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The method of relative self absorption is based on the technique of nuclear resonance fluorescence measurements. It allows for a model-independent determination of ground-state transition widths, natural level widths, and, consequently, of branching ratios to the ground state for individual excitations. Relative self–absorption experiments have been performed on the nuclei 6Li and 140Ce. In order to investigate the total level width for the 0+1, T = 1 level at 3563 keV in 6Li, a high-precision self-absorption measurement has been performed. In the case of 140Ce, self absorption has been applied for the first time to study decay widths of dipole-excited states in the energy regime of the pygmy dipole resonance.

In the present work, we investigate the bulk properties of nuclear matter and neutron stars with the newly proposed relativistic interaction NL-RS which provides an opportunity to readjust the coupling constants keeping in view the properties of finite nuclei, nuclear matter, PREX-II results for neutron skin thickness in 208Pb and astrophysical observations. The NL-RS model interaction has been proposed by fitting the ground state properties (binding energies and charge radii) of finite nuclei, bulk nuclear matter properties, and PREX-II results for neutron skin thickness of 208Pb. The relativistic interaction has been generated by including nonlinear self-interactions of σ and ω μ -mesons and mixed interactions of ω μ , and ρ μ -meson up to the quartic order. The proposed interaction harmonizes with the finite nuclei, bulk nuclear matter, and neutron star properties. A covariance analysis is performed to assess the statistical uncertainties on the model parameters and nuclear observables of interest along with correlations amongst them. The equation of state (EoS) composed of nucleons and leptons in β -equilibrium is computed with the proposed parameter set and used to study the neutron star structure. The maximum mass of the neutron star by employing the EoS computed with the NL-RS parameter set is 2.04 ± 0.03 M ⊙ and the radius of a canonical mass neutron star (R 1.4) comes out to be equal to 13.06 ± 0.16 Km. The value of dimensionless tidal deformability, for canonical mass, is 602.23 ± 33.13 which satisfies the constraints of waveform models analysis of GW170817 within 90% confidence level. [ABSTRACT FROM AUTHOR]

The concept of symmetry under various transformations of quantities describing basic natural phenomena is one of the fundamental principles in the mathematical formulation of physical laws. Starting with Noether's theorems, we highlight some well–known examples of global symmetries and symmetry breaking on the particle level, such as the separation of strong and electroweak interactions and the Higgs mechanism, which gives mass to leptons and quarks. The relation between symmetry energy and charge symmetry breaking at both the nuclear level (under the interchange of protons and neutrons) and the particle level (under the interchange of u and d quarks) forms the main subject of this work. We trace the concept of symmetry energy from its introduction in the simple semi-empirical mass formula and liquid drop models to the most sophisticated non-relativistic, relativistic, and ab initio models. Methods used to extract symmetry energy attributes, utilizing the most significant combined terrestrial and astrophysical data and theoretical predictions, are reviewed. This includes properties of finite nuclei, heavy-ion collisions, neutron stars, gravitational waves, and parity–violating electron scattering experiments such as CREX and PREX, for which selected examples are provided. Finally, future approaches to investigation of the symmetry energy and its properties are discussed. [ABSTRACT FROM AUTHOR]

Overlapping uranium and coal resources are widely distributed in the basins of China. The current uranium–coal coordinated mining model, mining interaction, and multi-phase and multi-field coupling mechanisms remain unclear, thereby substantially restricting the mining of overlapping uranium and coal resources. This article reviews the overlapping uranium–coal mining technology and conditions, summarizes the main problems faced by the coordinated mining of coexisting uranium–coal resources, proposes a dynamic coordinated mining technology system for the entire life cycle of coexisting uranium–coal resources, and describes the multiphase and multifield coordinated mining of co-associated uranium–coal resources. The multifield coupling mechanism clarifies the solid–liquid–gas three-phase spatiotemporal coupling effects of the stress, fracture, seepage, geochemical, pressure, and microbial fields, and explains the safe and efficient mining technology of uranium and coal resources, and the coordinated mining and isolation technology of uranium and coal. "Trinity" pollution prevention and control technology and other key research directions are discussed to promote green, efficient, joint, and coordinated mining of uranium and coal. [ABSTRACT FROM AUTHOR]

