From bound states to resonances: analytic continuation of the wave function

Single-particle resonance parameters and wave functions in spherical and deformed nuclei are determined through analytic continuation in the potential strength. In this method, the analyticity of the eigenvalues and eigenfunctions of the Schroedinger equation with respect to the coupling strength is exploited to analytically continue the bound-state solutions into the positive-energy region by means of Pade' approximants of the second kind. The method is here applied to single-particle wave functions of the $^{154}Sm$ and $^{131}Eu$ nuclei. A comparison of the results with the direct solution of the Schroedinger equation shows that the method can be confidently applied also in coupled-channel situations requiring high numerical accuracy.Comment: 13 pages, 3 figure

Dielectric and polarization experiments in high loss dielectrics: a word of caution

The recent quest for improved functional materials like high permittivity dielectrics and/or multiferroics has triggered an intense wave of research. Many materials have been checked for their dielectric permittivity or their polarization state. In this report, we call for caution when samples are simultaneously displaying insulating behavior and defect-related conductivity. Many oxides containing mixed valent cations or oxygen vacancies fall in this category. In such cases, most of standard experiments may result in effective high dielectric permittivity which cannot be related to ferroelectric polarization. Here we list few examples of possible discrepancies between measured parameters and their expected microscopic origin

Polaron relaxation in ferroelectric thin films

We report a dielectric relaxation in ferroelectric thin films of the ABO3 family. We have compared films of different compositions with several growth modes: sputtering (with and without magnetron) and sol-gel. The relaxation was observed at cryogenic temperature (T<100K) for frequencies from 100Hz up to 10MHz. This relaxation activation energy is always lower than 200meV. It is very similar to the polaron relaxation that we reported in the parent bulk perovskites. Being independent of the materials size, morphology and texture, this relaxation can be a useful probe of defects in actual integrated capacitors with no need for specific shapin

Interface-driven magnetocapacitance in a broad range of materials

Triggered by the revival of multiferroic materials, a lot of effort is presently undergoing as to find a coupling between a capacitance and a magnetic field. We show in this report that interfaces are the right way of increasing such a coupling provided free charges are localized on these two-dimensional defects. Starting from commercial diodes at room temperature and going to grain boundaries in giant permittivity materials and to ferroelectric domain walls, a clear magnetocapacitance is reported which is all the time more than a few percent for a magnetic field of 90kOe. The only tuning parameter for such strong coupling to arise is the dielectric relaxation time which is reached on tuning the operating frequency and the temperature in many different materials

Proton emission, gamma deformation, and the spin of the isomeric state of 141Ho

Abstract The nonadiabatic quasiparticle model for triaxial shapes is used to perform calculations for decay of 141 Ho, the only known odd-Z even-N deformed nucleus for which fine structure in proton emission from both ground and isomeric states was observed. All experimental data corresponding to this unique case namely, the rotational spectra of parent and daughter nuclei, decay widths and branching ratios for ground and isomeric states, could be well explained with a strong triaxial deformation γ ∼ 20 ° . The recent experimental observation of fine structure decay from the isomeric state, can be explained only with an assignment of I = 3 / 2 + as the decaying state, in contradiction with the previous assignment, of I = 1 / 2 + , based on adiabatic calculations. This study reveals that proton emission measurements could be a precise tool to probe triaxial deformations and other structural properties of exotic nuclei beyond the proton drip-line

Evidence for partial rotation alignment in proton emitting 121Pr

Abstract Using nonadiabatic quasiparticle calculations we reproduce the experimental half-life for proton radioactivity in 121Pr assuming that the decaying state has angular momentum J π = 7 / 2 − , thus showing for the first time clear evidence for partial rotation alignment in a proton emitting nucleus. The treatment of the pairing interaction in the BCS approach produces profound changes in the ordering of energy levels, and at high deformation, the state 7 / 2 − coming from the h 11 / 2 spherical shell becomes the bandhead

