Multi-peaked localized states of DNLS in one and two dimensions

Abstract In this work, we revisit some general results on the dynamics of circular fronts between homogeneous states and the formation of localized structures in two dimensions (2D). We show how the bifurcation diagram of axisymmetric structures localized in radius fits within the framework of collapsed homoclinic snaking. In 2D, owing to curvature effects, the collapse of the snaking structure follows a different scaling that is determined by the so-called nucleation radius. Moreover, in the case of fronts between two symmetry-related states, the precise point in parameter space to which radial snaking collapses is not a ‘Maxwell’ point but is determined by the curvature-driven dynamics only. In this case, the snaking collapses to a ‘zero surface tension’ point. Near this point, the breaking of symmetry between the homogeneous states tilts the snaking diagram. A different scaling law is found for the collapse of the snaking curve in each case. Curvature effects on axisymmetric localized states with internal structure are also discussed, as are cellular structures separated from a homogeneous state by a circular front. While some of these results are well understood in terms of curvature-driven dynamics and front interactions, a proper mathematical description in terms of homoclinic trajectories in a radial spatial dynamics description is lacking.

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SCALING OF RESISTANCE IN THE TWO-DIMENSIONAL ANDERSON TIGHT-BINDING MODEL OF DISORDERED SYSTEMS II

Modern Physics Letters B ◽

10.1142/s0217984994000212 ◽

1994 ◽

Vol 08 (03) ◽

pp. 195-203 ◽

Cited By ~ 4

Author(s):

ANIRBAN SAIN ◽

ABHIJIT MOOKERJEE

Keyword(s):

Disordered Systems ◽

Tight Binding ◽

Weak Localization ◽

Real Space ◽

Two Dimensions ◽

Localized States ◽

Two Dimensional ◽

Binding Model ◽

Algebraic Decay ◽

Band Center

Several workers using different numerical methods have in recent times obtained algebraic decay of wave function amplitudes for localized states at the band center of a two-dimensional disordered system. These include vector recursion,1 direct diagonalization,2 and real space renormalization techniques.3 We modify a version of the combined real space renormalization and vector recursion techniques, including the effect of the random environment on the phase differences between the electronic incoming waves through the different incoming leads, to confirm the algebraic or weak localization at the band center of a random tight-binding Anderson model in two dimensions.

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The tangled web of agency

Behavioral and Brain Sciences ◽

10.1017/s0140525x17001170 ◽

2018 ◽

Vol 41 ◽

Author(s):

Alain Pe-Curto ◽

Julien A. Deonna ◽

David Sander

Keyword(s):

Two Dimensions ◽

Bad Company

AbstractWe characterize Doris's anti-reflectivist, collaborativist, valuational theory along two dimensions. The first dimension is socialentanglement, according to which cognition, agency, and selves are socially embedded. The second dimension isdisentanglement, the valuational element of the theory that licenses the anchoring of agency and responsibility in distinct actors. We then present an issue for the account: theproblem of bad company.

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A transmission electron microscopic study of structural transitions in fast ionic conductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125713 ◽

1987 ◽

Vol 45 ◽

pp. 156-157

Author(s):

R. B. Queenan ◽

P. K. Davies

Keyword(s):

Optical Properties ◽

Ionic Conduction ◽

Recent Observation ◽

Ionic Conductivities ◽

Sodium Aluminate ◽

Two Dimensions ◽

Ionic Conductors ◽

Electron Microscopic ◽

Transmission Electron ◽

Trivalent Cations

Na ß“-alumina (Na1.67Mg67Al10.33O17) is a non-stoichiometric sodium aluminate which exhibits fast ionic conduction of the Na+ ions in two dimensions. The Na+ ions can be exchanged with a variety of mono-, di-, and trivalent cations. The resulting exchanged materials also show high ionic conductivities.Considerable interest in the Na+-Nd3+-ß“-aluminas has been generated as a result of the recent observation of lasing in the pulsed and cw modes. A recent TEM investigation on a 100% exchanged Nd ß“-alumina sample found evidence for the intergrowth of two different structure types. Microdiffraction revealed an ordered phase coexisting with an apparently disordered phase, in which the cations are completely randomized in two dimensions. If an order-disorder transition is present then the cooling rates would be expected to affect the microstructures of these materials which may in turn affect the optical properties. The purpose of this work was to investigate the affect of thermal treatments upon the micro-structural and optical properties of these materials.

