1,074 research outputs found

    The Corporate Income Tax: international trends and options for fundamental reform

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    This paper discusses the future of the corporate income tax in an integrating world economy. The first part of the paper reviews some important trends in corporate taxation across the OECD area. The second part discusses the role of the corporation tax, laying out guidelines for corporate tax reform and considering some alternatives to existing corporate income taxes. In discussing options for fundamental reform, two sets of concerns are addressed. The first represents the traditional aims of a tax on corporate income. Essentially the traditional aim has been to design a tax system which raises revenue as efficiently as possible - that is, which minimises distortions to the location and scale of investment, to the sources and uses of finance, and to the choice of legal form. These distortions have been the subject of study for many years, and many proposals for reform have been made. One of the most popular and enduring ideas has been to tax only economic rent: in a traditional framework such a tax would not be expected to have any effect on investment or financing decisions.There is also a second set of concerns. Part of this concern has also been the subject of study for many years - the relationship between the personal and corporate sectors, and in particular, the possibility of tax avoidance by shifting income between the two sectors.world economy, corporate income tax, corporation tax, corporate tax reform, alternatives, distortions, economic rent, tax avoidance, Devereux, Birch Sørensen

    Mesoscopic atomic entanglement for precision measurements beyond the standard quantum limit

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    Squeezing of quantum fluctuations by means of entanglement is a well recognized goal in the field of quantum information science and precision measurements. In particular, squeezing the fluctuations via entanglement between two-level atoms can improve the precision of sensing, clocks, metrology, and spectroscopy. Here, we demonstrate 3.4 dB of metrologically relevant squeezing and entanglement for ~ 10^5 cold cesium atoms via a quantum nondemolition (QND) measurement on the atom clock levels. We show that there is an optimal degree of decoherence induced by the quantum measurement which maximizes the generated entanglement. A two-color QND scheme used in this paper is shown to have a number of advantages for entanglement generation as compared to a single color QND measurement.Comment: 6 pages+suppl, PNAS forma

    On the Coexistence of Diagonal and off-Diagonal Long-Range Order, a Monte Carlo Study

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    The zero temperature properties of interacting 2 dimensional lattice bosons are investigated. We present Monte Carlo data for soft-core bosons that demonstrate the existence of a phase in which crystalline long-range order and off-diagonal long-range order (superfluidity) coexist. We comment on the difference between hard and soft-core bosons and compare our data to mean-field results that predict a larger coexistence region. Furthermore, we determine the critical exponents for the various phase transitions.Comment: 7 pages and 8 figures appended in postscript, KA-TFP-93-0

    S(k) for Haldane Gap Antiferromagnets: Large-scale Numerical Results vs. Field Theory and Experiment

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    The structure function, S(k), for the s=1, Haldane gap antiferromagnetic chain, is measured accurately using the recent density matrix renormalization group method, with chain-length 100. Excellent agreement with the nonlinear σ\sigma model prediction is obtained, both at kπk\approx \pi where a single magnon process dominates and at k0k\approx 0 where a two magnon process dominates. We repeat our calculation with crystal field anisotropy chosen to model NENP, obtaining good agreement with both field theory predictions and recent experiments. Correlation lengths, gaps and velocities are determined for both polarizations.Comment: 11 pages, 3 postscript figures included, REVTEX 3.0, UBCTP-93-02

    Equal Time Correlations in Haldane Gap Antiferromagnets

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    The S=1S=1 antiferromagnetic Heisenberg chain both with and without single ion anisotropy is studied. Using the recently proposed density matrix renormalization group technique we calculate the energy gaps as well as several different correlation functions. The two gaps, Δ,Δ\Delta_{||}, \Delta_\perp, along with associated correlation lengths and velocities are determined. The numerical results are shown to be in good agreement with theoretical predictions derived from the nonlinear sigma model and a free boson model. We also study the S=1/2S=1/2 excitations that occur at the ends of open chains; in particular we study the behavior associated with open boundary conditions, using a model of S=1/2S=1/2 spins coupled to the free bosons.Comment: 32 pages, uufiles encoded REVTEX 3.0, 19 postscript figures included, UBCTP-93-02

    Preoperative apolipoprotein CI levels correlate positively with the proinflammatory response in patients experiencing endotoxemia following elective cardiac surgery

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    Objective: Experimental models show that apolipoprotein CI (apoCI) binds and enhances the inflammatory response to endotoxin. We studied in patients undergoing cardiopulmonary bypass surgery (CPB) and experiencing endotoxemia during reperfusion whether plasma apoCI levels correlate with the inflammatory response and perioperative cytokine release. Design: Prospective, observational, clinical cohort study. Setting: Operating room (OR) and intensive care unit (ICU) of a university hospital. Patients: One hundred fifty-nine consecutive patients > 18 years of age (66% males (n = 105), median age 65 and 67 years for males and females, respectively) undergoing elective cardiothoracic surgery with cardiopulmonary bypass. Interventions: None. Measurements: Baseline apoCI, apoCIII, total cholesterol and triglyceride levels, and perioperative endotoxin and TNF-α levels were determined. Results: High preoperative plasma apoCI, but not apoCIII, levels were associated (p < 0.05) with increased perioperative levels of TNF-α in patients experiencing endotoxemia. This association was not observed in patients without endotoxemia. Conclusion: High plasma apoCI is positively related to proinflammatory response in patients experiencing endotoxemia and confirms the observations in animal models. © 2008 The Author(s)
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