appearing in the two treatments can then be related and the exact one-loop effective action of a constant gluon field can be expressed in terms of the experimentally determinable Λ/sub MS/. In the following chapter, the interaction of a heavy quark-antiquark pair governed by this action is considered and it is shown how the spectrum, and, in particular, the spin splittings of the bound states can be found. Due to asymptotic freedom, a massive quarkonium is analogous to a non-relativistic electromagnetic system. At short distances, the results are the same as those derived from perturbation theory though, for example, the hyperfine structure arises in a different way. At large distances, the analysis is qualitative but our results agree with the predictions of strong coupling lattice gauge theories

  3. Effective actions for relativistic fluids from holography

    de Boer, Jan; Pinzani-Fokeeva, Natalia

    2015-01-01

    Motivated by recent progress in developing action formulations of relativistic hydrodynamics, we use holography to derive the low energy dissipationless effective action for strongly coupled conformal fluids. Our analysis is based on the study of novel double Dirichlet problems for the gravitational field, in which the boundary conditions are set on two codimension one timelike hypersurfaces (branes). We provide a geometric interpretation of the Goldstone bosons appearing in such constructions in terms of a family of spatial geodesics extending between the ultraviolet and the infrared brane. Furthermore, we discuss supplementing double Dirichlet problems with information about the near-horizon geometry. We show that upon coupling to a membrane paradigm boundary condition, our approach reproduces correctly the complex dispersion relation for both sound and shear waves. We also demonstrate that upon a Wick rotation, our formulation reproduces the equilibrium partition function formalism, provided the near-horiz...

  4. From action intentions to action effects: how does the sense of agency come about?

    Valérian Chambon; Nura Sidarus

    2014-01-01

    Sense of agency refers to the feeling of controlling an external event through one’s own action. On one influential view, agency depends on how predictable the consequences of one’s action are, getting stronger as the match between predicted and actual effect of an action gets closer. Thus, sense of agency arises when external events that follow our action are consistent with predictions of action effects made by the motor system while we perform or simply intend to perform an action. Accordi...

  5. Cosmic fluctuations from a quantum effective action

    Wetterich, C.

    2015-10-01

    Does the observable spectrum of cosmic fluctuations depend on detailed initial conditions? This addresses the question if the general inflationary paradigm is sufficient to predict within a given model the spectrum and amplitude of cosmic fluctuations, or if additional particular assumptions about the initial conditions are needed. The answer depends on the number of e -foldings Nin between the beginning of inflation and horizon crossing of the observable fluctuations. We discuss an interacting inflaton field in an arbitrary homogeneous and isotropic geometry, employing the quantum effective action Γ . An exact time evolution equation for the correlation function involves the second functional derivative Γ(2 ) . The operator formalism and quantum vacua for interacting fields are not needed. Use of the effective action also allows one to address the change of frames by field transformations (field relativity). Within the approximation of a derivative expansion for the effective action we find the most general solution for the correlation function, including mixed quantum states. For not too large Nin the memory of the initial conditions is preserved. In this case the cosmic microwave background cannot disentangle between the initial spectrum and its processing at horizon crossing. The inflaton potential cannot be reconstructed without assumptions about the initial state of the universe. We argue that for very large Nin a universal scaling form of the correlation function is reached for the range of observable modes. This can be due to symmetrization and equilibration effects, not yet contained in our approximation, which drive the short distance tail of the correlation function toward the Lorentz invariant propagator in flat space.

  6. Effective action of domain wall networks

    U(NC) gauge theory with NF fundamental scalars admits BPS junctions of domain walls. When the networks/webs of these walls contain loops, their size moduli give localized massless modes. We construct Kaehler potential of their effective action. In the large size limit Kaehler metric is well approximated by kinetic energy of walls and junctions, which is understood in terms of tropical geometry. Kaehler potential can be expressed in terms of hypergeometric functions that are useful to understand small size behavior. Even when the loop shrinks, the metric is regular with positive curvature. Moduli space of a single triangle loop has a geometry between a cone and a cigar

  7. Effective actions for statistical data assimilation

    Data assimilation is a problem in estimating the fixed parameters and state of a model of an observed dynamical system as it receives inputs from measurements passing information to the model. Using methods developed in statistical physics, we present effective actions and equations of motion for the mean orbits associated with the temporal development of a dynamical model when it has errors, there is uncertainty in its initial state, and it receives information from noisy measurements. If there are statistical dependences among errors in the measurements they can be included in this approach.

  8. Effective action calculation in lattice QCD

    A method (called the effective action method) devised to make analytic calculations in Quantum Chromodynamics in the region of strong coupling is presented. First, the author deals with developing the calculation of a strong coupling expansion of the generating functional for gauge systems on a lattice with arbitrary sources. An accompanying manual describes the implementation of this calculation on a computer. The next step consists of substituting the expressions for the one-link free energies for a specific gauge group in the result of the previous calculation. This process of substitution, together with the replacement of the sources by a bilinear combination of fermion fields, is described for the group SU(3). More details on the implementation of the substitution scheme on a computer can be found in the accompanying manual. From the effective action thus obtained in terms of meson fields and baryon fields the Green functions of the theory can be derived. As an illustrative application the effective potential determining the vacuum expectation value of the meson field is calculated. (Auth.)

  9. Exploring soft constraints on effective actions

    Bianchi, Massimo; Huang, Yu-tin; Lee, Chao-Jung; Wen, Congkao

    2016-01-01

    We study effective actions for simultaneous breaking of space-time and internal symmetries. Novel features arise due to the mixing of Goldstone modes under the broken symmetries which, in contrast to the usual Adler's zero, leads to non-vanishing soft limits. Such scenarios are common for spontaneously broken SCFT's. We explicitly test these soft theorems for $\\mathcal{N}=4$ sYM in the Coulomb branch both perturbatively and non-perturbatively. We explore the soft constraints systematically utilizing recursion relations. In the pure dilaton sector of a general CFT, we show that all amplitudes up to order $s^{n} \\sim \\partial^{2n}$ are completely determined in terms of the $k$-point amplitudes at order $s^k$ with $k \\leq n$. Terms with at most one derivative acting on each dilaton insertion are completely fixed and coincide with those appearing in the conformal DBI, i.e. DBI in AdS. With maximal supersymmetry, the effective actions are further constrained, leading to new non-renormalization theorems. In particu...

  10. The effective action for composite Higgs particles

    There is reason to believe that massive composite (fermion-antifermion) scalar particles closely resembling the usual fundamental scalar Higgs fields exist in theories with dynamically broken gauge symmetries. This composite Higgs couples directly to the fermions in proportion to their symmetry-violating self-energies. Induced couplings to the gauge bosons and self-couplings are claculated as loop effects. This involves deriving the effective action in terms of the full propagators and background fields. The couplings between the composite Higgs and the gauge bosons are the same as those in models with fundamental scalars. The self-couplings are determined and fix all parameters associated with the composite scalars. Comments regarding extending work to higher orders and concerning the symmetry-violating solutions to the fermion Schwinger-Dyson equation are given in this paper

  11. The Universal One-Loop Effective Action

    Drozd, Aleksandra; Quevillon, Jérémie; You, Tevong

    2016-01-01

    We present the universal one-loop effective action for all operators of dimension up to six obtained by integrating out massive, non-degenerate multiplets. Our general expression may be applied to loops of heavy fermions or bosons, and has been checked against partial results available in the literature. The broad applicability of this approach simplifies one-loop matching from an ultraviolet model to a lower-energy effective field theory (EFT), a procedure which is now reduced to the evaluation of a combination of matrices in our universal expression, without any loop integrals to evaluate. We illustrate the relationship of our results to the Standard Model (SM) EFT, using as an example the supersymmetric stop and sbottom squark Lagrangian and extracting from our universal expression the Wilson coefficients of dimension-six operators composed of SM fields.

  12. The universal one-loop effective action

    Drozd, Aleksandra; Ellis, John; Quevillon, Jérémie; You, Tevong

    2016-03-01

    We present the universal one-loop effective action for all operators of dimension up to six obtained by integrating out massive, non-degenerate multiplets. Our general expression may be applied to loops of heavy fermions or bosons, and has been checked against partial results available in the literature. The broad applicability of this approach simplifies one-loop matching from an ultraviolet model to a lower-energy effective field theory (EFT), a procedure which is now reduced to the evaluation of a combination of matrices in our universal expression, without any loop integrals to evaluate. We illustrate the relationship of our results to the Standard Model (SM) EFT, using as an example the supersymmetric stop and sbottom squark Lagrangian and extracting from our universal expression the Wilson coefficients of dimension-six operators composed of SM fields.

  13. Action-based effects on music perception

    Maes, Pieter-Jan; Leman, Marc; Palmer, Caroline; Wanderley, Marcelo M.

    2014-01-01

    The classical, disembodied approach to music cognition conceptualizes action and perception as separate, peripheral processes. In contrast, embodied accounts of music cognition emphasize the central role of the close coupling of action and perception. It is a commonly established fact that perception spurs action tendencies. We present a theoretical framework that captures the ways in which the human motor system and its actions can reciprocally influence the perception of music. The cornerst...

  14. Action-based effects on music perception

    Pieter-Jan eMaes; Marc eLeman; Caroline ePalmer; Marcelo eWanderley

    2014-01-01

    The classical, disembodied approach to music cognition conceptualizes action and perception as separate, peripheral phenomena. In contrast, embodied accounts to music cognition emphasize the central role of the close coupling of action and perception. It is a commonly established fact that perception spurs action tendencies. We present a theoretical framework capturing the ways that the human motor system, and the actions it produces, can reciprocally influence the perception of music. The co...

  15. Effective Action of Domain Wall Networks

    Eto, M; Nagashima, T; Nitta, M; Ohashi, K; Sakai, N; Eto, Minoru; Fujimori, Toshiaki; Nagashima, Takayuki; Nitta, Muneto; Ohashi, Keisuke; Sakai, Norisuke

    2007-01-01

    U(Nc) gauge theory with Nf fundamental scalars admits BPS junctions of domain walls. When the networks/webs of these walls contain loops, their size moduli give localized massless modes. We construct K\\"ahler potential of their effective action. In the large size limit K\\"ahler metric is well approximated by kinetic energy of walls and junctions, which is understood in terms of tropical geometry. K\\"ahler potential can be expressed in terms of hypergeometric functions which are useful to understand small size behavior. Even when the loop shrinks, the metric is regular with positive curvature. Moduli space of a single triangle loop has a geometry between a cone and a cigar.

  16. Boundary Effective Action for Quantum Hall States

    Gromov, Andrey; Jensen, Kristan; Abanov, Alexander G.

    2016-03-01

    We consider quantum Hall states on a space with boundary, focusing on the aspects of the edge physics which are completely determined by the symmetries of the problem. There are four distinct terms of Chern-Simons type that appear in the low-energy effective action of the state. Two of these protect gapless edge modes. They describe Hall conductance and, with some provisions, thermal Hall conductance. The remaining two, including the Wen-Zee term, which contributes to the Hall viscosity, do not protect gapless edge modes but are instead related to the local boundary response fixed by symmetries. We highlight some basic features of this response. It follows that the coefficient of the Wen-Zee term can change across an interface without closing a gap or breaking a symmetry.

  17. Perception of actions performed by external agents presupposes knowledge about the relationship between action and effect.

    Raos, Vassilis; Savaki, Helen E

    2016-05-15

    We used the (14)C-deoxyglucose method to reveal changes in activity, in the lateral sulcus of monkeys, elicited by reaching-to-grasp in the light or in the dark and by observation of the same action executed by an external agent. Both visually-guided execution and observation of the same action activated the secondary somatosensory cortex, the ventral somatosensory area, the somatorecipient parietal ventral area, the retroinsula and the caudo-medial area of the auditory belt. These matching activations indicate that the somesthetic consequences of movements, generated bottom-up during action execution, may also be triggered top-down during action observation to represent the predicted sensory consequences of the perceived movement. The posterior granular part of insula found to be activated only for action execution and its anterior agranular part activated only for action observation may contribute to the attribution of action to the correct agent. Also, execution in the dark implicated all components activated by execution in the light but the retroinsula. In conclusion, activation of the somatorecipient parietal areas, not only for action-execution but also for action-observation, indicates that perception of actions performed by an external agent presupposes knowledge about the action-effect relationships, and that understanding others' actions consists of running off-line previously stored sensory-motor programs. PMID:26892857

  18. Motor imagery during action observation modulates automatic imitation effects in rhythmical actions

    Daniel Lloyd Eaves

    2014-02-01

    Full Text Available We have previously shown that passively observing a task-irrelevant rhythmical action can bias the cycle time of a subsequently executed rhythmical action. Here we use the same paradigm to investigate the impact of different forms of motor imagery (MI during action observation (AO on this automatic imitation (AI effect. Participants saw a picture of the instructed action followed by a rhythmical distractor movie, wherein cycle time was subtly manipulated across trials. They then executed the instructed rhythmical action. When participants imagined performing the instructed action in synchrony with the distractor action (AO + MI, a strong imitation bias was found that was significantly greater than in our previous study. The bias was pronounced equally for compatible and incompatible trials, wherein observed and imagined actions were different in type (e.g., face washing vs. painting or plane of movement, or both. In contrast, no imitation bias was observed when MI conflicted with AO. In Experiment 2, motor execution synchronised with AO produced a stronger imitation bias compared to AO + MI, showing an advantage in synchronisation for overt execution over MI. Furthermore, the bias was stronger when participants synchronised the instructed action with the distractor movie, compared to when they synchronised the distractor action with the distractor movie. Although we still observed a significant bias in the latter condition, this finding indicates a degree of specificity in AI effects for the identity of the synchronised action. Overall, our data show that MI can substantially modulate the effects of AO on subsequent execution, wherein: (1 combined AO + MI can enhance AI effects relative to passive AO; (2 observed and imagined actions can be flexibly coordinated across different action types and planes; and (3 conflicting AO + MI can abolish AI effects. Therefore, combined AO + MI instructions should be considered in motor training and

  19. The role of action effects in 12-month-olds' action control: a comparison of televised model and live model.

    Klein, Annette M; Hauf, Petra; Aschersleben, Gisa

    2006-12-01

    The present study investigated differences in infant imitation after watching a televised model and a live model and addressed the issue of whether action effects influence infants' action control in both cases. In a 2x2 design, 12-month-old infants observed a live or a televised model performing a three-step action sequence, in which either the 2nd or the 3rd action step was combined with an acoustical action effect. We assumed that infants would use the observed action-effect relations for their own action control in the test phase afterwards. Even though results exhibited differences in the absolute amount of imitation between the two demonstration groups, both groups showed similar result patterns regarding the action effect manipulation: infants imitated the action step that was followed by a salient action effect more often and mostly as the first target action, emphasizing the important role of action effects in infants' action control. PMID:17138306

  20. The effective action in four-dimensional CDT

    Gizbert-Studnicki, Jakub

    2015-01-01

    We present recent results concerning the measurement and analysis of the effective action in four-dimensional Causal Dynamical Triangulations. The action describes quantum fluctuations of the spatial volume of the CDT universe (or alternatively the scale factor) after integrating out other degrees of freedom. We use the covariance of volume fluctuations to measure and parametrize the effective action inside the de Sitter phase, also called the C phase. We show that the action is consistent with a simple discretization of the minisuperspace action (with a reversed overall sign). We discuss possible subleading corrections and show how to construct a more complicated effective action comprising both integer and half-integer discrete proper time layers. We introduce a new method of the effective action measurement based on the transfer matrix. We show that the results of the new method are fully consistent with the covariance matrix method inside the de Sitter phase. We use the new method to measure the effective...

  1. Faddeev-Niemi Conjecture and Effective Action of QCD

    Cho, Y. M.; Lee, H. W.; Pak, D. G.

    2001-01-01

    We calculate a one loop effective action of SU(2) QCD in the presence of the monopole background, and find a possible connection between the resulting QCD effective action and a generalized Skyrme-Faddeev action of the non-linear sigma model. The result is obtained using the gauge-independent decomposotion of the gauge potential into the topological degrees which describes the non-Abelian monopoles and the local dynamical degrees of the potential, and integrating out all the dynamical degrees...

  2. Effective action for supersymmetrical chiral anomaly

    It is proved that the consistency conditions of the type of Wess-Zumino conditions are necessary and sufficient for local integrability of supersymmetrical chiral anomaly. The global integrability condition implies discreteness of the coefficient in anomalous action. Explicit formulas for consistent anomalies and corresponding functional depending on superfields of various types are obtained

  3. Conformally covariant operators and effective action in external gravitational field

    The n-dimensional expressions for the second order conformally covariant differentional operators acting on vector and tensor fields and for the fourth order conformally covariant operator acting on scalar fields are obtained. For the fourth order operator one-loop effective action is evaluated in four dimensions. The possibility of effective action evaluation for other conformally covariant operators is discussed

  4. Energy Transfer between Throats from a 10d Perspective

    Harling, B v; Noguchi, T

    2007-01-01

    Strongly warped regions, also known as throats, are a common feature of the type IIB string theory landscape. If one of the throats is heated during cosmological evolution, the energy is subsequently transferred to other throats or to massless fields in the unwarped bulk of the Calabi-Yau orientifold. This energy transfer proceeds either by Hawking radiation from the black hole horizon in the heated throat or, at later times, by the decay of throat-localized Kaluza-Klein states. In both cases, we calculate in a 10d setup the energy transfer rate (respectively decay rate) as a function of the AdS scales of the throats and of their relative distance. Compared to existing results based on 5d models, we find a significant suppression of the energy transfer rates if the size of the embedding Calabi-Yau orientifold is much larger than the AdS radii of the throats. This effect can be partially compensated by a small distance between the throats. These results are relevant, e.g., for the analysis of reheating after b...

  5. Energy transfer between throats from a 10D perspective

    Strongly warped regions, also known as throats, are a common feature of the type IIB string theory landscape. If one of the throats is heated during cosmological evolution, the energy is subsequently transferred to other throats or to massless fields in the unwarped bulk of the Calabi-Yau orientifold. This energy transfer proceeds either by Hawking radiation from the black hole horizon in the heated throat or, at later times, by the decay of throat-localized Kaluza-Klein states. In both cases, we calculate in a 10d setup the energy transfer rate (respectively decay rate) as a function of the AdS scales of the throats and of their relative distance. Compared to existing results based on 5d models, we find a significant suppression of the energy transfer rates if the size of the embedding Calabi-Yau orientifold is much larger than the AdS radii of the throats. This effect can be partially compensated by a small distance between the throats. These results are relevant, e.g., for the analysis of reheating after brane inflation. Our calculation employs the dual gauge theory picture in which each throat is described by a strongly coupled 4d gauge theory, the degrees of freedom of which are localized at a certain position in the compact space

  6. On the influence of reward on action-effect binding

    PaulSimonMuhle-Karbe

    2012-11-01

    Full Text Available Ideomotor theory states that the formation of anticipatory representations about the perceptual consequences of an action (i.e. action-effect (A-E binding provides the functional basis of voluntary action control. A host of studies has demonstrated that A-E binding occurs fast and effortlessly, yet only little is known about cognitive and affective factors that influence this learning process. In the present study, we sought to test whether the motivational value of an action modulates the acquisition of A-E associations. To this end, we associated specific actions with monetary incentives during the acquisition of novel A-E mappings. In a subsequent test phase, the degree of binding was assessed by presenting the former effect stimuli as task-irrelevant response primes in a forced-choice response task in the absence of any reward. Binding, as indexed by response priming through the former action effects, was only found for reward-related A-E mappings. Moreover, the degree to which reward associations modulated the binding strength was predicted by individuals’ trait sensitivity to reward. These observations indicate that the association of actions and their immediate outcomes depends on the motivational value of the action during learning, as well as on the motivational disposition of the individual. On a larger scale, these findings also highlight the link between ideomotor theories and reinforcement-learning theories, providing an interesting perspective for future research on anticipatory regulation of behavior.

  7. Effective average action for gauge theories and exact evolution equations

    We propose a new nonperturbative evolution equation for Yang-Mills theories. It describes the scale dependence of an effective action. The running of the nonabelian gauge coupling in arbitrary dimension is computed. (orig.)

  8. World-volume Effective Actions of Exotic Five-branes

    Kimura, Tetsuji; Yata, Masaya

    2014-01-01

    We construct world-volume effective actions of exotic $5^2_2$-branes in type IIA and IIB string theories. The effective actions are given in fully space-time covariant forms with two Killing vectors associated with background isometries. The effective theories are governed by the six-dimensional $\\mathcal{N}=(2,0)$ tensor multiplet and $\\mathcal{N}=(1,1)$ vector multiplet, respectively. Performing the S-duality transformation to the $5^2_2$-brane effective action in type IIB string theory, we also work out the world-volume action of the $5^2_3$-brane. We discuss some additional issues relevant to the exotic five-branes in type I and heterotic string theories.

  9. Holographic RG flow and the quantum effective action

    The calculation of the full (renormalized) holographic action is undertaken in general Einstein-scalar theories. The appropriate formalism is developed and the renormalized effective action is calculated up to two derivatives in the metric and scalar operators. The holographic RG equations involve a generalized Ricci flow for the space-time metric as well as the standard β-function flow for scalar operators. Several examples are analyzed and the effective action is calculated. A set of conserved quantities of the holographic flow is found, whose interpretation is not yet understood. (Copyright copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Arsenic: health effects, mechanisms of actions, and research issues.

    Abernathy, C O; Liu, Y. P.; Longfellow, D; Aposhian, H V; Beck, B.; Fowler, B.; Goyer, R; Menzer, R.; Rossman, T; Thompson, C.; Waalkes, M

    1999-01-01

    A meeting on the health effects of arsenic (As), its modes of action, and areas in need of future research was held in Hunt Valley, Maryland, on 22-24 September 1997. Exposure to As in drinking water has been associated with the development of skin and internal cancers and noncarcinogenic effects such as diabetes, peripheral neuropathy, and cardiovascular diseases. There is little data on specific mechanism(s) of action for As, but a great deal of information on possible modes of action. Alth...

  11. Non-dissipative hydrodynamics : effective actions versus entropy current.

    Bhattacharya, Jyotirmoy; Bhattacharyya, Sayantani; Rangamani, Mukund

    2013-01-01

    While conventional hydrodynamics incorporating dissipative effects is hard to derive from an action principle, it is nevertheless possible to construct classical actions when the dissipative terms are switched off. In this note we undertake a systematic exploration of such constructions from an effective field theory approach and argue for the existence of non-trivial second order non-dissipative hydrodynamics involving pure energy-momentum transport. We find these fluids to be characterized ...

  12. Quantum effective action from the AdS/CFT correspondence

    Skenderis, K; Skenderis, Kostas; Solodukhin, Sergey N.

    2000-01-01

    We obtain an Einstein metric of constant negative curvature given an arbitrary boundary metric in three dimensions, and a conformally flat one given an arbitrary conformally flat boundary metric in other dimensions. In order to compute the on-shell value of the gravitational action for these solutions, we propose to integrate the radial coordinate from the boundary till a critical value where the bulk volume element vanishes. The result, which is a functional of the boundary metric, provides a sector of the quantum effective action common to all conformal field theories that have a gravitational description. We verify that the so-defined boundary effective action is conformally invariant in odd (boundary) dimensions and has the correct conformal anomaly in even (boundary) dimensions. In three dimensions and for arbitrary static boundary metric the bulk metric takes a rather simple form. We explicitly carry out the computation of the corresponding effective action and find that it equals the non-local Polyakov...