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Laser Scanning Confocal Microscopy and Three-Dimesnsional Reconstruction of the Mitotic Spindles of Unequally Dividing Embryonic Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158376 ◽

1990 ◽

Vol 48 (3) ◽

pp. 166-167

Author(s):

J. Holy ◽

G. Schatten

Keyword(s):

Confocal Microscopy ◽

Mitotic Spindle ◽

Laser Scanning ◽

Three Dimensional ◽

Laser Scanning Confocal Microscopy ◽

Two Dimensions ◽

Embryonic Cells ◽

Mitotic Spindles ◽

Cleavage Division ◽

Scanning Confocal Microscopy

One of the classic limitations of light microscopy has been the fact that three dimensional biological events could only be visualized in two dimensions. Recently, this shortcoming has been overcome by combining the technologies of laser scanning confocal microscopy (LSCM) and computer processing of microscopical data by volume rendering methods. We have employed these techniques to examine morphogenetic events characterizing early development of sea urchin embryos. Specifically, the fourth cleavage division was examined because it is at this point that the first morphological signs of cell differentiation appear, manifested in the production of macromeres and micromeres by unequally dividing vegetal blastomeres.The mitotic spindle within vegetal blastomeres undergoing unequal cleavage are highly polarized and develop specialized, flattened asters toward the micromere pole. In order to reconstruct the three-dimensional features of these spindles, both isolated spindles and intact, extracted embryos were fluorescently labeled with antibodies directed against either centrosomes or tubulin.

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Instrumental and Ideological Union Commitment: Longitudinal Assessment of Construct Validity

European Journal of Psychological Assessment ◽

10.1027//1015-5759.17.2.98 ◽

2001 ◽

Vol 17 (2) ◽

pp. 98-111 ◽

Cited By ~ 1

Author(s):

Anders Sjöberg ◽

Magnus Sverke

Keyword(s):

Construct Validity ◽

Temporal Stability ◽

Strong Support ◽

Internal Consistency Reliability ◽

Measurement Model ◽

Two Dimensions ◽

Model Parameters ◽

Longitudinal Assessment ◽

Union Commitment ◽

Union Participation

Summary: Previous research has identified instrumentality and ideology as important aspects of member attachment to labor unions. The present study evaluated the construct validity of a scale designed to reflect the two dimensions of instrumental and ideological union commitment using a sample of 1170 Swedish blue-collar union members. Longitudinal data were used to test seven propositions referring to the dimensionality, internal consistency reliability, and temporal stability of the scale as well as postulated group differences in union participation to which the scale should be sensitive. Support for the hypothesized factor structure of the scale and for adequate reliabilities of the dimensions was obtained and was also replicated 18 months later. Tests for equality of measurement model parameters and test-retest correlations indicated support for the temporal stability of the scale. In addition, the results were consistent with most of the predicted differences between groups characterized by different patterns of change/stability in union participation status. The study provides strong support for the construct validity of the scale and indicates that it can be used in future theory testing on instrumental and ideological union commitment.

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The Prediction of Problem-Solving Assessed Via Microworlds

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000263 ◽

2016 ◽

Vol 32 (4) ◽

pp. 298-306 ◽

Cited By ~ 7

Author(s):

Samuel Greiff ◽

Katarina Krkovic ◽

Jarkko Hautamäki

Keyword(s):

Working Memory ◽

Problem Solving ◽

Complex Problem ◽

Two Dimensions ◽

Assessment Instruments ◽

Complex Problem Solving ◽

Visual Spatial ◽

Rule Knowledge ◽

Rule Application ◽

Fluid Reasoning

Abstract. In this study, we explored the network of relations between fluid reasoning, working memory, and the two dimensions of complex problem solving, rule knowledge and rule application. In doing so, we replicated the recent study by Bühner, Kröner, and Ziegler (2008) and the structural relations investigated therein [ Bühner, Kröner, & Ziegler, (2008) . Working memory, visual-spatial intelligence and their relationship to problem-solving. Intelligence, 36, 672–680]. However, in the present study, we used different assessment instruments by employing assessments of figural, numerical, and verbal fluid reasoning, an assessment of numerical working memory, and a complex problem solving assessment using the MicroDYN approach. In a sample of N = 2,029 Finnish sixth-grade students of which 328 students took the numerical working memory assessment, the findings diverged substantially from the results reported by Bühner et al. Importantly, in the present study, fluid reasoning was the main source of variation for rule knowledge and rule application, and working memory contributed only a little added value. Albeit generally in line with previously conducted research on the relation between complex problem solving and other cognitive abilities, these findings directly contrast the results of Bühner et al. (2008) who reported that only working memory was a source of variation in complex problem solving, whereas fluid reasoning was not. Explanations for the different patterns of results are sought, and implications for the use of assessment instruments and for research on interindividual differences in complex problem solving are discussed.

