Spectral theorem for the Lindblad equation for quadratic open fermionic systems

The spectral theorem is proven for the quantum dynamics of quadratic open systems of n fermions described by the Lindblad equation. Invariant eigenspaces of the many-body Liouvillean dynamics and their largest Jordan blocks are explicitly constructed for all eigenvalues. For eigenvalue zero we describe an algebraic procedure for constructing (possibly higher dimensional) spaces of (degenerate) non-equilibrium steady states.Comment: 19 pages, no figure

Rough Interfaces Beyond the Gaussian Approximation

We compare predictions of the Capillary Wave Model with Monte Carlo results for the energy gap and the interface energy of the 3D Ising model in the scaling region. Our study reveals that the finite size effects of these quantities are well described by the Capillary Wave Model, expanded to two-loop order (one order beyond the Gaussian approximation).Comment: Contribution to LATTICE 94. 3 pages, PostScript fil

Asymptotic Entanglement and Lindblad Dynamics: a Perturbative Approach

We consider an open bipartite quantum system with dissipative Lindblad type dynamics. In order to study the entanglement of the stationary states, we develop a perturbative approach and apply it to the physically significant case when a purely dissipative perturbation is added to the unperturbed generator which by itself would produce reversible unitary dynamics.Comment: 15 page

Asymptotic Entanglement Dynamics and Geometry of Quantum States

A given dynamics for a composite quantum system can exhibit several distinct properties for the asymptotic entanglement behavior, like entanglement sudden death, asymptotic death of entanglement, sudden birth of entanglement, etc. A classification of the possible situations was given in [M. O. Terra Cunha, {\emph{New J. Phys}} {\bf{9}}, 237 (2007)] but for some classes there were no known examples. In this work we give a better classification for the possibile relaxing dynamics at the light of the geometry of their set of asymptotic states and give explicit examples for all the classes. Although the classification is completely general, in the search of examples it is sufficient to use two qubits with dynamics given by differential equations in Lindblad form (some of them non-autonomous). We also investigate, in each case, the probabilities to find each possible behavior for random initial states.Comment: 9 pages, 2 figures; revised version accepted for publication in J. Phys. A: Math. Theo

The skill paradox: Explaining and reducing employment discrimination against skilled immigrants

Using a social identity theory approach, we theorized that recruiters might be particularly biased against skilled immigrant applicants. We refer to this phenomenon as a skill paradox, according to which immigrants are more likely to be targets of employment discrimination the more skilled they are. Furthermore, building on the common ingroup identity model, we proposed that this paradox can be resolved through human resource management (HRM) strategies that promote inclusive hiring practices (e.g., by emphasizing fit with a diverse clientele). The results from a laboratory experiment were consistent with our predictions: Local recruiters preferred skilled local applicants over skilled immigrant applicants, but only when these applicants were qualified for a specific job. This bias against qualified and skilled immigrant applicants was attenuated when fit with a diverse clientele was emphasized, but not when fit with a homogeneous clientele was emphasized or when the hiring strategy was not explained. We discuss the implications of our findings for research on employment discrimination against skilled immigrants, including the role of inclusiveness for reducing discriminatory biases

Edge-Based Compartmental Modeling for Infectious Disease Spread Part III: Disease and Population Structure

We consider the edge-based compartmental models for infectious disease spread introduced in Part I. These models allow us to consider standard SIR diseases spreading in random populations. In this paper we show how to handle deviations of the disease or population from the simplistic assumptions of Part I. We allow the population to have structure due to effects such as demographic detail or multiple types of risk behavior the disease to have more complicated natural history. We introduce these modifications in the static network context, though it is straightforward to incorporate them into dynamic networks. We also consider serosorting, which requires using the dynamic network models. The basic methods we use to derive these generalizations are widely applicable, and so it is straightforward to introduce many other generalizations not considered here

Local perceptions of development and change in Northern Ghana

ASC – Publicaties niet-programma gebonde

Differences in Heart Disease Risk Perception and Actual Cardiac Risk in Men vs. Women

Differences in Heart Disease Risk Perception and Actual Cardiac Risk in Male vs. Female Cardiac Patients Amanda Dietz, Julie Borsack, Steve Martin, Kathy L. Hill, Thomas Meade, Stephen F. Crouse, FACSM, and John S. Green, FACSM Texas A&M University, College Station, TX (Sponsor: John S. Green, FACSM) PURPOSE: To describe gender differences in both risk perception and actual coronary risk in patients with coronary artery disease (CAD). METHODS: 33 females and 67 males with documented CAD completed a questionnaire designed to assess CAD risk perception. They also underwent assessments for all ACSM risk factors. Five-point Likert scale responses to the question “Compared to others of your own age and gender, how would you rate your risk of ever having a heart attack?” were used to quantify CAD risk perception. To quantify actual risk, the number of ACSM risk markers for each subject was tabulated. It should be noted that, since all of the subjects had active CAD, they were all at high risk. Tabulations and Likert scale responses were compared using Chi-square analysis or Fisher’s Exact test with significance accepted at p\u3c0.05. To further assess risk perception accuracy, Chi-square analysis with pre-determined expected cell count percentages was used. RESULTS: Likert responses for perceived risk between genders were not significantly different but showed perception inaccuracies of the entire cohort. Only 41% of the subjects perceived their risk as “higher” or “much higher” than their peers while 27% perceived their risk as lower or much lower. 32% of the subjects perceived their risk to be the same as their peers. Comparison of risk marker number between genders was significantly different (Fisher’s exact test, p = .046) with males having 33% more markers than females. Chi-square analysis using an expected cell percentage of 75% in the “higher” Likert category, 25% in the “much higher” Likert category, and fractions of 1 in the other categories revealed significance (p\u3c.0001) with only 29.8% of subject responses in the “higher” category and 11.9% in the “much higher” category. The female cohort showed similar results with test percentages of 73% in the “higher” category and 27% in the “much higher” category. Responses were significantly different (p\u3c.0001) with only 30% choosing the “higher” category and 10% choosing the “much higher” category. CONCLUSIONS: Although significant differences in actual cardiac risk exist between genders in a cohort of cardiac patients, perceived risks are not significantly different. Both genders greatly underestimate their risk