  13. Urban Heat Island Effect Actions - Neighborhood Data

    Louisville Metro Government — The urban heat island effect — defined as the difference in temperature between the core of Louisville and its suburbs — contributes to heat-related illnesses and...

  14. Effect of mutagen combined action on Chlamydomonas reinhardtii cells. II

    The effect of UV radiation and UV radiation combined with alkylnitrosourea derivatives (N-methyl-N-nitrosourea and N-ethyl-N-nitrosourea) was observed on survival of cells of the algae Chlamydomonas reinhardtii. In particular, single parts were evaluated of the overall lethal effect - dying of cells before division and dying of cells after division. It was found that the combined action of low doses of UV radiation and alkylnitrosoureas result in a pronounced protective effect which manifests itself by a higher frequency of surviving cells than was that effected by the action of alkylnitrosoureas alone. As a result of combined action with higher doses of UV radiation this effect is lost, and the resultant values will come close to the theoretically anticipated values. This gradual transition from a protective to an additive effect mainly manifests itself by changes in the proportion of cells dying before division. (author)

  15. Radiosensitizers action on Iodine 131 therapeutical effect

    Present studies were aimed to research the possible application of a radiosensitizer, nicotinamide, to increase the therapeutical effect of radioiodine. There were used goitrous and normal rats with growing dose of Iodine 131, with and without simultaneous treatment with nicotinamide. The obtained results show that the nicotinamide treatment importantly increases the thyroid radio destructive effect induced by radioiodine. Under these experimental conditions, nicotinamide induces to a significant increase of thyroid vascularisation, without changes in the proteins ADP-ribosylation activity. These results show, for the first time, the radiosensitizer effect of nicotinamide in front of Iodine 131 and give the possibility of using it in the treatment of hyperthyroid or thyroid difference cancer patients. (author)

  16. Fractional Effective Action at strong electromagnetic fields

    Kleinert, Hagen; Xue, She-Sheng

    2013-01-01

    In 1936, Weisskopf showed that for vanishing electric or magnetic fields the strong-field behavior of the one loop Euler-Heisenberg effective Lagrangian of quantum electro dynamics (QED) is logarithmic. Here we generalize this result for different limits of the Lorentz invariants \\(\\vec{E}^2-\\vec{B}^2\\) and \\(\\vec{B}\\cdot\\vec{E}\\). The logarithmic dependence can be interpreted as a lowest-order manifestation of an anomalous power behavior of the effective Lagrangian of QED, with critical exponents \\(\\delta=e^2/(12\\pi)\\) for spinor QED, and \\(\\delta_S=\\delta/4\\) for scalar QED.

  17. Background independent effective action from D=1 matrix model

    We derive the background independent form of the Das-Jevicki action. The tachyon terms are given to all orders by a generally covariant form of the Das-Jevicki action. The graviton-dilaton sector is the usual low energy effective action. This enables us to examine questions such as the back reaction of the tachyon on the metric. In particular the reason why the usual Liouville term is an exact solution of the conformal invariance conditions, as well as the fact that it has no back reaction, become manifest. We comment on the propagation of a tachyonic perturbation in the background of a black-hole metric. (orig.)

  18. Renormalization and Effective Actions for General Relativity

    Neugebohrn, Falk

    2007-01-01

    Quantum gravity is analyzed from the viewpoint of the renormalization group. The analysis is based on methods introduced by J. Polchinski concerning the perturbative renormalization with flow equations. In the first part of this work, the program of renormalization with flow equations is reviewed and then extended to effective field theories that have a finite UV cutoff. This is done for a scalar field theory by imposing additional renormalization conditions for some of the nonrenormalizable couplings. It turns out that one so obtains a statement on the predictivity of the effective theory at scales far below the UV cutoff. In particular, nonrenormalizable theories can be treated without problems in the proposed framework. In the second part, the standard covariant BRS quantization program for Euclidean Einstein gravity is applied. A momentum cutoff regularization is imposed and the resulting violation of the Slavnov-Taylor identities is discussed. Deriving Polchinski's renormalization group equation for Eucl...

  19. Renormalization and effective actions for general relativity

    Quantum gravity is analyzed from the viewpoint of the renormalization group. The analysis is based on methods introduced by J. Polchinski concerning the perturbative renormalization with flow equations. In the first part of this work, the program of renormalization with flow equations is reviewed and then extended to effective field theories that have a finite UV cutoff. This is done for a scalar field theory by imposing additional renormalization conditions for some of the nonrenormalizable couplings. It turns out that one so obtains a statement on the predictivity of the effective theory at scales far below the UV cutoff. In particular, nonrenormalizable theories can be treated without problems in the proposed framework. In the second part, the standard covariant BRS quantization program for Euclidean Einstein gravity is applied. A momentum cutoff regularization is imposed and the resulting violation of the Slavnov-Taylor identities is discussed. Deriving Polchinski's renormalization group equation for Euclidean quantum gravity, the predictivity of effective quantum gravity at scales far below the Planck scale is investigated with flow equations. A fine-tuning procedure for restoring the violated Slavnov-Taylor identities is proposed and it is argued that in the effective quantum gravity context, the restoration will only be accomplished with finite accuracy. Finally, the no-cutoff limit of Euclidean quantum gravity is analyzed from the viewpoint of the Polchinski method. It is speculated whether a limit with nonvanishing gravitational constant might exist where the latter would ultimatively be determined by the cosmological constant and the masses of the elementary particles. (orig.)

  20. Renormalization and effective actions for general relativity

    Neugebohrn, F.

    2007-05-15

    Quantum gravity is analyzed from the viewpoint of the renormalization group. The analysis is based on methods introduced by J. Polchinski concerning the perturbative renormalization with flow equations. In the first part of this work, the program of renormalization with flow equations is reviewed and then extended to effective field theories that have a finite UV cutoff. This is done for a scalar field theory by imposing additional renormalization conditions for some of the nonrenormalizable couplings. It turns out that one so obtains a statement on the predictivity of the effective theory at scales far below the UV cutoff. In particular, nonrenormalizable theories can be treated without problems in the proposed framework. In the second part, the standard covariant BRS quantization program for Euclidean Einstein gravity is applied. A momentum cutoff regularization is imposed and the resulting violation of the Slavnov-Taylor identities is discussed. Deriving Polchinski's renormalization group equation for Euclidean quantum gravity, the predictivity of effective quantum gravity at scales far below the Planck scale is investigated with flow equations. A fine-tuning procedure for restoring the violated Slavnov-Taylor identities is proposed and it is argued that in the effective quantum gravity context, the restoration will only be accomplished with finite accuracy. Finally, the no-cutoff limit of Euclidean quantum gravity is analyzed from the viewpoint of the Polchinski method. It is speculated whether a limit with nonvanishing gravitational constant might exist where the latter would ultimatively be determined by the cosmological constant and the masses of the elementary particles. (orig.)

  1. Perception, action, and Roelofs effect: a mere illusion of dissociation.

    Paul Dassonville

    2004-11-01

    Full Text Available A prominent and influential hypothesis of vision suggests the existence of two separate visual systems within the brain, one creating our perception of the world and another guiding our actions within it. The induced Roelofs effect has been described as providing strong evidence for this perception/action dissociation: When a small visual target is surrounded by a large frame positioned so that the frame's center is offset from the observer's midline, the perceived location of the target is shifted in the direction opposite the frame's offset. In spite of this perceptual mislocalization, however, the observer can accurately guide movements to the target location. Thus, perception is prone to the illusion while actions seem immune. Here we demonstrate that the Roelofs illusion is caused by a frame-induced transient distortion of the observer's apparent midline. We further demonstrate that actions guided to targets within this same distorted egocentric reference frame are fully expected to be accurate, since the errors of target localization will exactly cancel the errors of motor guidance. These findings provide a mechanistic explanation for the various perceptual and motor effects of the induced Roelofs illusion without requiring the existence of separate neural systems for perception and action. Given this, the behavioral dissociation that accompanies the Roelofs effect cannot be considered evidence of a dissociation of perception and action. This indicates a general need to re-evaluate the broad class of evidence purported to support this hypothesized dissociation.

  2. Boldine action against the stannous chloride effect.

    Reiniger, I W; Ribeiro da Silva, C; Felzenszwalb, I; de Mattos, J C; de Oliveira, J F; da Silva Dantas, F J; Bezerra, R J; Caldeira-de-Araújo, A; Bernardo-Filho, M

    1999-12-15

    Peumus boldus extract has been used in popular medicine in the treatment of biliar litiase, hepatic insufficiency and liver congestion. Its effects are associated to the substance boldine that is present in its extract. In the present work, we evaluated the influence of boldine both in: (i) the structural conformation of a plasmid pUC 9.1 through gel electrophoresis analysis; and in (ii) the survival of the strain of Escherichia coli AB1157 submitted to reactive oxygen species (ROS), generated by a Fenton like reaction, induced by stannous chloride. Our results show a reduction of the lethal effect induced by stannous chloride on the survival of the E. coli culture in the presence of boldine. The supercoiled form of the plasmid is not modified by stannous chloride in the presence of boldine. We suggest that the protection induced by boldine could be explained by its anti-oxidant mechanism. In this way, the boldine could be reacting with stannous ions, protecting them against the oxidation and, consequently, avoiding the generation of ROS. PMID:10624900

  3. On the new definition of off-shell effective action

    We analyze the recently proposed definition of the off-shell, gauge invariant, gauge-independent, effective action GAMMA, utilizing an invariant metric on the field space. It is shown how to establish correspondence between GAMMA and the standard effective action, calculated in some particular (Landau-type) gauge. Several examples are explicitly discussed, including Yang-Mills theory, the effective potential in scalar QED, and one-loop quantum gravity. Generalization to the case of super-invariant theories (e.g. super-Yang Mills and supergravity) is also presented. (orig.)

  4. Stratospheric ozone loss, ultraviolet effects and action spectroscopy

    Coohill, Thomas P.

    The major effect of stratospheric ozone loss will be an increase in the amount of ultraviolet radiation reaching the ground. This increase will be entirely contained within the UV-B (290-320nm). How this will impact life on Earth will be determined by the UV-B photobiology of exposed organisms, including humans. One of the analytical methods useful in estimating these effects is Action Spectroscopy (biological effect as a function of wavelength). Carefully constructed action spectra will allow us to partially predict the increase in bio-effect due to additional UV exposure. What effect this has on the organism and the system in which the organism resides is of paramount importance. Suitable action spectra already exist for human skin cancer, human cell mutation and killing, and for one immune response. Comprehensive and widely applicable action spectra for terrestrial and aquatic plant responses are being generated but are not yet suitable for extensive analysis. There is little data available for animals, other than those experiments completed in the laboratory as model systems for human studies. Some polychromatic action spectra have proven useful in determining the possible impact of ozone loss on biological systems. The pitfalls and limits of this approach will be addressed.

  5. Constraining the effective action by a method of external sources

    Garbrecht, Björn; Millington, Peter

    2016-05-01

    We propose a novel method of evaluating the effective action, wherein the physical one- and two-point functions are obtained in the limit of non-vanishing external sources. We illustrate the self-consistency of this method by recovering the usual 2PI effective action due to Cornwall, Jackiw and Tomboulis, differing only by the fact that the saddle-point evaluation of the path integral is performed along the extremal quantum, rather than classical, path. As such, this approach is of particular relevance to situations where the dominant quantum and classical paths are non-perturbatively far away from one-another. A pertinent example is the decay of false vacua in radiatively-generated potentials, as may occur for the electroweak vacuum of the Standard Model. In addition, we describe how the external sources may instead be chosen so as to yield the two-particle-point-irreducible (2PPI) effective action of Coppens and Verschelde. Finally, in the spirit of the symmetry-improved effective action of Pilaftsis and Teresi, we give an example of how the external sources can be used to preserve global symmetries in truncations of the 2PI effective action. Specifically, in the context of an O (2) model with spontaneous symmetry breaking, we show that this approach allows the Hartree-Fock approximation to be re-organized, such that the Goldstone boson remains massless algebraically in the symmetry-broken phase and we obtain the correct second-order thermal phase transition.

  6. Effective action of softly broken supersymmetric theories

    We study the renormalization of (softly) broken supersymmetric theories at the one loop level in detail. We perform this analysis in a superspace approach in which the supersymmetry breaking interactions are parameterized using spurion insertions. We comment on the uniqueness of this parameterization. We compute the one loop renormalization of such theories by calculating superspace vacuum graphs with multiple spurion insertions. To preform this computation efficiently we develop algebraic properties of spurion operators, that naturally arise because the spurions are often surrounded by superspace projection operators. Our results are general apart from the restrictions that higher super covariant derivative terms and some finite effects due to non-commutativity of superfield dependent mass matrices are ignored. One of the soft potentials induces renormalization of the Kaehler potential. (author)

  7. Early markers of ongoing action-effect learning

    Hannes eRuge

    2012-11-01

    Full Text Available Acquiring knowledge about the relationship between stimulus conditions, one’s own actions, and the resulting consequences or effects, is one prerequisite for intentional action. Previous studies have shown that such contextualized associations between actions and their effects (S-R-E associations can be picked up very quickly. The present study examined how such weakly practiced associations might affect overt behavior during the process of initial learning and during subsequent retrieval, and how these two measures are inter-related. We examined incidental (S-R-E learning in the context of trial-and-error S-R learning and in the context of instruction-based S-R learning. Furthermore, as a control condition, common outcome (CO learning blocks were included in which all responses produced one common sound effect, hence precluding differential (S-R-E learning. Post-learning retrieval of R-E associations was tested by re-using previously produced sound effects as novel imperative stimuli combined with actions that were either compatible or incompatible with the previously encountered R-E mapping. The central result was that the size of the compatibility effect could be predicted by the size of relative response slowing during ongoing learning in the preceding acquisition phase, both in trial-and-error learning and in instruction-based learning. Importantly, this correlation was absent for the common outcome control condition, precluding accounts based on unspecific factors. Instead, the results suggest that differential outcomes are ‘actively’ integrated into action planning and that this takes additional planning time. We speculate that this might be especially true for weakly practiced (S-R-E associations before an initial goal-directed action mode transitions into a more stimulus-based action mode.

  8. 10D = eesti disainer + soome firma / Ilona Gurjanova

    Gurjanova, Ilona, 1958-

    2006-01-01

    Koostööprojektist, mille tulemusena pidi valmima kümnel eesti disaineril soome mööblitootja poolt tellitud mööbliese, mille valmistab eesti tootja. 10D disainikonkursi võitjad: I koht -Igor Volkov, lastetool "Dixi", II - Martin Pärn, istepink "Kosta", Tarmo Luisk, pehme järi "Dog", ära märgiti Ilona Gurjanova graafiliselt kujundatud kahhelkivid ja ürituse tunnusgraafika

  9. The Geometric Construction of WZW Effective Action in Noncommutative Manifold

    HOU BoYu; WANG YongQiang; YANG ZhanYing; YUE RuiHong

    2002-01-01

    By constructing close-one-cochain density in the gauge group space we get the Wess Zumino Witten(WZW) effective Lagrangian on high-dimensional noncommutative space. Especially consistent anomalies derived fromthis WZW effective action in noncommutative four-dimensional space coincide with those obtained by L. Bonora etc.(hep-th /0002210).

  10. The Geometric Construction of WZW Effective Action in Noncommutative Manifold

    2002-01-01

    By constructing close-one-cochain density Ω12n in the gauge group space we get the Wess-Zumino-Witten (WZW) effective Lagrangian on high-dimensional noncommutative space.Especially consistent anomalies derived from this WZW effective action in noncommutative four-dimensional space coincide with those obtained by L.Bonora etc.(het-th/0002210).

  11. Laxative effects and mechanism of action of Brazilian green propolis

    Kakino Mamoru; Izuta Hiroshi; Tsuruma Kazuhiro; Araki Yoko; Shimazawa Masamitsu; Ichihara Kenji; Hara Hideaki

    2012-01-01

    Abstract Background Brazilian green propolis is reported to have wide range of biological properties including antibacterial, anti-inflammatory, anti-influenza, and antioxidant activities. In the digestive system, a protective effect of propolis on gastric ulcer has been reported, but a laxative effect has not yet been reported. We investigated the effect and the mechanism of action of water and ethanol extracts of Brazilian green propolis. Methods We examined the laxative effect of propolis ...

  12. Action and perception in social contexts: Intentional binding for social action effects

    Roland Pfister

    2014-09-01

    Full Text Available The subjective experience of controlling events in the environment alters the perception of these events. For instance, the interval between one’s own actions and their consequences is subjectively compressed – a phenomenon known as intentional binding. In two experiments, we studied intentional binding in a social setting in which actions of one agent prompted a second agent to perform another action. Participants worked in pairs and were assigned to a “leader” and a “follower” role, respectively. The leader’s key presses triggered (after a variable interval a tone effect and this tone served as go signal for the follower to perform a keypress as well. Leaders and followers estimated the interval between the leader’s keypress and the following tone, or the interval between the tone and the follower’s keypress. The leader showed reliable intentional binding for both intervals relative to the follower’s estimates. These results indicate that human agents experience a pre-reflective sense of agency for genuinely social consequences of their actions.

  13. Non-dissipative hydrodynamics: Effective actions versus entropy current

    Bhattacharya, Jyotirmoy; Rangamani, Mukund

    2012-01-01

    While conventional hydrodynamics incorporating dissipative effects is hard to derive from an action principle, it is nevertheless possible to construct classical actions when the dissipative terms are switched off. In this note we undertake a systematic exploration of such constructions from an effective field theory approach and argue for the existence of non-trivial second order non-dissipative hydrodynamics involving pure energy-momentum transport. We find these fluids to be characterized by five second-order transport coefficients based on the effective action (a three parameter family is Weyl invariant). On the other hand since all flows of such fluids are non-dissipative, they entail zero entropy production; one can therefore understand them using the entropy current formalism which has provided much insight into hydrodynamic transport. An analysis of the most general stress tensor with zero entropy production however turns out to give a seven parameter family of non-dissipative hydrodynamics (a four pa...

  14. Effective actions near singularities: the STU-model

    We derive the low energy effective action of the STU-model in four and five dimensions near the line T=U where SU(2) gauge symmetry enhancement occurs. By 'integrating in' the light W± bosons together with their superpartners, the quantum corrected effective action becomes non-singular at T=U and manifestly SU(2) invariant. The four-dimensional theory is found to be consistent with modular invariance and the five-dimensional decompactification limit. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  15. Anomalous effective action, Noether current, Virasoro algebra and Horizon entropy

    Several investigations show that in a very small length scale there exist corrections to the entropy of black hole horizon. Due to fluctuations of the background metric and the external fields the action incorporates corrections. In the low energy regime, the one-loop effective action in four dimensions leads to trace anomaly. We start from the Noether current corresponding to the Einstein-Hilbert plus the one-loop effective action to calculate the charge for the diffeomorphisms which preserve the Killing horizon structure. Then a bracket for the charges is calculated. We show that the Fourier modes of the bracket are exactly similar to the Virasoro algebra. Then using the Cardy formula the entropy is evaluated. Finally, the explicit terms of the entropy expression is calculated for a classical background. It turns out that the usual expression for the entropy; i.e. the Bekenstein-Hawking form, is not modified. (orig.)

  16. Effective action for the field equations of charged black holes

    We consistently reduce the equations of motion for the bosonic N = 2 supergravity action, using a multi-centered black hole ansatz for the metric. This reduction is done in a general, non-supersymmetric setup, in which we extend concepts of BPS black hole technology. First we obtain a more general form of the black hole potential, as part of an effective action for both the scalars and the vectors in the supergravity theory. Furthermore, we show that there are extra constraints specifying the solution, which we calculate explicitly. In the literature, these constraints have already been studied in the one-center case. We also show that the effective action we obtain for non-static metrics can be linked to the 'entropy function' for the spherically symmetric case, as defined by Sen (2005 J. High Energy Phys. JHEP09(2005)038) and Cardoso et al (2007 J. High Energy Phys. JHEP03(2007)085)

  17. Resummed effective action in the world-line formalism

    Auer, T; Zahlten, C; Auer, Thomas; Schmidt, Michael G.; Zahlten, Claus

    2004-01-01

    Using the world-line method we resum the scalar one-loop effective action. This is based on an exact expression for the one-loop action obtained for a background potential and a Taylor expansion of the potential up to quadratic order in x-space. We thus reproduce results of Masso and Rota very economically. An alternative resummation scheme is suggested using ``center of mass'' based loops which is equivalent under the assumption of vanishing third and higher derivatives in the Taylor expansion but leads to simplified expressions. In an appendix some general issues concerning the relation between world-line integrals with fixed end points versus integrals with fixed center are clarified. We finally note that this method is also very valuable for gauge field effective actions where it is based on the Euler--Heisenberg type resummation.

  18. Resumed effective action in the world-line formalism

    Using the world-line method we resume the scalar one-loop effective action. This is based on an exact expression for the one-loop action obtained for a background potential and a Taylor expansion of the potential up to quadratic order in x-space. We thus reproduce results of Masso and Rota very economically. An alternative resummation scheme is suggested using 'center of mass' based loops which is equivalent under the assumption of vanishing third and higher derivatives in the Taylor expansion but leads to simplified expressions. In an Appendix A some general issues concerning the relation between world-line integrals with fixed end points versus integrals with fixed center are clarified. We finally note that this method is also very valuable for gauge field effective actions where it is based on the Euler-Heisenberg type resummation

  19. Brane Effective Actions, Kappa-Symmetry and Applications

    Simon, Joan

    2011-01-01

    This is a review on brane effective actions, their symmetries and some of its applications. Its first part uncovers the Green-Schwarz formulation of single M- and D-brane effective actions focusing on kinematical aspects : the identification of their degrees of freedom, the importance of world volume diffeomorphisms and kappa symmetry, to achieve manifest spacetime covariance and supersymmetry, and the explicit construction of such actions in arbitrary on-shell supergravity backgrounds. Its second part deals with applications. First, the use of kappa symmetry to determine supersymmetric world volume solitons. This includes their explicit construction in flat and curved backgrounds, their interpretation as BPS states carrying (topological) charges in the supersymmetry algebra and the connection between supersymmetry and hamiltonian BPS bounds. When available, I emphasise the use of these solitons as constituents in microscopic models of black holes. Second, the use of probe approximations to infer about non-tr...

  20. Effective action approach to wave propagation in scalar QED plasmas

    Shi, Yuan; Qin, Hong

    2016-01-01

    A relativistic quantum field theory with nontrivial background fields is developed and applied to study waves in plasmas. The effective action of the electromagnetic 4-potential is calculated ab initio from the standard action of scalar QED using path integrals. The resultant effective action is gauge invariant and contains nonlocal interactions, from which gauge bosons acquire masses without breaking the local gauge symmetry. To demonstrate how the general theory can be applied, we study a cold unmagnetized plasma and a cold uniformly magnetized plasma. Using these two examples, we show that all linear waves well-known in classical plasma physics can be recovered from relativistic quantum results when taking the classical limit. In the opposite limit, classical wave dispersion relations are modified substantially. In unmagnetized plasmas, longitudinal waves propagate with nonzero group velocities even when plasmas are cold. In magnetized plasmas, anharmonically spaced Bernstein waves persist even when plasma...

