2,022 research outputs found

    Spaceborne memory organization, an associative data acquisition system, phase II Final report, Apr. - Dec. 1966

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    Spaceborne memory organization, associative data acquisition system design, and data compression technique

    Cognitive heuristics in borderline personality disorder across treatment: A longitudinal non-parametric analysis.

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    The development of a constructive therapeutic alliance may represent an important feature of interpersonal adaptation in clients with Borderline Personality Disorder (BPD). The present study explores cognitive heuristics as dynamic features of change in relationship with the therapeutic alliance in the treatment of BPD. In total, N = 60 clients with BPD, are included in the present study. In the context of brief therapy, the therapeutic alliance (WAI) is assessed from the client and the therapist perspectives after each therapy session; cognitive heuristics are assessed three times (CERS). The data analyses are on the basis of non-parametric clusters (kml3d) linked with the therapeutic alliance. The results showed that clusters of cognitive heuristics trajectories are linked with the client's therapeutic alliance (t(55) = 2.30, p = .03), but they remained unrelated with the evolution of the therapist's alliance. These results are discussed with regard to the interpersonal adaptiveness of cognitive heuristics in the context of BPD undergoing treatment

    Spontaneous Scalarization and Boson Stars

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    We study spontaneous scalarization in Scalar-Tensor boson stars. We find that scalarization does not occur in stars whose bosons have no self-interaction. We introduce a quartic self-interaction term into the boson Lagrangian and show that when this term is large, scalarization does occur. Strong self-interaction leads to a large value of the compactness (or sensitivity) of the boson star, a necessary condition for scalarization to occur, and we derive an analytical expression for computing the sensitivity of a boson star in Brans-Dicke theory from its mass and particle number. Next we comment on how one can use the sensitivity of a star in any Scalar-Tensor theory to determine how its mass changes when it undergoes gravitational evolution. Finally, in the Appendix, we derive the most general form of the boson wavefunction that minimises the energy of the star when the bosons carry a U(1) charge.Comment: 23 pages, 5 postscript figures. Typing errors corrected. Includes some new text that relates the paper to several previous results. Accepted for publication in PR

    Secondary literacy across the curriculum: Challenges and possibilities

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    This paper discusses the challenges and possibilities attendant upon successfully implementing literacy across the curriculum initiatives – or ‘school language policies’ as they have come to be known - particularly at the secondary or high school level. It provides a theoretical background to these issues, exploring previous academic discussions of school language policies, and highlights key areas of concern as well as opportunity with respect to school implementation of such policies. As such, it provides a necessary conceptual background to the subsequent papers in this special issue, which focus upon the Secondary Schools’ Literacy Initiative (SSLI) – a New Zealand funded programme that aims to establish cross-curricular language and literacy policies in secondary schools

    Boson Stars in General Scalar-Tensor Gravitation: Equilibrium Configurations

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    We study equilibrium configurations of boson stars in the framework of general scalar-tensor theories of gravitation. We analyse several possible couplings, with acceptable weak field limit and, when known, nucleosynthesis bounds, in order to work in the cosmologically more realistic cases of this kind of theories. We found that for general scalar-tensor gravitation, the range of masses boson stars might have is comparable with the general relativistic case. We also analyse the possible formation of boson stars along different eras of cosmic evolution, allowing for the effective gravitational constant far out form the star to deviate from its current value. In these cases, we found that the boson stars masses are sensitive to this kind of variations, within a typical few percent. We also study cases in which the coupling is implicitly defined, through the dependence on the radial coordinate, allowing it to have significant variations in the radius of the structure.Comment: 19 pages in latex, 3 figures -postscript- may be sent via e-mail upon reques

    Dynamical evolution of boson stars in Brans-Dicke theory

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    We study the dynamics of a self-gravitating scalar field solitonic object (boson star) in the Jordan-Brans-Dicke (BD) theory of gravity. We show dynamical processes of this system such as (i) black hole formation of perturbed equilibrium configuration on an unstable branch; (ii) migration of perturbed equilibrium configuration from the unstable branch to stable branch; (iii) transition from excited state to a ground state. We find that the dynamical behavior of boson stars in BD theory is quite similar to that in general relativity (GR), with comparable scalar wave emission. We also demonstrate the formation of a stable boson star from a Gaussian scalar field packet with flat gravitational scalar field initial data. This suggests that boson stars can be formed in the BD theory in much the same way as in GR.Comment: 13 pages by RevTeX, epsf.sty, 16 figures, comments added, refs updated, to appear in Phys. Rev.

    Charged Scalar-Tensor Boson Stars: Equilibrium, Stability and Evolution

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    We study charged boson stars in scalar-tensor (ST) gravitational theories. We analyse the weak field limit of the solutions and analytically show that there is a maximum charge to mass ratio for the bosons above which the weak field solutions are not stable. This charge limit can be greater than the GR limit for a wide class of ST theories. We numerically investigate strong field solutions in both the Brans Dicke and power law ST theories. We find that the charge limit decreases with increasing central boson density. We discuss the gravitational evolution of charged and uncharged boson stars in a cosmological setting and show how, at any point in its evolution, the physical properties of the star may be calculated by a rescaling of a solution whose asymptotic value of the scalar field is equal to its initial asymptotic value. We focus on evolution in which the particle number of the star is conserved and we find that the energy and central density of the star decreases as the cosmological time increases. We also analyse the appearance of the scalarization phenomenon recently discovered for neutron stars configurations and, finally, we give a short discussion on how making the correct choice of mass influences the argument over which conformal frame, the Einstein frame or the Jordan frame, is physical.Comment: RevTeX, 27 pages, 9 postscript figures. Minor revisions and updated references. Accepted for publication in Phys. Rev.

    Boson stars in massive dilatonic gravity

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    We study equilibrium configurations of boson stars in the framework of a class scalar-tensor theories of gravity with massive gravitational scalar (dilaton). In particular we investigate the influence of the mass of the dilaton on the boson star structure. We find that the masses of the boson stars in presence of dilaton are close to those in general relativity and they are sensitive to the ratio of the boson mass to the dilaton mass within a typical few percent. It turns out also that the boson star structure is mainly sensitive to the mass term of the dilaton potential rather to the exact form of the potential.Comment: 9 pages, latex, 9 figures, one figure dropped, new comments added, new references added, typos correcte

    Gender, age and the MBA: An analysis of extrinsic and intrinsic career benefits

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    Against the background of an earlier UK study, this paper presents the findings of a Canadian based survey of career benefits from the MBA. Results indicate firstly that gender and age interact to influence perceptions of career outcomes (young men gain most in terms of extrinsic benefits of career change and pay), and secondly that both men and women gain intrinsic benefits from the MBA. However, intrinsic benefits vary by gender: men in the study were more likely to say they gained confidence from having a fuller skill set while women were more likely to say they gained confidence from feelings of self worth; men emphasised how they had learned to give up control while women argued that they had gained a ‘voice’ in the organization. The role of the MBA in career self- management and the acquisition of key skills are examined as well as the implications for the design of programmes in meeting the varied need of men and women in different age groups
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