Wavefunctions for the Luttinger liquid

Standard bosonization techniques lead to phonon-like excitations in a Luttinger liquid (LL), reflecting the absence of Landau quasiparticles in these systems. Yet in addition to the above excitations some LL are known to possess solitonic states carrying fractional quantum numbers (e.g. the spin 1/2 Heisenberg chain). We have reconsidered the zero modes in the low-energy spectrum of the gaussian boson LL hamiltonian both for fermionic and bosonic LL: in the spinless case we find that two elementary excitations carrying fractional quantum numbers allow to generate all the charge and current excited states of the LL. We explicitly compute the wavefunctions of these two objects and show that one of them can be identified with the 1D version of the Laughlin quasiparticle introduced in the context of the Fractional Quantum Hall effect. For bosons, the other quasiparticle corresponds to a spinon excitation. The eigenfunctions of Wen's chiral LL hamiltonian are also derived: they are quite simply the one dimensional restrictions of the 2D bulk Laughlin wavefunctions.Comment: 5 pages; accepted for publication in EPR B, Rapid Note

Fractional excitations in the Luttinger liquid

We reconsider the spectrum of the Luttinger liquid (LL) usually understood in terms of phonons (density fluctuations), and within the context of bosonization we give an alternative representation in terms of fractional states. This allows to make contact with Bethe Ansatz which predicts similar fractional states. As an example we study the spinon operator in the absence of spin rotational invariance and derive it from first principles: we find that it is not a semion in general; a trial Jastrow wavefunction is also given for that spinon state. Our construction of the new spectroscopy based on fractional states leads to several new physical insights: in the low-energy limit, we find that the $S_{z}=0$ continuum of gapless spin chains is due to pairs of fractional quasiparticle-quasihole states which are the 1D counterpart of the Laughlin FQHE quasiparticles. The holon operator for the Luttinger liquid with spin is also derived. In the presence of a magnetic field, spin-charge separation is not realized any longer in a LL: the holon and the spinon are then replaced by new fractional states which we are able to describe.Comment: Revised version to appear in Physical Review B. 27 pages, 5 figures. Expands cond-mat/9905020 (Eur.Phys.Journ.B 9, 573 (1999)

Low-Energy Properties of a One-dimensional System of Interacting bosons with Boundaries

The ground state properties and low-lying excitations of a (quasi) one-dimensional system of longitudinally confined interacting bosons are studied. This is achieved by extending Haldane's harmonic-fluid description to open boundary conditions. The boson density, one-particle density matrix, and momentum distribution are obtained accounting for finite-size and boundary effects. Friedel oscillations are found in the density. Finite-size scaling of the momentum distribution at zero momentum is proposed as a method to obtain from the experiment the exponent that governs phase correlations. The strong correlations between bosons induced by reduced dimensionality and interactions are displayed by a Bijl-Jastrow wave function for the ground state, which is also derived.Comment: Final published version. Minor changes with respect to the previous versio

Implications of bleeding in acute coronary syndrome and percutaneous coronary intervention

The advent of potent antiplatelet and antithrombotic agents over the past decade has resulted in significant improvement in reducing ischemic events in acute coronary syndrome (ACS). However, the use of antiplatelet and antithrombotic combination therapy, often in the settings of percutaneous coronary intervention (PCI), has led to an increase in the risk of bleeding. In patients with non-ST elevation myocardial infarction treated with antithrombotic agents, bleeding has been reported to occur in 0.4%–10% of patients, whereas in patients undergoing PCI, periprocedural bleeding occurs in 2.2%–14% of cases. Until recently, bleeding was considered an intrinsic risk of antithrombotic therapy, and efforts to reduce bleeding have received little attention. There have been increasing data demonstrating that bleeding is associated with adverse outcomes, including myocardial infarction, stroke, and death. Therefore, it is imperative to optimize patient outcomes by adopting pharmacological and nonpharmacological strategies to minimize bleeding while maximizing treatment efficacy. In this paper, we present a review of the bleeding classifications used in large-scale clinical trials in patients with ACS and those undergoing PCI treated with antiplatelets and antithrombotic agents, adverse outcomes, particularly mortality associated with bleeding complications, and suggested predictive risk factors. Potential mechanisms of the association between bleeding and mortality and strategies to reduce bleeding complications are also discussed

2017 update on pain management in patients with chronic kidney disease

The prevalence of pain has been reported to be \u3e60–70% among patients with advanced and end-stage kidney disease. Although the underlying etiologies of pain may vary, pain per se has been linked to lower quality of life and depression. The latter is of great concern given its known association with reduced survival among patients with end-stage kidney disease.We herein discuss and update the management of pain in patients with chronic kidney disease with and without requirement for renal replacement therapy with the focus on optimizing pain control while minimizing therapy-induced complications

Distinct subpopulations of enteric neuronal progenitors defined by time of development, sympathoadrenal lineage markers and Mash-1-dependence

Enteric and sympathetic neurons have previously been proposed to be lineally related. We present independent lines of evidence that suggest that enteric neurons arise from at least two lineages, only one of which expresses markers in common with sympathoadrenal cells. In the rat, sympathoadrenal markers are expressed, in the same order as in sympathetic neurons, by a subset of enteric neuronal precursors, which also transiently express tyrosine hydroxylase. If this precursor pool is eliminated in vitro by complement-mediated lysis, enteric neurons continue to develop; however, none of these are serotonergic. In the mouse, the Mash-1−/− mutation, which eliminates sympathetic neurons, also prevents the development of enteric serotonergic neurons. Other enteric neuronal populations, however, including those that contain calcitonin gene related peptide are present. Enteric tyrosine hydroxylase-containing cells co-express Mash-1 and are eliminated by the Mash-1−/− mutation, consistent with the idea that in the mouse, as in the rat, these precursors generate serotonergic neurons. Serotonergic neurons are generated early in development, while calcitonin gene related peptide-containing enteric neurons are generated much later. These data suggest that enteric neurons are derived from at least two progenitor lineages. One transiently expresses sympathoadrenal markers, is Mash-1-dependent, and generates early-born enteric neurons, some of which are serotonergic. The other is Mash-1-independent, does not express sympathoadrenal markers, and generates late-born enteric neurons, some of which contain calcitonin gene related peptide