  1. Constraining the effective action by a method of external sources

    Garbrecht, Bjorn

    2015-01-01

    We propose a novel method of evaluating the effective action, wherein the physical one- and two-point functions are obtained in the limit of non-vanishing external sources. We illustrate the self-consistency of this method by recovering the usual 2PI effective action due to Cornwall, Jackiw and Tomboulis, differing only by the fact that the saddle-point evaluation of the path integral is performed along the extremal quantum, rather than classical, path. As such, this approach is of particular relevance to situations where the dominant quantum and classical paths are non-perturbatively far away from one-another. A pertinent example is the decay of false vacua in radiatively-generated potentials, as may occur for the electroweak vacuum of the Standard Model. In addition, we describe how the external sources may instead be chosen so as to yield the two-particle-point-irreducible (2PPI) effective action of Coppens and Verschelde. Finally, in the spirit of the symmetry-improved effective action of Pilaftsis and Te...

  2. Action Research: Effective Marketing Strategies for a Blended University Program

    Cook, Ruth Gannon; Ley, Kathryn

    2008-01-01

    This action research study investigated a marketing plan based on collaboration among a program faculty team and other organizational units for a graduate professional program. From its inception through the second year of operation, program enrollment increased due to the marketing plan based on an effective approach grounded in simple marketing…

  3. Zeta function regularization and effective action in curved spacetime. 16

    This article expounds on a sophisticated regularization technique for quantum field theories in arbitrary gravitational fields: the zeta function regularization. The effective action in curved spacetime is obtained and used to discuss phase transitions in the De Sitter Universe. (author). 5 refs.; 6 figs.; 1 tab

  4. Boundary Conditions for NHEK through Effective Action Approach

    We study the asymptotic symmetry group (ASG) of the near horizon geometry of extreme Kerr black hole through the effective action approach developed by Porfyriadis and Wilczek (arXiv:1007.1031v1[gr-qc]). By requiring a finite boundary effective action, we derive a new set of asymptotic Killing vectors and boundary conditions, which are much more relaxed than the ones proposed by Matsuo Y et al. [Nucl. Phys. B 825 (2010) 231], and still allow a copy of a conformal group as its ASG. In the covariant formalism, the asymptotic charges are finite, with the corresponding central charge vanishing. By using the quasi-local charge and introducing a plausible cut-off, we find that the higher order terms of the asymptotic Killing vectors, which could not be determined through the effective action approach, contribute to the central charge as well. We also show that the boundary conditions suggested by Guica et al. [Phys. Rev. D 80 (2009) 124008] lead to a divergent first-order boundary effective action. (the physics of elementary particles and fields)

  5. Effective action for a quantum scalar field in warped spaces

    Hoff da Silva, J.M.; Mendonca, E.L.; Scatena, E. [Universidade Estadual Paulista ' ' Julio de Mesquita Filho' ' -UNESP, Departamento de Fisica e Quimica, Guaratingueta, SP (Brazil)

    2015-11-15

    We investigate the one-loop corrections, at zero as well as finite temperature, of a scalar field taking place in a braneworld motivated warped background. After to reach a well-defined problem, we calculate the effective action with the corresponding quantum corrections to each case. (orig.)

  6. Finiteness of the Coulomb gauge QCD perturbative effective action

    Andraši, A., E-mail: aandrasi@irb.hr [Vlaška 58, Zagreb (Croatia); Taylor, J.C., E-mail: jct@damtp.cam.ac.uk [DAMTP, University of Cambridge, Cambridge (United Kingdom)

    2015-05-15

    At 2-loop order in the Coulomb gauge, individual Feynman graphs contributing to the effective action have energy divergences. It is proved that these cancel in suitable combinations of graphs. This has previously been shown only for transverse external fields. The calculation results in a generalization of the Christ–Lee term which was inserted into the Hamiltonian.

  7. Finiteness of the Coulomb gauge QCD perturbative effective action

    Andrasi, A

    2015-01-01

    At 2-loop order in the Coulomb gauge, individual Feynman graphs contributing to the effective action have energy divergences. It is proved that these cancel in suitable combinations of graphs. This has previously been shown only for transverse external fields. The calculation results in a generalization of the Christ-Lee term which was inserted into the Hamiltonian.

  8. Effective action approach to dynamical generation of fermion mixing

    Blasone, Massimo; Smaldone, Luca

    2016-01-01

    In this paper we discuss a mechanism for the dynamical generation of flavor mixing, in the framework of the Nambu--Jona Lasinio model. Our approach is illustrated both with the conventional operatorial formalism and with functional integral and ensuing one-loop effective action. The results obtained are briefly discussed.

  9. Effective action for the Abelian Higgs model in FLRW

    George, Damien P; Postma, Marieke

    2012-01-01

    We compute the divergent contributions to the one-loop action of the U(1) Abelian Higgs model. The calculation allows for a Friedmann-Lemaitre-Robertson-Walker space-time and a time-dependent expectation value for the scalar field. Treating the time-dependent masses as two-point interactions, we use the in-in formalism to compute the first, second and third order graphs that contribute quadratic and logarithmic divergences to the effective scalar action. Working in R-xi gauge we show that the result is gauge invariant upon using the equations of motion.

  10. Effective action for the Abelian Higgs model in FLRW

    George, Damien P.; Mooij, Sander(Nikhef, Science Park 105, Amsterdam, 1098 XG The Netherlands); Postma, Marieke

    2012-01-01

    We compute the divergent contributions to the one-loop action of the U(1) Abelian Higgs model. The calculation allows for a Friedmann-Lemaitre-Robertson-Walker space-time and a time-dependent expectation value for the scalar field. Treating the time-dependent masses as two-point interactions, we use the in-in formalism to compute the first, second and third order graphs that contribute quadratic and logarithmic divergences to the effective scalar action. Working in R-xi gauge we show that the...

  11. Effect of mutagen combined action on Chlamydomonas Reinhardtii cells. I

    The effect was investigated of single and combined actions of alkylnitrosourea derivatives (N-methyl-N-nitrosourea and N-ethyl-N-nitrosourea) and UV-radiation on the survival of cells of Chlamydomonas reinhardtii algae in dependence on the sequence of application of mutagens and on the given conditions of cultivation following mutagen activity. In particular, the single phases were investigated of the total lethal effect, i.e., the death of cells before division and their death after division. The most pronounced changes in dependence on the sequence of application of mutagens and on the given conditions of cultivation were noted in cell death before division. In dependence on the sequence of application of mutagens, the effect of the combined action on the survival of cells changed from an additive (alkylnitrosourea + UV-radiation) to a protective effect (UV-radiation + alkylnitrosourea). (author)

  12. Computing the Effective Action with the Functional Renormalization Group

    Codello, Alessandro; Rachwal, Leslaw; Tonero, Alberto

    2015-01-01

    The "exact" or "functional" renormalization group equation describes the renormalization group flow of the effective average action $\\Gamma_k$. The ordinary effective action $\\Gamma_0$ can be obtained by integrating the flow equation from an ultraviolet scale $k=\\Lambda$ down to $k=0$. We give several examples of such calculations at one-loop, both in renormalizable and in effective field theories. We use the results of Barvinsky, Vilkovisky and Avramidi on the non-local heat kernel coefficients to reproduce the four point scattering amplitude in the case of a real scalar field theory with quartic potential and in the case of the pion chiral lagrangian. In the case of gauge theories, we reproduce the vacuum polarization of QED and of Yang-Mills theory. We also compute the two point functions for scalars and gravitons in the effective field theory of scalar fields minimally coupled to gravity.

  13. Computing the effective action with the functional renormalization group

    Codello, Alessandro; Percacci, Roberto; Rachwał, Lesław; Tonero, Alberto

    2016-04-01

    The "exact" or "functional" renormalization group equation describes the renormalization group flow of the effective average action Γ _k. The ordinary effective action Γ _0 can be obtained by integrating the flow equation from an ultraviolet scale k=Λ down to k=0. We give several examples of such calculations at one-loop, both in renormalizable and in effective field theories. We reproduce the four-point scattering amplitude in the case of a real scalar field theory with quartic potential and in the case of the pion chiral Lagrangian. In the case of gauge theories, we reproduce the vacuum polarization of QED and of Yang-Mills theory. We also compute the two-point functions for scalars and gravitons in the effective field theory of scalar fields minimally coupled to gravity.

  14. Action video game training reduces the Simon Effect.

    Hutchinson, Claire V; Barrett, Doug J K; Nitka, Aleksander; Raynes, Kerry

    2016-04-01

    A number of studies have shown that training on action video games improves various aspects of visual cognition including selective attention and inhibitory control. Here, we demonstrate that action video game play can also reduce the Simon Effect, and, hence, may have the potential to improve response selection during the planning and execution of goal-directed action. Non-game-players were randomly assigned to one of four groups; two trained on a first-person-shooter game (Call of Duty) on either Microsoft Xbox or Nintendo DS, one trained on a visual training game for Nintendo DS, and a control group who received no training. Response times were used to contrast performance before and after training on a behavioral assay designed to manipulate stimulus-response compatibility (the Simon Task). The results revealed significantly faster response times and a reduced cost of stimulus-response incompatibility in the groups trained on the first-person-shooter game. No benefit of training was observed in the control group or the group trained on the visual training game. These findings are consistent with previous evidence that action game play elicits plastic changes in the neural circuits that serve attentional control, and suggest training may facilitate goal-directed action by improving players' ability to resolve conflict during response selection and execution. PMID:26238760

  15. The end-state comfort effect facilitates joint action.

    Herbort, Oliver; Koning, Arno; van Uem, Janet; G J Meulenbroek, Ruud

    2012-03-01

    Motor experts can accurately predict the future actions of others by observing their movements. This report describes three experiments that investigate such predictions in everyday object manipulations and test whether these predictions facilitate responses to the actions of others. Observing video excerpts showing an actor reaching for a vertically mounted dial, participants in Experiment 1 needed to predict how the actor would rotate it. Their predictions were specific to the direction and extent of the dial rotation and improved proportionate to the length of the video clip shown. Testing whether such predictions facilitate responses, in the subsequent experiments responders had to undo an actor's actions, back-rotating a dial (Exp 2) and a bar (Exp 3). The responders' actions were initiated faster when the actors' movements obeyed the so-called end-state comfort principle than when they did not. Our experiments show that humans exploit the end-state comfort effect to tweak their predictions of the future actions of others. The results moreover suggest that the precision of these predictions is mediated by perceptual learning rather than by motor simulation. PMID:22321453

  16. Invariant effective actions, cohomology of homogeneous spaces and anomalies

    D`Hoker, E. [California Univ., Los Angeles, CA (United States). Dept. of Physics

    1995-10-02

    We construct the most general local effective actions for Goldstone boson fields associated with spontaneous symmetry breakdown from a group G to a subgroup H. In a preceding paper, it was shown that any G-invariant term in the action, which results from a non-invariant Lagrangian density, corresponds to a non-trivial generator of the de Rham cohomology classes of G/H. Here, we present an explicit construction of all the generators of this cohomology for any coset space G/H and compact, connected group G. Generators contributing to actions in 4-dimensional space-time arise either as products of generators of lower degree such as the Goldstone-Wilczek current, or are of the Wess-Zumino-Witten type. The latter arise if and only if G has a non-zero G-invariant symmetric d-symbol, which vanishes when restricted to the subgroup H, i.e. when G has anomalous representations in which H is embedded in an anomaly free way. Coupling of additional gauge fields leads to actions whose gauge variation coincides with the chiral anomaly, which is carried here by Goldstone boson fields at tree level. Generators contributing to actions in 3-dimensional space-time arise as Chern-Simons terms evaluated on connections that are composites of the Goldstone field. (orig.).

  17. Invariant effective actions, cohomology of homogeneous spaces and anomalies

    We construct the most general local effective actions for Goldstone boson fields associated with spontaneous symmetry breakdown from a group G to a subgroup H. In a preceding paper, it was shown that any G-invariant term in the action, which results from a non-invariant Lagrangian density, corresponds to a non-trivial generator of the de Rham cohomology classes of G/H. Here, we present an explicit construction of all the generators of this cohomology for any coset space G/H and compact, connected group G. Generators contributing to actions in 4-dimensional space-time arise either as products of generators of lower degree such as the Goldstone-Wilczek current, or are of the Wess-Zumino-Witten type. The latter arise if and only if G has a non-zero G-invariant symmetric d-symbol, which vanishes when restricted to the subgroup H, i.e. when G has anomalous representations in which H is embedded in an anomaly free way. Coupling of additional gauge fields leads to actions whose gauge variation coincides with the chiral anomaly, which is carried here by Goldstone boson fields at tree level. Generators contributing to actions in 3-dimensional space-time arise as Chern-Simons terms evaluated on connections that are composites of the Goldstone field. (orig.)

  18. Surgical removal of visceral adipose tissue: effects on insulin action.

    Gabriely, Ilan; Barzilai, Nir

    2003-06-01

    Many studies have demonstrated that excess of visceral fat has deleterious effects on insulin action. Mainly, it has been shown to be associated with a decrease in hepatic and peripheral insulin sensitivity, which results in a clinical condition also known as insulin resistance. This report describes a novel experimental method that we employed in order to analyze the particular effects of visceral fat on insulin activity. By extracting visceral fat we were able to distinguish the specific role that it plays in insulin action, and to analyze its effects on the gene expression of a variety of fat-derived peptides, which may be considered to be (at least partially) mediators in the development of the metabolic syndrome and possibly diabetes mellitus. PMID:12762966

  19. Effect of exercise on insulin action in human skeletal muscle

    Richter, Erik; Mikines, K J; Galbo, Henrik;

    1989-01-01

    performed. Increased insulin action on glucose uptake was found in the exercised compared with the rested thigh at mean plasma insulin concentrations of 23, 40, and 410 microU/ml. Furthermore, prior contractions directed glucose uptake toward glycogen synthesis and increased insulin effects on thigh O2......The effect of 1 h of dynamic one-legged exercise on insulin action in human muscle was studied in 6 healthy young men. Four hours after one-legged knee extensions, a three-step sequential euglycemic hyperinsulinemic clamp combined with arterial and bilateral femoral vein catheterization was...... consumption and at some insulin concentrations on potassium exchange. In contrast, no change in insulin effects on limb exchange of free fatty acids, glycerol, alanine or tyrosine were found after exercise. Glycogen concentration in rested vastus lateralis muscle did not increase measurably during the clamp...

  20. Effective action for scalar fields in two-dimensional gravity

    We consider a general two-dimensional gravity model minimally or nonminimally coupled to a scalar field. The canonical form of the model is elucidated, and a general solution of the equations of motion in the massless case is reviewed. In the presence of a scalar field all geometric fields (zweibein and Lorentz connection) are excluded from the model by solving exactly their Hamiltonian equations of motion. In this way the effective equations of motion and the corresponding effective action for a scalar field are obtained. It is written in a Minkowskian space-time and does not include any geometric variables. The effective action arises as a boundary term and is nontrivial both for open and closed universes. The reason is that unphysical degrees of freedom cannot be compactly supported because they must satisfy the constraint equation. As an example we consider spherically reduced gravity minimally coupled to a massless scalar field. The effective action is used to reproduce the Fisher and Roberts solutions

  1. One-loop effective actions and higher spins

    Bonora, L; Prester, P Dominis; Giaccari, S; De Souza, B Lima; Stemberga, T

    2016-01-01

    The idea we advocate in this paper is that the one-loop effective action of a free (massive) field theory coupled to external sources (via conserved currents) contains complete information about the classical dynamics of such sources. We show many explicit examples of this fact for (scalar and fermion) free field theories in various dimensions $d=3,4,5,6$ coupled to (bosonic, completely symmetric) sources with a number of spins. In some cases we also provide compact formulas for any dimension. This paper is devoted to two-point correlators, so the one-loop effective action we construct contains only the quadratic terms and the relevant equations of motion for the sources we obtain are the linearized ones.

  2. Misunderstanding that the Effective Action is Convex under Broken Symmetry

    Asanuma, Nobu-Hiko

    2016-01-01

    The widespread belief that the effective action is convex and has a flat bottom under broken global symmetry is shown to be wrong. We show spontaneous symmetry breaking necessarily accompanies non-convexity in the effective action for quantum field theory, or in the free energy for statistical mechanics, and clarify the magnitude of non-convexity. For quantum field theory, it is also explicitly proved that translational invariance breaks spontaneously when the system is in the non-convex region, and that different vacua of spontaneously broken symmetry cannot be superposed. As applications of non-convexity, we study the first-order phase transition which happens at the zero field limit of spontaneously broken symmetry, and we propose a simple model of phase coexistence which obeys the Born rule.

  3. Field theory without Feynman diagrams: One-loop effective actions

    In this paper the connection between standard perturbation theory techniques and the new Bern-Kosower calculational rules for gauge theory is clarified. For one-loop effective actions of scalars, Dirac spinors, and vector bosons in a background gauge field, Bern-Kosower type rules are derived without the use of either string theory or Feynman diagrams. The effective action is written as a one-dimensional path integral, which can be calculated to any order in the gauge coupling; evaluation leads to Feynman parameter integrals directly, bypassing the usual algebra required from Feynman diagrams, and leading to compact and organized expressions. This formalism is valid off-shell, is explicitly gauge invariant, and can be extended to a number of other field theories. (orig.)

  4. Laxative effects and mechanism of action of Brazilian green propolis

    Kakino Mamoru

    2012-10-01

    Full Text Available Abstract Background Brazilian green propolis is reported to have wide range of biological properties including antibacterial, anti-inflammatory, anti-influenza, and antioxidant activities. In the digestive system, a protective effect of propolis on gastric ulcer has been reported, but a laxative effect has not yet been reported. We investigated the effect and the mechanism of action of water and ethanol extracts of Brazilian green propolis. Methods We examined the laxative effect of propolis on stool frequency by administering orally an ethanol extract of propolis (EEP or a water extract of propolis (WEP at 10, 50, 100, or 500 mg/kg to normal mice. We then investigated the effects of propolis using constipation model mice induced by two types of drugs, loperamide (a μ opioid receptor agonist and clonidine (an α-2 adrenergic receptor agonist. We also investigated the effects of WEP on gastrointestinal transit and contractional tension of the ileum to uncover the mechanism of action of WEP. Results Treatment with WEP, but not with EEP, significantly increased the weight of stools (p Conclusion These findings indicate that WEP has laxative effects both in normal mice and in clonidine-induced constipation model mice. The laxative effects of WEP might be mediated by increased contractional tension of the ileum exerted at least in part via activation of an acetylcholine receptor.

  5. Light composite Higgs from an effective action for technicolor

    Doff, A.(Universidade Tecnológica Federal do Paraná – UTFPR – DAFIS, Av. Monteiro Lobato Km 04, 84016-210 Ponta Grossa, PR, Brazil); Natale, A. A.; da Silva, P. S. Rodrigues

    2008-01-01

    We compute an effective action for a composite Higgs boson formed by new fermions belonging to a general technicolor non-Abelian gauge theory, using a quite general expression for the fermionic self-energy that depends on a certain parameter (alpha), that defines the technicolor theory from the extreme walking behavior up to the one with a standard operator product expansion behavior. We discuss the values of the trilinear and quadrilinear scalar couplings. Our calculation spans all the possi...

  6. The effective action in Einstein-Maxwell theory

    Considerable work has been done on the one-loop effective action in combined electromagnetic and gravitational fields, particularly as a tool for determining the properties of light propagation in curved space. After a short review of previous work, I will present some recent results obtained using the worldline formalism. In particular, I will discuss various ways of generalizing the QED Euler-Heisenberg Lagrangians to the Einstein-Maxwell case.

  7. The effective action in Einstein-Maxwell theory

    Bastianelli, Fiorenzo; Davila, Jose Manuel; Schubert, Christian

    2008-01-01

    Considerable work has been done on the one-loop effective action in combined electromagnetic and gravitational fields, particularly as a tool for determining the properties of light propagation in curved space. After a short review of previous work, I present some recent results obtained using the worldline formalism. In particular, I will discuss various ways of generalizing the QED Euler-Heisenberg Lagrangian to the Einstein-Maxwell case.

  8. Brane Effective Actions, Kappa-Symmetry and Applications

    Joan Simón

    2012-02-01

    Full Text Available This is a review on brane effective actions, their symmetries and some of their applications. Its first part covers the Green–Schwarz formulation of single M- and D-brane effective actions focusing on kinematical aspects: the identification of their degrees of freedom, the importance of world volume diffeomorphisms and kappa symmetry to achieve manifest spacetime covariance and supersymmetry, and the explicit construction of such actions in arbitrary on-shell supergravity backgrounds. Its second part deals with applications. First, the use of kappa symmetry to determine supersymmetric world volume solitons. This includes their explicit construction in flat and curved backgrounds, their interpretation as Bogomol’nyi–Prasad–Sommerfield (BPS states carrying (topological charges in the supersymmetry algebra and the connection between supersymmetry and Hamiltonian BPS bounds. When available, I emphasise the use of these solitons as constituents in microscopic models of black holes. Second, the use of probe approximations to infer about the non-trivial dynamics of strongly-coupled gauge theories using the anti de Sitter/conformal field theory (AdS/CFT correspondence. This includes expectation values of Wilson loop operators, spectrum information and the general use of D-brane probes to approximate the dynamics of systems with small number of degrees of freedom interacting with larger systems allowing a dual gravitational description. Its final part briefly discusses effective actions for N D-branes and M2-branes. This includes both Super-Yang-Mills theories, their higher-order corrections and partial results in covariantising these couplings to curved backgrounds, and the more recent supersymmetric Chern–Simons matter theories describing M2-branes using field theory, brane constructions and 3-algebra considerations.

  9. Using the Psychology of Language to Effectively Communicate Actionable Science

    Hall, J. M.

    2014-12-01

    The words used to articulate science can have as significant a psychological impact on public perception as the data itself. It is therefore essential to utilize language that not only accurately relates the scientific information, but also effectively conveys a message that is congruent with the presenter's motivation for expressing the data. This is especially relevant for environmental subjects that are surrounded by emotionally charged, political discourses. For example are terms like catastrophe and disaster; while these words may accurately illustrate impartial scientific data, they will likely trigger psychological responses in audiences such as fear or denial that have a detrimental impact on the human decision making process. I propose a set of 5 key principles to assist in communicating data to the general public that both support the transfer of ideas and the presenter's intended psychological impact. 1) Articulate the underlying intentions that motivate the communication of data in a transparent manner 2) Use language congruent with the presenter's stated intentions 3) Maintain a neutral, non-judgmental attitude towards the complex human psychological and emotional dynamics present in a target audience 4) Demonstrate acceptance and compassion when analyzing past and present human actions that adversely affect the environment 5) Develop a perspective of non-attachment when proposing future actions and/or consequences of current human behaviors. The application of these 5 principles provides a framework to move from our current understanding of problems and solutions to effective physical action that allows us to gracefully adapt with our ever changing planet.

