1,687 research outputs found

    Child support judgments: comparing public policy to the public's policy

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    Any child support regime necessarily makes policy choices about how parental income should be shared between the two parental households. Those choices involve balancing the claims of the child, the claims of the custodial parent for help with the expense of providing for the child, and the claims of the support obligor for autonomy in deciding how to spend his own earnings. That balancing task is complicated by the fact that the child and the custodial parent necessarily share a living standard, so that any child support transfer, large or small, will unavoidably benefit the custodial parent as well as the child. This article reports the findings of an empirical study designed to reveal how the British public believe this balance should be struck. It then compares the public’s preferred policies to the policy choices implicit in the current UK child support schedule. It concludes that there are important gaps between the two, and recommends that consideration be given to amending the current UK law to better align it with the public’s values on these matters

    History dependent magnetoresistance in lightly doped La_{2-x}Sr_{x}CuO_{4} thin films

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    The in-plane magnetoresistance (MR) in atomically smooth La_{2-x}Sr_{x}CuO_{4} thin films grown by molecular-beam-epitaxy was measured in magnetic fields B up to 9 T over a wide range of temperatures T. The films, with x=0.03 and x=0.05, are insulating, and the positive MR emerges at T<4 K. The positive MR exhibits glassy features, including history dependence and memory, for all orientations of B. The results show that this behavior, which reflects the onset of glassiness in the dynamics of doped holes, is a robust feature of the insulating state.Comment: 4 pages, 4 figures, International School and Workshop on Electronic Crystals (ECRYS-2011); to appear in Physica

    Primary accumulation in the Soviet transition

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    The Soviet background to the idea of primary socialist accumulation is presented. The mobilisation of labour power and of products into public sector investment from outside are shown to have been the two original forms of the concept. In Soviet primary accumulation the mobilisation of labour power was apparently more decisive than the mobilisation of products. The primary accumulation process had both intended and unintended results. Intended results included bringing most of the economy into the public sector, and industrialisation of the economy as a whole. Unintended results included substantial economic losses, and the proliferation of coercive institutions damaging to attainment of the ultimate goal - the building of a communist society

    Coulomb blockade and quantum tunnelling in the low-conductivity phase of granular metals

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    We study the effects of Coulomb interaction and inter-grain quantum tunnelling in an array of metallic grains using the phase-functional approach for temperatures TT well below the charging energy EcE_{c} of individual grains yet large compared to the level spacing in the grains. When the inter-grain tunnelling conductance g1g\gg1, the conductivity σ\sigma in dd dimensions decreases logarithmically with temperature (σ/σ0112πgdln(gEc/T)\sigma/\sigma_{0}\sim1-\frac{1}{2\pi gd}\ln(gE_{c}/T)), while for g0g\to0, the conductivity shows simple activated behaviour (σexp(Ec/T)\sigma \sim \exp(-E_c/T)). We show, for bare tunnelling conductance g1g \gtrsim 1, that the parameter γg(12/(gπ)ln(gEc/T))\gamma \equiv g(1-2/(g\pi)\ln(gE_{c}/T)) determines the competition between charging and tunnelling effects. At low enough temperatures in the regime 1γ1/βEc1\gtrsim \gamma \gg 1/\sqrt{\beta E_{c}}, a charge is shared among a finite number N=(Ec/T)/ln(π/2γz)N=\sqrt{(E_{c}/T)/\ln(\pi/2\gamma z)} of grains, and we find a soft activation behaviour of the conductivity, σz1exp(2(Ec/T)ln(π/2γz))\sigma\sim z^{-1}\exp(-2\sqrt{(E_{c}/T)\ln(\pi/2\gamma z)}), where zz is the effective coordination number of a grain.Comment: 11 pages REVTeX, 3 Figures. Appendix added, replaced with published versio

    Model-Based Definition Accelerates Product Life Cycle in Manufacturing and Inspection Phase - Experiment of Machined One-Off Production

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    The paper focuses on comparative experiment on manufacturing and inspection of two different prismatic one-off parts, which have different complexity. Our experiment shows that transforming product definition method from the Drawing Centric Definition (DCD) to the Model Centric Definition (MCD) enables 28%-29% time savings in manufacturing and inspection phases of machined one-off part's life cycle. Furthermore, transition from MCD to Model-Based Definition (MBD) enables 5%-9% time savings, respectively. Applying of MBD enables more time savings in complex part compared to a less complex part.publishedVersionPeer reviewe

    Electron-Phonon Interaction and Ultrasonic Attenuation in the Ruthenate and Cuprate superconductors

