We present the covariance analysis of two successful nuclear energy density functionals (EDFs), (i) a non-relativistic Skyrme functional built from a zero-range effective interaction, and (ii) a ...relativistic nuclear EDF based on density dependent meson-nucleon couplings. The covariance analysis is a useful tool for understanding the limitations of a model, the correlations between observables and the statistical errors. We show, for our selected test nucleus Pb, that when the constraint on a property A included in the fit is relaxed, correlations with other observables B become larger; on the other hand, when a strong constraint is imposed on A, the correlations with other properties become very small. We also provide a brief review, partly connected with the covariance analysis, of some instabilities displayed by several EDFs currently used in nuclear physics.
We review several experimental and theoretical advances that emphasize common aspects of the study of spin-singlet, T = 1, and spin-triplet, T = 0, pairing correlations in nuclei. We first discuss ...various empirical evidence of the special role played by the T = 1 pairing interaction. In particular, we show the peculiar features of the nuclear pairing interaction in the low-density regime, and possible outcomes such as the BCS-BEC crossover in nuclear matter and, in an analogous way, in loosely bound nuclei. We then move to the competition between T = 1 and T = 0 pairing correlations. The effect of such competition on the low-lying spectra is studied in N = Z odd-odd nuclei by using a three-body model; in this case, it is shown that the inversion of the J π = 0 + and J π = 1 + states near the ground state, and the strong magnetic dipole transitions between them, can be considered as a clear manifestation of strong T = 0 pairing correlations in these nuclei. The effect of T = 0 pairing correlations is also quite evident if one studies charge-changing transitions. The Gamow-Teller (GT) states in N = Z + 2 nuclei are studied here by using self-consistent Hartree-Fock-Bogoliubov (HFB) plus quasiparticle random-phase approximation calculations in which the T = 0 pairing interaction is taken into account. Strong GT states are found, near the ground state of daughter nuclei; these are compared with available experimental data from charge-exchange reactions, and such comparison can pinpoint the value of the strength of the T = 0 interaction. Pair transfer reactions are eventually discussed. While two-neutron transfer has long been proposed as a tool to measure the T = 1 superfluidity in the nuclear ground states, the study of deuteron transfer is still in its infancy, despite its potential interest for revealing effects coming from both T = 1 and T = 0 interactions. We also point out that the reaction mechanism may mask the strong pair transfer amplitudes predicted by the HFB calculations, because of the complexity arising from simultaneous and sequential pair transfer processes.
.
The couplings between particles and vibrations in atomic nuclei play a key role in the understanding of various nuclear properties, as it has been highlighted along several decades. In this ...contribution, after a short survey of the early discoveries of particle-phonon multiplets around the
208
Pb region, we review recent experiments and theoretical attempts to understand low-energy spectra of odd-nuclei close to magic and semi-magic cores, where particle-phonon coupling phenomena play a significant role. The focus will be on nuclei around
48
Ca ,
132
Sn ,
208
Pb and neutron-rich Ni isotopes. Special emphasis will be given to experimental techniques based on high-resolution
γ
-spectroscopy and to recent theoretical developments aimed at disentangling particle-phonon coupled states and other more hybrid configurations, using the Hybrid Configuration Mixing model that has been recently proposed by the Milano group.
Background
Minimally invasive surgery (MIS) in medial displacement calcaneus osteotomy (MDCO) has been proposed for surgical correction of adult-acquired flat foot deformity (AAFD) to reduce ...complications of open approaches. The aim of our study is to systematically analyze complications and the clinical and radiological results of MIS- MDCO.
Methods
A systematic review of the English literature was performed on 30th October 2023. Randomized controlled trials and non-randomized trials, cohort studies, case–control studies and case series concerning surgical correction of AAFD with MIS-MDCO and with at least 15 patients were included. Case reports, technical notes, animal or cadaveric studies were excluded. The quality and risk of bias of the studies included were evaluated using GRADE and MINORS systems. Complications rate, clinical and radiological results were inferred from the studies included.
Results
Nine articles were included. A total of 501 cases treated with MIS-MDCO were analysed with a mean follow-up of 11.9 ± 5.1 months. The reported wound infection rate was about 3% and sural neuropathy was rated about 1%. Only 4% of the cases required removal of the screw for pain. In the comparative studies (MIS versus Open MDCO), comparable clinical results but with significant differences (
P
< 0.001) in infection rates (1% versus 14%) and sural neuropathy (2% versus 1%) were observed.
Conclusion
AAFD correction performed with MIS-MDCO, with the limitation of a poor quality and high risk of bias of the included studies, seems to provide good clinical results and high subjective satisfaction with a lower complication rate compared to open approach. Further high-quality long-term comparative studies could better clarify complications and clinical and radiological outcomes of the MIS technique in the treatment of AAFD.
Level of evidence
Level IV.
The dipole polarizability of stable even-mass tin isotopes 112,114,116,118,120,124Sn was extracted from inelastic proton scattering experiments at 295MeV under very forward angles performed at RCNP. ...Predictions from energy density functionals cannot account for the present data and the polarizability of 208Pb simultaneously. The evolution of the polarizabilities in neighboring isotopes indicates a kink at 120Sn while all model results show a nearly linear increase with mass number after inclusion of pairing corrections.