Correlates of Low-Fat Milk Consumption in a Multi-Ethnic Population

Objective: To assess the correlates of low-fat milk consumption in a multi-ethnic population. Design: Cross-sectional random digit dial telephone survey of adults residing in Hawaii. Setting &amp; Participants: The survey was completed by 600 adults who consumed cow’s milk. Five ethnicities composed over 86% of the sample: Caucasian (36%), Hawaiian (17%), Japanese (18%), Filipino (10%), and Chinese (5%). The average age of participant was 45.6. 84% had completed high school and 35% had completed college. Variables Measured: All variables were self-reported. Type of milk consumed (high-fat vs. low-fat) was the dependent variable. Independent variables included age, gender, ethnicity, body mass, attitude, normative beliefs, and stage of change. Analysis: Chi-squares and logistic regression were used for the analysis (p &lt; .05). Results: Younger and less educated people were less likely to drink low-fat milk, as were Native Hawaiians and Filipinos. In the multivariate analyses only attitudes, normative beliefs, and education were significant predictors. Conclusions and Implications: Attitudes and normative beliefs towards milk consumption explain more of the variance in type of milk consumption than demographic characteristics. This data indicates the feasibility of testing interventions designed to influence attitudes and normative beliefs towards low-fat milk consumption in Asian and Pacific Island communities

Revised structural phase diagram of (Ba0.7Ca0.3TiO3)-(BaZr0.2Ti0.8O3)

The temperature-composition phase diagram of barium calcium titanate zirconate (x(Ba0.7Ca0.3TiO3)(1-x)(BaZr0.2Ti0.8O3); BCTZ) has been reinvestigated using high-resolution synchrotron x-ray powder diffraction. Contrary to previous reports of an unusual rhombohedral-tetragonal phase transition in this system, we have observed an intermediate orthorhombic phase, isostructural to that present in the parent phase, BaTiO3, and we identify the previously assigned T-R transition as a T-O transition. We also observe the O-R transition coalescing with the previously observed triple point, forming a phase convergence region. The implication of the orthorhombic phase in reconciling the exceptional piezoelectric properties with the surrounding phase diagram is discussed

CROWN-TO-ROOT RATIO IN ENDODONTIC SURGERY: A SURVIVAL STUDY

Aim: to assess the influence of the crown height (CH), root length (RL) and crown-to-root ratio (CRR) on the survival of te- eth subjected to surgical endodontic retreatment and classi- fied as periapically healed. Methods: a single operator performed all the endodontic mi- crosurgery interventions. The present analysis selected the te- eth classified as ‘‘complete periapical healing’’ according to the Molven-Halse-Grung scale. The periapical radiographs were analyzed by two independent calibrated examiners, who measured CH and RL in a blind manner. The CRR was calcula- ted as the ratio of the two variables CH and RL. The measure- ments were performed by comparing the post-operative radio- graphs (t0) with those taken for a previous retrospective analysis (t1) and the most recent available (t2). An independent statistician conducted a survival analysis using Kaplan-Meier plots and a log-rank test (a = 0.05). Results: thirty-eight patients were evaluated, each one contri- buting to the study with a single tooth. The mean follow-up pe- riod was 5,96 ± 3,36 years. Comparing the CRR and RL values between t1 and t2, the difference was found statistically signifi- cant (p = 0.03). Survival was improved for the teeth with roots longer than 7 mm. There were no statistically significant diffe- rences among the remaining comparisons. Conclusions: root length ≥ 7mm exhibited better chances of long-term survival. Over time, a risk of further decrease of cli- nical RL due to periodontal disease and consequent increase of CRR could be critical by a mechanical point of view. Other studies are needed

Role of dynamical particle-vibration coupling in reconciliation of the d3/2d_{3/2} puzzle for spherical proton emitters

It has been observed that decay rate for proton emission from $d_{3/2}$ single particle state is systematically quenched compared with the prediction of a one dimensional potential model although the same model successfully accounts for measured decay rates from $s_{1/2}$ and $h_{11/2}$ states. We reconcile this discrepancy by solving coupled-channels equations, taking into account couplings between the proton motion and vibrational excitations of a daughter nucleus. We apply the formalism to proton emitting nuclei $^{160,161}$Re to show that there is a certain range of parameter set of the excitation energy and the dynamical deformation parameter for the quadrupole phonon excitation which reproduces simultaneously the experimental decay rates from the 2$d_{3/2}$, 3$s_{1/2}$ and 1$h_{11/2}$ states in these nuclei.Comment: RevTex, 12 pages, 4 eps figure