Socio-spatial analysis of four university campuses: the implications of spatial configuration on creation and transmission of knowledge

An exploratory study of space use, interaction and students? and academics? subjectiveperceptions of interaction and vitality in the four campus sites of the PontificiaUniversidad Católica de Chile (PUC), in Santiago de Chile is presented. The fourcampuses, which differ substantially in their architecture, size and the programmaticnature of the disciplines they house, were modelled as spatial configurations usingspace syntax methods. Observations of patterns of space use and movement werecarried out and a questionnaire survey of staff and students was used to elicit perceptualand reported communication network strengths for both academic staff andstudents. One might expect that, given the twin roles of a university institution in thegeneration of new knowledge and induction of alumni into a ?professional? socialsolidarity, the roles of global and local integration would tend to compete. Globalsegregation in combination with local integration can construct the conditions forstudents to appropriate the open space and generate a powerful local identity at thelevel of the academic unit. However, global integration appears to play an importantrole in making those local solidarities accessible to one another and therefore in thegeneration of new knowledge and solidarities. The data at hand, though exploratoryin nature, suggest that the dynamic is more complex: local identity of the disciplineappears to be a necessary component in the construction of interdisciplinary ?weak?networks at the scale of the institution as a whole

Near threshold rotational excitation of molecular ions by electron-impact

New cross sections for the rotational excitation of H$_3^+$ by electrons are calculated {\it ab initio} at low impact energies. The validity of the adiabatic-nuclei-rotation (ANR) approximation, combined with $R$-matrix wavefunctions, is assessed by comparison with rovibrational quantum defect theory calculations based on the treatment of Kokoouline and Greene ({\it Phys. Rev. A} {\bf 68} 012703 2003). Pure ANR excitation cross sections are shown to be accurate down to threshold, except in the presence of large oscillating Rydberg resonances. These resonances occur for transitions with $\Delta J=1$ and are caused by closed channel effects. A simple analytic formula is derived for averaging the rotational probabilities over such resonances in a 3-channel problem. In accord with the Wigner law for an attractive Coulomb field, rotational excitation cross sections are shown to be large and finite at threshold, with a significant but moderate contribution from closed channels.Comment: 3 figures, a5 page

Social Determinants of Health Associated with HBV Testing and Access to Care among Foreign-born Persons Residing in the United States: 2009 - 2012

Objectives: To describe how select Social Determinants of Health (SDH) are associated with the burden of hepatitis B virus (HBV) infection among foreign-born persons residing in the United States. Methods: Multivariate logistic regression was used to examine the Racial and Ethnic Approaches to Community Health (REACH) 2010 Risk Factor Survey data to investigate the independent relationship between SDH and HBV testing and access to care. Results: HBV infected persons with insurance were more likely to see a physician than those without. Respondents worried about money to pay rent or mortgage were more likely to report HBV infection than individuals who reported they never worry. Compared to English speakers, Spanish-speakers were less likely to report HBV infection, Vietnamese-speakers were more likely to see a physician for HBV infection, and Khmer-speakers were less likely to be tested. Conclusions: Health insurance coverage, worries about paying rent, and language of interview all differentially affect HBV testing and linkages to care among foreign–born persons. Multi-sectorial stakeholder collaborative efforts should integrate resources to provide culturally sensitive health promotion campaigns which may improve HBV related outcomes

Nonclassical paths in the recurrence spectrum of diamagnetic atoms

Using time-independent scattering matrices, we study how the effects of nonclassical paths on the recurrence spectra of diamagnetic atoms can be extracted from purely quantal calculations. This study reveals an intimate relationship between two types of nonclassical paths: exotic ghost orbits and diffractive orbits. This relationship proves to be a previously unrecognized reason for the success of semiclassical theories, like closed-orbit theory, and permits a comprehensive reformulation of the semiclassical theory that elucidates its convergence properties.Comment: 5 pages, 4 figure

A General Precipitation-Limited L_X-T-R Relation Among Early-Type Galaxies

The relation between X-ray luminosity (L_X) and ambient gas temperature (T) among massive galactic systems is an important cornerstone of both observational cosmology and galaxy-evolution modeling. In the most massive galaxy clusters, the relation is determined primarily by cosmological structure formation. In less massive systems, it primarily reflects the feedback response to radiative cooling of circumgalactic gas. Here we present a simple but powerful model for the L_X-T relation as a function of physical aperture R within which those measurements are made. The model is based on the precipitation framework for AGN feedback and assumes that the circumgalactic medium is precipitation-regulated at small radii and limited by cosmological structure formation at large radii. We compare this model with many different data sets and show that it successfully reproduces the slope and upper envelope of the L_X-T-R relation over the temperature range from ~0.2 keV through >10 keV. Our findings strongly suggest that the feedback mechanisms responsible for regulating star formation in individual massive galaxies have much in common with the precipitation-triggered feedback that appears to regulate galaxy-cluster cores.Comment: Submitted to ApJ, 9 pages, 3 figures (v2 fixes a few small typos

Normal State Nernst Effect in Electron-doped Pr2-xCexCuO4: Superconducting Fluctuations and Two-band Transport

We report a systematic study of normal state Nernst effect in the electron-doped cuprates Pr$_{2-x}$Ce$_x$CuO$_{4-\delta}$ over a wide range of doping (0.05$\leq x \leq$0.21) and temperature. At low temperatures, we observed a notable vortex Nernst signal above T$_c$ in the underdoped films, but no such normal state vortex Nernst signal is found in the overdoped region. The superconducting fluctuations in the underdoped region are most likely incoherent phase fluctuations as found in hole-doped cuprates. At high temperatures, a large normal state Nernst signal is found at dopings from slightly underdoped to highly overdoped. Combined with normal state thermoelectric power, Hall effect and magnetoresistance measurements, the large Nernst effect is compatible with two-band model. For the highly overdoped films, the large Nernst effect is anomalous and not explainable with a simple hole-like Fermi surface seen in photoemission experiments.Comment: 9 pages, 8 figures, accepted in PR