DOES ECONOMIC VULNERABILITY DEPEND ON PLACE OF RESIDENCE? ASSET POVERTY ACROSS THE RURAL-URBAN CONTINUUM

This paper uses Panel Study of Income Dynamics data for 1989, 1994, and 1999 to examine why some U.S. households are asset poor; that is, why households have insufficient resources to invest in their future or to sustain household members at a basic level during times of economic disruption. The study contributes to an improved understanding of asset poverty's correlates by examining the influence of place of residence; the extant literature has focused on individual-level explanations. We estimate a random-effects logistic model of the probability that an individual is asset poor at a given point in time as a function of household-level (e.g. age, gender, race of the household head and family structure) and place-level (regional and rural-urban continuum) variables. The central finding of the paper is that place of residence is an important determinant of asset poverty, above and beyond the influence of household characteristics. We find that living in a central metropolitan county and in a nonmetropolitan area is associated with a higher risk of being asset poor, all else being equal. Implications for future research are discussed.Food Security and Poverty,

Inelastic neutron scattering signal from deconfined spinons in a fractionalized antiferromagnet

We calculate the contribution of deconfined spinons to inelastic neutron scattering (INS) in the fractionalized antiferromagnet (AF*), introduced elsewhere. We find that the presence of free spin-1/2 charge-less excitations leads to a continuum INS signal above the Neel gap. This signal is found above and in addition to the usual spin-1 magnon signal, which to lowest order is the same as in the more conventional confined antiferromagnet. We calculate the relative weights of these two signals and find that the spinons contribute to the longitudinal response, where the magnon signal is absent to lowest order. Possible higher-order effects of interactions between magnons and spinons in the AF* phase are also discussed.Comment: 9 page

STM Studies of TbTe3: Evidence for a fully Incommensurate Charge Density Wave

We observe unidirectional charge density wave ordering on the cleaved surface of TbTe3 with a Scanning Tunneling Microscope at ~6 K. The modulation wave-vector q_{CDW} as determined by Fourier analysis is 0.71 +/- 0.02 * 2 pi/c. (Where c is one edge of the in-plane 3D unit cell.) Images at different tip-sample voltages show the unit cell doubling effects of dimerization and the layer below. Our results agree with bulk X-ray measurements, with the addition of ~(1/3) * 2 pi/a ordering perpendicular to the CDW. Our analysis indicates that the CDW is incommensurate.Comment: 4 pages, 4 figure

Vortices and quasiparticles near the "superconductor-insulator" transition in thin films

We study the low temperature behavior of an amorphous superconducting film driven normal by a perpendicular magnetic field (B). For this purpose we introduce a new two-fluid formulation consisting of fermionized field induced vortices and electrically neutralized Bogoliubov quasiparticles (spinons) interacting via a long-ranged statistical interaction. This approach allows us to access a novel non-Fermi liquid phase which naturally interpolates between the low B superconductor and the high B normal metal. We discuss the transport, thermodynamic, and tunneling properties of the resulting "vortex metal" phase.Comment: 4 pages, 1 figure, references adde

Quantum Resistive Transition in Type II Superconductors under Magnetic Field

It is shown that, within a Ginzburg-Landau (GL) formalism, the superconducting fluctuation is insulating at zero temperature even if the fluctuation dynamics is metallic (dissipative). Based on this fact, the low temperature behavior of the $H_{c2}$-line and the resistivity curves near a zero temperature transition are discussed. In particular, it is pointed out that the neglect of quantum fluctuations in data analysis of the dc resistivity may lead to an under-estimation of the $H_{c2}$ values near zero temperature.Comment: 7 page

Vortex Fluctuations in the Critical Casimir Effect of Superfluid and Superconducting Films

Vortex-loop renormalization techniques are used to calculate the magnitude of the critical Casimir forces in superfluid films. The force is found to become appreciable when size of the thermal vortex loops is comparable to the film thickness, and the results for T < Tc are found to match very well with perturbative renormalization theories that have only been carried out for T > Tc. When applied to a high-Tc superconducting film connected to a bulk sample, the Casimir force causes a voltage difference to appear between the film and bulk, and estimates show that this may be readily measurable.Comment: 4 pages, 5 figures, Revtex 4, typo correctio

Phase diagrams, critical and multicritical behavior of hard-core Bose-Hubbard models

We determine the zero-temperature phase diagram of the hard-core Bose-Hubbard model on a square lattice by mean-field theory supplemented by a linear spin-wave analysis. Due to the interplay between nearest and next-nearest neighbor interaction and cubic anisotropy several supersolid phases with checkerboard, stripe domain or intermediate symmetry are stabilized. The phase diagrams show three different topologies depending on the relative strength of nearest and next-nearest neighbor interaction. We also find a rich variety of new quantum critical behavior and multicritical points and discuss the corresponding effective actions and universality classes.Comment: 19 pages, ReVTeX, 18 figures included, submitted to PR

Concurrent Validity of the Face Valid Food Security Measure

Our objective was to assess the concurrent validity of the face valid food security categorical algorithm with Hawaii residents. We also hypothesized that there would be differences in food security status between ethnic groups. We used the 18 question indicators of the Core Food Security Module (CFSM) to develop the face valid food security measure. The “face valid” measure was created previously by this research team as a more valid food security measure in Hawaii. Findings compared the face valid categorical measure and the CFSM scale measure with various demographic, economic, dietary variables, and use of assistance programs. The sample included 1,603 Hawaii residents drawn from a statewide telephone survey and a survey of charitable food recipients. Statistical analysis included ANOVA, chi-square, and regression analysis of food security measures with related variables. In general, progressively deteriorating food security status resulted in concurrent decreases in vegetable intake, increased reliance on a cheap, high-fat, high-sodium noodle product, and increased reliance on resource augmentation behaviors. Factors such as a greater number of children, limited savings, and recent loss of a job were found to compromise food security status. WIC benefits, frequent use of a food pantry, and the presence of a senior adult in the household appeared protective. In this sample Asians, except for Filipinos, were more food secure; Hawaiians and Part-Hawaiians, and Samoans, were more likely to experience hunger. Findings were consistent with previous work and suggest that the face valid food security measure does exhibit concurrent validity.