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The vibronic structure and nuclear dynamics in the first five excited singlet electronic states of bithiophene (2T) are investigated here. Specifically, considerations are given to comprehend the first two structureless and broad electronic absorption bands and the role of nonadiabatic coupling in the excited state relaxation mechanism of 2T in the gas phase. Associated potential energy surfaces (PESs) are established by constructing a model vibronic coupling Hamiltonian using 18 vibrational degrees of freedom and extensive ab initio electronic structure calculations. The topographies of these PESs are critically examined, and multiple conical intersections are established. The nuclear dynamics calculations are performed by propagating wave packets on the coupled electronic manifold. The present theoretical results are in good agreement with the experimental observations. It is found that strong nonadiabatic coupling between the S1–S4 and S1–S5 states along totally symmetric modes is predominantly responsible for the structureless and broad first absorption band, and overlapping S2, S3, S4, and S5 states form the second absorption band. Photorelaxation from the highly excited S5 to the lowest S1 state takes place through a cascade of diabatic population transfers among the S1–S4–S5 electronic manifold within the first ∼100 fs. Totally symmetric C=C stretching, C–S stretching, C–H wagging, ring puckering, and inter-ring bending modes collectively drive such relaxation dynamics. [ABSTRACT FROM AUTHOR]

The Random-Phase approximation (RPA) provides an appealing framework for semi-local density functional theory. In its Resolution-of-the-Identity (RI) approach, it is a very accurate and more cost-effective method than most other wavefunction-based correlation methods. For widespread applications, efficient implementations of nuclear gradients for structure optimizations and data sampling of machine learning approaches are required. We report a well scaling implementation of RI-RPA nuclear gradients on massively parallel computers. The approach is applied to two polymorphs of the benzene crystal obtaining very good cohesive and relative energies. Different correction and extrapolation schemes are investigated for further improvement of the results and estimations of error bars. [ABSTRACT FROM AUTHOR]

Note: Photoelectron imaging of MnO3- to probe its nuclear and electronic structure In this note, we revisit the MnO SB 3 sb SP - sp photoelectron spectrum using photoelectron imaging and reassess the assignment, showing that in fact, MnO SB 3 sb is planar in its ground electronic state. Using anion photoelectron spectroscopy, a previous study by Gutsev I et al. i [1] found the ground state of MnO SB 3 sb to have a trigonal pyramidal structure. A 126(22), 3495-3501 (2022). 10.1021/acs.jpca.2c02008 9 J. B. Kim, M. L. Weichman, and D. M. Neumark, "Structural isomers of Ti2O4 and Zr2O4 anions identified by slow photoelectron velocity-map imaging spectroscopy", J. Am. Chem. Soc. 136(19), 7159-7168 (2014). 10.1021/ja502713v 10 V. D. Moravec and C. C. Jarrold, "Study of the low-lying states of NiO- and NiO using anion photoelectron spectroscopy", J. Chem. Phys. [Extracted from the article]

The nuclear and magnetic structures of CaxSr2−xWMnO6 (x = 0.5, 1.0, 1.5) have been investigated by neutron diffraction at 295, 30 or 40 K, and 4 or 5 K. The compounds crystallized in the monoclinic symmetry with a space group P21/n. The nuclear structure consists of ordered WO6 and Mn2+O6 octahedral frameworks, with lattice constant a decreasing more rapidly than b with increasing Ca content. No structural change was found around the magnetic transition temperature, although the Mn octahedron below the magnetic order temperature exhibited a slightly compressed Jahn–Teller distortion (0.1–0.3 Å) along the c axis. A standard magnetic model was used to solve the magnetic structure, with the Mn magnetic moments ferromagnetically coupled along the a axis and anti-ferromagnetically coupled along the b and c axes, resulting in a magnetic propagation vector of k = (0,1/2, 1/2) and a magnetic superlattice of 1a × 2b × 2c. In each crystallographic cell, the Mn1–Mn2 atoms are antiferromagnetically configurated, compensating the total moment to zero by symmetry. A layer-type magnetism along the (111) crystallographic plane was confirmed to couple antiferromagnetically between these planes and ferromagnetically within them. The magnetic structure refinement confirmed an average Mn moment of 4.5 μB. Also, it reveals that the collinear magnetic Mn configuration has three possible spin orientations, namely, (with their standard deviation) [μx = (3.3 ± 0.4) μB, μy = (2.5 ± 0.3) μB, μz = (−0.7 ± 0.7) μB], [μx = (3.0 ± 0.4) μB, μy = (0.5 ± 0.2) μB, μz = (−2.8 ± 0.2) μB, and [μx = (−1.8 ± 0.4) μB, μy = (2.9 ± 0.2) μB, μz = (−2.4 ± 0.3) μB. The first configuration is estimated to be the ground state, while the other magnetic configurations are an optimum local value derived from the refinements. Combined with the density functional theory calculations, these experimental results confirm a high-spin state Mn2+ (d5) electron configuration. [ABSTRACT FROM AUTHOR]

