Zener transitions between dissipative Bloch bands. II: Current Response at Finite Temperature

We extend, to include the effects of finite temperature, our earlier study of the interband dynamics of electrons with Markoffian dephasing under the influence of uniform static electric fields. We use a simple two-band tight-binding model and study the electric current response as a function of field strength and the model parameters. In addition to the Esaki-Tsu peak, near where the Bloch frequency equals the damping rate, we find current peaks near the Zener resonances, at equally spaced values of the inverse electric field. These become more prominenent and numerous with increasing bandwidth (in units of the temperature, with other parameters fixed). As expected, they broaden with increasing damping (dephasing).Comment: 5 pages, LateX, plus 5 postscript figure

Disorder-specific patterns of emotion coregulation in couples: Comparing obsessive compulsive disorder and anorexia nervosa

Impaired emotion regulation and maladaptive strategies to manage distress are central to psychopathology, including obsessive-compulsive disorder (OCD) and anorexia nervosa (AN). Emotion regulation can be fostered or thwarted by romantic partners, and the tendency to rely on interpersonally oriented emotion regulation may vary by disorder. This study examined coregulation as a form of interpersonal emotion regulation in OCD and AN. We hypothesized that OCD is associated with exaggerated and AN with diminished coregulation, and that OCD patients have greater overall levels of emotional arousal than AN patients. Greater symptom severity was expected to exacerbate these opposing tendencies. Vocally encoded emotional arousal was measured during couple conversations in 34 AN patients, 18 OCD patients, and their partners. Two indicators of coregulation (covariation and coupling) were analyzed using cross-lagged actor-partner interdependence and coupled linear oscillator models. As hypothesized, OCD was associated with greater overall emotional arousal than AN. Symptom severity was not associated with emotional arousal or coregulation. Covariation differed in the opposite direction of the hypothesis; there was no difference in coupling. AN patients exhibited consistent coregulation, indicating high reactivity to partners' emotional arousal which may contribute to interpersonal avoidance. OCD couples showed limited predictability of patients' arousal over time, while partners were affected by the patients' emotional arousal; thus, symptom accommodation may in part be partners' attempts at managing their own distress along with the patients'. A better understanding of interpersonal emotion regulation in OCD and AN can inform treatment by targeting interaction patterns that may maintain symptoms

Findings from a couple-based open trial for adult anorexia nervosa

Adult anorexia nervosa (AN) often is persistent, significantly erodes quality of life for both the patient and loved ones, and carries high medical and psychiatric comorbidity. Whereas individual psychotherapy for adult AN leads to improvement in some patients, recent findings indicate that the magnitude of improvement is limited: Only a small percentage of individuals fully recover and dropout rates are high. Thus, it is important to build upon current interventions to improve treatment response. We present results from an open trial of a couple-based intervention for adult anorexia nervosa as an adjunct treatment to standard multidisciplinary care. Twenty couples received treatment over approximately 26 weeks, including a couple-based intervention, individual CBT sessions, psychiatry visits for medication management, and nutritional counseling sessions. The results indicate that patients improved at posttest and 3-month follow-up on a variety of AN-related measures, anxiety and depression, and relationship adjustment. Partners also improved on anxiety, depression, and relationship adjustment. In an exploratory analysis, the multicomponent couple treatment intervention was benchmarked to well-conducted randomized controlled trials of individual therapy for AN; the couple intervention seems to compare favorably on AN-related measures and was associated with a lower dropout rate. In spite of methodological limitations, the findings suggest that including partners in the treatment of adult AN holds potential for bolstering treatment outcomes

The one dimensional Hydrogen atom revisited

The one dimensional Schroedinger hydrogen atom is an interesting mathematical and physical problem to study bound states, eigenfunctions and quantum degeneracy issues. This 1D physical system gave rise to some intriguing controversy over more than four decades. Presently, still no definite consensus seems to have been reached. We reanalyzed this apparently controversial problem, approaching it from a Fourier transform representation method combined with some fundamental (basic) ideas found in self-adjoint extensions of symmetric operators. In disagreement with some previous claims, we found that the complete Balmer energy spectrum is obtained together with an odd parity set of eigenfunctions. Closed form solutions in both coordinate and momentum spaces were obtained. No twofold degeneracy was observed as predicted by the degeneracy theorem in one dimension, though it does not necessarily have to hold for potentials with singularities. No ground state with infinite energy exists since the corresponding eigenfunction does not satisfy the Schroedinger equation at the origin.Comment: Accepted for publication in the Canadian Journal of Physics, July 28th, 200

The Association between Symptom Accommodation and Emotional Coregulation in Couples with Binge Eating Disorder

Intense negative emotions and maladaptive behavioral strategies to reduce emotional distress occur not only in patients with various forms of psychopathology but also in their committed partners. One common strategy to reduce distress is for partners to accommodate to the symptoms of the disorder, which reduces distress short term but maintains symptoms long term. Accommodation is believed to be motivated by the partner reacting behaviorally to the patient's emotions, but the emotions of the partner in this context have yet to be examined. This pilot study examined how partner accommodation related to specific patterns of emotional coregulation between patients with binge eating disorder (BED) and their partners, before and after a couple-based intervention for BED. Vocally encoded emotional arousal was measured during couples’ (n = 11) conversations about BED. As predicted, partners’ emotional reactivity to patients’ emotional arousal was associated with high accommodation before treatment. Thus, partners may use accommodation as a strategy to reduce both the patients’ and their own distress. After treatment, partners’ arousal was no longer associated with the patients’ emotional arousal; instead, partners showed greater emotional stability over time, specifically when accommodation was low. Additionally, patients were less emotionally aroused after treatment. Therefore, treatment may have decreased overall emotionality of patients and altered the association between accommodation and partners’ emotional reactivity. If replicated, this understanding of the emotional context associated with accommodation in BED can inform couple-based treatment by targeting specific emotional precipitants of behaviors that maintain symptoms