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Development of the Fear of Intimacy Components Questionnaire (FICQ)

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000238 ◽

2015 ◽

Vol 31 (4) ◽

pp. 302-309 ◽

Cited By ~ 3

Author(s):

Maria Pedro Sobral ◽

Maria Emília Costa

Keyword(s):

Convergent Validity ◽

Discriminant Validity ◽

Two Dimensions ◽

Dimensional Structure ◽

Future Research ◽

Fear Of Intimacy ◽

Confirmatory Factor Analyses ◽

New Instrument ◽

Confirmatory Factor ◽

Test Retest Reliability

Abstract. We developed a new instrument designed to measure fear of intimacy in romantic relationships. We suggest assessing fear of intimacy through two dimensions: self-revelation and dependence. The Fear of Intimacy Components Questionnaire (FICQ) was validated across three studies in which a 10-item solution systematically emerged. Consistently with a two component perspective, a two-factor solution fitted data the best: fear of losing the self (FLS) and fear of losing the other (FLO). Qualitative analyses verified content validity. Exploratory and confirmatory factor analyses tested the factor structure. Multigroup analyses supported the structural invariance across gender, age, and relationship status. Both factors showed adequate discriminant validity and internal consistency, and good 3-week period test-retest reliability. Associations between the FICQ and insecure attachment orientations demonstrated convergent validity. The association between the FICQ and relationship satisfaction above and beyond a preexisting measure offered criterion validity. By going beyond traditional self-revelation-focused conception of fear of intimacy, that is, by proposing a bi-dimensional structure to fear of intimacy, we believe that this new measure will contribute to future research on fear of intimacy.

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The “Big Two” in Political Communication

Social Psychology ◽

10.1027/1864-9335/a000141 ◽

2013 ◽

Vol 44 (2) ◽

pp. 117-128 ◽

Cited By ~ 14

Author(s):

Mauro Bertolotti ◽

Patrizia Catellani ◽

Karen M. Douglas ◽

Robbie M. Sutton

Keyword(s):

Political Communication ◽

Experimental Studies ◽

Two Dimensions ◽

Political Sophistication

In two experimental studies (conducted in Britain and Italy), participants read about a politician answering to leadership- versus morality-related allegations using either downward counterfactuals (“things could have been worse, if ...”) or upward counterfactuals (“things could have been better, if ...”). Downward messages increased the perception of the politician’s leadership, while both downward and upward messages increased morality perception. Political sophistication moderated the effect of message direction, with downward messages increasing perceived morality in low sophisticates and upward messages increasing perceived morality in high sophisticates. In the latter group, the acknowledgment of an intent to take responsibility mediated morality judgment. Results were consistent across different countries, highlighting previously unexplored effects of communication on the perception of the “Big Two” dimensions.

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Positive First or Negative First?

Methodology ◽

10.1027/1614-2241/a000013 ◽

2010 ◽

Vol 6 (3) ◽

pp. 118-127 ◽

Cited By ~ 17

Author(s):

Dagmar Krebs ◽

Juergen H.P. Hoffmeyer-Zlotnik

Keyword(s):

Job Characteristics ◽

Two Dimensions ◽

Response Behavior ◽

Point Scale ◽

Response Scale ◽

Job Motivation ◽

Ballot Design ◽

Subjective Importance ◽

Scale Format ◽

Scale Types

To examine whether starting a response scale with the positive or the negative categories affects response behavior, a split-ballot design using reverse forms of an 8-point scale assessing the subjective importance of job characteristics was used. Response behavior varied according to the scale format employed. Responses were more positive on the scale starting with the category “very important” (split 2). By contrast, the scale starting with the category “not at all important” (split 1) did not elicit more negative responses, but rather less positive ones. However, differences in response behavior did not systematically reflect the direction of the respective scales. Starting with the differences between the two split versions, the factorial structure of indicators assessing two dimensions of job motivation was tested for each scale type separately and then for both scale types simultaneously. Finally, models placing increasingly severe equality constraints on both scale types were tested. The paper concludes with a discussion of the results and desiderata for further research.

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