Neutron skin uncertainties of Skyrme energy density functionals

Background: Neutron-skin thickness is an excellent indicator of isovector properties of atomic nuclei. As such, it correlates strongly with observables in finite nuclei that depend on neutron-to-proton imbalance and the nuclear symmetry energy that characterizes the equation of state of neutron-rich matter. A rich worldwide experimental program involving studies with rare isotopes, parity violating electron scattering, and astronomical observations is devoted to pinning down the isovector sector of nuclear models. Purpose: We assess the theoretical systematic and statistical uncertainties of neutron-skin thickness and relate them to the equation of state of nuclear matter, and in particular to nuclear symmetry energy parameters. Methods: We use the nuclear superfluid Density Functional Theory with several Skyrme energy density functionals and density dependent pairing. To evaluate statistical errors and their budget, we employ the statistical covariance technique. Results: We find that the errors on neutron skin increase with neutron excess. Statistical errors due to uncertain coupling constants of the density functional are found to be larger than systematic errors, the latter not exceeding 0.06 fm in most neutron-rich nuclei across the nuclear landscape. The single major source of uncertainty is the poorly determined slope L of the symmetry energy that parametrizes its density dependence. Conclusions: To provide essential constraints on the symmetry energy of the nuclear energy density functional, next-generation measurements of neutron skins are required to deliver precision better than 0.06 fm.Comment: 5 pages, 4 figure

Social-Ecological Resilience and Law in the Platte River Basin

Efficiency and resistance to rapid change are hallmarks of both the judicial and legislative branches of the United States government. These defining characteristics, while bringing stability and predictability, pose challenges when it comes to managing dynamic natural systems. As our understanding of ecosystems improves, we must devise ways to account for the nonlinearities and uncertainties rife in complex social-ecological systems. This paper takes an in-depth look at the Platte River basin over time to explore how the system’s resilience—the capacity to absorb disturbance without losing defining structures and functions—responds to human driven change. Beginning with pre-European settlement, the paper explores how water laws, policies, and infrastructure influenced the region’s ecology and society. While much of the post-European development in the Platte River basin came at a high ecological cost to the system, the recent tri-state and federal collaborative Platte River Recovery and Implementation Program is a first step towards flexible and adaptive management of the social-ecological system. Using the Platte River basin as an example, we make the case that inherent flexibility and adaptability are vital for the next iteration of natural resources management policies affecting stressed basins. We argue that this can be accomplished by nesting policy in a resilience framework, which we describe and attempt to operationalize for use across systems and at different levels of jurisdiction. As our current natural resources policies fail under the weight of looming global change, unprecedented demand for natural resources, and shifting land use, the need for a new generation of adaptive, flexible natural resources governance emerges. Here we offer a prescription for just that, rooted in the social, ecological and political realities of the Platte River basin

Spin Triplet Supercurrent in Co/Ni Multilayer Josephson Junctions with Perpendicular Anisotropy

We have measured spin-triplet supercurrent in Josephson junctions of the form S/F'/F/F'/S, where S is superconducting Nb, F' is a thin Ni layer with in-plane magnetization, and F is a Ni/[Co/Ni]n multilayer with out-of-plane magnetization. The supercurrent in these junctions decays very slowly with F-layer thickness, and is much larger than in similar junctions not containing the two F' layers. Those two features are the characteristic signatures of spin-triplet supercurrent, which is maximized by the orthogonality of the magnetizations in the F and F' layers. Magnetic measurements confirm the out-of-plane anisotropy of the Co/Ni multilayers. These samples have their critical current optimized in the as-prepared state, which will be useful for future applications.Comment: 4 pages, 4 figures, formatted in RevTeX version 4. Submitted to Physical Review B on August 13th, 201

Interferometry of hyper-Rayleigh scattering by inhomogeneous thin films

The use of specific symmetry properties of the optical second-harmonic generation (the s,s-exclusion rule) has allowed us to observe high-contrast hyper-Rayleigh interference patterns in a completely diffuse light - an effect having no analog in case of linear (Rayleigh) scattering.Comment: 8 pages, 3 figure

Effect of Magnetic Impurities on Energy Exchange between Electrons

In order to probe quantitatively the effect of Kondo impurities on energy exchange between electrons in metals, we have compared measurements on two silver wires with dilute magnetic impurities (manganese) introduced in one of them. The measurement of the temperature dependence of the electron phase coherence time on the wires provides an independent determination of the impurity concentration. Quantitative agreement on the energy exchange rate is found with a theory by G\"{o}ppert et al. that accounts for Kondo scattering of electrons on spin-1/2 impurities.Comment: 4 page

Efficacy of letrozole versus clomiphene citrate for infertile women with polycystic ovary syndrome

Background: The aim was to compare ovulation induction protocols in anovulatory patients, who make up a significant percentage of infertility patients, and to determine the most appropriate treatment for patients in the clinic based on the findings.Methods: The effectiveness of clomiphene citrate (CC) and letrozole (aromatase inhibitor) in ovulation induction treatments were retrospectively compared in patients who applied for infertility in the last 5 years and were found to be anovulatory. 20 of these patients were being treated with clomiphene citrate, while the 18 were being treated with letrozole.Results: The study included a total of 38 anovulatory infertile patients. The mean age of the patients was found to be 29.3. When the endometrial thicknesses (ET) after the treatment were compared, the first group's mean EC was 6.1, while that of the second group was 9.05. The endometrial thicknesses measured after the treatments were found to be significantly different, which were consistent with other studies in the literature. Post-treatment ovulation responses were similar with 55% in both groups. In the evaluation of pregnancy outcomes, 20% of pregnancy was achieved in the first group and 33% in the second group.Conclusions: The use of letrozole, an aromatase inhibitor, may be suggested as an alternative to CC in the ovulation induction protocol in our clinical practice, particularly in obese patients

A Standard Input Format for Multiperiod Stochastic Linear Programs

Data conventions for the automatic input of multiperiod stochastic linear programs are described. The input format is based on the MPSX standard and is designed to promote the efficient conversion of originally deterministic problems by introducing stochastic variants in separate files. A flexible "header" syntax generates a useful variety of stochastic dependencies. An extension using the NETGEN format is proposed for stochastic network programs