  10. Toward effective ecological risk-management of refinery corrective action

    Cleanup of complex industrial sites, such as refineries, requires risk-based decision tools to ensure that environmentally protective remediation is consistent with current and future land use. However, conventional ecological risk assessment approaches are not well suited for complex industrial sites. Site risk assessments focus on hypothetical chemical risk assuming diverse and undisturbed ecosystems, rather than industrial and disturbed area conditions. In addition, they offer little guidance as to how to make timely and effective risk management decisions. An innovative methodology is proposed to assist industry and regulatory risk managers with rapid EcoRisk reconnaissance and cost-effective remedial decision-making at complex industrial sites. Phase 1 comprises a three-step risk screening of areas of ecological concern at the site, which integrates habitat quality characteristics and potential chemical hazards. It yields an ordering of areas as follows: areas of no significant risk; areas of potentially significant risk; and areas of likely significant risk. A decision rule is then applied to determine appropriate risk management action, including: no action; additional study; and remedial or management action. In Phase 2, additional study is conducted for areas that exhibit potentially significant risk so as to facilitate risk management. This methodology is currently being applied at the 1,300 acre, former Exxon Bayway Refinery in New Jersey

  11. Effect of metal complexation to anti-inflammatory over the action against oxidative and free radicals: ketoprofen action

    Free radicals are highly reactive species generated in living organisms for the purpose of protection. However, in some circumstances, they are responsible for the occurrence or aggravation of tissue damage. Many anti-inflammatory drugs have a direct effect on free radicals and not radical reactive species, which contributes to its actions against inflammation. Ketoprofen is a nonsteroidal anti-inflammatory agent that generates free radicals by photo irradiation and has an important hemolytic effect with that. The complexation of metals to different drugs has been used as a strategy to improve the pharmacological action of different molecules and reduce their side effects. This paper presents the results of ketoprofen and their metallic complexes action on erythrocytes and free radicals. It was observed that the cerium enhances the scavenger properties of ketoprofen on free radicals, while copper enhances its action over non-radical oxidants. Copper also reduced the hemolytic effect presented by ketoprofen meanwhile its cerium derivative maintained it. (author)

  12. PARENTS' AUTHORITY AND THE EFFECTIVENESS OF THEIR EDUCATIONAL ACTIONS

    Romanowska-Tolloczko Anna

    2010-01-01

    Full Text Available Facing a gradual crisis of moral authority in the modern world, educationalists underline its importance in the education and upbringing process. The first and, for a long period of time, the most important authority for children are their parents, who often fail to understand the nature of their own significance and impact on the child. They often wrongly associate parental authority with unquestionable power and this faulty reasoning carries negative developmental implications as the child's submissiveness is not tantamount to acceptance and may result from his/her weakness or fear rather than from recognizing parental authority. This article is to emphasise that parents need to be fully aware of their own educational actions in the child upbringing process. It is important to understand that such actions affect the way parents are perceived by children. This article suggests a number of behaviours conducive to building and sustaining the sense of authority and respect as these features are fundamental in ensuring the effectiveness of educational actions undertaken by parents in the upbringing process.

  13. Side effect of acting on the world: Acquisition of action-outcome statistic relation alters visual interpretation of action outcome

    Takahiro eKawabe

    2013-09-01

    Full Text Available Humans can acquire the statistical features of the external world and employ them to control behaviors. Some external events occur in harmony with an agent’s action, and thus humans should also be able to acquire the statistical features between an action and its external outcome. We report that the acquired action-outcome statistical features alter the visual appearance of the action outcome. Pressing either of two assigned keys triggered visual motion whose direction was statistically biased either upward or downward, and observers judged the stimulus motion direction. Points of subjective equality (PSE for judging motion direction were shifted repulsively from the mean of the distribution associated with each key. Our Bayesian model accounted for the PSE shifts, indicating the optimal acquisition of the action-effect statistical relation. The PSE shifts were moderately attenuated when the action-outcome contingency was reduced. The Bayesian model again accounted for the attenuated PSE shifts. On the other hand, when the action-outcome contiguity was greatly reduced, the PSE shifts were greatly attenuated, and however, the Bayesian model could not accounted for the shifts. The results indicate that visual appearance can be modified by prediction based on the optimal acquisition of action-effect causal relation.

  14. Maternal and child undernutrition: effective action at national level.

    Bryce, Jennifer; Coitinho, Denise; Darnton-Hill, Ian; Pelletier, David; Pinstrup-Andersen, Per

    2008-02-01

    80% of the world's undernourished children live in just 20 countries. Intensified nutrition action in these countries can lead to achievement of the first Millennium Development Goal (MDG) and greatly increase the chances of achieving goals for child and maternal mortality (MDGs 4 and 5). Despite isolated successes in specific countries or for interventions--eg, iodised salt and vitamin A supplementation--most countries with high rates of undernutrition are failing to reach undernourished mothers and children with effective interventions supported by appropriate policies. This paper reports on an assessment of actions addressing undernutrition in the countries with the highest burden of undernutrition, drawing on systematic reviews and best-practice reports. Seven key challenges for addressing undernutrition at national level are defined and reported on: getting nutrition on the list of priorities, and keeping it there; doing the right things; not doing the wrong things; acting at scale; reaching those in need; data-based decisionmaking; and building strategic and operational capacity. Interventions with proven effectiveness that are selected by countries should be rapidly implemented at scale. The period from pregnancy to 24 months of age is a crucial window of opportunity for reducing undernutrition and its adverse effects. Programme efforts, as well as monitoring and assessment, should focus on this segment of the continuum of care. Nutrition resources should not be used to support actions unlikely to be effective in the context of country or local realities. Nutrition resources should not be used to support actions that have not been proven to have a direct effect on undernutrition, such as stand-alone growth monitoring or school feeding programmes. In addition to health and nutrition interventions, economic and social policies addressing poverty, trade, and agriculture that have been associated with rapid improvements in nutritional status should be

  15. Regular effective action of gauge field theory and quantum gravity

    Baaklini, N.S.

    1987-05-15

    We present a perturbative formalism for the effective quantum action of a general Fermi-Bose field theory. We propose a unitary alternative to the conventional virtual ghost prescription for handling the functional integral of gauge fields, based on the functional space metric that is determined by the Dirac brackets of the canonical theory. A gauge-invariant Gaussian cutoff is introduced by extending the functional space metric into a regular counterpart. The regular one-loop contributions of a scalar field to the photon and the graviton self-energies are computed. The otherwise logarithmically divergent contributions are found, in our scheme, to be independent of cutoff.

  16. The effective action approach applied to nuclear chiral sigma model

    The nuclear chiral sigma model of nuclear matter is considered by means of the Cornwall-Jackiw-tomboulis (CTJ) effective action. The method provides a very general framework for investigating many important problems: chiral symmetry in nuclear medium, energy density of nuclear ground state, nuclear Schwinger-Dyson (SD) equations, etc. It is shown that the SD equations for sigma-omega mixing are actually not present in this formalism. For numerical computation purposes the Hartree-Fock (HF) approximation for ground state energy density is also presented. (author). 26 refs

  17. Effective action for the Regge processes in gravity

    Lipatov, L.N. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2011-05-15

    It is shown, that the effective action for the reggeized graviton interactions can be formulated in terms of the reggeon fields A{sup ++} and A{sup --} and the metric tensor g{sub {mu}}{sub {nu}} in such a way, that it is local in the rapidity space and has the property of general covariance. The corresponding effective currents j{sup -} and j{sup +} satisfy the Hamilton-Jacobi equation for a massless particle moving in the gravitational field. These currents are calculated explicitly for the shock wave-like fields and a variation principle for them is formulated. As an application, we reproduce the effective lagrangian for the multi-regge processes in gravity together with the graviton Regge trajectory in the leading logarithmic approximation with taking into account supersymmetric contributions. (orig.)

  18. Effective corrective actions to enhance operational safety of nuclear installations

    The safe operation of nuclear power plants around the world and the prevention of incidents in these installations remain key concerns for the nuclear community. In this connection the feedback of operating experience plays a major role: every nuclear plant operator needs to have a system in place to identify and feed back the lessons learned from operating experience and to implement effective corrective actions to prevent safety events from reoccurring. An effective operating experience programme also includes a proactive approach that is aimed at preventing the first-time occurrence of safety events. In April 2003, the IAEA issued the PROSPER guidelines for nuclear installations to strengthen and enhance their own operating experience process and for self-assessment on the effectiveness of the feedback process. Subsequently, in the course of the Operational Safety Review Teams missions conducted by the IAEA that focused on the operational safety practices of nuclear power plants, the IAEA enhanced the review of the operating experience in nuclear power plants by implementing a new module that is derived from these guidelines. In order to highlight the effective implementation of the operating experience programme and to provide practical assistance in this area, the IAEA organized workshops and conferences to discuss recent trends in operating experience. The IAEA also performed assistance and review missions at plants and corporate organizations. The IAEA is further developing advice and assistance on operating experience feedback programmes and is reporting on good practices. The present publication is the outcome of two years of coordinated effort involving the participation of experts of nuclear organizations in several Member States. It provides information and good practices for successfully establishing an effective corrective actions programme. This publication forms part of a series that develops the principles set forth in these guidelines

  19. Effective Action for Cosmological Scalar Fields at Finite Temperature

    Cheung, Yeuk-Kwan E; Kang, Jin U; Kim, Jong Chol

    2015-01-01

    Scalar fields appear in many theories beyond the Standard Model of particle physics. In the early universe, they are exposed to extreme conditions, including high temperature and rapid cosmic expansion. Understanding their behavior in this environment is crucial to understand the implications for cosmology. We calculate the finite temperature effective action for the field expectation value in two particularly important cases, for damped oscillations near the ground state and for scalar fields with a flat potential. We find that the behavior in both cases can in good approximation be described by a complex valued effective potential that yields Markovian equations of motion. Near the potential minimum, we recover the solution to the well-known Langevin equation. For large field values we find a very different behavior, and our result for the damping coefficient significantly differs from the expressions given in the literature. We illustrate our results in a simple scalar model, for which we give analytic app...

  20. Nonlinear N=2 supersymmetry, effective actions and moduli stabilization

    Antoniadis, I. [Department of Physics, CERN - Theory Division, CH-1211 Geneva 23 (Switzerland); Centre de Physique Theorique, UMR du CNRS 7644, Ecole Polytechnique, 91128 Palaiseau (France); Derendinger, J.-P. [Physics Institute, Neuchatel University, Breguet 1, CH-2000 Neuchatel (Switzerland); Maillard, T. [Centre de Physique Theorique, UMR du CNRS 7644, Ecole Polytechnique, 91128 Palaiseau (France)], E-mail: maillard@cpht.polytechnique.fr

    2009-02-11

    Nonlinear supersymmetry is used to compute the general form of the effective D-brane action in type I string theory compactified to four dimensions in the presence of internal magnetic fields. In particular, the scalar potential receives three contributions: (1) a nonlinear part of the D-auxiliary component, associated to the Dirac-Born-Infeld action; (2) a Fayet-Iliopoulos (FI) D-term with a moduli-dependent coefficient; (3) a D-auxiliary independent (but moduli dependent) piece from the D-brane tension. Minimization of this potential leads to three general classes of vacua with moduli stabilization: (i) supersymmetric vacua allowing in general FI terms to be cancelled by non-trivial vacuum expectation values (VEV's) of charged scalar fields; (ii) anti-de Sitter vacua of broken supersymmetry in the presence of a non-critical dilaton potential that can be tuned at arbitrarily weak string coupling; (iii) if the dilaton is fixed in a supersymmetric way by three-form fluxes and in the absence of charged scalar VEV's, one obtains non-supersymmetric vacua with positive vacuum energy.

  1. Dura’s Effect on Securities Class Actions

    Scotland M. Duncan

    2008-12-01

    Full Text Available On April 19, 2005, the United States Supreme Court rendered a unanimous decision in Dura Pharmaceuticals, Inc. v. Broudo, which had been described as “the most important securities case in a decade.” Simply put, the decision raises the pleading standard for Rule 10b-5 cases asserting fraud-onthe-market; instead of requiring a showing of ex ante losses, such as inflation at the time of purchase, Dura requires a showing of ex post losses, such as market decline resulting from a corrective disclosure. This paper assesses the decision’s practical implications by examining and empirically testing whether the Supreme Court’s enhanced pleading requirements have impacted the frequency and magnitude of post-Reform Act (PSLRA class action securities cases. Specifically, this paper examines Dura’s effect on the filing and settling of cases, as well as on settlement amount. In particular, the results suggest that Dura, ceteris paribus, has had a statistically significant impact on both the filing and settlement of class actions, suggesting a reduction in frivolous litigation.

  2. Effective action and vacuum expectations in nonlinear $\\sigma$ model

    Fayzullaev, B A

    2015-01-01

    The equations for effective action for nonlinear $\\sigma$ model are derived using DeWitt method in two forms - for generator of vertex parts $\\Gamma$ and for generator of weakly connected parts $W$. Loop-expansion solutions to these equations are found. It is shown that vacuum expectation values for various quantities including divergence of a N\\"{o}ther current, trace of the energy-momentum tensor and so on, can be calculated by this method. Also it is shown that vacuum expectation to the sigma-field is determined by an explicit combination of tree Green function and classical solution. It is shown that the limit when coupling constant tends to zero is singular one.

  3. Covariant computation of effective actions in Horava-Lifshitz gravity

    D'Odorico, Giulio; Saueressig, Frank

    2015-01-01

    We initiate the systematic computation of the heat-kernel coefficients for Laplacian operators obeying anisotropic dispersion relations in curved spacetime. Our results correctly reproduce the limit where isotropy is restored and special anisotropic cases considered previously in the literature. Subsequently, the heat kernel is used to derive the scalar-induced one-loop effective action and beta functions of Horava-Lifshitz gravity. We identify the Gaussian fixed point which is supposed to provide the UV completion of the theory. In the present setting, this fixed point acts as an infrared attractor for the renormalization group flow of Newton's constant and the high-energy phase of the theory is screened by a Landau pole. We comment on the consequences of these findings for the renormalizability of the theory.

  4. [NKT cells: their development, mechanisms and effects of action].

    Bojarska-Junak, Agnieszka; Tabarkiewicz, Jacek; Roliński, Jacek

    2013-01-01

    NKT cells are a heterogeneous subset of T lymphocytes that share surface markers and functional characteristics with both conventional T lymphocytes and natural killer cells. Most NKT cells express a semi-invariant T cell receptor that reacts with glycolipid antigens presented by the CD1d molecule on the surface of antigen-presenting cells. NKT cells can modulate the immune response against infectious agents, autoantigens, tumors, tissue grafts and allergens. NKT cells mediate the activities through their ability to express pro- and anti-inflammatory cytokines that influence the type and magnitude of the immune response. The manuscript summarizes current views on development of NKT cells as well as mechanisms and effects of their action.  PMID:23475484

  5. Mephedrone: Public health risk, mechanisms of action, and behavioral effects.

    Dybdal-Hargreaves, Nicholas F; Holder, Nicholas D; Ottoson, Paige E; Sweeney, Melanie D; Williams, Tyisha

    2013-08-15

    The recent shortage of 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) has led to an increased demand for alternative amphetamine-like drugs such as the synthetic cathinone, 4-methylmethcathinone (mephedrone). Despite the re-classification of mephedrone as a Class B restricted substance by the United Kingdom and restrictive legislation by the United States, international policy regarding mephedrone control is still developing and interest in synthetic amphetamine-like drugs could drive the development of future mephedrone analogues. Currently, there is little literature investigating the mechanism of action and long-term effects of mephedrone. As such, we reviewed the current understanding of amphetamines, cathinones, and cocaine emphasizing the potentially translational aspects to mephedrone, as well as contrasting with the work that has been done specifically on mephedrone in order to present the current state of understanding of mephedrone in terms of its risks, mechanisms, and behavioral effects. Emerging research suggests that while there are structural and behavioral similarities of mephedrone with amphetamine-like compounds, it appears that serotonergic signaling may mediate more of mephedrone's effects unlike the more dopaminergic dependent effects observed in traditional amphetamine-like compounds. As new designer drugs are produced, current and continuing research on mephedrone and other synthetic cathinones should help inform policymakers' decisions regarding the regulation of novel 'legal highs.' PMID:23764466

  6. Self-action effects in semiconductor quantum dots

    Dneprovskii, V. S.; Kanev, A. R.; Kozlova, M. V.; Smirnov, A. M.

    2014-05-01

    Two-dimensional (2D) dynamic photonic crystal regime has been utilized to investigate self-diffraction effect and nonlinear optical properties of excitons in CdSe/ZnS colloidal quantum dots (QDs). Self-diffraction at 2D photonic crystal arises for three intersecting beams of Nd+3:YAG laser second harmonic in the case of one-photon resonant excitation of the exciton (electron - hole) transition QDs. The relaxation time of excited excitons has been measured by pump and probe technique at induced one-dimensional transient diffraction grating. Two-exponential decay with initial fast and slow parts was discovered. Self-action effect has been discovered in the case of stationary resonant excitation of excitons in CdSe/ZnS QDs by the beam of second harmonic of powerful 12-nanosecond laser pulses. The bleaching of exciton absorption and the creation of transparency channel (this effect provokes self-diffraction of the second harmonic beam) was explained by the dominating coexisting and competing processes of state filling in stationary excited quantum dots and Stark-shift of exciton spectral band. The peculiarities of the influence of these processes at the change of exciton absorption in quantum dots in the case of different detuning from exciton resonance (quantum dots with different size have been used) was analyzed.

  7. Actions for adoption of effective dose equivalent standards

    Regulations related with radiological protection have been revised to adopt SI units and to accept the ICRP recommendation requesting to use the effective dose equivalent for radiation exposure control. The present report mainly deals with actions to be taken in the field of radiation instrumentation to promote the adoption of effective dose equivalent standards. In the past, exposure in roentgen has been generally used as a quantity to represent the intensity of a X-ray or alpha-ray field, because it can be measured relatively easily and accurately. The introduction of the effective dose equivalent is intended to establish annual exposure limits to ensure that the possibility of death of workers in a radioactive environment and that of development of hereditary disorders in their children or grandchildren will be maintained below permissible levels. The quantity is expressed as the sum of each organ's dose equivalent multiplied by a weight that reflects risks. Presently, such weights are assigned to seven organs including the gential glands and red marrow. Fixed-type area monitors and portable survey meters are used for work environment monitoring while film badges, TLDs, dosimeters, etc., are employed for personnel monitoring. (Nogami, K.)

  8. On the effects of action on visual perception & How new movement types are learned

    Beets, Iseult Anna Maria

    2010-01-01

    Perception can induce effects on action. Perception of others´ actions can thus influence our own actions. However, research on how action can shape perception is sparse. In this thesis, the effects of (i) motor learning and (ii) simple movements, can influence visual perception. Furthermore, the issue of motor learning is addressed; how can new movement types be learned and do active and passively guided motor training lead to ...

  9. The Geometry of Quantum Hall Effect: An Effective Action for all Dimensions

    Karabali, Dimitra; Nair, V. P.

    2016-01-01

    We present a general formula for the topological part of the effective action for quantum Hall systems in higher dimensions, including fluctuations of the gauge field and metric around background fields of a specified topological class. The result is based on a procedure of integrating up from the Dolbeault index density which applies for the degeneracies of Landau levels, combined with some input from the standard descent procedure for anomalies. Features of the topological action in (2+1), ...

  10. Ecological effects of contaminants and remedial actions in Bear Creek

    Southworth, G.R.; Loar, J.M.; Ryon, M.G.; Smith, J.G.; Stewart, A.J. (Oak Ridge National Lab., TN (United States)); Burris, J.A. (C. E. Environmental, Inc., Tallahassee, FL (United States))

    1992-01-01

    Ecological studies of the Bear Creek watershed, which drains the area surrounding several Oak Ridge Y-12 Plant waste disposal facilities, were initiated in May 1984 and are continuing at present. These studies consisted of an initial, detailed characterization of the benthic invertebrate and fish communities in Bear Creek, and they were followed by a presently ongoing monitoring phase that involves reduced sampling intensities. The characterization phase utilized two approaches: (1) instream sampling of benthic invertebrate and fish communities in Bear Creek to identify spatial and temporal patterns in distribution and abundance and (2) laboratory bioassays on water samples from Bear Creek and selected tributaries to identify potential sources of toxicity to biota. The monitoring phase of the ecological program relates to the long-term goals of identifying and prioritizing contaminant sources and assessing the effectiveness of remedial actions. It continues activities of the characterization phase at less frequent intervals. The Bear Greek Valley is a watershed that drains the area surrounding several closed Oak Ridge Y-12 Plant waste disposal facilities. Past waste disposal practices in Bear Creek Valley resulted in contamination of Bear Creek and consequent ecological damage. Extensive remedial actions have been proposed at waste sites, and some of the have been implemented or are now underway. The proposed study plan consists of an initial, detailed characterization of the benthic invertebrate and fish communities in Bear Creek in the first year followed by a reduction in sampling intensity during the monitoring phase of the plan. The results of sampling conducted from May 1984 through early 1989 are presented in this report.

  11. Scales, strategies and actions for effective energy planning: A review

    This paper is a review of the most recent literature on the interaction between climate change, land-use and energy, based on the analysis of papers collected through the most relevant scientific literature databases. A total of 114 papers published between 2000 and 2011 were reviewed. The aims of this review are: in general (1) to identify the different research topics that have been developed related to the interaction between climate change, land-use and energy; more specifically, (2) to analyze what are the most suitable spatial and temporal scales of investigation to focus on for actions and strategies to reduce critical issues in the field of energy and environment; (3) to identify which actions and strategies are deemed as the most appropriate to mitigate critical issues in energy and environment; and given the research gaps found in the review, (4) to propose research recommendations in the context of effective climate-energy planning. We argue that there are certain gaps and needs for a “nested” environmental governance. It is necessary to understand how different environmental policies overlap and how they can be integrated in order to verify whether there are conflicting targets that may negate each other in the long term. - Highlights: • Energy production and consumption can directly or indirectly affect climate change. • Energy sector is influenced directly and indirectly by changes in climate conditions. • Energy sector and climate change affect and limit alternative uses of land, causing land-use changes. • The most suitable spatial scale for energy planning is the municipal level requiring short-term perspectives. • Several research recommendations to deal with the complexity of energy-land-use-climate change issue are proposed

  12. Ecological effects of contaminants and remedial actions in Bear Creek

    Ecological studies of the Bear Creek watershed, which drains the area surrounding several Oak Ridge Y-12 Plant waste disposal facilities, were initiated in May 1984 and are continuing at present. These studies consisted of an initial, detailed characterization of the benthic invertebrate and fish communities in Bear Creek, and they were followed by a presently ongoing monitoring phase that involves reduced sampling intensities. The characterization phase utilized two approaches: (1) instream sampling of benthic invertebrate and fish communities in Bear Creek to identify spatial and temporal patterns in distribution and abundance and (2) laboratory bioassays on water samples from Bear Creek and selected tributaries to identify potential sources of toxicity to biota. The monitoring phase of the ecological program relates to the long-term goals of identifying and prioritizing contaminant sources and assessing the effectiveness of remedial actions. It continues activities of the characterization phase at less frequent intervals. The Bear Greek Valley is a watershed that drains the area surrounding several closed Oak Ridge Y-12 Plant waste disposal facilities. Past waste disposal practices in Bear Creek Valley resulted in contamination of Bear Creek and consequent ecological damage. Extensive remedial actions have been proposed at waste sites, and some of the have been implemented or are now underway. The proposed study plan consists of an initial, detailed characterization of the benthic invertebrate and fish communities in Bear Creek in the first year followed by a reduction in sampling intensity during the monitoring phase of the plan. The results of sampling conducted from May 1984 through early 1989 are presented in this report

  13. Effects and Mechanism of Action of a Tribulus terrestris Extract on Penile Erection

    Do, Jungmo; Choi, Seemin; Choi, Jaehwi; Hyun, Jae Seog

    2013-01-01

    Purpose Tribulus terrestris has been used as an aphrodisiac. However, little is known about the effects and mechanism of action of T. terrestris on penile erection. Therefore, the effect of a T. terrestris extract and the mechanism of action of the extract on relaxation of the corpus cavernosum (CC) were investigated. The erectogenic effects of an oral preparation of the extract were also assessed. Materials and Methods The relaxation effects and mechanism of action of the T. terrestris extra...