Lamin A/C, essential inner nuclear membrane proteins, have been linked to progeria, a disease of accelerated aging, and many other diseases, which include cardiac disorder. Lamin A/C mutation and its phosphorylation are associated with altering nuclear shape and size. The role of lamin A/C in regulating normal cardiac function was reported earlier. In the present study, we hypothesized that Doxorubicin (Dox) may alter total lamin A/C expression and phosphorylation, thereby taking part in cardiac injury. An in vitro cellular injury model was generated with Dox (0.1–10.0 μM) treatment on cardiomyoblast cells (H9c2) to prove our hypothesis. Increased size and irregular (ameboid) nucleus shape were observed in H9c2 cells after Dox treatment. Similarly, we have observed a significant increase in cell death on increasing the Dox concentration. The expression of lamin A/C and its phosphorylation at serine 22 significantly decreased and increased, respectively in H9c2 cells and rat hearts after Dox exposure. Phosphorylation led to depolymerization of the lamin A/C in the inner nuclear membrane and was evidenced by their presence throughout the nucleoplasm as observed by immunocytochemistry techniques. Thinning and perforation on the walls of the nuclear membrane were observed in Dox-treated H9c2 cells. LMNA-overexpression in H9c2 protected the cells from Dox-induced cell death, reversing all changes described above. Further, improvement of lamin A/C levels was observed in Dox-treated H9c2 cells when treated with Purvalanol A, a CDK1 inhibitor and N-acetylcysteine, an antioxidant. The study provides new insight regarding Dox-induced cardiac injury with the involvement of lamin A/C and alteration of inner nuclear membrane structure. [Display omitted] • Doxorubicin induces phosphorylation of lamin A/C at serine 22 position. • Increased phosphorylation of lamin A/C leads depolymerization and loss of lamin A/C. • The Doxorubicin causes damage to the nuclear membrane structure. • The loss of lamin A/C and damage to nuclear membrane leads to cell viability loss. • LMNA-overexpression ceases the loss lamin A/C and alleviates nuclear membrane damage. [ABSTRACT FROM AUTHOR]

The pseudo-spin symmetry (PSS) provides an important angle to understand nuclear microscopic structure and the novel phenomena found in unstable nuclei. The relativistic Hartree–Fock (RHF) theory, that takes the important degrees of freedom associated with the π -meson and ρ -tensor (ρ -T) couplings into account, provides an appropriate description of the PSS restoration in realistic nuclei, particularly for the pseudo-spin (PS) doublets with high angular momenta ( l ˜ ). The investigations of the PSS within the RHF theory are recalled in this paper by focusing on the effects of the Fock terms. Aiming at common artificial shell closures appearing in previous relativistic mean-field calculations, the mechanism responsible for the PSS restoration of high- l ˜ orbits is stressed, revealing the manifestation of nuclear in-medium effects on the PSS, and thus, providing qualitative guidance on modeling the in-medium balance between nuclear attractions and repulsions. Moreover, the essential role played by the ρ -T coupling, that contributes mainly via the Fock terms, is introduced as combined with the relations between the PSS and various nuclear phenomena, including the shell structure and the evolution, novel halo and bubble-like phenomena, and the superheavy magicity. As the consequences of the nuclear force in complicated nuclear many-body systems, the PSS itself and the mechanism therein can not only deepen our understanding of nuclear microscopic structure and relevant phenomena, but also provide special insight into the nature of the nuclear force, which can further enrich our knowledge of nuclear physics. [ABSTRACT FROM AUTHOR]