Recently, a novel approach has been proposed to produce ultrashort, fully coherent high-repetition-rate EUVand X-ray radiation by combining an energy recovery linac (ERL) with the angular-dispersion-induced microbunching methodology. It is critical to maintain microbunching when the beam passes through bending magnets between the undulators, which results in difficulties supporting multiple beamlines. In this paper, the design of a multiplexed emitting system consisting of multi-bend achromats, matching sections and radiators to facilitate the multi-beamline operation is presented. Theoretical analysis and numerical simulations have been carried out and the results show that the microbunching and beam quality can be well maintained after four times of bending. Five radiation pulses with a central wavelength of 13.5 nm and peak power at theMW level have been produced by the same electron beam via this multiplexed emitting system. The proposed method holds potential in the multi-beamline operation of ERL- or storage-ring-based coherent light sources. [ABSTRACT FROM AUTHOR]

A review is made of constraints on the nuclear symmetry energy parameters arising from nuclear binding energy measurements, theoretical chiral effective field predictions of neutron matter properties, the unitary gas conjecture, and measurements of neutron skin thicknesses and dipole polarizabilities. While most studies have been confined to the parameters S V and L, the important roles played by, and constraints on K sym , or, equivalently, the neutron matter incompressibility K N , are discussed. Strong correlations among S V , L , and K N are found from both nuclear binding energies and neutron matter theory. However, these correlations somewhat differ in the two cases, and those from neutron matter theory have smaller uncertainties. To 68% confidence, it is found from neutron matter theory that S V = 32.0 ± 1.1 MeV, L = 51.9 ± 7.9 MeV and K N = 152.2 ± 38.1 MeV. Theoretical predictions for neutron skin thickness and dipole polarizability measurements of the neutron-rich nuclei 48 Ca, 120 Sn, and 208 Pb are compared to recent experimental measurements, most notably the CREX and PREX neutron skin experiments from Jefferson Laboratory. By themselves, PREX I+II measurements of 208 Pb and CREX measurement of 48 Ca suggest L = 121 ± 47 MeV and L = − 5 ± 40 MeV, respectively, to 68% confidence. However, we show that nuclear interactions optimally satisfying both measurements imply L = 53 ± 13 MeV, nearly the range suggested by either nuclear mass measurements or neutron matter theory, and is also consistent with nuclear dipole polarizability measurements. This small parameter range implies R 1.4 = 11.6 ± 1.0 km and Λ 1.4 = 228 − 90 + 148 , which are consistent with NICER X-ray and LIGO/Virgo gravitational wave observations of neutron stars. [ABSTRACT FROM AUTHOR]

Background and Objectives: Characterising the features of methodologies, clinical attributes and intervention protocols, of studies is valuable to advise directions for research and practice. This article reports the findings of a secondary analysis of the features from studies screened as part of a large systematic review of TENS (the meta-TENS study). Materials and Methods: A descriptive analysis was performed on information associated with methodology, sample populations and intervention protocols from 381 randomised controlled trials (24,532 participants) evaluating TENS delivered at a strong comfortable intensity at the painful site in adults with pain, irrespective of diagnosis. Results: Studies were conducted in 43 countries commonly using parallel group design (n = 334) and one comparator group (n = 231). Mean ± standard deviation (SD) study sample size (64.05 ± 58.29 participants) and TENS group size (27.67 ± 21.90 participants) were small, with only 13 of 381 studies having 100 participants or more in the TENS group. Most TENS interventions were 'high frequency' (>10 pps, n = 276) and using 100 Hz (109/353 reports that stated a pulse frequency value). Of 476 comparator groups, 54.2% were active treatments (i.e., analgesic medication(s), exercise, manual therapies and electrophysical agents). Of 202 placebo comparator groups, 155 used a TENS device that did not deliver currents. At least 216 of 383 study groups were able to access other treatments whilst receiving TENS. Only 136 out of 381 reports included a statement about adverse events. Conclusions: Clinical studies on TENS are dominated by small parallel group evaluations of high frequency TENS that are often contaminated by concurrent treatment(s). Study reports tended focus on physiological and clinical implications rather than the veracity of methodology and findings. Previously published criteria for designing and reporting TENS studies were neglected and this should be corrected in future research using insights gleaned from this analysis. [ABSTRACT FROM AUTHOR]

The Daejeon16 two-nucleon interaction is employed in many-body approaches based on the mean-field approximation. The perturbative character of Daejeon16 is verified by comparing results for 16O from the Hartree–Fock (HF) approximation and from the no-core shell model and by examining the magnitude of perturbative corrections to the HF energy in light and heavy nuclei. In order to approximately describe energies and radii across the nuclear chart, a phenomenological correction in the form of a two-plus-three-nucleon contact interaction is introduced. With fitted parameters we achieve a very good description of medium-mass nuclei in terms of energy and size and also in terms of the centroid energy of the giant monopole resonance and the dipole polarizability calculated within the random-phase approximation. Our results provide further justification for the use of Daejeon16 augmented with phenomenological corrections as an effective interaction of perturbative character in a variety of applications. [ABSTRACT FROM AUTHOR]

