Joint Syntacto-Discourse Parsing and the Syntacto-Discourse Treebank

Discourse parsing has long been treated as a stand-alone problem independent from constituency or dependency parsing. Most attempts at this problem are pipelined rather than end-to-end, sophisticated, and not self-contained: they assume gold-standard text segmentations (Elementary Discourse Units), and use external parsers for syntactic features. In this paper we propose the first end-to-end discourse parser that jointly parses in both syntax and discourse levels, as well as the first syntacto-discourse treebank by integrating the Penn Treebank with the RST Treebank. Built upon our recent span-based constituency parser, this joint syntacto-discourse parser requires no preprocessing whatsoever (such as segmentation or feature extraction), achieves the state-of-the-art end-to-end discourse parsing accuracy.Comment: Accepted at EMNLP 201

Altered Achilles Tendon Morphology in Individuals With Chronic Post-Stroke Hemiparesis: A Case Report

Background: Individuals post-stroke walk slowly and with more effort, which puts them at higher risks for falls. The slow walking speed results from insufficient propulsive forces generated by the paretic leg. Current rehabilitative efforts to improve walking function target increasing propulsive forces, but overlook the muscle-tendon unit. Case presentations: Two individuals with chronic post-stroke hemiparesis are presented. In both individuals post-stroke, paretic ankle plantarflexors presented with increased muscle tone. Gait kinetics revealed asymmetric propulsive forces, specifically, insufficient propulsive forces by the paretic legs, consistent with previous literature. Sonography revealed increased thickness of paretic Achilles tendon at the calcaneal insertion, in both stroke cases, in contrast to comparable Achilles tendon thickness between limbs in the non-neurologically impaired controls. Conclusion: Tendon unit integrity should be considered in individuals post-stroke who demonstrate abnormal muscle tone and insufficient propulsion during gait

Scars in Dirac fermion systems: the influence of an Aharonov--Bohm flux

Time-reversal ($\mathcal{T}$-) symmetry is fundamental to many physical processes. Typically, $\mathcal{T}$-breaking for microscopic processes requires the presence of magnetic field. However, for 2D massless Dirac billiards, $\mathcal{T}$-symmetry is broken automatically by the mass confinement, leading to chiral quantum scars. In this paper, we investigate the mechanism of $\mathcal{T}$-breaking by analyzing the local current of the scarring eigenstates and their magnetic response to an Aharonov--Bohm flux. Our results unveil the complete understanding of the subtle $\mathcal{T}$-breaking phenomena from both the semiclassical formula of chiral scars and the microscopic current and spin reflection at the boundaries, leading to a controlling scheme to change the chirality of the relativistic quantum scars. Our findings not only have significant implications on the transport behavior and spin textures of the relativistic pseudoparticles, but also add basic knowledge to relativistic quantum chaos.Comment: 37 pages, 11 figure