Magnification relations in gravitational lensing via multidimensional residue integrals

We investigate the so-called magnification relations of gravitational lensing models. We show that multidimensional residue integrals provide a simple explanation for the existence of these relations, and an effective method of computation. We illustrate the method with several examples, thereby deriving new magnification relations for galaxy lens models and microlensing (point mass lensing).Comment: 16 pages, uses revtex4, submitted to Journal of Mathematical Physic

Uncle Josh\u27s Huskin\u27 Dance

https://digitalcommons.library.umaine.edu/mmb-ps/2932/thumbnail.jp

Critical role of interlayer dimer correlations in the superconductivity of La3_3Ni2_2O7_7

The recent discovery of superconductivity in La$_3$Ni$_2$O$_7$ with $T_\mathrm{c} \simeq 80~\mathrm{K}$ under high pressure opens up a new route to high-$T_\mathrm{c}$ superconductivity. This material realizes a bilayer square lattice model featuring a strong interlayer hybridization unlike many unconventional superconductors. A key question in this regard concerns how electronic correlations driven by the interlayer hybridization affect the low-energy electronic structure and the concomitant superconductivity. Here, we demonstrate using a cluster dynamical mean-field theory that the interlayer electronic correlations (IECs) induce a Lifshitz transition resulting in a change of Fermi surface topology. By solving an appropriate gap equation, we further show that the dominant pairing instability (intraorbital $s$-wave/interorbital $d_{x^2-y^2}$-wave) is enhanced by the IECs. The underlying mechanism is the quenching of a strong ferromagnetic channel, resulting from the Lifshitz transition driven by the IECs. Our finding establishes the role of IECs in La$_3$Ni$_2$O$_7$ and potentially paves the way to designing higher-\Tc nickelates

Does gravitational wave propagate in the five dimensional space-time with Kaluza-Klein monopole?

The behavior of small perturbations around the Kaluza-Klein monopole in the five dimensional space-time is investigated. The fact that the odd parity gravitational wave does not propagate in the five dimensional space-time with Kaluza-Klein monopole is found provided that the gravitational wave is constant in the fifth direction.Comment: 10 @ages, LATE

Favorable Ratings of Providers\u27 Communication Behaviors Among U.S. Women with Depression: A Population-based Study Applying the Behavioral Model of Health Services Use

Background Little is known about the relationships between sociodemographic characteristics and ratings of provider communication behavior among women with depression in the United States. This study uses the Andersen Behavioral Model to examine the relationships among predisposing, enabling, and need factors and ratings of perceived patient–provider communication in women with depression. Methods The sample consisted of women with depression who visited any provider in the previous 12 months in the 2002–2008 Medical Expenditure Panel Survey (n = 3,179; weighted n = 4,707,255). Multivariate logistic regression was used to examine the independent contribution of predisposing, enabling, and need factors on providers\u27 communication behavior measures. Findings Black (non-Hispanic) women were more likely to report that providers always listened carefully (odds ratio [OR], 1.40; 95% confidence interval [CI], 1.01–1.94), explained so they understood (OR, 1.53; 95% CI, 1.10–2.11), and showed respect for what they had to say (OR, 1.39; 95% CI, 1.01–1.92). Women participating in the paid workforce and those without a usual source of care were at increased risk for less favorable experiences. Conclusions Participation in the paid workforce and lack of a usual source of care were associated with an increased likelihood of less optimal communication experiences. Implications for Practice and/or Policy Ensuring that women with depression have reliable access to a continuous source of care and expanding the availability of nonemergent, after-hours care may be instrumental for improving patient–provider communication in this population

The Impact of Patient–Provider Communication and Language Spoken on Adequacy of Depression Treatment for U.S. Women

Many women with depression are untreated or undertreated for their condition. The quality of patient–provider communication may impact the receipt of depression treatment. We examine the relationship between patient–provider communication and receipt of adequate treatment for depression among women. The study sample consisted of women with depression who visited a provider in the previous 12 months in the 2002–2008 Medical Expenditure Panel Survey (N = 3,179). Multivariate regression was used to examine the independent contribution of sociodemographic characteristics, health care factors, patient–provider communication, and respondent language on depression treatment status (none, some, adequate). We found that more than one-third of women with depression in the United States did not receive adequate treatment. Women reporting that providers usually or always listened carefully were more likely to receive adequate treatment (OR = 1.59; 95% CI = 1.10−2.30 and OR = 1.55; 95% CI = 1.07−2.23, respectively). Non-English-speaking women were 50% less likely to receive adequate treatment (OR = 0.49; 95% CI = 0.30−0.80). Having a usual source of care was associated with an increased likelihood of receiving some and adequate treatment (OR = 1.84; 95% CI = 1.24−2.73 and OR = 2.22; 95% CI = 1.61−3.05, respectively). Effective provider listening behaviors may help increase the number of U.S. women with depression who receive adequate treatment. Efforts to improve language access for limited English-proficient women are likely critical for improving treatment outcomes in this population. Additionally, ensuring that women with depression have consistent access to health care services is important for obtaining adequate depression care

Gravitational Microlensing Near Caustics I: Folds

We study the local behavior of gravitational lensing near fold catastrophes. Using a generic form for the lensing map near a fold, we determine the observable properties of the lensed images, focusing on the case when the individual images are unresolved, i.e., microlensing. Allowing for images not associated with the fold, we derive analytic expressions for the photometric and astrometric behavior near a generic fold caustic. We show how this form reduces to the more familiar linear caustic, which lenses a nearby source into two images which have equal magnification, opposite parity, and are equidistant from the critical curve. In this case, the simplicity and high degree of symmetry allows for the derivation of semi-analytic expressions for the photometric and astrometric deviations in the presence of finite sources with arbitrary surface brightness profiles. We use our results to derive some basic properties of astrometric microlensing near folds, in particular we predict for finite sources with uniform and limb darkening profiles, the detailed shape of the astrometric curve as the source crosses a fold. We find that the astrometric effects of limb darkening will be difficult to detect with the currently planned accuracy of the Space Interferometry Mission. We verify our results by numerically calculating the expected astrometric shift for the photometrically well-covered Galactic binary lensing event OGLE-1999-BUL-23, finding excellent agreement with our analytic expressions. Our results can be applied to any lensing system with fold caustics, including Galactic binary lenses and quasar microlensing.Comment: 37 pages, 7 figures. Revised version includes an expanded discussion of applications. Accepted to ApJ, to appear in the August 1, 2002 issue (v574