Magnetic dipole (M1) excitation is the leading mode of multi-nucleon excitations induced by the magnetic field, and is a phenomenon of the spin–orbit splitting and residual interactions involved. In this work, we investigate the effects of the residual interactions on the M1 excitation from a novel perspective, the framework of relativistic nuclear energy-density functional. The relativistic Hartree–Bogoliubov model is utilized to determine the nuclear ground state properties, while the relativistic quasi-particle random-phase approximation is employed for the description of M1-excitation properties. From the analysis of M1 mode in the Ca isotope chain, role of the isovector–pseudovector residual interaction is discussed. For open-shell nuclei, the pairing correlation also plays a noticeable role in the M1 mode. The experimental data on M1 mode is expected to provide a suitable reference to improve and optimize the theoretical models to describe the residual interactions. [ABSTRACT FROM AUTHOR]

A novel method of variation after |$K$| -projection is proposed to study dipole excitations in the framework of antisymmetrized molecular dynamics with the |$\beta$| -constraint. The method is applied to |$^{10}$| Be and |$^{16}$| O to describe low-energy dipole excitations. In the application to |${}^{10}\textrm{Be}$|⁠ , two dipole states in the low-energy region are obtained. For |${}^{16}\textrm{O}$|⁠ , the |$1_1^-$| and |$1_2^-$| states are obtained with remarkable dipole strength. The |$1_1^-$| state is characterized by significant toroidal dipole (TD) strength and compressional dipole strength, whereas the |$1_2^-$| state has significant TD strength and shows a developed |$\alpha + {}^{12}\textrm{C}$| cluster structure. Dipole properties in |$^{16}$| O are discussed by analyzing the current densities of the dipole transitions. [ABSTRACT FROM AUTHOR]

Second-order processes in physics is a research topic focusing attention from several fields worldwide including, for example, non-linear quantum electrodynamics with high-power lasers, neutrinoless double-β decay, and stimulated atomic two-photon transitions. For the electromagnetic nuclear interaction, the observation of the competitive double-γ decay from 137mBa has opened up the nuclear structure field for detailed investigation of second-order processes through the manifestation of off-diagonal nuclear polarisability. Here, we confirm this observation with an 8.7σ significance, and an improved value on the double-photon versus single-photon branching ratio as 2.62 × 10−6(30). Our results, however, contradict the conclusions from the original experiment, where the decay was interpreted to be dominated by a quadrupole-quadrupole component. Here, we find a substantial enhancement in the energy distribution consistent with a dominating octupole-dipole character and a rather small quadrupole-quadrupole component in the decay, hindered due to an evolution of the internal nuclear structure. The implied strongly hindered double-photon branching in 137mBa opens up the possibility of the double-photon branching as a feasible tool for nuclear-structure studies on off-diagonal polarisability in nuclei where this hindrance is not present. Second order effects can play an important role in highlighting nuclear structure properties. Here, the authors show how the second-order nuclear transitions in the form of double-gamma decay in 137Ba help understanding atomic nuclei. [ABSTRACT FROM AUTHOR]

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Since 2013, the mass of pulsar PSR J0348 + 0432 (M = 2.01M⊙) has provided a tight constraint on neutron star (NS) equation of state. However, a number of different analyses of the recently detected binary neutron star (BNS) merger (GW170817) point to a maximum NS mass around 2.16M⊙. In addition, a recent study determined the mass of the millisecond pulsar PSR J2215 + 5135 to be 2.27−0.15+0.17M⊙. In this work, we investigate the presence of hyperons in NS matter in light of these new mass measurements using equations of state calculated in the relativistic mean‐field approximation. Particular attention is paid to the use of the available empirical data from the study of hypernuclei and that of the SU(3) symmetry relations in fixing the meson‐hyperon coupling constants. We find that hyperonic equations of state with reasonable choices for the meson‐hyperon coupling constants can satisfy these new mass constraints, with hyperons potentially accounting for more than 10% of the baryons in the core of a NS. [ABSTRACT FROM AUTHOR]

