Dimensional relationships between the sphenoid sinus, maxillary sinuses and other craniomaxillofacial structures using cone-beam computed tomography analysis.

Introduction: The study investigated dimensional relationships between the sphenoid and maxillary sinuses and other selected craniomaxillofacial structures by using traditional cephalometric and volumetric procedures based on cone beam computed tomographic (CBCT) data. Methods and Materials: A retrospective three-dimensional (volumetric) and two-dimensional (conventional cephalometric) analyses were conducted on CBCT datasets of 27 subjects who met the inclusional criteria from a sampled database of 2,290 individuals. Subjects were divided into 3 groups: (1) pre- fused spheno-occipital synchondrosis \u3c 18 years (n=8), (2) fused spheno-occipital synchondrosis \u3c 18 years (n=9), and (3) = 18 years with fused spheno-occipital synchondosis (n= 10). Results: Differences between studied groups were found for linear and angular measurement. Specific correlations were found between certain topographic and internal measurements, and some sinus dimensions and other selected craniomaxillofacial structures. Conclusion: Dimensional correlations exist between the sphenoid and maxillary sinuses and development of other selected craniomaxillofacial structures

Long-Term Profile Variability of Double-Peaked Emmission Lines in AGNs

An increasing number of AGNs exhibit broad, double-peaked Balmer emission lines, which arise from the outer regions of the accretion disk which fuels the AGN. The line profiles vary on timescales of 5--10 years. Our group has monitored a set of 20 double-peaked emitters for the past 8 years (longer for some objects). Here we describe a project to characterize the variability patterns of the double-peaked H alpha line profiles and compare with those of two simple models: a circular disk with a spiral arm and an elliptical disk.Comment: 2 pages, 1 figure, to appear in the proceedings of "The Interplay among Black Holes, Stars and ISM in Galactic Nuclei", IAU 222, eds. T. Storchi Bergmann, L.C. Ho, and H.R. Schmit

Hidden symmetries in two dimensional field theory

The bosonization process elegantly shows the equivalence of massless scalar and fermion fields in two space-time dimensions. However, with multiple fermions the technique often obscures global symmetries. Witten's non-Abelian bosonization makes these symmetries explicit, but at the expense of a somewhat complicated bosonic action. Frenkel and Kac have presented an intricate mathematical formalism relating the various approaches. Here I reduce these arguments to the simplest case of a single massless scalar field. In particular, using only elementary quantum field theory concepts, I expose a hidden $SU(2)\times SU(2)$ chiral symmetry in this trivial theory. I then discuss in what sense this field should be interpreted as a Goldstone boson.Comment: 15 pages. Revision adds numerous references and puts things in better historical contex

Memory Biases in Left Versus Right Implied Motion

People remember moving objects as having moved farther along in their path of motion than is actually the case; this is known as representational momentum (RM). Some authors have argued that RM is an internalization of environmental properties such as physical momentum and gravity. Five experiments demonstrated that a similar memory bias could not have been learned from the environment. For right-handed Ss, objects apparently moving to the right engendered a larger memory bias in the direction of motion than did those moving to the left. This effect, clearly not derived from real-world lateral asymmetries, was relatively insensitive to changes in apparent velocity and the type of object used, and it may be confined to objects in the left half of visual space. The left–right effect may be an intrinsic property of the visual operating system, which may in turn have affected certain cultural conventions of left and right in art and other domains. (PsycINFO Database Record (c) 2016 APA, all rights reserved