A pilot open trial of UNITE-BED: A couple-based intervention for binge-eating disorder

Objective: To evaluate the feasibility, acceptability, and preliminary efficacy of a couple-based intervention for binge-eating disorder (BED), called UNiting couples In the Treatment of Eating disorders-BED edition (UNITE-BED). Method: In an open pilot trial, 11 couples in which one or both adult partners had a diagnosis of DSM-5 threshold or sub-threshold BED participated in 22 weekly sessions of UNITE-BED. Patients also received individual treatment, outside of the context of the trial. Couples completed measures on treatment satisfaction, eating disorder symptom severity, depression, anxiety, emotion regulation, and relational functioning at post-treatment and 3-month follow-up. Statistical analyses were conducted to identify change over the course of treatment. Results: UNITE was feasible and acceptable to the majority of couples (9% dropout; high satisfaction ratings). Objective binge abstinence was 81.8% and subjective binge abstinence was 45.5% by post-treatment. Patient binge-eating symptomatology reduced over the course of treatment with results maintained at follow up. Patients' depression symptoms decreased and patients' emotion regulation improved at both time points. Discussion: Including partners in treatment for BED may be beneficial. Results support further evaluation of the efficacy of couple-based interventions for BED in larger randomized-controlled trials

Electronic Structure of the BaFe2_2As2_2 Family of Iron Pnictides

We use high resolution angle-resolved photoemission spectroscopy to study the band structure and Fermi surface topology of the BaFe$_2$As$_2$ iron pnictides. We observe two electron bands and two hole bands near the X-point, $(\pi,\pi)$ of the Brillouin zone, in the paramagnetic state for different doping levels, including electron-doped Ba(Co$_{0.06}$Fe$_{0.94}$)$_2$As$_2$, undoped BaFe$_2$As$_2$, and hole-doped Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$. Among these four bands, only the electron bands cross the Fermi level, forming two electron pockets around X, while the hole bands approach but never reach the Fermi level. We show that the band structure of the BaFe$_2$As$_2$ family matches reasonably well with the prediction of LDA calculations after a momentum-dependent shift and renormalization. Our finding resolves a number of inconsistencies regarding the electronic structure of pnictides.Comment: 5 pages, 4 figure

Temperature and Frequency Dependence of Complex Conductance of Ultrathin YBa2Cu3O7-x Films: A Study of Vortex-Antivortex Pair Unbinding

We have studied the temperature dependencies of the complex sheet conductance of 1-3 unit cell (UC) thick YBa2Cu3O7-x films sandwiched between semiconducting Pr0.6Y0.4Ba2Cu3O7-x layers at high frequencies. Experiments have been carried out in a frequency range between: 2 - 30 MHz with one-spiral coil technique, 100 MHz - 1 GHz frequency range with a new technique using the spiral coil cavity and at 30 GHz by aid of a resonant cavity technique. The real and imaginary parts of the mutual-inductance between a coil and a film were measured and converted to complex conductivity by aid of the inversion procedure. We have found a quadratic temperature dependence of the kinetic inductance, L_k^-1(T), at low temperatures independent of frequency, with a break in slope at T^dc_BKT, the maximum of real part of conductance and a large shift of the break temperature and the maximum position to higher temperatures with increasing frequency. We obtain from these data the universal ratio T^dc_BKT/L_k^-1(T^dc_BKT) = 25, 25, and 17 nHK for 1-, 2- and 3UC films, respectively in close agreement with theoretical prediction of 12 nHK for vortex-antivortex unbinding transition. The activated temperature dependence of the vortex diffusion constant was observed and discussed in the framework of vortex-antivortex pair pinning. PACS numbers: 74.80.Dm, 74.25.Nf, 74.72.Bk, 74.76.BzComment: PDF file, 10 pages, 6 figures, to be published in J. Low Temp. Phys.; Proc. of NATO ARW: VORTEX 200

A grid-based map for the biogeographical regions of Europe

© Pensoft Publishers. Background Biogeographical units are widely adopted in ecological research and nature conservation management, even though biogeographical regionalisation is still under scientific debate. The European Environment Agency provided an official map of the European Biogeographical Regions (EBRs), which contains the official boundaries used in the Habitats and Birds Directives. However, these boundaries bisect cells in the official EU 10 km x 10 km grid used for many purposes, including reporting species and habitat data, meaning that 6881 cells overlap two or more regions. Therefore, superimposing the EBRs vector map over the grid creates ambiguities in associating some cells with European Biogeographical Regions. New information To provide an operational tool to unambiguously define the boundaries of the eleven European Biogeographical Regions, we provide a specifically developed raster map of Grid-Based European Biogeographical Regions (GB-EBRs). In this new map, the borders of the EBRs are reshaped to coherently match the standard European 10 km x 10 km grid imposed for reporting tasks by Article 17 of the Habitats Directive and used for many other datasets. We assign each cell to the EBR with the largest area within the cell