Background: Older persons with earlier trauma are often more vulnerable to stresses of old age. Aims: To examine the levels of emotional distress in relation to cognitive appraisal of acute hospitalization and coping strategies in Holocaust survivors compared with an age- and education-matched group of elderly persons without Holocaust experience. Methods: This is a cross-sectional study of 63 Holocaust survivors, 65 years and older, hospitalized for an acute illness, and 57 age-, education- and hospital unit-matched people without Holocaust experience. Participants completed appraisal and coping strategies (COPE) questionnaires, and the brief symptoms inventory (BSI-18). Results: Holocaust survivors reported higher levels of emotional distress, appraised the hospitalization higher as a threat and lower as a challenge, and used more emotion-focused and less problem-focused or support-seeking coping strategies than the comparison group. Study variables explained 65% of the variance of emotional distress; significant predictors of emotional distress in the final regression model were not having a partner and more use of emotion-focused coping. The latter mediated the relation of group variable and challenge appraisal to emotional distress. Conclusions: Health professionals must be aware of the potential impact of the hospital environment on the survivors of Holocaust as well as survivors of other trauma. Being sensitive to their specific needs may reduce the negative impact of hospitalization. [ABSTRACT FROM AUTHOR]

The article offers information on a study conducted on socioeconomic conditions and number of pain sites (NPS) in women, as they are deprived of socioeconomic conditions. It states that the final sample comprised of 319 gynecological cancer survivors and 1276 women from general population. It mentions that more women reporting 3 NPS had high body mass index (BMI), and women reporting 4-7 NPS were more often single, had lower education and had lower income.

Background: It has been argued that placebos may not have important clinical impacts in general. However, there is increasing evidence of a publication bias among trials published in journals. Therefore, we explored the potential for publication bias in randomized trials with active treatment, placebo, and no-treatment groups. Methods: Three-armed randomized trials of acupuncture, acupoint stimulation, and transcutaneous electrical stimulation were obtained from electronic databases. Effect sizes between treatment and placebo groups were calculated for treatment effect, and effect sizes between placebo and no-treatment groups were calculated for placebo effect. All data were then analyzed for publication bias. Results: For the treatment effect, small trials with fewer than 100 patients per arm showed more benefits than large trials with at least 100 patients per arm in acupuncture and acupoint stimulation. For the placebo effect, no differences were found between large and small trials. Further analyses showed that the treatment effect in acupuncture and acupoint stimulation may be subject to publication bias because study design and any known factors of heterogeneity were not associated with the small study effects. In the simulation, the magnitude of the placebo effect was smaller than that calculated after considering publication bias. Conclusions: Randomized three-armed trials, which are necessary for estimating the placebo effect, may be subject to publication bias. If the magnitude of the placebo effect is assessed in an intervention, the potential for publication bias should be investigated using data related to the treatment effect. [ABSTRACT FROM AUTHOR]

This study explores current expressions of past trauma among Holocaust survi vors. Medical records and extensive interviews were analyzed for 38 Holocaust survivors who were hospitalized and/or under ambulatory care. The sample consisted of 55% women and 45% men whose mean age was 72 (SD = 9.2). Expressions of Holocaust experience yielded two factors: Holocaust-as-Present (e.g., feeling the Holocaust experience as continuing, Holocaust-related somatization) and Holocaust-as-Past (e.g., avoiding preoccupation with traumatic memories, feeling unduly stigmatized as a survivor). The results indicate that mental symptoms and the number of medical diagnoses are positively correlated with Holocaust-as-Present but negatively correlated with Holocaust-as-Past. However, scoring high on Holocaust-as-Past relates to a higher danger to life as a result of significant morbidity. The findings suggest two differential modes of either remaining enmeshed in the traumatic experience or attempting to contain the sequelae of the trauma. These modes differ in their implications for mental and physical health. [ABSTRACT FROM AUTHOR]

The effective Gogny interactions of the D1 family were established by D. Gogny more than forty years ago with the aim to describe simultaneously the mean field and the pairing field corresponding to the nuclear interaction. The most popular Gogny parametrizations, namely D1S, D1N and D1M, describe accurately the ground-state properties of spherical and deformed finite nuclei all across the mass table obtained with Hartree–Fock–Bogoliubov (HFB) calculations. However, these forces produce a rather soft equation of state (EoS) in neutron matter, which leads to predict maximum masses of neutron stars well below the observed value of two solar masses. To remove this limitation, we built new Gogny parametrizations by modifying the density dependence of the symmetry energy predicted by the force in such a way that they can be applied to the neutron star domain and can also reproduce the properties of finite nuclei as good as their predecessors. These new parametrizations allow us to obtain stiffer EoS's based on the Gogny interactions, which predict maximum masses of neutron stars around two solar masses. Moreover, other global properties of the star, such as the moment of inertia and the tidal deformability, are in harmony with those obtained with other well tested EoSs based on the SLy4 Skyrme force or the Barcelona–Catania–Paris–Madrid (BCPM) energy density functional. Properties of the core-crust transition predicted by these Gogny EoSs are also analyzed. Using these new Gogny forces, the EoS in the inner crust is obtained with the Wigner–Seitz approximation in the Variational Wigner–Kirkwood approach along with the Strutinsky integral method, which allows one to estimate in a perturbative way the proton shell and pairing corrections. For the outer crust, the EoS is determined basically by the nuclear masses, which are taken from the experiments, wherever they are available, or by HFB calculations performed with these new forces if the experimental masses are not known. [ABSTRACT FROM AUTHOR]

