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About a decade ago we proposed a new Microscopic–Macroscopic (Mic–Mac) model where the semiclassical Wigner–Kirkwood expansion of the energy up to fourth-order in ħ is used to compute the shell corrections in a deformed Woods-Saxon potential instead of the usual Strutinsky averaging scheme [1-2]. For a set of 551 even-even nuclei computed with this new model, we found a rms deviation of 610 keV from the experimental masses, similar to the value obtained using the well-known Finite Range Droplet Model and the Lublin–Strasbourg Drop Model for the same set of nuclei. In a next step, we compute the ground-state properties of these 551 nuclei with the same method but using the mean-field provided by the Gogny forces within an Extended Thomas-Fermi approximation. We find that this Mic–Mac model using the Gogny D1S (D1M) force gives a fairly good description of the ground-state energies with a rms deviation of 834 keV (819 keV). This implies that Mic–Mac models based on effective two-body forces, for example Gogny D1S and D1M interactions, perform practically as well as the most efficient Mic–Mac models regarding ground-state properties. [ABSTRACT FROM AUTHOR]

We study the average and global pairing behaviours of electronic devices, like films, wires, and grains using semiclassical methods, such as Weyl and Thomas–Fermi approximations, in the ultrasmall, i.e., quantal regime, which exhibits strong quantum fluctuations and shell effects. We discuss how these results, mostly analytic, are elaborated for average size dependencies, in order to be used in other circumstances when the fully quantal calculation become computationally too expensive. We also compare the results with latest experimental one where possible. [ABSTRACT FROM AUTHOR]

The foundation and applications of the Barcelona Catania Paris Madrid (BCPM) energy density functional are briefly reviewed. BCPM uses a paradigm more rooted on density functional theory and fits most of its parameters to sophisticated microscopic nuclear matter calculations. Finite nuclei are accounted for by introducing a direct finite range surface term, spin orbit potential, Coulomb interaction and pairing. Applications of this functional to the calculation of finite nuclei properties are presented as well as applications to the description of neutron star physics. The large number of applications discussed are possible because of the local character of the functional that simplifies enormously calculations in finite nuclei. [ABSTRACT FROM AUTHOR]

The impact of an enhanced recovery after surgery (ERAS) programme in emergency colorectal surgery has not yet been reported. The objective of this study was to evaluate the feasibility and the results of patients included in an ERAS protocol following emergency colon surgery for left colon perforation. For this purpose, patients with a low to moderate risk of mortality, according to a Peritonitis Severity Score (PSS), and treated with an ERAS protocol (ERAS group) after emergency surgery for left colon perforation were compared for a period of 40 months (March 2014–June 2017) with a control group of patients treated with conventional care (CC group) during the 38 months prior to implementation of the new ERAS protocol (January 2011–February 2014). The main endpoint was 90-day postoperative morbidity according to the Clavien–Dindo classification. Secondary endpoints included length of postoperative hospital stay, 90-day readmission rate, protocol compliance and mortality. Fifty patients were included in the study, 29 in the ERAS group and 21 in the CC group. There were no significant differences between the groups in the demographic data or in the operative characteristics. A reduction in the incidence of postoperative complications (20.7% vs. 38%; p > 0.05) and in the postoperative hospital stay (7.7 + /- 3.85 vs. 10.9 + /- 5.6 days; p = 0.009) were observed in the ERAS group. The 90-day readmission rate did not differ significantly between the two groups (2 vs. 1). No 90-day mortality was observed in either group. The ERAS group showed better results than the CC group in protocol compliance. We conclude that ERAS protocols are feasible and help to reduce morbidity and length of hospital stay without adversely affecting the rate of readmission or mortality. [ABSTRACT FROM AUTHOR]

A theoretical study of even-even nuclei (2 ≤ Z ≤ 8) with extreme neutron excess stable with respect to one-neutron emission, including nuclei beyond the neutron drip line (NDL), is performed. The calculations are based on the Hartree-Fock (HF) method with Skyrme forces (SkI2) and allowance for axial deformation and the Bardeen-Cooper-Schrieffer (BCS) pairing approximation. It is shown that beyond the NDL, He and C isotopes form peninsulas of nuclei stable with respect to one-neutron emissions. The restoration of stability beyond the NDL for He and C can be explained by the complete filling of neutron subshells with high angular momentum and the introduction of corresponding neutron levels in the region of discrete bound states. [ABSTRACT FROM AUTHOR]

