A variational approach to approximate particle number projection with effective forces

Kamlah's second order method for approximate particle number projection is applied for the first time to variational calculations with effective forces. High spin states of normal and superdeformed nuclei have been calculated with the finite range density dependent Gogny force for several nuclei. Advantages and drawbacks of the Kamlah second order method as compared to the Lipkin-Nogami recipe are thoroughly discussed. We find that the Lipkin-Nogami prescription occasionally may fail to find the right energy minimum in the strong pairing regime and that Kamlah's second order approach, though providing better results than the LN one, may break down in some limiting situations.Comment: 16 pages, 8 figure

El “activismo” de los socioscomo catalizador de laresponsabilidad social de la empresa: aplicación a las organizaciones de participación

In this paper we intend to analyse the real application of the shareholders´ voting rights as a means to encourage social commitments among companies. Shareholders activism has succeeded in introducing corporate governance and corporate social responsibility in companies. The current framework of shareholders activism in Spain is analysed. Besides, we tried to answer two research questions: 1. partners in cooperatives do have or may have a significant and active role in implementing CSR in their organizations, which may be different from the shareholders´ role in listed companies; 2. social economy organizations, by their own mission and identity, comply with social demands.Shareholders activism; members; corporate social responsibility; social economy; corporate governance.

On the Solution of the Number-Projected Hartree-Fock-Bogoliubov Equations

The numerical solution of the recently formulated number-projected Hartree-Fock-Bogoliubov equations is studied in an exactly soluble cranked-deformed shell model Hamiltonian. It is found that the solution of these number-projected equations involve similar numerical effort as that of bare HFB. We consider that this is a significant progress in the mean-field studies of the quantum many-body systems. The results of the projected calculations are shown to be in almost complete agreement with the exact solutions of the model Hamiltonian. The phase transition obtained in the HFB theory as a function of the rotational frequency is shown to be smeared out with the projection.Comment: RevTeX, 11 pages, 3 figures. To be published in a special edition of Physics of Atomic Nuclei (former Sov. J. Nucl. Phys.) dedicated to the 90th birthday of A.B. Migda

Cranked Relativistic Hartree-Bogoliubov Theory: Formalism and Application to the Superdeformed Bands in the A∼190A\sim 190 region

Cranked Relativistic Hartree-Bogoliubov theory without and with approximate particle number projection by means of the Lipkin-Nogami method is presented in detail as an extension of Relativistic Mean Field theory with pairing correlations to the rotating frame. Pairing correlations are taken into account by a finite range two-body force of Gogny type. The applicability of this theory to the description of rotating nuclei is studied in detail on the example of superdeformed bands in even-even nuclei of the $A\sim 190$ mass region. Different aspects such as the importance of pairing and particle number projection, the dependence of the results on the parametrization of the RMF Lagrangian and Gogny force etc. are investigated in detail. It is shown that without any adjustment of new parameters the best description of experimental data is obtained by using the well established parameter sets NL1 for the Lagrangian and D1S for the pairing force. Contrary to previous studies at spin zero it is found that the increase of the strength of the Gogny force is not necessary in the framework of Relativistic Hartree-Bogoliubov theory provided that particle number projection is performed.Comment: 34 pages, 24 figures, 3 tables, uses Revtex and epsf.sty, submitted to Nuclear Physics

POS1394 ACCURACY AND PERFORMANCE OF A HANDHELD ULTRASOUND DEVICE TO ASSESS ARTICULAR AND PERIARTICULAR PATHOLOGIES IN PATIENTS WITH INFLAMMATORY ARTHRITIS

