Diffusive energy transport in the S=1 Haldane chain compound AgVP2S6

We present the results of measurements of the thermal conductivity $\kappa$ of the spin S=1 chain compound AgVP_2S_6 in the temperature range between 2 and 300 K and with the heat flow directed either along or perpendicular to the chain direction. The analysis of the anisotropy of the heat transport allowed for the identification of a small but non-negligible magnon contribution $\kappa_m$ along the chains, superimposed on the dominant phonon contribution $\kappa_ph$. At temperatures above about 100 K the energy diffusion constant D_E(T), calculated from the $\kappa_m(T)$ data, exhibits similar features as the spin diffusion constant D_S(T), previously measured by NMR. In this regime, the behaviour of both transport parameters is consistent with a diffusion process that is caused by interactions inherent to one-dimensional S=1 spin systems.Comment: 6 pages, 4 figure

Langevin Simulation of Scalar Fields: Additive and Multiplicative Noises and Lattice Renormalization

We consider the Langevin lattice dynamics for a spontaneously broken lambda phi^4 scalar field theory where both additive and multiplicative noise terms are incorporated. The lattice renormalization for the corresponding stochastic Ginzburg-Landau-Langevin and the subtleties related to the multiplicative noise are investigated.Comment: 26 pages, 4 eps figures (Elsevier latex style

Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies

Objectives: The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the interest of improving the diagnosis and treatment of patients with atherosclerosis, including coronary artery disease. Background: Intravascular optical coherence tomography (IVOCT) is a catheter-based modality that acquires images at a resolution of ∼10 μm, enabling visualization of blood vessel wall microstructure in vivo at an unprecedented level of detail. IVOCT devices are now commercially available worldwide, there is an active user base, and the interest in using this technology is growing. Incorporation of IVOCT in research and daily clinical practice can be facilitated by the development of uniform terminology and consensus-based standards on use of the technology, interpretation of the images, and reporting of IVOCT results. Methods: The IWG-IVOCT, comprising more than 260 academic and industry members from Asia, Europe, and the United States, formed in 2008 and convened on the topic of IVOCT standardization through a series of 9 national and international meetings. Results: Knowledge and recommendations from this group on key areas within the IVOCT field were assembled to generate this consensus document, authored by the Writing Committee, composed of academicians who have participated in meetings and/or writing of the text. Conclusions: This document may be broadly used as a standard reference regarding the current state of the IVOCT imaging modality, intended for researchers and clinicians who use IVOCT and analyze IVOCT data

Prevalence of and risk factors for age-related macular degeneration in a multiethnic Asian cohort

10.1001/archophthalmol.2011.376Archives of Ophthalmology1304480-486AROP

Impact of Diabetic Retinopathy on Vision-Specific Function

10.1016/j.ophtha.2009.09.035Ophthalmology1174757-765OPHT

Retinal vascular caliber and diabetes in a multiethnic asian population

10.1080/10739680902975222Microcirculation166534-543MROC