  14. Regulation of international energy markets: Economic effects of political actions

    Shcherbakova, Anastasia V.

    Recent increases in volatility of energy prices have led many governments to reevaluate their regard of national energy reserves and reconsider future exploration, production, and consumption patterns. The flurry of activity that has been generated by such price volatility has included large-scale nationalizations of energy sectors, unilateral renegotiations of foreign energy development contracts, and expropriations of resources from foreign energy firms on one hand, and on the other hand more rapid energy sector liberalization, intensified search for and development of renewable fuels and technologies, and development of incentives for increased energy efficiency and conservation. The aim of this dissertation is to examine and quantify the extent of positive and negative effects that have resulted from some of these activities. The first chapter focuses on quantifying the effect that nationalistic sentiment has had on economic attractiveness of energy sectors during the decade prior to the recent global economic crisis, as measured by foreign direct investment (FDI) inflows. Empirical results demonstrate that both political and economic conditions play an important role in investors' decisions. A combination of investment friendliness, corruption levels, and democracy all help to explain the trends in energy-sector investment levels over time in my sample countries, although differences in the types of corruption existing in these nations do not. Investment levels, in turn, appear to influence future levels of oil production, underscoring the significance of good investment policies for future success of energy sectors. Chapter two considers the response of energy stock prices to severe regulatory actions. It employs an event study framework to examine causal effects of critical informational announcements (i.e. events of expropriation and nationalization) on daily returns and cumulative losses in firm value of energy corporations. Results show that a firm

  15. Effects of action video game training on visual working memory.

    Blacker, Kara J; Curby, Kim M; Klobusicky, Elizabeth; Chein, Jason M

    2014-10-01

    The ability to hold visual information in mind over a brief delay is critical for acquiring information and navigating a complex visual world. Despite the ubiquitous nature of visual working memory (VWM) in our everyday lives, this system is fundamentally limited in capacity. Therefore, the potential to improve VWM through training is a growing area of research. An emerging body of literature suggests that extensive experience playing action video games yields a myriad of perceptual and attentional benefits. Several lines of converging work suggest that action video game play may influence VWM as well. The current study utilized a training paradigm to examine whether action video games cause improvements to the quantity and/or the quality of information stored in VWM. The results suggest that VWM capacity, as measured by a change detection task, is increased after action video game training, as compared with training on a control game, and that some improvement to VWM precision occurs with action game training as well. However, these findings do not appear to extend to a complex span measure of VWM, which is often thought to tap into higher-order executive skills. The VWM improvements seen in individuals trained on an action video game cannot be accounted for by differences in motivation or engagement, differential expectations, or baseline differences in demographics as compared with the control group used. In sum, action video game training represents a potentially unique and engaging platform by which this severely capacity-limited VWM system might be enhanced. PMID:25068696

  16. Polyphenols: Extraction Methods, Antioxidative Action, Bioavailability and Anticarcinogenic Effects.

    Brglez Mojzer, Eva; Knez Hrnčič, Maša; Škerget, Mojca; Knez, Željko; Bren, Urban

    2016-01-01

    Being secondary plant metabolites, polyphenols represent a large and diverse group of substances abundantly present in a majority of fruits, herbs and vegetables. The current contribution is focused on their bioavailability, antioxidative and anticarcinogenic properties. An overview of extraction methods is also given, with supercritical fluid extraction highlighted as a promising eco-friendly alternative providing exceptional separation and protection from degradation of unstable polyphenols. The protective role of polyphenols against reactive oxygen and nitrogen species, UV light, plant pathogens, parasites and predators results in several beneficial biological activities giving rise to prophylaxis or possibly even to a cure for several prevailing human diseases, especially various cancer types. Omnipresence, specificity of the response and the absence of or low toxicity are crucial advantages of polyphenols as anticancer agents. The main problem represents their low bioavailability and rapid metabolism. One of the promising solutions lies in nanoformulation of polyphenols that prevents their degradation and thus enables significantly higher concentrations to reach the target cells. Another, more practiced, solution is the use of mixtures of various polyphenols that bring synergistic effects, resulting in lowering of the required therapeutic dose and in multitargeted action. The combination of polyphenols with existing drugs and therapies also shows promising results and significantly reduces their toxicity. PMID:27409600

  17. Effect of Composite Action on the Strength of Wood Roofs

    Ivan A. Campos Varela

    2015-01-01

    Full Text Available Engineering certification for the installation of solar photovoltaic modules on wood roofs is often denied because existing wood roofs do not meet current building codes. Rather than requiring expensive structural retrofits, we desire to show that many roofs are actually sufficiently strong if the effect of composite action produced by joist-sheathing interaction is considered. In a series of laboratory experiments using a limited number of two-by-four wood joists with and without sheathing panels, conventionally sheathed stud-grade joists, surprisingly, exhibited between 18% and 63% higher nominal strength than similar bare joists. To explain this strength increase, a simple model was developed to predict the strengths of the nailed partially composite sections, but the model only justifies a 1.4% to 3.8% increase in bending strength of joists with an allowable bending strength of 1000 psi. More testing is indicated to resolve this discrepancy between laboratory results and analytical modeling results. In addition to elucidating nonlinear partial composite behavior of existing roof systems, this paper shows that, with minor changes in roof framing practices, strength increases of 70% or more are achievable, compared to the strengths of conventionally sheathed joists.

  18. On compatibility of string effective action with an accelerating universe

    Neupane, Ishwaree P [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Central Department of Physics, Tribhuvan University, Kirtipur, Kathmandu (Nepal)

    2006-12-21

    In this paper, we fully investigate the cosmological effects of the moduli-dependent one-loop corrections to the gravitational couplings of the string effective action to explain the cosmic acceleration problem in the early (and/or late) universe. These corrections comprise a Gauss-Bonnet (GB) invariant multiplied by universal non-trivial functions of the common modulus {sigma} and the dilaton {phi}. The model exhibits several features of cosmological interest, including the transition between deceleration and acceleration phases. By considering some phenomenologically motivated ansatze for one of the scalars and/or the scale factor (of the universe), we also construct a number of interesting inflationary potentials. In all examples under consideration, we find that the model leads only to a standard inflation (w {>=} -1) when the numerical coefficient {delta} associated with modulus-GB coupling is positive, while the model can also lead to a non-standard inflation (w < -1), if {delta} is negative. In the absence of (or trivial) coupling between the GB term and the scalars, there is no crossing between the w < -1 and w > -1 phases, while this is possible with non-trivial GB couplings, even for the constant dilaton phase of the standard picture. Within our model, after a sufficient amount of e-folds of expansion, the rolling of both fields {phi} and {sigma} can be small. In turn, any possible violation of equivalence principle or deviations from the standard general relativity may be small enough to easily satisfy all astrophysical and cosmological constraints.

  19. Renormalization-group flow of the effective action of cosmological large-scale structures

    Floerchinger, Stefan; Garny, Mathias; Tetradis, Nikolaos; Wiedemann, Urs Achim

    2016-01-01

    Following an approach of Matarrese and Pietroni, we derive the functional renormalization group (RG) flow of the effective action of cosmological large-scale structures. Perturbative solutions of this RG flow equation are shown to be consistent with standard cosmological perturbation theory. Non-perturbative approximate solutions can be obtained by truncating the a priori infinite set of possible effective actions to a finite subspace. Using for the truncated effective action a form dictated ...

  20. Experts see it all: configural effects in action observation

    Calvo-Merino, B.; Ehrenberg, S; Leung, D. M. H.; Haggard, P

    2010-01-01

    Biological motion perception is influenced by observers’ familiarity with the observed action. Here we used classical dance as a means to investigate how visual and motor experience modulates perceptual mechanism for configural processing of actions. While some ballet moves are performed by only one gender, male and female dancers train together and acquire visual knowledge of all ballet moves. 24 expert ballet dancers (12 female) and matched non-expert participants viewed pairs of upright an...

  1. The effects of an action video game on visual and affective information processing.

    Bailey, Kira; West, Robert

    2013-04-01

    Playing action video games can have beneficial effects on visuospatial cognition and negative effects on social information processing. However, these two effects have not been demonstrated in the same individuals in a single study. The current study used event-related brain potentials (ERPs) to examine the effects of playing an action or non-action video game on the processing of emotion in facial expression. The data revealed that 10h of playing an action or non-action video game had differential effects on the ERPs relative to a no-contact control group. Playing an action game resulted in two effects: one that reflected an increase in the amplitude of the ERPs following training over the right frontal and posterior regions that was similar for angry, happy, and neutral faces; and one that reflected a reduction in the allocation of attention to happy faces. In contrast, playing a non-action game resulted in changes in slow wave activity over the central-parietal and frontal regions that were greater for targets (i.e., angry and happy faces) than for non-targets (i.e., neutral faces). These data demonstrate that the contrasting effects of action video games on visuospatial and emotion processing occur in the same individuals following the same level of gaming experience. This observation leads to the suggestion that caution should be exercised when using action video games to modify visual processing, as this experience could also have unintended effects on emotion processing. PMID:23419898

  2. Geometry of the quantum Hall effect: An effective action for all dimensions

    Karabali, Dimitra; Nair, V. P.

    2016-07-01

    We present a general formula for the topological part of the effective action for integer quantum Hall systems in higher dimensions, including fluctuations of the gauge field and metric around background fields of a specified topological class. The result is based on a procedure of integrating up from the Dolbeault index density which applies for the degeneracies of Landau levels, combined with some input from the standard descent procedure for anomalies. Features of the topological action in (2 +1 ), (4 +1 ), (6 +1 ) dimensions, including the contribution due to gravitational anomalies, are discussed in some detail.

  3. The Geometry of Quantum Hall Effect: An Effective Action for all Dimensions

    Karabali, Dimitra

    2016-01-01

    We present a general formula for the topological part of the effective action for quantum Hall systems in higher dimensions, including fluctuations of the gauge field and metric around background fields of a specified topological class. The result is based on a procedure of integrating up from the Dolbeault index density which applies for the degeneracies of Landau levels, combined with some input from the standard descent procedure for anomalies. Features of the topological action in (2+1), (4+1), (6+1) dimensions, including the contribution due to gravitational anomalies, are discussed in some detail.

  4. Effective actions for F-theory compactifications and tensor theories

    In this thesis we study the low-energy effective dynamics emerging from a class of F-theory compactifications in four and six dimensions. We also investigate six-dimensional supersymmetric quantum field theories with self-dual tensors, motivated by the problem of describing the long-wavelength regime of a stack of M5-branes in M-theory. These setups share interesting common features. They both constitute examples of intrinsically non-perturbative physics. On the one hand, in the context of F-theory the non-perturbative character is encoded in the geometric formulation of this class of string vacua, which allows the complexified string coupling to vary in space. On the other hand, the dynamics of a stack of multiple M5-branes flows in the infrared to a novel kind of superconformal field theories in six dimensions - commonly referred to as (2,0) theories - that are expected to possess no perturbative weakly coupled regime and have resisted a complete understanding so far. In particular, no Lagrangian description is known for these models. The strategy we employ to address these two problems is also analogous. A recurring Leitmotif of our work is a transdimensional treatment of the system under examination: in order to extract information about dynamics in d dimensions we consider a (d-1)-dimensional setup. As far as F-theory compactifications are concerned, this is a consequence of the duality between M-theory and F-theory, which constitutes our main tool in the derivation of the effective action of F-theory compactifications. We apply it to six-dimensional F-theory vacua, obtained by taking the internal space to be an elliptically fibered Calabi-Yau threefold, but we also employ it to explore a novel kind of F-theory constructions in four dimensions based on manifolds with Spin(7) holonomy. With reference to six-dimensional (2,0) theories, the transdimensional character of our approach relies in the idea of studying these theories in five dimensions. Indeed, we

  5. Interactions between sentence comprehension and concurrent action: The role of movement effects and timing

    Diefenbach, C

    2010-01-01

    Embodied approaches to language comprehension suggest that we understand sentences by using our perception and action systems for simulating their contents. In line with this assumption, the action-sentence compatibility effect (ACE) shows that sensibility judgments for sentences are faster when the direction of the described action matches the direction of the response movement. The aim of this thesis was to investigate whether this compatibility is effective between sentence direction and m...

  6. Effects of context on visuomotor interference depends on the perspective of observed actions.

    Marta Bortoletto

    Full Text Available Visuomotor interference occurs when the execution of an action is facilitated by the concurrent observation of the same action and hindered by the concurrent observation of a different action. There is evidence that visuomotor interference can be modulated top-down by higher cognitive functions, depending on whether own performed actions or observed actions are selectively attended. Here, we studied whether these effects of cognitive context on visuomotor interference are also dependent on the point-of-view of the observed action. We employed a delayed go/no-go task known to induce visuomotor interference. Static images of hand gestures in either egocentric or allocentric perspective were presented as "go" stimuli after participants were pre-cued to prepare either a matching (congruent or non-matching (incongruent action. Participants performed this task in two different cognitive contexts: In one, they focused on the visual image of the hand gesture shown as the go stimulus (image context, whereas in the other they focused on the hand gesture they performed (action context. We analyzed reaction times to initiate the prepared action upon presentation of the gesture image and found evidence of visuomotor interference in both contexts and for both perspectives. Strikingly, results show that the effect of cognitive context on visuomotor interference also depends on the perspective of observed actions. When focusing on own-actions, visuomotor interference was significantly less for gesture images in allocentric perspective than in egocentric perspective; when focusing on observed actions, visuomotor interference was present regardless of the perspective of the gesture image. Overall these data suggest that visuomotor interference may be modulated by higher cognitive processes, so that when we are specifically attending to our own actions, images depicting others' actions (allocentric perspective have much less interference on our own actions.

  7. Comment on ``Functional integral for Weyl fermions and the effective action''

    Banerjee, R.; Banerjee, H.

    1989-02-01

    Baaklini's method of obtaining the effective action for Weyl fermions is shown to yield either a gauge-invariant or a gauge-variant form depending on the specific definition employed in the analysis. The structures of the effective action proposed by Baaklini are found to correspond to the standard expressions.

  8. Conformally covariant operators and the effective action in an external gravitational field

    The n-dimensional expressions for the second-order conformally covariant differential operators acting on vector and tensor fields and for the fourth-order conformally covariant operator acting on scalar fields are obtained. For the fourth-order operator one-loop effective action is evaluated in four dimensions. The possibility of effective action evaluation for other conformally covariant operators is discussed

  9. The Effect of Timing on Gliclazide Absorption and Action

    Ishibashi, Fukashi; Takashina, Seiryo

    1990-01-01

    In this study we tried to determine when in relation to meals gliclazide should be taken for optimum hypoglycemic action. Eight non-insulin-dependent diabetics participated in this study during hospitalization for glycemic control.   After stabilization of glycemic control on gliclazide, they took a 40 mg tablet of gliclazide either 30 minutes before, immediately before, or immediately after breakfast on 3 consecutive days. We then determined serum gliclazide, glucose and IRI levels at 30...

  10. On the effective character of a non abelian DBI action

    Osorio, M A R; Suárez, María

    2001-01-01

    We study the way Lorentz covariance can be reconstructed from Matrix Theory as a IMF description of M-theory. The problem is actually related to the interplay between a non abelian Dirac-Born-Infeld action and Super-Yang-Mills as its generalized non-relativistic approximation. All this physics shows up by means of an analysis of the asymptotic expansion of the Bessel functions $K_\

  11. The Side-Effect Effect in Children Is Robust and Not Specific to the Moral Status of Action Effects

    Rakoczy, Hannes; Behne, Tanya; Clüver, Annette; Dallmann, Stephanie; Weidner, Sarah; Waldmann, Michael R.

    2015-01-01

    Adults’ intentionality judgments regarding an action are influenced by their moral evaluation of this action. This is clearly indicated in the so-called side-effect effect: when told about an action (e.g. implementing a business plan) with an intended primary effect (e.g. raise profits) and a foreseen side effect (e.g. harming/helping the environment), subjects tend to interpret the bringing about of the side effect more often as intentional when it is negative (harming the environment) than when it is positive (helping the environment). From a cognitive point of view, it is unclear whether the side-effect effect is driven by the moral status of the side effects specifically, or rather more generally by its normative status. And from a developmental point of view, little is known about the ontogenetic origins of the effect. The present study therefore explored the cognitive foundations and the ontogenetic origins of the side-effect effect by testing 4-to 5-year-old children with scenarios in which a side effect was in accordance with/violated a norm. Crucially, the status of the norm was varied to be conventional or moral. Children rated the bringing about of side-effects as more intentional when it broke a norm than when it accorded with a norm irrespective of the type of norm. The side-effect effect is thus an early-developing, more general and pervasive phenomenon, not restricted to morally relevant side effects. PMID:26218422

  12. Numerical simulation of antiarrhythmic drugs effects on cardiac action potential

    Převorovská, Světlana; Maršík, František

    Brno : Brno University of Technology, 2006 - (Burša, J.; Fuis, V.), s. 170-171 ISBN 80-214-3232-2. [ Human Biomechanics 2006. Hrotovice (CZ), 13.11.2006-16.11.2006] R&D Projects: GA ČR(CZ) GA106/03/1073; GA ČR(CZ) GA106/03/0958 Institutional research plan: CEZ:AV0Z20760514 Keywords : human cardiovascular system * cardiac action potential * antiarrhytmmic drugs-cell channel interaction Subject RIV: BK - Fluid Dynamics

  13. 10D massive type IIA supergravities as the uplift of parabolic M2-brane torus bundles

    Garcia del Moral, Maria Pilar [Universidad de Antofagasta (Chile). Dept. de Fisica; Restuccia, Alvaro [Universidad de Antofagasta (Chile). Dept. de Fisica; Universidad Simon Bolivar, Caracas (Venezuela, Bolivarian Republic of). Dept. de Fisica

    2016-04-15

    We remark that the two 10D massive deformations of the N = 2 maximal type IIA supergravity (Romans and HLW supergravity) are associated to the low energy limit of the uplift to 10D of M2-brane torus bundles with parabolic monodromy linearly and non-linearly realized respectively. Romans supergravity corresponds to M2-brane compactified on a twice-punctured torus bundle. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. More evidence for a refined Gribov-Zwanziger action based on an effective potential approach

    Vandersickel, N.; Dudal, D.; Sorella, S.P.

    2011-01-01

    The purpose of this proceeding is twofold. Firstly, we shall make the refining of the Gribov-Zwanziger action more complete by taking into account more condensates than considered so far. Secondly, we shall provide more evidence for the refined Gribov-Zwanziger action based on an effective potential approach.

  15. In-Out Formalism for One-Loop Effective Actions in QED and Gravity

    Kim, Sang Pyo

    2016-01-01

    The in-out formalism is a systematic and powerful method for finding the effective actions in an electromagnetic field and a curved spacetime provided that the field equation has explicitly known solutions. The effective action becomes complex when pairs of charged particles are produced due to an electric field and curved spacetime. This may lead to a conjecture of one-to-one correspondence between the vacuum polarization (real part) and the vacuum persistence (imaginary part). We illustrate the one-loop effective action in a constant electric field in a Minkowski spacetime and in a uniform electric field in a two-dimensional (anti-) de sitter space.

  16. Scaling behaviour of the effective chiral action and stability of the chiral soliton

    The effective chiral action is evaluated within a novel improved heat-kernel expansion, which includes gradients of the chiral field in a non-perturbative way. The exact scaling behaviour of the effective action of a localized chiral field with respect to changing its spatial size is found. From this it is proved that the radiatively induced derivative terms cannot absolutely stabilize the chiral soliton against collapsing. The collapsing of the soliton is, however, accompanied by a vanishing of the baryon charge. It is argued that the effective chiral action constrained to a fixed baryon number may still admit stable soliton configurations. (orig.)

  17. System markets: Indirect network effects in action, or inaction?

    J.L.G. Binken (Jeroen)

    2010-01-01

    textabstractIn this dissertation, I empirically examine system markets up close. More specifically I examine indirect network effects, both demand-side and supply-side indirect network effects. Indirect network effects are the source of positive feedback in system markets, or so network effect theo

  18. Effective actions for the SU(2) confinement-deconfinement phase transition

    We compare different Polyakov-loop actions yielding effective descriptions of finite-temperature SU(2) Yang-Mills theory on the lattice. The actions are motivated by a simultaneous strong coupling and character expansion obeying center symmetry and include both Ising and Ginzburg-Landau type models. To keep things simple we limit ourselves to nearest-neighbor interactions. Some truncations involving the most relevant characters are studied within a novel mean-field approximation. Using inverse Monte Carlo techniques based on exact geometrical Schwinger-Dyson equations we determine the effective couplings of the Polyakov-loop actions. Monte Carlo simulations of these actions reveal that the mean-field analysis is a fairly good guide to the physics involved. Our Polyakov-loop actions reproduce standard Yang-Mills observables well up to limitations due to the nearest-neighbor approximation

  19. Action time effect of lime on its depressive ability for pyrite

    Tichang Sun

    2004-01-01

    Two sample groups of bulk concentrates consisting mainly of pyrite and chalcopyrite from Daye and Chenghchao Mines in Hubei Province of China were used to investigate the effect of the action time of lime on its depressive ability for pyrite. The experimental results conducted with different samples and collectors showed that the action time between lime and pyrite markedly influences the depressive ability of lime. The depressive ability of lime increased with the action time increasing. It was also proved that the depressive results obtained at a large lime dosage after a shorter action time are similar to those obtained at a small lime dosage after a longer action time. The increase of depressive ability of lime after a longer action time is because that there are different mechanisms in different action time. The composition on the surface of pyrite acted for different time with lime was studied by using ESCA (Electron Spectroscopic Chemical Analysis). The results showed that iron hydroxide and calcium sulphate formed on the pyrite surface at the presence of lime in the pulp but the amounts of iron hydroxide and calcium sulphate were different at different action time. At the beginning action time the compound formed on the pyrite surface was mainly calcium sulphate and almost no iron hydroxide formed; but with the action time increasing, iron hydroxide formed. The longer the action time, the more iron hydroxide and the less calcium sulphate formed. It was considered that the stronger depressive ability of lime after a longer action time is because more iron hydroxide forms on the pyrite surface.

  20. System markets: Indirect network effects in action, or inaction?

    Binken, Jeroen

    2010-01-01

    textabstractIn this dissertation, I empirically examine system markets up close. More specifically I examine indirect network effects, both demand-side and supply-side indirect network effects. Indirect network effects are the source of positive feedback in system markets, or so network effect theory tells us. Systems are composed of complementary and interdependent products, such as hardware and software. For instance, a video game system is composed of the video game console, on the one han...