Background:Handheld ultrasound (HHUS) devices have increasingly found their way into clinical practice due to several advantages (e.g. portability, significantly lower purchase cost). However, there is no evidence to date on the accuracy and performance of HHUS in patients with inflammatory arthritis (IA).Objectives:To assess accuracy and performance of a new HHUS machine in comparison to a conventional cart-based sonographic machine in patients with IA.Methods:Consecutive IA patients of our outpatient clinic with at least one tender and swollen joint in the 66/68 joint count were enrolled. US was performed on clinically affected joints with corresponding tendons/entheses using a cart-based sonographic device ("Samsung HS40") and a HHUS device ("Butterfly iQ") in standard scan positions. One blinded reader scored all images for the presence of following pathologic findings: erosions, bony enlargement, synovial hyperthrophy, joint effusion, bursitis, tenosynovitis and enthesitis. In addition, synovitis was graded (B Mode and power Doppler (PD)) by the 4-level EULAR-OMERACT scale [1]. To avoid bias by the blinded reader, who otherwise would have been tempted to identify pathological findings for each examined joint, we also included 67 joints of two healthy volunteers into the evaluation. We calculated the overall concordance and the concordance by type of joint and type of pathological finding between the two devices (percentage of observation pairs in which the same rating was given by both devices). The Cohen's kappa coefficient (κ) with 95% bootstrap confidence intervals was used to assess the agreement between the two US devices. We also measured the time required for the US examination of one joint with both devices.Results:32 patients (20 rheumatoid arthritis, 10 psoriatic arthritis, 1 gouty arthritis, 1 systemic lupus erythematosus) were included in this study. Mean age of patients was 58.2±13.7 years, 63% were females. In total 186 joints were examined. The overall raw concordance in B-mode between the two devices was 97 %, with an overall κappa for agreement of 0.90, 95% CI (0.89, 0.94). No significant differences were found in relation to type of joint or pathological finding examined. The PD-mode of the HHUS device did not detect any PD-signal, whereas the cart-based device detected a PD-signal in 61 joints (33%). The portable device did not offer any time saving compared to the cart-based device (mean time in seconds per examined region: 47 seconds for the HHUS device versus 46.3 seconds for the cart-based device).Conclusion:The HHUS device "Butterfly iQ" has been shown to be accurate in the assessment of structural joint damage and inflammation in patients with IA, but only in B-mode. Significant improvements are still needed to reliable demonstrate blood flow detection by PD mode.References:[1]D'Agostino, M.A., et al., RMD Open, 2017. 3(1): p. e000428.Table 1.Concordance between a handheld and a conventional cart-based US device in B-modeAgreement by siteN joints (%)Concordance (%)Kappa 95%CIOverall186970.90 (0.89 to 0.94)Wrist32 (17.2)960.86 (0.77 to 0.93)Finger/toe joint (MCP, PIP, DIP, MTP)114 (61.3)970.92 (0.88 to 0.95)Elbows11 (5.9)950.87 (0.75 to 0.97)Shoulder4 (2.2)1001.00 (NA to NA) *Knee20 (10.7)980.96 (0.90 to 1.00)Ankle5 (2.7)1001.00 (NA to NA) *Agreement by pathological findingJoint effusion950.81 (0.68 to 0.92)Synovitis940.87 (0.79 to 0.93)Synovitis OMERACT grade (0– 3)900.84 (0.76 to 0.91)Bone enlargement980.88 (0.71 to 1.00)Erosion980.89 (0.77 to 0.89)Tenosynovitis980.83 (0.61 to 0.96)Entheseopathy1001.00 (NA to NA) *Bursitis970.90 (0.89 to 0.94)* unreliable kappa statistics because of small number of shoulders/ankles examined and small number of entheseopathiesFigure 1.Pathological US findings in MCP joints (1, 2, 3) and wrist (4) depicted by the two different ultrasound devicesB-mode erosive (arrow) and synovial (asterisk) changes could be detected by both devices (1-2), while PD changes of different grades only by the conventional US device (3-4).Acknowledgements:This study was supported by the Deutsche Forschungsgemeinschaft (DFG- FOR2886 PANDORA and the CRC1181). Additional funding was received by the Bundesministerium für Bildung und Forschung (BMBF; project METARTHROS, MASCARA), the H2020 GA 810316 - 4D-Nanoscope ERC Synergy Project, the IMI funded project RTCure, the Emerging Fields Initiative MIRACLE of the Friedrich-Alexander-Universität Erlangen-Nürnberg, the Else Kröner-Memorial Scholarship (DS, no. 2019_EKMS.27) and Innovationsfond Lehre / FAU Erlangen-Nürnberg 2019.Disclosure of Interests:None declare

Moments of Inertia of Nuclei in the Rare Earth Region: A Relativistic versus Non-Relativistic Investigation

A parameter free investigation of the moments of inertia of ground state rotational bands in well deformed rare-earth nuclei is carried out using Cranked Relativistic Hartree-Bogoliubov (CRHB) and non-relativistic Cranked Hartree-Fock-Bogoliubov (CHFB) theories. In CRHB theory, the relativistic fields are determined by the non-linear Lagrangian with the NL1 force and the pairing interaction by the central part of finite range Gogny D1S force. In CHFB theory, the properties in particle-hole and particle-particle channels are defined solely by Gogny D1S forces. Using an approximate particle number projection before variation by means of the Lipkin Nogami method improves the agreement with the experimental data, especially in CRHB theory. The effect of the particle number projection on the moments of inertia and pairing energies is larger in relativistic than in non-relativistic theory.Comment: 18 pages + 2 PostScript figure

Approximate particle number projection for finite range density dependent forces

The Lipkin-Nogami method is generalized to deal with finite range density dependent forces. New expressions are derived and realistic calculations with the Gogny force are performed for the nuclei $^{164}$Er and $^{168}$Er. The sharp phase transition predicted by the mean field approximation is washed out by the Lipkin-Nogami approach; a much better agreement with the experimental data is reached with the new approach than with the Hartree-Fock_Bogoliubov one, specially at high spins.Comment: 5 pages, RevTeX 3.0, 3 postscript figures included using uufiles. Submitted to Phys. Rev. Let

Mean field theory for global binding systematics

We review some possible improvements of mean field theory for application to nuclear binding systematics. Up to now, microscopic theory has been less successful than models starting from the liquid drop in describing accurately the global binding systematics. We believe that there are good prospects to develop a better global theory, using modern forms of energy density functionals and treating correlation energies systematically by the RPA.Comment: RevTex, 17 pages, 5 eps figures. To be published in Yadernaya Fizika, special edition for the 90th birthday of Professor A.B. Migda