Uranium is one of the strategic minerals used mainly in energetics. The main purpose of uranium mining is to achieve maximum production to meet the rapidly growing demand for energies. It needs to become aware that technological progress in mining processes could significantly reduce the negative impacts associated with environmental, economic, and social risks. Uranium mining is one of the most controversial topics. It is dealt with by many experts and scientists around the world. Various methods and technologies of uranium mining are encountered in professional journals, as well as political or socio-economic decisions based on the impact and importance of the energy potential of uranium deposits, or the environmental impacts of uranium mining. The deposit of Kuriskova is one of the most perspective deposits not only in Slovakia but also in the world. The deposit is located near the town of Kosice (with near 240,000 inhabitants) and near the recreational area of Jahodna in the east of the Slovak Republic. The analysis and determination of the energy potential of the deposit of Kuriskova shows that uranium reserves from this deposit would be able to fully cover the needs for nuclear power plants for the production of nuclear fuel, in the Slovak Republic, even in the longer term. With the above-mentioned energy potential of the deposit of Kuriskova at the level of 600 TWh, nuclear power plants in the Slovak Republic are able to be supplied with raw materials from the deposit of Kuriskova for about 40 years with the current amount of electricity produced (approx. 15 TWh). Therefore, for the purposes of this research, a proposal for the extraction of uranium reserves at the deposit of Kuriskova was made. Based on it, it is possible to determine the amount of recoverable uranium reserves from the deposit. A methodology has been determined with mining this proposal, which takes into account the basic criteria of uranium deposit mining, which was used for the selection of a suitable mining technology for the uranium deposit of Kuriskova. [ABSTRACT FROM AUTHOR]

We calculate neutron star masses and radii from equations of state based on recent high-quality chiral nucleon–nucleon potentials up to fifth order of the chiral expansion and the leading chiral three-nucleon force. Our focus is on the radius of a 1.4 M⊙ neutron star, for which we report predictions that are consistent with the most recent constraints. We also show the full M(R) relations up to their respective maximum masses. Beyond the densities for which microscopic predictions are derived from chiral forces, the equations of state are obtained via polytropic extrapolation. However, the radius of a 1.4 M⊙ neutron star is nearly insensitive to the high-density extrapolation. [ABSTRACT FROM AUTHOR]

We perform cooling simulations for isolated neutron stars using recently developed equations of state for their core. The equations of state are obtained from new parametrizations of the FSU2 relativistic mean-field functional that reproduce the properties of nuclear matter and finite nuclei, while fulfilling the restrictions on high-density matter deduced from heavy-ion collisions, measurements of massive 2 M⊙ neutron stars, and neutron star radii below 13 km. We find that two of the models studied, FSU2R (with nucleons) and in particular FSU2H (with nucleons and hyperons), show very good agreement with cooling observations, even without including extensive nucleon pairing. This suggests that the cooling observations are more compatible with an equation of state that produces a soft nuclear symmetry energy, hence it generates small neutron star radii. However, both models favor large stellar masses, above 1.8 M⊙, to explain the colder isolated neutron stars that have been observed, even if nucleon pairing is present. [ABSTRACT FROM AUTHOR]

Background: Women in deprived socioeconomic situations run a high pain risk. Although number of pain sites (NPS) is considered highly relevant in pain assessment, little is known regarding the relationship between socioeconomic conditions and NPS.Methods: The study population comprised 653 women; 160 recurrence-free long-term gynecological cancer survivors, and 493 women selected at random from the general population. Demographic characteristics and co-morbidity over the past 12 months were assessed. Socioeconomic conditions were measured by Socioeconomic Condition Index (SCI), comprising education, employment status, income, ability to pay bills, self-perceived health, and satisfaction with number of close friends. Main outcome measure NPS was recorded using a body outline diagram indicating where the respondents had experienced pain during the past week. Chi-square test and forward stepwise logistic regression were applied.Results and Conclusion: There were only minor differences in SCI scores between women with 0, 1-2 or 3 NPS. Four or more NPS was associated with younger age, higher BMI and low SCI. After adjustment for age, BMI and co-morbidity, we found a strong association between low SCI scores and four or more NPS, indicating that there is a threshold in the NPS count for when socioeconomic determinants are associated to NPS in women. [ABSTRACT FROM AUTHOR]