  1. Characteristics of Effective Training: Developing a Model To Motivate Action.

    Wise, Dena; Ezell, Patsy

    2003-01-01

    The Parenting and Consumer Education project identified effective models for training welfare-to-work facilitators. Premises were the importance of process, learner responsibility, and improvement of social networks. Effective training was learner focused, inspiring, and motivating; demonstrated productive behaviors and effective life skills; and…

  2. Leadership: Improving Its Effectiveness. Research Action Brief Number 1.

    ERIC Clearinghouse on Educational Management, Eugene, OR.

    This brief summarizes the major findings of significant research studies dealing with different leadership behaviors and strategies for increasing leadership effectiveness. Fred Fiedler's Contingency Theory of Leadership Effectiveness emphasizes that a leader's effectiveness is determined by how well his leadership style fits the specific…

  3. Fight against the greenhouse effect. From the local to the international action

    In the fight against the greenhouse gases emissions, the local government are directly concerned. This sheet aims to explain the greenhouse effect, the kyoto protocol, the french national policy and to orientate the local actions. (A.L.B.)

  4. The generalized Schwinger-DeWitt technique and the unique effective action in quantum gravity

    The purpose of this talk is to discuss how one can define and compute the effective action. The authors consider the following subjects: 1. The parameterization-independent and gauge-independent definition of the effective action in QFT. 2. Extension of the Schwinger-DeWitt technique to nonminimal operators, higher-order operators and higher loop orders. The method of generating functional traces. 3. Summation of the proper-time series. Nonlocal terms in the effective action. 4. Applications. The complete algorithm for divergences of a fourth-order operator. The calculational technique for the unique effective action in gauge theories. The unique counterterms for Einstein's theory. Covariant calculation of divergences in two-loop graphs and the absence of leading divergences in two-loop quantum gravity

  5. A Conformal Fixed-Point Equation for the Effective Average Action

    Rosten, Oliver J

    2016-01-01

    A Legendre transform of the recently discovered conformal fixed-point equation is constructed, providing an unintegrated equation encoding full conformal invariance within the framework of the effective average action.

  6. T-duality in the string theory effective action with a string source

    Nurmagambetov, Alexei

    2001-01-01

    We consider the T-duality transformations of the low-energy quantum string theory effective action in the presence of classical fundamental string source and demonstrate explicitly that T-duality still holds.

  7. Mechanism and Effectiveness of Reduction Action of Unsaturated Polyester Resin Reducer

    2001-01-01

    The reduction action mechanism of unsaturated polyester resin reducer is analysed.The experimental results show that the active reducer bearing reactive functional group on the ends of molecules effectively lowers the curing shrinkage of unvaturated polyester resin.

  8. The four-loop string effective action from the bosonic σ-model

    We discuss the formulation of the string effective action, in terms of quantities defined within the bosonic σ-model, at four loops or O(α'4). In particular we show that a recent construction given by Osborn correctly yields the effective action at this order for the minimal subtraction renormalisation scheme. We demonstrate a renormalisation scheme for which Osborn's action reduces to a simpler form proposed by Tseytlin at this order. As part of our analysis, we calculate, using indirect methods, various O(α'4) quantities for the σ-model, in particular the five-loop dilaton β-function. (orig.)

  9. The Quantum Consistency of the Ten-Dimensional Heterotic String Effective Action

    Simon Davis

    2011-01-01

    The finiteness of superstring theory at each order in perturbation theory is considered with respect to the ten-dimensional effective action. The quantum consistency of the ten-dimensional superstring effective action is confirmed with an analysis of the perturbative expansion of the quartic sector. It is found to be compatible with the finiteness of reduced four-dimensional theory. Furthermore, implications for the validity of superstring perturbation theory at lower energies is considered.

  10. Effect of Action Verbs on the Performance of a Complex Movement

    Rabahi, Tahar; Fargier, Patrick; Rifai Sarraj, Ahmad; Clouzeau, Cyril; Massarelli, Raphael

    2013-01-01

    The interaction between language and motor action has been approached by studying the effect of action verbs, kinaesthetic imagery and mental subtraction upon the performance of a complex movement, the squat vertical jump (SVJ). The time of flight gave the value of the height of the SVJ and was measured with an Optojump® and a Myotest® apparatuses. The results obtained by the effects of the cognitive stimuli showed a statistically significant improvement of the SVJ performance after either lo...

  11. Effect of action verbs on the performance of a complex movement.

    Tahar Rabahi

    Full Text Available The interaction between language and motor action has been approached by studying the effect of action verbs, kinaesthetic imagery and mental subtraction upon the performance of a complex movement, the squat vertical jump (SVJ. The time of flight gave the value of the height of the SVJ and was measured with an Optojump® and a Myotest® apparatuses. The results obtained by the effects of the cognitive stimuli showed a statistically significant improvement of the SVJ performance after either loudly or silently pronouncing, hearing or reading the verb saute (jump in French language. Action verbs specific for other motor actions (pince = pinch, lèche = lick or non-specific (bouge = move showed no or little effect. A meaningless verb for the French subjects (tiáo = jump in Chinese showed no effect as did rêve (dream, tombe (fall and stop. The verb gagne (win improved significantly the SVJ height, as did its antonym perds (lose suggesting a possible influence of affects in the subjects' performance. The effect of the specific action verb jump upon the heights of SVJ was similar to that obtained after kinaesthetic imagery and after mental subtraction of two digits numbers from three digits ones; possibly, in the latter, because of the intervention of language in calculus. It appears that the effects of the specific action verb jump did seem effective but not totally exclusive for the enhancement of the SVJ performance. The results imply an interaction among language and motor brain areas in the performance of a complex movement resulting in a clear specificity of the corresponding action verb. The effect upon performance may probably be influenced by the subjects' intention, increased attention and emotion produced by cognitive stimuli among which action verbs.

  12. Effect of action verbs on the performance of a complex movement.

    Rabahi, Tahar; Fargier, Patrick; Rifai Sarraj, Ahmad; Clouzeau, Cyril; Massarelli, Raphael

    2013-01-01

    The interaction between language and motor action has been approached by studying the effect of action verbs, kinaesthetic imagery and mental subtraction upon the performance of a complex movement, the squat vertical jump (SVJ). The time of flight gave the value of the height of the SVJ and was measured with an Optojump® and a Myotest® apparatuses. The results obtained by the effects of the cognitive stimuli showed a statistically significant improvement of the SVJ performance after either loudly or silently pronouncing, hearing or reading the verb saute (jump in French language). Action verbs specific for other motor actions (pince = pinch, lèche = lick) or non-specific (bouge = move) showed no or little effect. A meaningless verb for the French subjects (tiáo = jump in Chinese) showed no effect as did rêve (dream), tombe (fall) and stop. The verb gagne (win) improved significantly the SVJ height, as did its antonym perds (lose) suggesting a possible influence of affects in the subjects' performance. The effect of the specific action verb jump upon the heights of SVJ was similar to that obtained after kinaesthetic imagery and after mental subtraction of two digits numbers from three digits ones; possibly, in the latter, because of the intervention of language in calculus. It appears that the effects of the specific action verb jump did seem effective but not totally exclusive for the enhancement of the SVJ performance. The results imply an interaction among language and motor brain areas in the performance of a complex movement resulting in a clear specificity of the corresponding action verb. The effect upon performance may probably be influenced by the subjects' intention, increased attention and emotion produced by cognitive stimuli among which action verbs. PMID:23844233

  13. The effect of action recognition and robot awareness in cooperative robot teams

    Parker, L.E.

    1995-03-01

    Previous research in cooperative robotics has investigated several possible ways of coordinating the actions of cooperative teams -- from implicit cooperation through sensory feedback to explicit cooperation using the exchange of communicated messages. These various approaches differ in the extent to which robot team members arc aware of, or recognize, the actions of their teammates, and the extent to which they use this information to effect their own actions. The research described in this paper investigates this issue of robot awareness of team member actions and its effect on cooperative team performance by examining the results of a series of experiments on teams of physical mobile robots performing a laboratory version of hazardous waste cleanup. In these experiments. we vary the team size (and thus the level of redundancy in team member capabilities) and the level of awareness robots have of their teammates` current actions and evaluate the team`s performance using two metrics: time and energy. The results indicate that the impact of action awareness on cooperative team performance is a function not only of team size and the metric of evaluation. but also on the degree to which the effects of actions can be sensed through the world, the relative amount of work that is available per robot, and the cost of replicated actions. From these empirical studies, we propose a number of principles regarding the use of action recognition and robot awareness of team member actions in cooperative teams -- principles which will help guide engineers in the design and composition of the proper cooperative team for a given robotic mission.

  14. The effects of familiarity on thought--action fusion.

    Berman, Noah C; Wheaton, Michael G; Fabricant, Laura E; Jacobson, Spenser R; Abramowitz, Jonathan S

    2011-10-01

    The present study examined whether beliefs about the importance of thoughts (i.e., thought--action fusion; TAF) are related to the target subject of the negative thought. One hundred and seven undergraduate students were randomly assigned to imagine either a beloved relative or a stranger being diagnosed with cancer and provided in vivo ratings of anxiety, likelihood, moral wrongness, urge to neutralize, and how upsetting the event would be if it occurred. Results indicated that thinking of a relative being diagnosed with cancer provoked more distress, urges to neutralize, and higher estimates of likelihood, as well greater use of mental neutralizing behaviors, compared to thinking of a stranger. Contrary to our prediction, the groups did not differ in their ratings of the moral wrongness. These findings broadly support the assertion that the more personally significant a negative intrusive thought, the more it will provoke distress and urges to neutralize. Results are discussed in terms of the cognitive model of obsessions and clinical implications are addressed. PMID:21835394

  15. Buildup of the Kondo effect from real-time effective action for the Anderson impurity model

    Bock, Sebastian; Liluashvili, Alexander; Gasenzer, Thomas

    2016-07-01

    The nonequilibrium time evolution of a quantum dot is studied by means of dynamic equations for time-dependent Green's functions derived from a two-particle-irreducible (2PI) effective action for the Anderson impurity model. Coupling the dot between two leads at different voltages, the dynamics of the current through the dot is investigated. We show that the 2PI approach is capable of describing the dynamical buildup of the Kondo effect, which shows up as a sharp resonance in the spectral function, with a width exponentially suppressed in the electron self-coupling on the dot. An external voltage applied to the dot is found to deteriorate the Kondo effect at the hybridization scale. The dynamic equations are evaluated within different nonperturbative resummation schemes, within the direct, particle-particle, and particle-hole channels, as well as their combination, and the results compared with those from other methods.

  16. World-volume Effective Action of Exotic Five-brane in M-theory

    Kimura, Tetsuji; Yata, Masaya

    2016-01-01

    We study the world-volume effective action of an exotic five-brane, known as the M-theory $5^3$-brane (M$5^3$-brane) in eleven dimensions. The supermultiplet of the world-volume theory is the $\\mathcal{N} = (2, 0)$ tensor multiplet in six dimensions. The world-volume action contains three Killing vectors $\\hat{k}_{\\hat{I}} {}^M \\ (\\hat{I} =1,2,3)$ associated with the $U(1)^3$ isometry. We find the effective T-duality rule for the eleven-dimensional backgrounds that transforms the M5-brane effective action to that of the M$5^3$-brane. We also show that our action provides the source term for the M$5^3$-brane geometry in eleven-dimensional supergravity

  17. Renormalization-group flow of the effective action of cosmological large-scale structures

    Floerchinger, Stefan; Tetradis, Nikolaos; Wiedemann, Urs Achim

    2016-01-01

    Following an approach of Matarrese and Pietroni, we derive the functional renormalization group (RG) flow of the effective action of cosmological large-scale structures. Perturbative solutions of this RG flow equation are shown to be consistent with standard cosmological perturbation theory. Non-perturbative approximate solutions can be obtained by truncating the a priori infinite set of possible effective actions to a finite subspace. Using for the truncated effective action a form dictated by dissipative fluid dynamics, we derive RG flow equations for the scale dependence of the effective viscosity and sound velocity of non-interacting dark matter, and we solve them numerically. Physically, the effective viscosity and sound velocity account for the interactions of long-wavelength fluctuations with the spectrum of smaller-scale perturbations. We find that the RG flow exhibits an attractor behaviour in the IR that significantly reduces the dependence of the effective viscosity and sound velocity on the input ...

  18. On the Effective Action of Dressed Mean Fields for N = 4 Super-Yang-Mills Theory

    Gorazd Cvetic

    2006-01-01

    Full Text Available On the basis of the general considerations such as R-operation and Slavnov-Taylor identity we show that the effective action, being understood as Legendre transform of the logarithm of the path integral, possesses particular structure in N = 4 supersymmetric Yang-Mills theory for kernels of the effective action expressed in terms of the dressed effective fields. These dressed effective fields have been introduced in our previous papers as actual variables of the effective action. The concept of dressed effective fields naturally appears in the framework of solution to Slavnov-Taylor identity. The particularity of the structure is independence of these kernels on the ultraviolet regularization scale Λ. These kernels are functions of mutual spacetime distances and of the gauge coupling. The fact that β function in this theory vanishes is used significantly.

  19. Violent Juvenile Delinquents: Treatment Effectiveness and Implications for Future Action.

    Tate, David C.; And Others

    1995-01-01

    Considers the research in addressing how society should reasonably invest in the treatment of violent juvenile offenders. The authors first examine the problems of evaluating interventions with violent youth, then explore various intervention options. The use of multisystemic therapy is offered as a cost-effective program for reducing juvenile…

  20. Conformal Invariance of the D-Particle Effective Action

    Hayasaka, Kiyoshi; Nakayama, Ryuichi

    1999-01-01

    It is shown that the effective theory of D-particles has conformal symmetry with field-dependent parameters. This is a consequence of the supersymmetry. The string coupling constant is not transformed in contrast with the recent proposal of generalized conformal symmtery by Jevicki et al. This conformal symmetry can also be generalized to other Dp-brane systems.

  1. Low-energy effective action in N = 2 supersymmetric field theories

    Review of new approach to finding effective action in N = 2 and N = 4 supersymmetric theory is given. The approach is based on the formulation of these theories in terms of unconstrained superfields in harmonic superspace. Construction of superfield model of N = 2 supersymmetric field theory (hypermultiplet, N = 2 supersymmetric Yang-Mills theory) is discussed. N = 2 background field method is considered. Perturbative holomorphic effective potential in N = 2 models and non-holomorphic effective potential in N = 4 Yang-Mills field theory, defining exact low-energy effective action in this theory, are studied. Possible applications of low-energy effective action in supersymmetric theories and some open problems are discussed. Comparison of given approach with others is performed

  2. Improving Conservation Community Group Effectiveness Using Mind Mapping and Action Research

    Hanabeth Luke; David Lloyd; William Boyd; Kristin den Exter

    2014-01-01

    This paper examines a case study where mind mapping is used within an action research project to foster improved community group effectiveness and decision-making. The case study focusses on the social dynamics experienced during the formative stage of a community action group in Byron Bay, New South Wales; one of a network of such groups, formed to ensure that sustainable environmental management practices are followed in proposed coal-seam gas developments. In the context of examining syste...

  3. Short-term effects of an action video game on attention

    Onstad, Malin Bjørklund

    2015-01-01

    This study was carried out to examine whether an action video game had short-term effects on selective attention and temporal attention, as measured by the Attentional blink, Simon task and Stroop task. The design was experimental in which the participants (N = 20) completed 1 hour of action video game playing or reading in a book on two occasions, separated by 7 days. All participants completed both conditions. The design was randomized, counterbalanced and with cross-over trials. A Kolmogor...

  4. Technology and collective action: the effect of cell phone coverage on political violence in Africa

    Pierskalla, Jan H.; Hollenbach, Florian M.

    2013-01-01

    The spread of cell phone technology across Africa has transforming effects on the economic and political sphere of the continent. In this paper, we investigate the impact of cell phone technology on violent collective action. We contend that the availability of cell phones as a communication technology allows political groups to overcome collective action problems more easily and improve in-group cooperation, and coordination. Utilizing novel, spatially disaggregated data on cell phone covera...

  5. Adiponectin Action: A Combination of Endocrine and Autocrine/Paracrine Effects

    Dadson, Keith; Liu, Ying; Sweeney, Gary

    2011-01-01

    The widespread physiological actions of adiponectin have now been well characterized as clinical studies and works in animal models have established strong correlations between circulating adiponectin level and various disease-related outcomes. Thus, conventional thinking attributes many of adiponectin’s beneficial effects to endocrine actions of adipose-derived adiponectin. However, it is now clear that several tissues can themselves produce adiponectin and there is growing evidence that loc...

  6. Adiponectin action: a combination of endocrine and autocrine/paracrine effects

    Gary eSweeney

    2011-01-01

    The widespread physiological actions of adiponectin have now been well characterized as clinical studies and work in animal models have established strong correlations between circulating adiponectin levels and various disease-related outcomes. Thus, conventional thinking attributes many of adiponectins beneficial effects to endocrine actions of adipose-derived adiponectin. However, it is now clear that several tissues can themselves produce adiponectin and there is growing evidence that loca...

  7. The effects of scales, flows and filters on property rights and collective action in watershed management:

    Swallow, Brent M.; Garrity, Dennis P.; van Noordwijk, Meine

    2001-01-01

    Research and policy on property rights, collective action and watershed management requires good understanding of ecological and socio-political processes at different social-spatial scales. On-farm soil erosion is a plot or farm-level problem that can be mitigated through more secure property rights for individual farmers, while the sedimentation of streams and deterioration of water quality are larger-scale problems that may require more effective collective action and / or more secure prop...

  8. Effect of action observation therapy on daily activities and motor recovery in stroke patients

    Mei-Hong Zhu; Jing Wang; Xu-Dong Gu; Mei-Fang Shi; Ming Zeng; Chun-Yuan Wang; Qiao-Ying Chen; Jian-Ming Fu

    2015-01-01

    Objective: To evaluate the effects of action observation therapy, which is based on mirror neuron theory, on upper limb function and activities of daily living in patients with stroke. Methods: Sixty-one patients with stroke were randomly divided into two groups; those in the control group received routine rehabilitation treatment and nursing, whereas those in the experimental group additionally received eight weeks of action observation therapy for 30 min, six times per week. Patients rec...

  9. Estimation of Several Political Action Effects of Energy Prices

    Whitford, Andrew B

    2015-01-01

    One important effect of price shocks in the United States has been increased political attention paid to the structure and performance of oil and natural gas markets, along with some governmental support for energy conservation. This paper describes how price changes helped lead the emergence of a political agenda accompanied by several interventions, as revealed through Granger causality tests on change in the legislative agenda.

  10. Autocrine effects of visfatin on hepatocyte sensitivity to insulin action

    Škop, V.; Kontrová, K.; Zídek, Václav; Pravenec, Michal; Kazdová, L.; Mikulík, Karel; Sajdok, J.; Zídková, J.

    2010-01-01

    Roč. 59, č. 4 (2010), s. 615-618. ISSN 0862-8408 R&D Projects: GA AV ČR(CZ) IAA500110805; GA MŠk(CZ) ME08006; GA MZd(CZ) NR9387; GA MZd(CZ) NR9359 Institutional research plan: CEZ:AV0Z50110509; CEZ:AV0Z50200510 Keywords : Visfatin * RNA interference * insulin mimetic effects Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.646, year: 2010

  11. Causality-based cost-effective action mining

    Shamsinejadbabaki, Pirooz; Saraee, Mohamad; Blockeel, Hendrik

    2013-01-01

    In many business contexts, the ultimate goal of knowledge discovery is not the knowledge itself, but putting it to use. Models or patterns found by data mining methods often require further post-processing to this effect. For instance, in churn prediction, data mining may give a model that predicts which customers are likely to end their contract, but companies are not just interested in knowing who is likely to do so, they want to know what they can do to avoid this. The models or patterns h...

  12. The differentiated effects of CSR actions in the service industry

    Casado-Díaz, Ana B.; Nicolau, Juan Luis; Ruiz Moreno, Manuel Felipe; Sellers Rubio, Ricardo

    2014-01-01

    Purpose – The purpose of this study is to attempt to explain why the impact of Corporate Social Responsibility (CSR) initiatives may be different and/or more important in service firms compared to manufacturing firms. CSR is becoming a common strategy, hence its extensive research. Central to it is the analysis of the effect of CSR on a firm’s performance, whose outcome depends on firm-specific and industry-related factors. Design/methodology/approach – The event study methodology is applied ...

  13. Effective Swimmer’s Action during the Grab Start Technique

    Mourão, Luis; de Jesus, Karla; Roesler, Hélio; Machado, Leandro J.; Fernandes, Ricardo J.; Vilas-Boas, João Paulo; Vaz, Mário A. P.

    2015-01-01

    The external forces applied in swimming starts have been often studied, but using direct analysis and simple interpretation data processes. This study aimed to develop a tool for vertical and horizontal force assessment based on the swimmers’ propulsive and structural forces (passive forces due to dead weight) applied during the block phase. Four methodological pathways were followed: the experimented fall of a rigid body, the swimmers’ inertia effect, the development of a mathematical model to describe the outcome of the rigid body fall and its generalization to include the effects of the inertia, and the experimental swimmers’ starting protocol analysed with the inclusion of the developed mathematical tool. The first three methodological steps resulted in the description and computation of the passive force components. At the fourth step, six well-trained swimmers performed three 15 m maximal grab start trials and three-dimensional (3D) kinetic data were obtained using a six degrees of freedom force plate. The passive force contribution to the start performance obtained from the model was subtracted from the experimental force due to the swimmers resulting in the swimmers’ active forces. As expected, the swimmers’ vertical and horizontal active forces accounted for the maximum variability contribution of the experimental forces. It was found that the active force profile for the vertical and horizontal components resembled one another. These findings should be considered in clarifying the active swimmers’ force variability and the respective geometrical profile as indicators to redefine steering strategies. PMID:25978370

  14. Evolution of the violin: The law of effect in action.

    Wasserman, Edward A; Cullen, Patrick

    2016-01-01

    As is true for most other human inventions, the origin of the violin is unknown. What is known is that this popular and versatile instrument has notably changed over the course of several hundred years. At issue is whether those evolutionary changes in the construction of the violin are the result of premeditated, intelligent design or whether they arose through a trial-and-error process. Recent scientific evidence favors the latter account. Our perspective piece puts these recent empirical findings into a comprehensive selectionist framework. According to this view, the many things we do and make--like violins--arise from a process of variation and selection which accords with the law of effect. Contrary to popular opinion, there is neither mystique nor romance in this process; it is as fundamental and ubiquitous as the law of natural selection. As with the law of natural selection in the evolution of organisms, there is staunch resistance to the role of the law of effect in the evolution of human inventions. We conclude our piece by considering several objections to our perspective. PMID:26569015

  15. Dynamical Tides in General Relativity: Effective Action and Effective-One-Body Hamiltonian

    Steinhoff, Jan; Buonanno, Alessandra; Taracchini, Andrea

    2016-01-01

    Tidal effects have an important impact on the late inspiral of compact binary systems containing neutron stars. Most current models of tidal deformations of neutron stars assume that the tidal bulge is directly related to the tidal field generated by the companion, with a constant response coefficient. However, if the orbital motion approaches a resonance with one of the internal modes of the neutron star, this adiabatic description of tidal effects starts to break down, and the tides become dynamical. In this paper, we consider dynamical tides in general relativity due to the quadrupolar fundamental oscillation mode of a neutron star. We devise a description of the effects of the neutron star's finite size on the orbital dynamics based on an effective point-particle action augmented by dynamical quadrupolar degrees of freedom. We analyze the post-Newtonian and test-particle approximations of this model and incorporate the results into an effective-one-body Hamiltonian. This enables us to extend the descripti...