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    This article derives an electron-phonon interaction suitable for interpreting ultrasonic attenuation measurements in the ruthenate and cuprate superconductors. The huge anisotropy found experimentally (Lupien et al., 2001) in Sr2RuO4 in the normal state is accounted for in terms of the layered square-lattice structure of Sr2RuO4, and the dominant contribution to the attenuation in Sr2RuO4 is found to be due to electrons in the gamma band. The experimental data in the superconducting state is found to be inconsistent with vertical lines nodes in the gap in either (100) or (110) planes. Also, a general method, based on the use of symmetry, is developed to allow for the analysis of ultrasonic attenuation experiments in superconductors in which the electronic band structure is complicated or not known. Our results, both for the normal-state anisotropy, and relating to the positions of the gap nodes in the superconducting state, are different from those obtained from analyses using a more traditional model for the electron-phonon interaction in terms of an isotropic electron stress tensor. Also, a brief discussion of the ultrasonic attenuation in UPt3 is given.Comment: 12 pages. Comments have been added to the original version of this article showing how, for the ultrasonic attenuation for a hexagonal crystal (which must be isotropic with respect to rotations about the c axis) our approach reproduces the results of the traditional isotropic electron stress tensor mode

    Interlayer pair tunneling and gap anisotropy in YBa2_2Cu3_3O7δ_{7-\delta}

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    Recent ARPES measurement observed a large abab-axis gap anisotropy, Δ(0,π)/Δ(π,0)=1.5\Delta(0,\pi)/\Delta(\pi,0)=1.5, in clean YBa2_2Cu3_3O7δ_{7-\delta}. This indicates that some sub-dominant component may exist in the dx2y2d_{x^2-y^2}-wave dominant gap. We propose that the interlayer pairing tunneling contribution can be determined through the investigation of the order parameter anisotropy. Their potentially observable features in transport and spin dynamics are also studied.Comment: 4 pages, 3 figure

    The QUEST RR Lyrae Survey: Confirmation of the Clump at 50 kpc and Other Over-Densities in the Outer Halo

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    We have measured the periods and light curves of 148 RR Lyrae variables from V=13.5 to 19.7 from the first 100 sq. degrees of the QUEST RR Lyrae survey. Approximately 55% of these stars belong to the clump of stars detected earlier by the Sloan Digital Sky Survey. According to our measurements, this feature has ~10 times the background density of halo stars, spans at least 37.5 deg by 3.5 deg in right ascension and declination (>=30 by >=3 kpc), lies ~50 kpc from the Sun, and has a depth along the line of sight of ~5 kpc (1 sigma). These properties are consistent with the recent models that suggest it is a tidal stream from the Sgr dSph galaxy. The mean period of the type ab variables, 0.58 d, is also consistent. In addition, we have found two smaller over-densities in the halo, one of which may be related to the globular cluster Pal 5.Comment: 12 pages (including 4 figures). Accepted for publication in the ApJ Letter

    Design, expression and characterization of mutants of fasciculin optimized for interaction with its target, acetylcholinesterase

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    Predicting mutations that enhance protein–protein affinity remains a challenging task, especially for high-affinity complexes. To test our capability to improve the affinity of such complexes, we studied interaction of acetylcholinesterase with the snake toxin, fasciculin. Using the program ORBIT, we redesigned fasciculin's sequence to enhance its interactions with Torpedo californica acetylcholinesterase. Mutations were predicted in 5 out of 13 interfacial residues on fasciculin, preserving most of the polar inter-molecular contacts seen in the wild-type toxin/enzyme complex. To experimentally characterize fasciculin mutants, we developed an efficient strategy to over-express the toxin in Escherichia coli, followed by refolding to the native conformation. Despite our predictions, a designed quintuple fasciculin mutant displayed reduced affinity for the enzyme. However, removal of a single mutation in the designed sequence produced a quadruple mutant with improved affinity. Moreover, one designed mutation produced 7-fold enhancement in affinity for acetylcholinesterase. This led us to reassess our criteria for enhancing affinity of the toxin for the enzyme. We observed that the change in the predicted inter-molecular energy, rather than in the total energy, correlates well with the change in the experimental free energy of binding, and hence may serve as a criterion for enhancement of affinity in protein–protein complexes

    Theory of tunneling conductance for normal metal/insulator/triplet superconductor junctions

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    Tunneling conductance spectra of normal metal/insulator/triplet superconductor junctions are investigated theoretically. As triplet paring states we select several types of symmetries that are promising candidates for the superconducting states in UPt3_{3} and in Sr2_{2}RuO4_{4}. The calculated conductance spectra are sensitive to the orientation of the junction which reflects the anisotropy of the pairing states. They show either zero-bias conductance peaks or gap-like structures depending on the orientation of the junctions. The existence of a residual density of states, peculiar to nonunitary states, is shown to have a significant influence on the properties of the conductance spectra. Present results serve as a guidefor the experimental determination of the symmetry of the pair potentials in UPt3_{3} and Sr2_{2}RuO4_{4}.Comment: 10 pages, 11 eps figures, J.Phys.Soc.Jpn.67,No.9(1998
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