The model dependence in the correlations of the neutron-skin thickness in heavy nuclei with various symmetry-energy parameters is analyzed by using several families of systematically varied ...microscopic mean-field models. Such correlations show a varying degree of model dependence once the results for all the different families are combined. Some mean-field models associated with similar values of the symmetry-energy slope parameter at saturation density L , and pertaining to different families, yield a greater-than-expected spread in the neutron-skin thickness of the 208 Pb nucleus. The effective value of the symmetry-energy slope parameter L eff , determined by using the nucleon density profiles of the finite nucleus and the density derivative S ′ ( ρ ) of the symmetry energy starting from about saturation density up to low densities typical of the surface of nuclei, seems to account for the spread in the neutron-skin thickness for the models with similar L . The differences in the values of L eff are mainly due to the small differences in the nucleon density distributions of heavy nuclei in the surface region and the behavior of the symmetry energy at subsaturation densities.
Hallux valgus (HV) is a frequent forefoot deformity affecting about 23% of adults and 35.7% of people over 65. The exact etiology is not fully understood. The first ray plays a significant role in ...walking cause it bears the principal amount of weight and maintains the position of the medial arch. Several factors that deteriorate the integrality of the first ray, such as foot deformities, restrictive footwear, and pes planus, may be ascribed to the HV occurrence. Before any surgical correction, conservative treatment should always be initiated first. Currently, there is no consensus that conservative management by shoe modification and foot orthoses could correct the pathology or terminate the clinical worsening of the condition.From a careful analysis of the literature, proper footwear should be a shoe with an adequate length, wide toe box, cushioned sole, and a lowered heel to not increase the load on the metatarsal heads and cause pain. Personalized 3D printed customized toe spreaders may be applied in patients with HV, improving symptoms and bringing pain relief. Compensating the subtalar joint hyperpronation through foot orthoses plays a fundamental role in the HV development, preventing or at least controlling the condition's progress; this, along with weight reduction and regular physical activity.Data obtained suggest that dynamic foot orthoses prefer a biomechanical type with 3/4-length, which is less likely to negatively affect the dorsal or medial pressures, which instead were noted to increase with the sulcus- and full-length orthoses.Although some studies suggest that foot orthoses would favor the correction of HV deformity, results have been very variable and just in few studies appear to correct HV or reduce its progression, improving symptoms and bringing pain relief. In the case of HV surgical correction, orthoses seem to maintain the correct position acquired over time.Hallux valgus (HV) is a frequent forefoot deformity affecting about 23% of adults and 35.7% of people over 65. The exact etiology is not fully understood. The first ray plays a significant role in walking cause it bears the principal amount of weight and maintains the position of the medial arch. Several factors that deteriorate the integrality of the first ray, such as foot deformities, restrictive footwear, and pes planus, may be ascribed to the HV occurrence. Before any surgical correction, conservative treatment should always be initiated first. Currently, there is no consensus that conservative management by shoe modification and foot orthoses could correct the pathology or terminate the clinical worsening of the condition.From a careful analysis of the literature, proper footwear should be a shoe with an adequate length, wide toe box, cushioned sole, and a lowered heel to not increase the load on the metatarsal heads and cause pain. Personalized 3D printed customized toe spreaders may be applied in patients with HV, improving symptoms and bringing pain relief. Compensating the subtalar joint hyperpronation through foot orthoses plays a fundamental role in the HV development, preventing or at least controlling the condition's progress; this, along with weight reduction and regular physical activity.Data obtained suggest that dynamic foot orthoses prefer a biomechanical type with 3/4-length, which is less likely to negatively affect the dorsal or medial pressures, which instead were noted to increase with the sulcus- and full-length orthoses.Although some studies suggest that foot orthoses would favor the correction of HV deformity, results have been very variable and just in few studies appear to correct HV or reduce its progression, improving symptoms and bringing pain relief. In the case of HV surgical correction, orthoses seem to maintain the correct position acquired over time.
We analyze and propose a solution to the apparent inconsistency between our current knowledge of the equation of state of asymmetric nuclear matter, the energy of the isobaric analog state (IAS) in a ...heavy nucleus such as ^{208}Pb, and the isospin symmetry breaking forces in the nuclear medium. This is achieved by performing state-of-the-art Hartree-Fock plus random phase approximation calculations of the IAS that include all isospin symmetry breaking contributions. To this aim, we propose a new effective interaction that is successful in reproducing the IAS excitation energy without compromising other properties of finite nuclei.
The goal of nuclear structure physics is to provide a complete understanding of the static properties of atomic nuclei, their excitation spectra, their response to external fields and their decays. ...While it is hard to achieve these goals within a single framework, so that there is no nuclear 'standard model', it is clear that nuclear Density Functional Theory (DFT) has probably the widest range of applicability so far. In this paper, we try to put DFT in a broader context, with frequent comparisons to electronic DFT. We also include a discussion of the relationships with ab initio methods and Effective Field Theories (EFTs) in general, as well as a short survey of the quite large number of applications. Although written with a personal and possibly biased perspective, the paper aims at fostering cross-fertilizations with other domains of science.
The first 2+ and 3- states of the doubly magic nucleus Sn132 are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the ...highly efficient MINIBALL array. The Sn132 ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a Pb206 target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0g.s.+→21+, 0g.s.+→31-, and 21+→31- in Sn132. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0g.s.+→21+) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of Sn132.
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