  16. 10D to 4D Euclidean Supergravity over a Calabi-Yau three-fold

    Sabra, Wafic

    2015-01-01

    We dimensionally reduce the bosonic sector of 10D Euclidean type IIA supergravity over a Calabi-Yau three-fold. The resulting theory describes the bosonic sector of 4D, N = 2 Euclidean supergravity coupled to vector- and hyper-multiplets.

  17. Covariant and single-field effective action with the background-field formalism

    Safari, Mahmoud

    2016-01-01

    In the context of scalar quantum field theory we introduce a class of generically nonlinear quantum-background splits for which the splitting Ward identity, encoding the single field dependence in the effective action, can be solved exactly. We show that this can be used to construct an effective action which is both covariant and dependent on the background and fluctuation fields only through a single total field in a way independent from the dynamics. Moreover we discuss the criteria under which the ultraviolet symmetries are inherited by the quantum effective action. The approach is demonstrated through some examples, including the $O(N)$ effective field theory, which might be of interest for the Higgs sector of the Standard Model or its extensions.

  18. Differential effects of thioridazine enantiomers on action potential duration in rabbit papillary muscle

    Jensen, Ask Schou; Pennisi, Cristian Pablo; Sevcencu, Cristian;

    2015-01-01

    (+)-thioridazine. In this study we for the first time investigate the cardiotoxicity of the isolated thioridazine enantiomers and show their effects on ventricular repolarization. The effects of (+)-thioridazine, (-)-thioridazine, and racemate on the rabbit ventricular action potential duration (APD) were...... investigated in a randomized controlled blinded experiment. Action potentials were measured in papillary muscles isolated from 21 female rabbits, and the drug effect on 90% APD in comparison with control (DeltaDelta-APD90) was evaluated. Increasing concentrations of (+)-thioridazine and the racemate caused...

  19. The low-energy N=4 SYM effective action in diverse harmonic superspaces

    Buchbinder, I L; Samsonov, I B

    2016-01-01

    We review various superspace approaches to the description of the low-energy effective action in N=4 super Yang-Mills (SYM) theory. We consider the four-derivative part of the low-energy effective action in the Coulomb branch. The typical components of this effective action are the gauge field F^4/X^4 and the scalar field Wess-Zumino terms. We construct N=4 supersymmetric completions of these terms in the framework of different harmonic superspaces supporting N=2,3,4 supersymmetries. These approaches are complementary to each other in the sense that they make manifest different subgroups of the total SU(4) R-symmetry group. We show that the effective action acquires an extremely simple form in those superspaces which manifest the non-anomalous maximal subgroups of SU(4). The common characteristic feature of our construction is that we restore the superfield effective actions exclusively by employing the N=4 supersymmetry and/or superconformal PSU(2,2|4) symmetry.

  20. Reviewing Biosphere Reserves globally: effective conservation action or bureaucratic label?

    Coetzer, Kaera L; Witkowski, Edward T F; Erasmus, Barend F N

    2014-02-01

    The Biosphere Reserve (BR) model of UNESCO's Man and the Biosphere Programme reflects a shift towards more accountable conservation. Biosphere Reserves attempt to reconcile environmental protection with sustainable development; they explicitly acknowledge humans, and human interests in the conservation landscape while still maintaining the ecological values of existing protected areas. Conceptually, this model is attractive, with 610 sites currently designated globally. Yet the practical reality of implementing dual 'conservation' and 'development' goals is challenging, with few examples successfully conforming to the model's full criteria. Here, we review the history of Biosphere Reserves from first inception in 1974 to the current status quo, and examine the suitability of the designation as an effective conservation model. We track the spatial expansion of Biosphere Reserves globally, assessing the influence of the Statutory Framework of the World Network of Biosphere Reserves and Seville strategy in 1995, when the BR concept refocused its core objectives on sustainable development. We use a comprehensive range of case studies to discuss conformity to the Programme, the social and ecological consequences associated with implementation of the designation, and challenges in aligning conservation and development. Given that the 'Biosphere Reserve' label is a relatively unknown designation in the public arena, this review also provides details on popularising the Biosphere Reserve brand, as well as prospects for further research, currently unexploited, but implicit in the designation. PMID:23701641

  1. Effect of Action Video Games on the Spatial Distribution of Visuospatial Attention

    Green, C. Shawn; Bavelier, Daphne

    2006-01-01

    The authors investigated the effect of action gaming on the spatial distribution of attention. The authors used the flanker compatibility effect to separately assess center and peripheral attentional resources in gamers versus nongamers. Gamers exhibited an enhancement in attentional resources compared with nongamers, not only in the periphery but…

  2. Extracting the effective Polyakov line action from SU(2) and SU(3) lattice gauge theories

    Greensite, Jeff

    2013-01-01

    We describe the "relative weights" method used to compute the effective Polyakov line action corresponding to a given lattice gauge theory, and present some results that have been obtained so far. The main motivation is the sign problem, which may be easier to address in the effective theory than in the underlying gauge theory.

  3. Voluntary action and tactile sensory feedback in the intentional binding effect.

    Zhao, Ke; Hu, Li; Qu, Fangbing; Cui, Qian; Piao, Qiuhong; Xu, Hui; Li, Yanyan; Wang, Liang; Fu, Xiaolan

    2016-08-01

    The intentional binding effect refers to a subjective compression over a temporal interval between the start point initialized by a voluntary action and the endpoint signaled by an external sensory (visual or audio) feedback. The present study aimed to explore the influence of tactile sensory feedback on this binding effect by comparing voluntary key-press actions with voluntary key-release actions. In experiment 1, each participant was instructed to report the perceived interval (in ms) between an action and the subsequent visual sensory feedback. In this task, either the action (key-press or key-release) was voluntarily performed by the participant or a kinematically identical movement was passively applied to the left index finger of the participant. In experiment 2, we explored whether the difference in the perception of time was affected by the direction of action. In experiment 3, we developed an apparatus in which two parallel laser beams were generated by a laser emission unit and detected by a laser receiver unit; this allowed the movement of the left index finger to be detected without it touching a keyboard (i.e., without any tactile sensory feedback). Convergent results from all of the experiments showed that the temporal binding effect was only observed when the action was both voluntary and involved physical contact with the key, suggesting that the combination of intention and tactile sensory feedback, as a form of top-down processing, likely distracted attention from temporal events and caused the different binding effects. PMID:27038203

  4. Renal Vasodilatory Action of Dopamine in Patients With Heart Failure: Magnitude of Effect and Site of Action.

    Elkayam, Uri; Ng, Tien M H; Hatamizadeh, Parta; Janmohamed, Munir; Mehra, Anilkumar

    2008-01-15

    BACKGROUND: A "renal dose" of dopamine is often used to increase renal blood flow; however, data on the magnitude of effect and site of action in patients with heart failure are scarce. METHODS AND RESULTS: Renal effects of intravenous dopamine (1, 2, 3, 5, and 10 mug . kg(-1) . min(-1)) were evaluated in 13 patients with chronic heart failure. Renal blood flow was calculated from renal artery cross-sectional area measured with intravascular ultrasound and renal blood flow velocity-time integral measured by the intravascular Doppler technique. Cross-sectional area increased and was significantly higher than baseline (0.30+/-0.04 cm(2)) at 5 mug . kg(-1) . min(-1) (0.36+/-0.05 cm(2)) and 10 mug . kg(-1) . min(-1) (0.38+/-0.06 cm(2)). The velocity-time integral was significantly higher than baseline (22+/-3 cm) at doses of 3 and 5 mug . kg(-1) . min(-1) (both 31+/-4 cm). Renal blood flow increased, whereas renal vascular resistance decreased, reaching statistical significance at 2 mug . kg(-1) . min(-1) through 10 mug . kg(-1) . min(-1). Cardiac output gradually increased, reaching statistical significance at doses of 5 and 10 mug . kg(-1) . min(-1) (5.5+/-0.5 and 6.1+/-0.7 versus 4.5+/-5.2 L/min at baseline), but the increase in renal blood flow appeared proportionately larger than corresponding increases in cardiac output. CONCLUSIONS: Dopamine is associated with an increase in renal blood flow in patients with heart failure. This effect is due to dilation of both the large conductance and small resistance renal blood vessels. Further evaluation of the efficacy and safety of dopamine for improvement of renal function in hospitalized patients with heart failure is warranted. PMID:18172028

  5. The combined effect of precession and convection on the dynamo action

    Wei, Xing

    2016-01-01

    To understand the generation of the Earth's and planetary magnetic fields, we investigate numerically the combined effect of precession and convection on the dynamo action in a spherical shell. The convection alone, the precession alone and the combined effect of convection and precession are studied at the low Ekman number at which the precessing flow is already unstable. The key result is that although the precession or convection alone is not strong to support the dynamo action the combined effect of precession and convection can support the dynamo action because of the resonance of precessional and convective instabilities. This result may interpret why the geodynamo maintains for such a long history compared to the Martian dynamo.

  6. The effective action for edge states in higher-dimensional quantum Hall systems

    We show that the effective action for the edge excitations of a quantum Hall droplet of fermions in higher dimensions is generically given by a chiral bosonic action. We explicitly analyze the quantum Hall effect on complex projective spaces CPk, with a U(1) background magnetic field. The edge excitations are described by Abelian bosonic fields on S2k-1 with only one spatial direction along the boundary of the droplet relevant for the dynamics. Our analysis also leads to an action for edge excitations for the case of the Zhang-Hu four-dimensional quantum Hall effect defined on S4 with an SU(2) background magnetic field, using the fact that CP3 is an S2-bundle over S4

  7. Two-loop low-energy effective action in Abelian supersymmetric Chern–Simons matter models

    We compute two-loop low-energy effective actions in Abelian Chern–Simons matter models with N=2 and N=3 supersymmetry up to four-derivative order. Calculations are performed with a slowly-varying gauge superfield background. Though the gauge superfield propagator depends on the gauge fixing parameter, it is shown that the obtained results are independent of this parameter. In the massless case the considered models are superconformal. We demonstrate that the superconformal symmetry strongly restricts the form of two-loop quantum corrections to the effective actions such that the obtained terms have simpler structure than the analogous ones in the effective action of three-dimensional supersymmetric electrodynamics (SQED) with vanishing topological mass

  8. Effective actions in ${\\cal N}$=1, D5 supersymmetric gauge theories: harmonic superspace approach

    Buchbinder, I L

    2015-01-01

    We consider the off-shell formulation of the 5D, $ {\\cal N}$=1 super Yang-Mills and super Chern-Simons theories in harmonic superspace. Using such a formulation we develop a manifestly supersymmetric and gauge invariant approach to constructing the one-loop effective action both in super Yang-Mills and super Chern-Simons models. On the base of this approach we compute the leading low-energy quantum contribution to the effective action on the Abelian vector multiplet background. This contribution corresponds to $F^4$ invariant which is given in 5D superfield form.

  9. Evaluative priming reveals dissociable effects of cognitive versus physiological anxiety on action monitoring.

    De Saedeleer, Lien; Pourtois, Gilles

    2016-06-01

    Performance monitoring enables the rapid detection of mismatches between goals or intentions and actions, as well as subsequent behavioral adjustment by means of enhanced attention control. These processes are not encapsulated, but they are readily influenced by affective or motivational variables, including negative affect. Here we tested the prediction that worry, the cognitive component of anxiety, and arousal, its physiological counterpart, can each influence specific processes during performance monitoring. In 2 experiments, participants were asked to discriminate the valence of emotional words that were preceded by either correct (good) or incorrect (bad) actions, serving as primes in a standard evaluative priming procedure. In Experiment 1 (n = 36) we examined the influence of trait worry and arousal. Additionally, we included a face priming task to examine the specificity of this effect. Stepwise linear regression analyses showed that increased worry, but not arousal, weakened the evaluative priming effect and therefore the rapid and automatic processing of actions as good or bad. By contrast, arousal, but not worry, increased posterror slowing. In Experiment 2 (n = 30) state worry was induced using an anagram task. Effects of worry on action monitoring were trait but not state dependent, and only evidenced when actions were directly used as primes. These results suggest a double dissociation between worry and arousal during performance monitoring. (PsycINFO Database Record PMID:26709858

  10. Covariant and background independent functional RG flow for the effective average action

    Safari, Mahmoud

    2016-01-01

    We extend our prescription for the construction of a covariant and background-independent effective action for scalar quantum field theories to the case where momentum modes below a certain scale are suppressed by the presence of an infrared regulator. The key step is an appropriate choice of the infrared cutoff for which the Ward identity, capturing the information from single-field dependence of the ultraviolet action, continues to be exactly solvable, and therefore, in addition to covariance, manifest background independence of the effective action is guaranteed at any scale. A practical consequence is that in this framework one can adopt truncations dependent on the single total field. Furthermore we discuss the necessary and sufficient conditions for the preservation of symmetries along the renormalization group flow.

  11. Community ACTION Boards: An Innovative Model for Effective Community–Academic Research Partnerships

    James, Sherline; Arniella, Guedy; Bickell, Nina A.; Walker, Willie; Robinson, Virginia; Taylor, Barbara; Horowitz, Carol R.

    2012-01-01

    Background Community-based participatory research (CBPR) requires equitable partnerships between community stakeholders and academics. Traditionally, researchers relied on community advisory boards, but these boards often play a reactive role on a project-by-project basis. The East and Central Harlem Health Outcomes (ECHHO) Community Action Board (CAB), however, is an effective, proactive group. Objectives The ECHHO board sought to identify key strategies and tools to build and employ a partnership model, and to disseminate lessons learned to other community–academic partnerships. Methods Current and former board members were interviewed and a wide range of related documents was reviewed. Lessons Learned The board became effective when it prioritized action and relationship-building, across seven key domains: Shared priorities, diversity, participation, transparency, mutual respect and recognition, and personal connections. The model is depicted graphically. Conclusion Community advisory boards may benefit from attention to taking action, and to building relationships between academics and community members. PMID:22616207

  12. Effect of Fuzheng Huayu formula and its actions against liver fibrosis

    Xu Lieming

    2009-06-01

    Full Text Available Abstract Liver fibrosis is a common histological process to develop into cirrhosis in various chronic liver diseases including chronic hepatitis and fatty liver. Therefore anti-liver fibrosis is very important strategy to treat chronic liver diseases. Fuzheng Huayu (FZHY, a preparation containing herbs such as Radix Salvia Miltiorrhizae, Cordyceps, Semen Persicae, was formulated on the basis of Chinese medicine theory in treating liver fibrosis and was approved. Pharmacological studies and clinical trials demonstrate that FZHY has a significant effect against liver fibrosis and that many of the pharmacological actions are attributable to the effect. This article reviews the effects and actions of FZHY, in particular the effects observed from clinical trials in treating liver fibrosis caused by chronic hepatitis B and the actions on inhibition of hepatic stellate cell activation, protection of hepatocytes and inhibition of hepatic sinusoidal capillarization. This article also reviews the coordinated effects of the constituent herbs of FZHY and the actions of their active compounds such as salvianonic acid B (SA-B on liver fibrosis.

  13. Effects of certain muscarinic antagonists on the actions of anticholinesterases on cat skeletal muscle.

    Brimblecombe, R W; French, M C; Webb, S N

    1979-04-01

    1. The effects of some muscarinic antagonists, namely, N-ethyl-2-pyrrolidylmethyl-cyclopentylphenyl glycollate (PMCG), N-methyl-4-piperidyl-phenylcyclohexyl glycollate (PPCG, racemate and R and S enantiomers) and 4'-N-methyl-piperidyl-1-phenyl-cyclopentane carboxylate (G3063) on organophosphate (sarin, soman)- and carbamate (neostigmine)-induced twitch augmentation have been studied in cat soleus muscle. 2. The results of a preliminary study comparing the potency of sarin and soman in inhibiting the acetylcholinesterase activity of muscle in relation to the effect on the maximal twitch response indicated that there is not a simple relationship between degree of enzyme inhibition by these drugs and alteration of muscle function. 3. The muscarinic antagonists studied were capable of preventing or reversing sarin-, soman- or neostigmine-induced twitch augmentation. Doses sufficient to give complete protection from the effects of the anticholinesterase agents had little or no effect on the twitch response of normal muscle. 4. The protective action of these muscarinic antagonists is dose-dependent but independent of known antagonist actions at muscarinic receptors. 5. The effects of some local anaesthetics (lignocaine, prilocaine, cinchocaine, procaine) and other membrane stabilizers (quinine, ketamine, chlorpromazine, triflupromazine) were compared with those of the muscarinic antagonists in an attempt to elucidate the mode of action of these acetylcholine antagonists. The evidence is insufficient to exclude the involvement of a membrane stabilizing action. PMID:435681

  14. The combined effects of action observation and passive proprioceptive training on adaptive motor learning.

    Lei, Yuming; Bao, Shancheng; Wang, Jinsung

    2016-09-01

    Sensorimotor adaptation can be induced by action observation, and also by passive training. Here, we investigated the effect of a protocol that combined action observation and passive training on visuomotor adaptation, by comparing it with the effect of action observation or passive training alone. Subjects were divided into five conditions during the training session: (1) action observation, in which the subjects watched a video of a model who adapted to a novel visuomotor rotation; (2) proprioceptive training, in which the subject's arm was moved passively to target locations that were associated with desired trajectories; (3) combined training, in which the subjects watched the video of a model during a half of the session and experienced passive movements during the other half; (4) active training, in which the subjects adapted actively to the rotation; and (5) a control condition, in which the subjects did not perform any task. Following that session, all subjects adapted to the same visuomotor rotation. Results showed that the subjects in the combined training condition adapted to the rotation significantly better than those in the observation or proprioceptive training condition, although their performance was not as good as that of those who adapted actively. These findings suggest that although a protocol that combines action observation and passive training consists of all the processes involved in active training (error detection and correction, effector-specific and proprioceptively based reaching movements), these processes in that protocol may work differently as compared to a protocol in which the same processes are engaged actively. PMID:27298007

  15. Short Term Effectiveness of High Density Large Woody Debris in Asotin Creek as a Cheap and Cheerful Restoration Restoration Action

    Camp, Reid

    2015-01-01

    In response to human impacts, river restoration and rehabilitation actions have become a priority in the United States. In the Pacific Northwest, most restoration actions are focused on repairing degraded freshwater habitat to increase or improve Pacific salmonid production. However, traditional river restoration actions remained largely unchanged for over 100 years despite a lack of definitive evidence that the actions were effective. More recently, there has been a surge in process-based re...

  16. Modulatory effect of raloxifene and estrogen on the metabolic action of growth hormone in hypopituitary women.

    Birzniece, Vita

    2010-05-01

    The metabolic action of GH is attenuated by estrogens administered via the oral route. Selective estrogen receptor modulators lower IGF-I to a lesser degree than 17beta-estradiol in GH-deficient women, and their effect on fat and protein metabolism is unknown.

  17. Positive Education for School Leaders: Exploring the Effects of Emotion-Gratitude and Action-Gratitude

    Waters, Lea; Stokes, Helen

    2015-01-01

    This qualitative study describes the effect of two gratitude interventions designed to trigger emotion-gratitude (gratitude diary) and action-gratitude (gratitude letter) in school leaders. Case study methodology was applied to analyse reflective journals of 27 school leaders. The gratitude diary served to foster a more balanced view of the…

  18. Non-abelian chiral anomalies and Wess-Zumino effective actions

    An elementary account is given of the construction of anomalies and effective actions for Goldstone bosons, using the techniques of differential geometry. The emphasis is on simplicity of presentation, comparison of different renormalization schemes and the relationship to bosonization in the case of 2 dimensions. (Auth.)

  19. Action Control and Dispositional Hope: An Examination of Their Effect on Self-Regulated Learning

    Papantoniou, Georgia; Moraitou, Despina; Katsadima, Effie; Dinou, Magda

    2010-01-01

    Introduction: The present study examined the effect of action control (i.e., disengagement, initiative, and persistence) and dispositional hope (i.e., pathways thought, and agency thinking) on self-regulated learning strategy use (i.e., cognitive, metacognitive, and resource management) and course achievement. Method: A total of 275 undergraduate…

  20. Effective action for order parameters and the problem of phase transitions in lattice QCD thermodynamics

    The phase structure of lattice SU(N)-chromodynamics is discussed. An effective action for Polyakov lines of quark and baryon condensates is constructed for the Euclidean formulation of theory with naive fermions at finite temperatures and baryon number densities. The behaviour of respective averages and the interrelation between them are studied. 25 refs

  1. Wogonin potentiates the antitumor action of etoposide and ameliorates its adverse effects.

    Enomoto, Riyo; Koshiba, Chika; Suzuki, Chie; Lee, Eibai

    2011-05-01

    Wogonin, a flavone in the roots of Scutellaria baicalensis, reduced etoposide-induced apoptotic cell death in normal cells, such as bone marrow cells and thymocytes. On the other hand, wogonin potentiated the proapoptotic or cytotoxic action of etoposide in tumor cells, such as Jurkat, HL-60, A549, and NCI-H226. These contradictory actions of wogonin on apoptosis are distinguished by normal or cancer cell types. Wogonin had no effect on apoptosis induced by other anticancer agents in the tumor cells. Thus, the potentiation effect of wogonin was observed only in etoposide-induced apoptosis in tumor cells. In a functional assay for P-glycoprotein (P-gp), wogonin suppressed excretion of calcein, a substrate for P-gp, in these tumor cells. Moreover, wogonin decreased the excretion of radiolabeled etoposide and accordingly increased intracellular content of this agent in the cells. P-gp inhibitors showed a similar potentiation effect on etoposide-induced apoptosis in these tumor cells. Thus, wogonin is likely to potentiate the anticancer action of etoposide due to P-gp inhibition and accumulation of this agent. These findings suggest that wogonin may be a useful chemotherapeutic adjuvant to potentiate the pharmacological action of etoposide and ameliorate its adverse effects. PMID:20658136

  2. Characterizing Teaching Effectiveness in the Joint Action Theory in Didactics: An Exploratory Study in Primary School

    Sensevy, Gérard

    2014-01-01

    This paper presents an exploratory study of two consecutive reading sessions conducted in primary school by two different teachers. Our purpose is twofold. From a theoretical viewpoint, we propose a tentative set of conditions of teaching effectiveness by relying on the Joint Action Theory in Didactics. From a methodological viewpoint, drawing on…

  3. The N=4 effective action of type IIA supergravity compactified on SU(2)-structure manifolds

    Danckaert, Thomas; Martínez-Pedrera, Danny; Spanjaard, Bastiaan; Triendl, Hagen

    2011-01-01

    We study compactifications of type IIA supergravity on six-dimensional manifolds with SU(2) structure and compute the low-energy effective action in terms of the non-trivial intrinsic torsion. The consistency with gauged N=4 supergravity is established and the gauge group is determined. Depending on the structure of the intrinsic torsion, antisymmetric tensor fields can become massive.

