Anomalies and entanglement renormalization

We study 't Hooft anomalies of discrete groups in the framework of (1+1)-dimensional multiscale entanglement renormalization ansatz states on the lattice. Using matrix product operators, general topological restrictions on conformal data are derived. An ansatz class allowing for optimization of MERA with an anomalous symmetry is introduced. We utilize this class to numerically study a family of Hamiltonians with a symmetric critical line. Conformal data is obtained for all irreducible projective representations of each anomalous symmetry twist, corresponding to definite topological sectors. It is numerically demonstrated that this line is a protected gapless phase. Finally, we implement a duality transformation between a pair of critical lines using our subclass of MERA.Comment: 12+18 pages, 6+5 figures, 0+2 tables, v2 published versio

Mechanical, Electrical, and Magnetic Properties of Ni Nanocontacts

The dynamic deformation upon stretching of Ni nanowires as those formed with mechanically controllable break junctions or with a scanning tunneling microscope is studied both experimentally and theoretically. Molecular dynamics simulations of the breaking process are performed. In addition, and in order to compare with experiments, we also compute the transport properties in the last stages before failure using the first-principles implementation of Landauer's formalism included in our transport package ALACANT.Comment: 5 pages, 6 figure

Transport in magnetically ordered Pt nanocontacts

Pt nanocontacts, like those formed in mechanically controlled break junctions, are shown to develop spontaneous local magnetic order. Our density functional calculations predict that a robust local magnetic order exists in the atoms presenting low coordination, i. e., those forming the atom-sized neck. In contrast to previous work, we thus find that the electronic transport can be spin-polarized, although the net value of the conductance still agrees with available experimental information. Experimental implications of the formation of this new type of nanomagnet are discussed.Comment: 4 pages, 3 figure

The Interaction of Obesity Related Genotypes, Phenotypes, and Economics: An Experimental Economics Approach with Mice

Food intake is greatly influenced by economic factors. Consequently, neuroeconomics has been identified as a new and important area for understanding the interaction between genotypes and phenotypes related to food intake. A foundational element of economics is choice between alternatives. Changing food choices are a central element in the explanation of the increasing obesity rates in human populations. The purpose of this research is to incorporate the key element of choice into the investigation of food intake and weight-related phenotypes for mice in an operant chamber setting. Using normal mice, and mice with a mutation in the Tubby gene (Tub-Mut) which results in adult onset obesity, this research will investigate different behavioral responses among genotypes, as well as unexplored phenotype outcomes when mice are confronted with a falling price of a high fat food relative to a low fat food. Results for both genotypes indicate that as the price of the high fat food falls, consumption of that food increases, but consumption of the low fat food does not decrease in a compensatory fashion. For both genotypes, weight and body fat percentage increases with decreasing high fat food price, but ghrelin and leptin levels do not significantly change. The Tub-Mut shows a significant increase in the area under the glucose tolerance curve, suggestive of a diabetic state. These results show that accounting for choice in neuroeconomic studies is important to understanding the complex regulation of body weight and diabetes.Food Consumption/Nutrition/Food Safety,

The study of parameter optimization in vehicle-borne tracking systems Final technical report

Data smoothing technique for parameter optimization in free flight orbit vehicle-borne tracking system

Reading First Impact Study: Interim Report

This report, written by Abt Associates and MDRC and published by the U.S. Department of Education's Institute of Education Sciences, finds that Reading First increased the amount of time that teachers spent on the five essential components of reading instruction, as defined by the National Reading Panel. While Reading First did not improve students' reading comprehension on average, there are some indications that some sites had impacts on both instruction and reading comprehension. An overview puts these interim findings in context