Within a microscopic approach the structure of Neutron Stars is usually studied by modelling the homogeneous nuclear matter of the core by a suitable Equation of State, based on a many-body theory, and the crust by a functional based on a more phenomenological approach. We present the first calculation of Neutron Star overall structure by adopting for the core an Equation of State derived from the Brueckner-Hartree-Fock theory and for the crust, including the pasta phase, an Energy Density Functional based on the same Equation of State, and which is able to describe accurately the binding energy of nuclei throughout the mass table. Comparison with other approaches is discussed. The relevance of the crust Equation of State for the Neutron Star radius is particularly emphasised. [ABSTRACT FROM AUTHOR]

Properties of even-even nuclei with extreme neutron excess in the vicinity of neutron magic numbers up to and beyond the neutron drip line (NDL) are calculated by the Hartree-Fock (HF) method using Skyrme forces (Ska, SkM*, Sly4, SkI2, SkP) with allowance for axial deformation and BCS-approximation pairing. It is shown that chains of isotones with the neutron numbers N = 32, 58, 82, 126, 184, and 258 beyond the NDL form peninsulas of nuclei stable with respect to emission of one neutron, and occasionally peninsulas of nuclei stable with respect to the emission of two neutrons. The length of these peninsulas in ( N, Z) space depends on the choice of the Skyrme forces, while their locations are at the same N = 32, 58, 82, 126, 184, and 258 and do not depend on the choice of forces. The investigated isotones restore stability beyond the NDL due to the complete filling of subshells with high angular momentum and to the intrusion of corresponding neutron levels in the region of discrete bound states. The stability of the numerical solution to the HF equations for nuclei belonging to the peninsulas of stability is analyzed. [ABSTRACT FROM AUTHOR]

The properties of the ground state of even-even nuclei with extreme neutron excess that are remote from the known neutron drip line (NDL) are calculated. The calculations are based on the Hartree-Fock method with Skyrme forces SkM*, SkI2, Sly4, Ska) with allowance for axial deformation and the BCS pairing approximation. It is shown that the isotone chain at the neutron number N = 126 beyond the NDL forms a peninsula of nuclei that are stable with respect to the emission of one neutron (PNS). The neutron and proton density distributions of the PNS nuclei have spherical symmetry. A mechanism for restoring the stability of nuclei beyond the NDL is discussed. The obtained results are compared with those from Hartree-Fock-Bogoliubov calculations for long isotope chains of Zr and Pd up to the NDL. [ABSTRACT FROM AUTHOR]

Manifestations of the neutron halo in extremely neutron-rich nuclei are investigated by the Hartree-Fock method using the Skyrme forces (SkM*, Ska, Sly4, SkI2) with allowance for axial deformation. The investigated nuclei, which lie beyond the theoretical neutron drip line (NDL), form peninsulas of nuclei stable with respect to one-neutron emission and belong to chains of isotones with the neutron number N = 32, 58, 82, 126, 184, and 258. [ABSTRACT FROM AUTHOR]

The properties of extremely neutron-excessive nuclei with Z ≥ 70, including the region of transuranium elements, are calculated beyond the previously theoretically known neutron drip line (NDL). The calculations are based on the Hartree-Fock approach using Skyrme forces (SkM*, SkI2, SLy4, Ska) with allowance for axial deformation and pairings in the BCS approximation. It is shown that the series of isotones with neutron number N = 258 outside of 2n NDL forms a peninsula of stable nuclei (PSN) with respect to the emission of one neutron. For SkM* forces, a PSN is formed by Rn, Ra, Th, and U nuclides. [ABSTRACT FROM AUTHOR]