  4. Induced low-energy effective action in the 6D, N = (1 , 0) hypermultiplet theory on the vector multiplet background

    Buchbinder, I. L.; Merzlikin, B. S.; Pletnev, N. G.

    2016-08-01

    We consider the six dimensional N = (1 , 0) hypermultiplet model coupled to an external field of the Abelian vector multiplet in harmonic superspace approach. Using the superfield proper-time technique we find the divergent part of the effective action and derive the complete finite induced low-energy superfield effective action. This effective action depends on external field and contains in bosonic sector all the powers of the constant Maxwell field strength. The obtained result can be treated as the 6D, N = (1 , 0) supersymmetric Heisenberg-Euler type effective action.

  5. The Effect of Sympathetic Antagonists on the Antidepressant Action of Alprazolam

    Gorash ZM

    2008-01-01

    Full Text Available Alprazolam is an anti-anxiety drug shown to be effective in the treatment of depression. In this study, the effect of sympathetic receptor antagonists on alprazolam–induced antidepressant action was studied using a mouse model of forced swimming behavioral despair. The interaction of three sympathetic receptor antagonists with benzodiazepines, which may impact the clinical use of alprazolam, was also studied. Behavioral despair was examined in six groups of albino mice. Drugs were administered intraperitoneally. The control group received only a single dose of 1% Tween 80. The second group received a single dose of alprazolam, and the third group received an antagonist followed by alprazolam. The fourth group was treated with imipramine, and the fifth group received an antagonist followed by imipramine. The sixth group was treated with a single dose of an antagonist alone (atenolol, a β1-selective adrenoceptor antagonist; propranolol, a non selective β-adrenoceptor antagonist; and prazocin, an α1-adrenoceptor antagonist. Results confirmed the antidepressant action of alprazolam and imipramine. Prazocin treatment alone produced depression, but it significantly potentiated the antidepressant actions of imipramine and alprazolam. Atenolol alone produced an antidepressant effect and potentiated the antidepressant action of alprazolam. Propranolol treatment alone produced depression, and antagonized the effects of alprazolam and imipramine, even producing depression in combined treatments. In conclusion, our results reveal that alprazolam may produce antidepressant effects through the release of noradrenaline, which stimulates β2 receptors to produce an antidepressant action. Imipramine may act by activating β2 receptors by blocking or down-regulating β1 receptors.

  6. Effects of benactyzine on action potentials and contractile force of guinea pig papillary muscles

    2000-01-01

    Aim:To explore the effects of benactyzine (BEN) on the action potential and contractile force in guinea pig papillary muscles.Methods:Conventional microelectrode technique was used to record the fast action potentials (FAP) and slow action potentials (SAP) of guinea pig papillary muscles.Results:Benactyzine 5,10,50 μmol·L-1 suppressed the maximal upstroke velocity (vmax) of FAP and contractile force (Fc) concentration-dependently while prolonged the action potential duration at 50%,90% repolarization (APD50,APD90) and effective refractory period (ERP) of FAP.The suppression on the vmax was frequency-dependent.Benactyzine 5,10,50μmol·L-1 lengthened the APD50,APD90 of SAP induced by isoprenaline or histamine when perfused with KCl 22 mmol·L-1 Tyrode's solution.The vmax of the SAP was not decreased by benactyzine 5,10 μmol·L-1 but by 50 μmol·L-1.The effects on the SAP were antagonized by elevation of the extracellular calcium from 2.0 to 5.6 mmol·L-1.The effects of benactyzine on SAP elicited by tetrodotoxin resembled that by isoprenaline or histamine except the more pronounced suppression on vmax and action potential amplitude (APA).The persistent rapid spontaneous activity and triggered tachyarrhythmia induced by ouabain were also abolished immediately by benactyzine 5 μmol·L-1.Conclusion:Benactyzine can inhibit Na+,K+,Ca2+ transmembrane movement and intracellular Ca2+ mobilization in the myocardium,and this may be the electrophysiological basis of its effects against experimental arrhythmias.

  7. THE EFFECTS OF MAINTENANCE ACTIONS ON THE PFDavg OF SPRING OPERATED PRESSURE RELIEF VALVES

    Harris, S.; Gross, R.

    2014-04-01

    The safety integrity level (SIL) of equipment used in safety instrumented functions is determined by the average probability of failure on demand (PFDavg) computed at the time of periodic inspection and maintenance, i.e., the time of proof testing. The computation of PFDavg is generally based solely on predictions or estimates of the assumed constant failure rate of the equipment. However, PFDavg is also affected by maintenance actions (or lack thereof) taken by the end user. This paper shows how maintenance actions can affect the PFDavg of spring operated pressure relief valves (SOPRV) and how these maintenance actions may be accounted for in the computation of the PFDavg metric. The method provides a means for quantifying the effects of changes in maintenance practices and shows how these changes impact plant safety.

  8. Feature activation during word recognition: action, visual, and associative-semantic priming effects

    Kevin J.Y. Lam

    2015-05-01

    Full Text Available Embodied theories of language postulate that language meaning is stored in modality-specific brain areas generally involved in perception and action in the real world. However, the temporal dynamics of the interaction between modality-specific information and lexical-semantic processing remain unclear. We investigated the relative timing at which two types of modality-specific information (action-based and visual-form information contribute to lexical-semantic comprehension. To this end, we applied a behavioral priming paradigm in which prime and target words were related with respect to (1 action features, (2 visual features, or (3 semantically associative information. Using a Go/No-Go lexical decision task, priming effects were measured across four different inter-stimulus intervals (ISI = 100 ms, 250 ms, 400 ms, and 1,000 ms to determine the relative time course of the different features . Notably, action priming effects were found in ISIs of 100 ms, 250 ms, and 1,000 ms whereas a visual priming effect was seen only in the ISI of 1,000 ms. Importantly, our data suggest that features follow different time courses of activation during word recognition. In this regard, feature activation is dynamic, measurable in specific time windows but not in others. Thus the current study (1 demonstrates how multiple ISIs can be used within an experiment to help chart the time course of feature activation and (2 provides new evidence for embodied theories of language.

  9. Inverse Scattering Method and Soliton Solution Family for String Effective Action

    GAO Ya-Jun

    2009-01-01

    A modified Hauser-Ernst-type linear system is established and used to develop an inverse scattering method for solving the motion equations of the string effective action describing the coupled gravity, dilaton and Kalb-Ramond fields. The reduction procedures in this inverse scattering method are found to be fairly simple, which makes the proposed inverse scattering method applied fine and effective. As an application, a concrete family of soliton solutions for the considered theory is obtained.

  10. Mechanisms of action underlying the antiandrogenic effects of the fungicide prochloraz

    Laier, Peter; Metzdorff, Stine Broeng; Boberg, Julie; Hagen, Marie; Hass, Ulla; Christiansen, Sofie; Petersen, Marta Axelstad; Kledal, Thuri; Dalgaard, Majken; McKinnell, C.; Brokken, L. J. S.; Vinggaard, Anne

    2006-01-01

    The fungicide prochloraz has got multiple mechanisms of action that may influence the demasculinizing and reproductive toxic effects of the compound. In the present study, Wistar rats were dosed perinatally with prochloraz (50 and 150 mg/kg/day) from gestational day (GD) 7 to postnatal day (PND) ...... prochloraz acts directly on the fetal testis to inhibit steroidogenesis and that this effect is exhibited at protein, and not at genomic, level. (c) 2005 Elsevier Inc. All rights reserved....

  11. Effect of Action Video Games on the Spatial Distribution of Visuospatial Attention

    Green, C. Shawn; Bavelier, Daphne

    2006-01-01

    The authors investigated the effect of action gaming on the spatial distribution of attention. The authors used the flanker compatibility effect to separately assess center and peripheral attentional resources in gamers versus nongamers. Gamers exhibited an enhancement in attentional resources compared with nongamers, not only in the periphery but also in central vision. The authors then used a target localization task to unambiguously establish that gaming enhances the spatial distribution o...

  12. Reducing aggressive intergroup action tendencies : effects of intergroup contact via perceived intergroup threat

    Schmid, K.; Hewstone, M.; Küpper, B.; Zick, A.; Tausch, N.

    2014-01-01

    Katharina Schmid and Miles Hewstone gratefully acknowledge support from the Leverhulme Trust that facilitated the writing of this paper. Two studies tested the prediction that more positive intergroup contact would be associated with reduced aggressive intergroup action tendencies, an effect predicted to occur indirectly via reduced intergroup threat perceptions, and over and above well-established effects of contact on intergroup attitudes. Study 1, using data based on a cross-section of ...

  13. Mechanism of Action of the Arylomycin Antibiotics and Effects of Signal Peptidase I Inhibition

    Smith, Peter A.; Romesberg, Floyd E.

    2012-01-01

    Clinically approved antibiotics inhibit only a small number of conserved pathways that are essential for bacterial viability, and the physiological effects of inhibiting these pathways have been studied in great detail. Likewise, characterizing the effects of candidate antibiotics that function via novel mechanisms of action is critical for their development, which is of increasing importance due to the ever-growing problem of resistance. The arylomycins are a novel class of natural-product a...

  14. Wess-Zumino-Witten action and photons from the Chiral Magnetic Effect

    Fukushima, Kenji; Mameda, Kazuya

    2012-01-01

    We revisit the Chiral Magnetic Effect (CME) using the chiral Lagrangian. We demonstrate that the electric-current formula of the CME is derived immediately from the contact part of the Wess-Zumino-Witten action. This implies that the CME could be, if observed, a signature for the local parity violation, but a direct evidence for neither quark deconfinement nor chiral restoration. We also discuss the reverse Chiral Magnetic Primakoff Effect, i.e. the real photon production through the vertex a...

  15. Promoting the translation of intentions into action by implementation intentions: Behavioral effects and physiological correlates

    Frank eWieber

    2015-07-01

    Full Text Available The present review addresses the physiological correlates of planning effects on behavior. Although intentions to act qualify as predictors of behavior, accumulated evidence indicates that there is a substantial gap between even strong intentions and subsequent action. One effective strategy to reduce this intention-behavior gap is the formation of implementation intentions that specify when, where, and how to act on a given goal in an if-then format (If I encounter situation Y, then I will initiate action Z!. It has been proposed that implementation intentions render the mental representation of the situation highly accessible and establish a strong associative link between the mental representations of the situation and the action. These process assumptions have been examined in behavioral research, and in physiological research, a field that has begun to investigate the temporal dynamics of and brain areas involved in implementation intention effects. In the present review, we first summarize studies on the cognitive processes that are central to the strategic automation of action control by implementation intentions. We then examine studies involving critical samples with impaired self-regulation. Lastly, we review studies that have applied physiological measures such as heart rate, cortisol level, and eye movement, as well as electroencephalography (EEG and functional magnetic resonance imaging (fMRI studies on the neural correlates of implementation intention effects. In support of the assumed processes, implementation intentions increased goal attainment in studies on cognitive processes and in critical samples, modulated brain waves related to perceptual and decision processes, and generated less activity in brain areas associated with effortful action control. In our discussion, we reflect on the status quo of physiological research on implementation intentions, methodological and conceptual issues, related research, and propose future

  16. Linear response theory for symmetry improved two particle irreducible effective actions

    Brown, Michael J.; Whittingham, Ian B.; Kosov, Daniel S.

    2016-05-01

    We investigate the linear response of an O (N ) scalar quantum field theory subject to external perturbations using the symmetry-improved two-particle irreducible effective action (SI-2PIEA) formalism [A. Pilaftsis and D. Teresi, Nucl. Phys. B874, 594 (2013)]. Despite satisfactory equilibrium behavior, we find a number of unphysical effects at the linear response level. Goldstone boson field fluctuations are overdetermined, with the only consistent solution being to set the fluctuations and their driving sources to zero, except for momentum modes where the Higgs and Goldstone self-energies obey a particular relationship. Also Higgs field fluctuations propagate masslessly, despite the Higgs propagator having the correct mass. These pathologies are independent of any truncation of the effective action and still exist even if we relax the overdetermining Ward identities, so long as the constraint is formulated O (N ) covariantly. We discuss possible reasons for the apparent incompatibility of the constraints and linear response approximation and possible ways forward.

  17. Mixed Heavy-Light Matching in the Universal One-Loop Effective Action

    Ellis, Sebastian A R; You, Tevong; Zhang, Zhengkang

    2016-01-01

    Recently, a general result for evaluating the path integral at one loop was obtained in the form of the Universal One-Loop Effective Action. It may be used to derive effective field theory operators of dimensions up to six, by evaluating the traces of matrices in this expression, with the mass-dependence encapsulated in the universal coefficients. Here we show that it can account for loops of mixed heavy-light particles in the matching procedure. Our prescription for computing these mixed contributions to the Wilson coefficients is conceptually simple. Moreover it has the advantage of maintaining the universal structure of the effective action, which we illustrate using the example of integrating out a heavy electroweak triplet scalar coupling to a light Higgs doublet. Finally we also identify new structures that were previously neglected in the universal results.

  18. Linear Response Theory for Symmetry Improved Two Particle Irreducible Effective Actions

    Brown, Michael J; Kosov, Daniel S

    2016-01-01

    We investigate the linear response of an O(N) scalar quantum field theory subject to external perturbations using the symmetry improved two particle irreducible effective action formalism [A. Pilaftsis and D. Teresi, Nucl. Phys. B874, 594 (2013)]. Despite satisfactory equilibrium behavior, we find a number of unphysical effects at the linear response level. Goldstone boson field fluctuations are over-determined, with the only consistent solution being to set the fluctuations and their driving sources to zero, except for momentum modes where the Higgs and Goldstone self-energies obey a particular relationship. Also Higgs field fluctuations propagate masslessly, despite the Higgs propagator having the correct mass. These pathologies are independent of any truncation of the effective action and still exist even if we relax the over-determining Ward identities, so long as the constraint is formulated O(N)-covariantly. We discuss possible reasons for the apparent incompatibility of the constraints and linear respo...

  19. Entrainment and task co-representation effects for discrete and continuous action sequences.

    van der Wel, Robrecht P R D; Fu, En

    2015-12-01

    A large body of work has established an influence of other people's actions on our own actions. For example, actors entrain to the movements of others, in studies that typically employ continuous movements. Likewise, studies on co-representation have shown that people automatically co-represent a co-actor's task, in studies that typically employ discrete actions. Here we examined entrainment and co-representation within a single task paradigm. Participants sat next to a confederate while simultaneously moving their right hand back and forth between two targets. We crossed whether or not the participant and the confederate moved over an obstacle and manipulated whether participants generated discrete or continuous movement sequences, while varying the space between the actors and whether the actors could see each other's movements. Participants moved higher when the confederate cleared an obstacle than when he did not. For continuous movements, this effect depended on the availability of visual information, as would be expected on the basis of entrainment. In contrast, the co-actor's task modulated the height of discrete movements, regardless of the availability of visual information, which is consistent with co-representation. Space did not have an effect. These results provide new insights into the interplay between co-representation and entrainment for discrete- and continuous-action tasks. PMID:25911443

  20. The mechanism of the reaction B10 (d,p) B11 at low deuteron energies

    Excitation functions and angular distributions were measured for the four most energetic proton groups from the reaction B10 (d,p) B11 in the deuteron energy range Ed = 0.8 to 2.4 MeV. The excitation functions for all the measured groups showed no noticeable resonance structure. Spectroscopic factors for the states at 0.00 and 4.46 MeV of B11 were extracted from a DWBA analysis of the angular distributions. The average values of the spectroscopic factors were compared with those predicted theoretically. (orig.)

  1. Comment on ''Functional integral for Weyl fermions and the effective action''

    Banerjee, R.; Banerjee, H.

    1989-02-15

    Baaklini's method of obtaining the effective action for Weyl fermions is shown to yield either a gauge-invariant or a gauge-variant form depending on the specific definition employed in the analysis. The structures of the effective action proposed by Baaklini are found to correspond to the standard expressions.

  2. Effectiveness and sustainability of remedial actions for land restoration in Abeokuta urban communities, Ogun State, Nigeria

    Lawal-Adebowale, Okanlade

    2016-04-01

    Land as a major collective human property faces a great deal of threats and eventual degradation from both natural and human causal factors across the globe. But for the central role of land in human's sustenance and quality living, man cannot afford to lose its natural asset and as such takes mitigating or remedial actions to save and restore his land for sustainable use. In view of this, the study assessed the causal factors of land degradation in urban areas of Abeokuta and effectiveness and sustainability of the taken remedial actions to stem the tide of land degradation in the study area. The selected communities were purposively selected based on the observed prevalence of degraded lands in the areas. A qualitative research approach which encompasses observational techniques - participant/field observation, interactive discussion and photographic capturing, was used for collection of data on land degradation in the study area. A combination of phenomenological, inductive thematic analysis and conversation/discourse analysis was employed for data analysis. The results showed land gradients/slopes, rainfall, run-offs/erosion, land-entrenched foot impacts, sand scraping/mining, poor/absence of drainage system and land covers as causal factors of land degradation in the study area. The employed remedial actions for restoration of degraded land included filling of drenches with sand bags, wood logs, bricks and stones, and sand filling. The study though observed that filling of drenches caused by erosion with rubles/stones and construction of drainage were effective remedial actions, good drainage system was presumed to be the most appropriate and sustainable remedial action for land restoration in the study area.

  3. Kappa-symmetry of superstring sigma model and generalized 10d supergravity equations

    Wulff, L

    2016-01-01

    We determine the constraints imposed on the 10d target superspace geometry by the requirement of classical kappa-symmetry of the Green-Schwarz superstring. In the type I case we find that the background must satisfy a generalization of type I supergravity equations. These equations depend on an arbitrary vector X_a and imply the one-loop scale invariance of the GS sigma model. In the special case when X_a is the gradient of a scalar \\phi (dilaton) one recovers the standard type I equations equivalent to the 2d Weyl invariance conditions of the superstring sigma model. In the type II case we find a generalized version of the 10d supergravity equations the bosonic part of which was introduced in arXiv:1511.05795. These equations depend on two vectors \\X_a and K_a subject to 1st order differential relations (with the equations in the NS-NS sector depending only on the combination X_a = \\X_a + K_a). In the special case of K_a=0 one finds that \\X_a=\\d_a \\phi and thus obtains the standard type II supergravity equat...

  4. Exact solution for a quantum field with delta-like interaction effective action and UV renormalization

    Solodukhin, S N

    1999-01-01

    A quantum field described by the field operator $\\Delta_{\\bf a}=\\Delta+{\\bf a}\\delta_\\Sigma$ involving a $\\delta$-like potential is considered. Mathematically, the treatment of the $\\delta$-potential is based on the theory of self-adjoint extension of the unperturbed operator $\\Delta$. We give the general expressions for the resolvent and the heat kernel of the perturbed operator $\\Delta_{\\bf a}$. The main attention is payed to $d=2$ We calculate exactly the heat kernel, Green's functions and the effective action for the operator $\\Delta_{\\bf a}$ in diverse dimensions and for various spaces $\\Sigma$. The renormalization phenomenon for the coupling constant $\\bf a$ of $d=2$ and $d=3$ $\\delta$-potentials is observed. We find the non-perturbative behavior of the effective action with respect to the renormalized coupling ${\\bf a}_{ren}$.

  5. A note on scaling arguments in the effective average action formalism

    Pagani, Carlo

    2016-01-01

    The effective average action (EAA) is a scale dependent effective action where a scale $k$ is introduced via an infrared regulator. The $k-$dependence of the EAA is governed by an exact flow equation to which one associates a boundary condition at a scale $\\mu$. We show that the $\\mu-$dependence of the EAA is controlled by an equation fully analogous to the Callan-Symanzik equation which allows to define scaling quantities straightforwardly. Particular attention is paid to composite operators which are introduced along with new sources. We discuss some simple solutions to the flow equation for composite operators and comment their implications in the case of a local potential approximation.

  6. Supplemental action learning workshops: Understanding the effects of independent and cooperative workshops on students' knowledge

    Morris, Kathryn Michelle

    Community colleges enroll more than half of the undergraduate population in the United States, thereby retaining students of varying demographics with extracurricular demands differing from traditional four-year university students. Often in a collegiate lecture course, students are limited in their abilities to absorb and process information presented by their instructors due to content-specific cognitive gaps between the instructor and the student (Preszler, 2009). Research has shown that implementation of instructor-facilitated action learning workshops as supplemental instruction may help bridge these cognitive gaps allowing better student conceptualization and dissemination of knowledge (Drake, 2011; Fullilove & Treisman, 1990; Preszler, 2009; Udovic, Morris, Dickman, Postlethwait, & Wetherwax, 2002). The purpose of this study was to determine the effects of cooperative action learning workshops and independent action learning workshops on students' knowledge of specified topics within a General Biology I with lab course. The results of this investigation indicate that implementation of an instructor-facilitated action learning workshop did not affect students' knowledge gain; furthermore, attendance of a particular workshop style (independent or cooperative) did not affect students' knowledge gain.

  7. Effect of intrathecal baclofen on the monosynaptic reflex in humans: evidence for a postsynaptic action.

    Azouvi, P; Roby-Brami, A.; Biraben, A; Thiebaut, J B; Thurel, C; Bussel, B

    1993-01-01

    Intrathecal baclofen is a very powerful antispastic agent. Its mechanism of action on the monosynaptic H-reflex in spinal patients was investigated. It could inhibit rapidly and profoundly monosynaptic reflexes in lower limbs, but did not modify Ia vibratory inhibition of the soleus H-reflex. To assess more precisely its effect on Ia afferents, an experimental paradigm using Ia heteronymous facilitation of the soleus H-reflex was used. Intrathecal baclofen did not modify the amount of monosyn...

  8. Radiological effects of Chernobylsk-4 reactor accident and preventive measures to decrease its action

    Analysis of radiological effects of Chernobylsk-4 reactor accident in the USSR and preventive measures to decrease its action are given. Systematic medical examination of population and radiation situation in settlements of contaminated area confirmed efficiency of carried out preventive and protective measures. They include decontamination of settlements, removal of children and pregnant women for summer period rest, regular medical examination of local food-stuff, prohibition of conteminated food-stuff usage

  9. On the application of the effective action approach to amplitudes with reggeon splitting

    Application of the effective action approach to amplitudes with loop integration is studied for collisions on two and three centers with possible gluon emission. A rule is formulated for the integration around pole singularities in the induced vertices which brings the results in agreement with the QCD. It is demonstrated that the amplitudes can be restored from the purely transverse picture by introducing the standard Feynman propagators for intermediate gluons and quarks. (orig.)

  10. Low energy effective action on a self-gravitating D-brane

    Onda, S; Koyama, K; Hayakawa, S; Onda, Sumitada; Shiromizu, Tetsuya; Koyama, Kazuya; Hayakawa, Shoko

    2003-01-01

    Recently the study of braneworld on the self-gravitating D-brane has been initiated and derived the gravitational equation on the brane by holographic and geometrical projection methods. Surprisingly, in common with these two methods, the matter on the brane cannot be the source of the gravity on the brane at leading order. In this paper we will propose the low energy effective action on the D-brane coupled with gravity which derives the same results.