On the basis of the Hartree-Fock method as implemented with Skyrme forces ( Ska, SkM*, Sly4, and SkI2) and with allowance for an axial deformation and nucleon pairing in the Bardeen-Cooper-Schrieffer approximation, the properties of extremely neutron-rich even-even nuclei were calculated beyond the neutron drip line known earlier from theoretical calculations. It was shown that the chains of isotopes beyond the neutron drip line that contain N = 32, 58, 82, 126, and 184 neutrons form peninsulas of nuclei stable against the emission of one neutron and, in some cases, peninsulas of nuclei stable against the emission of two neutrons. The neutron- and proton-density distributions in nuclei forming stability peninsulas were found to be spherically symmetric. A mechanism via which the stability of nuclei might be restored beyond the neutron drip line was discussed. A comparison with the results of calculations by the Hartree-Fock-Bogolyubov method was performed for long chains of sulfur and gadolinium isotopes up to the neutron drip line. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate outcomes in the treatment of bilateral inguinal hernia, comparing the laparoscopic totally extraperitoneal (TEP) and open tension-free mesh repair (LICHT) approaches. Methods: We performed a prospective controlled non randomized clinical study in 128 patients with bilateral inguinal hernia over a period of 3 years. LICHT was used in 106 cases (53 patients) while TEP was employed in 150 cases (75 patients). The main outcome measurements were: recurrence rate, operating time, hospital stay and postoperative complications. Results: There were three recurrences (2.3%): two in the LICHT group (3.8%) and one (1.3%) in the TEP group P = NS. The TEP procedure was faster than LICHT repair (48.8 ± 10.8 vs. 70.4 ± 11.2 min) P < 0.01. Postoperative complications were more frequent in LICHT group (16%) than TEP group (5.3%) P < 0.01. Hospital stay was significantly shorter in the TEP group (0.6 ± 0.8 vs. 1.3 ± 1.2 days) P < 0.001. Conclusions: The TEP approach is an effective option for the treatment of bilateral inguinal hernia when performed by experienced surgeons. [ABSTRACT FROM AUTHOR]

The Garvey-Kelson relations (GKRs) are algebraic expressions originally developed to predict nuclear masses. In this paper we show that the GKRs provide a fruitful framework for the prediction of other physical observables that also display a slowly varying dynamics. Based on this concept, we extend the GKRs to the study of nuclear charge radii. The GKRs are tested on 455 out of the approximately 800 nuclei whose charge radius is experimentally known. We find a rms deviation of 0.01fm between the GK predictions and the experimental values. Predictions are provided for 116 nuclei whose charge radius is presently unknown. [ABSTRACT FROM AUTHOR]

The coupled dynamics of the scissors mode and the isovector giant quadrupole resonance are studied using a generalized Wigner function moments method, taking into account pair correlations. Equations ofmotion for angularmomentum, quadrupolemoment, and other relevant collective variables are derived on the basis of the time-dependent Hartree-Fock-Bogolyubov equations. Analytical expressions for energy centroids and transition probabilities are found for the harmonic-oscillator model with the quadrupole-quadrupole residual interaction and monopole pairing force. Deformation dependences of energies and B( M1) values are correctly reproduced. The inclusion of pair correlations leads to a drastic improvement in the description of qualitative and quantitative characteristics of the scissors mode. [ABSTRACT FROM AUTHOR]

The dynamics of the scissors mode and isovector giant quadrupole resonance has been studied using the generalized method of Wigner function moments, taking into account pairing correlations. Analytical expressions for the transition energies and probabilities have been obtained within the harmonic oscillator model with the quadrupole-quadrupole residual interaction and monopole pairing forces. The dependences of the energies and B( M1) values on deformation are correctly reproduced. Consideration of pairing correlations leads to radical improvement in the description of both qualitative and quantitative characteristics of the scissors mode. [ABSTRACT FROM AUTHOR]

We propose first a generalization of the Density Functional Theory. This theory leads to single-particle equations of motion with a quasilocal mean-field operator, which contains a quasiparticle position-dependent effective mass and a spin—orbit potential. The energy density functional is constructed using the extended Thomas—Fermi approximation. Some ground-state properties of doubly magic nuclei are considered within the framework of this approach. Calculations are performed using the finite-range Gogny D1S forces, and the results are compared with the exact Hartree—Fock calculations. Next, we present an extension of the density functional theory to include pairing correlations without formal violation of the particle-number condition. This problem, which is nonlocal, can be simplified by a suitable quasilocal reduction, which is also briefly discussed in this paper. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the outcome of preperitoneal repair using laparoscopic (TEP) and open (OPM) approach in recurrent inguinal hernia.Methods: We performed a prospective controlled nonrandomized clinical study in 188 patients with 207 recurrent inguinal hernias over a period of 5 years. TEP repair was employed for 86 repairs, and OPM was used in 121 procedures. The main outcome measurements were: recurrence rate, operating time, hospital stay, and postoperative complications.Results: There were three recurrences (1.7%). Two in the OPM group (1.8%) and one (1.3%) in the TEP group [ P=NS (not significant)]. The TEP procedure was faster than OPM for unilateral repair (40.8 vs 46.3 min) (P<0.001). Postoperative complications were more frequent in the OPM group (23.9%) than the TEP group (13.9%) ( P=NS). Hospital stay was significantly shorter in the TEP group (1.2 vs 3.9 days) (P<0.001).Conclusions: Preperitoneal approach (open or laparoscopic) seems to be a good option in recurrent inguinal hernia when these procedures are done by experienced surgeons. [ABSTRACT FROM AUTHOR]

Some basic concepts of the statistical description of the nuclear Fermi liquid drop are discussed. The key quantity, the Wigner distribution function corresponding to the one-body density matrix in phase space, is analyzed. Its asymptotic expansion in powers of h, which leads to the Thomas-Fermi approach, is revisited. A survey of nuclear properties whose average value can be derived in Thomas-Fermi approximation is pointed out. [ABSTRACT FROM AUTHOR]

A new method for incorporating the Pauli exclusion principle into the double-folding approach to the heavy-ion potential is proposed. The description of the exchange terms at the level of the semiclassical one-body density matrix is used. It is shown that, in order to take into account Pauli blocking properly, the density matrices of free isolated nuclei must be redefined. A solution to the self-consistent incorporation of Pauli blocking effects in the mean-field nucleus-nucleus potential is obtained in the Thomas-Fermi approximation. [ABSTRACT FROM AUTHOR]

Deuteron properties and P-N elastic scattering in 1 S0 and 3 S1–3 D1 channels are described within the framework of a model containing non-local interactions that take into account quark exchange processes. Comparisons with other theoretical results are also made. [ABSTRACT FROM AUTHOR]

An analysis of helium cluster properties at finite temperature using a phenomenological free energy density has been carried out. We have studied in detail the energetics and the density profile characteristics of hot drops of both helium isotopes containing 70, 112, 168, 240 and 330 atoms. A finite temperature mass formula including volume, surface and curvature terms has been derived. [ABSTRACT FROM AUTHOR]

The Thomas-Fermi method with applications to the nucleus is revisited. Incorporation of new developments like the treatment of fluctuations and correlations and nuclear pairing will be described. Level densities, response functions and density-density correlations are presented explicitly. [ABSTRACT FROM AUTHOR]

The curvature energy coefficient of the nuclear mass formula a is first calculated for the model case of a Fermi gas bounded by an external Woods-Saxon potential. The semiclassical theory of Wigner and Kirkwood is used and a is found to be close to zero. It is, however, shown that this low value is due to the lack of selfconsistency of the potential. When available, the results of the model compare very well with quantal values and the extrapolation to the spherical cavity (billiard) checks with the value for a known from the Balian-Bloch theory. Second, the selfconsistent case is generalised to finite range forces. No indication is found that this modifies the fact that all theoretical values for a are larger than about 7 MeV which is an order of magnitude above the empirical value. [ABSTRACT FROM AUTHOR]

We describe a simple dynamical model for the production of prompt nucleons at the very beginning of a heavy ion collision. Approximations often used in previous calculations (neglect of Pauli blocking, of window velocity and of its extension) have been checked. We apply the model to the calculation of prompt emitted neutrons in incomplete fusion reactions observed on theNe+Ho system at 220, 402 and 700 MeV. Results of the model are extensively discussed. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]