Current practices for structural analysis of extremely large‐molecular‐weight polysaccharides via solution‐state nuclear magnetic resonance (NMR) spectroscopy incorporate partial depolymerization protocols that enable polysaccharide solubilization in suitable solvents. Non‐specific depolymerization techniques utilized for glycosidic bond cleavage, such as chemical degradation or ultrasonication, potentially generate structural fragments that can complicate complete and accurate characterization of polysaccharide structures. Utilization of appropriate enzymes for polysaccharide degradation, on the other hand, requires prior structural knowledge and optimal enzyme activity conditions that are not available to an analyst working with novel or unknown compounds. Herein, we describe an application of a permethylation strategy that allows the complete dissolution of intact polysaccharides for NMR structural characterization. This approach is utilized for NMR analysis of Xylella fastidiosa extracellular polysaccharide (EPS), which is essential for the virulence of the plant pathogen that affects multiple commercial crops and is responsible for multibillion dollar losses each year. [ABSTRACT FROM AUTHOR]

Disentangling the radio flux contribution from star formation (SF) and active-galactic-nuclei (AGNs) activity is a long-standing problem in extragalactic astronomy, since at frequencies of ≲ 10 GHz, both processes emit synchrotron radiation. We present in this work the general objectives of the PARADIGM (PAnchromatic high-Resolution Analysis of DIstant Galaxy Mergers) project, a multi-instrument concept to explore SF and mass assembly of galaxies. We introduce two novel general approaches for a detailed multiscale study of the radio emission in local (ultra) luminous infrared galaxies (U/LIRGs). In this work, we use archival interferometric data from the Very Large Array (VLA) centred at ∼ 6 GHz (C band) and present new observations from the e -Multi-Element Radio-Linked Interferometer Network (e -MERLIN) for UGC 5101, VV 705, VV 250, and UGC 8696. Using our image decomposition methods, we robustly disentangle the radio emission into distinct components by combining information from the two interferometric arrays. We use e -MERLIN as a probe of the core-compact radio emission (AGN or starburst) at ∼ 20 pc scales, and as a probe of nuclear diffuse emission, at scales ∼100–200 pc. With VLA, we characterize the source morphology and the flux density on scales from ∼200 pc up to and above 1 kpc. As a result, we find deconvolved and convolved sizes for nuclear regions from ∼10 to ∼200 pc. At larger scales, we find sizes of 1.5–2 kpc for diffuse structures (with effective sizes of ∼ 300–400 pc). We demonstrate that the radio emission from nuclear extended structures (∼ 100 pc) can dominate over core-compact components, providing a significant fraction of the total multiscale SF output. We establish a multiscale radio tracer for SF by combining information from different instruments. Consequently, this work sets a starting point to potentially correct for overestimations of AGN fractions and underestimates of SF activity. [ABSTRACT FROM AUTHOR]

This paper explores the empathic nuances of the therapeutic process with a person experiencing ongoing psychosis associated with a diagnosis of schizophrenia, and with a history of severe relational trauma. Incorporating the self psychological principles of working with the therapist's and client's forward edge, utilizing experience-near empathic attunement, and the somatic psychotherapy essential for kinaesthetic conversation were essential elements for the ongoing integration of the client's self. This work demonstrates the development of a nuanced understanding of pathological accommodation with its internal self-organizing dynamics as well as offering examples of forward edge movement. Interweaving vignettes from a two-year period with the subjective and intersubjective somatically animated experiencing of the therapist, the puzzle of how to work with all parts of the client unfolds gently and carefully. This paper outlines how connections were made between the two participants, in a clinical sense and within the client, creating a sense-making structure within the nuclear self experience of the client. Real life clinical experiences of what somatic psychotherapy, undertaken within a relational, intersubjective psychodynamic process, looks and feels like are in short supply. The presentation of this case hopes to remedy that by demonstrating the body mind integration required to work this way. [ABSTRACT FROM AUTHOR]

Experimental nuclear spectroscopic data are compiled and evaluated for 18 known nuclides of mass 165 (Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt). Detailed information is presented for each reaction and decay experiment. Combining all the available data, recommended values are provided for energies, spins and parities, and half-lives of levels, with energies, branching ratios and multipolarities of γ radiations, and characteristics of β and α radiations in radioactive decays. 165Dy, 165Ho, 165Er, 165Tm, 165Yb, 165Lu and 165Hf are among the most extensively studied nuclides via decay and high-spin gamma-ray spectroscopy measurements, followed by limited data for 165Tb, 165Ta, 165W, 165Re, and 165Os. No excited states have yet been identified in 165Sm, 165Gd, and 165Pt, while for 165Eu and 165Ir, information is available for only the g.s. and an isomer, but with no γ rays. This work supersedes earlier evaluation of A=165 nuclides by 2006Ja09. [ABSTRACT FROM AUTHOR]

The experimental nuclear spectroscopic data for known nuclides of mass number 76 (Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Kr, Rb, Sr, Y) have been evaluated and presented together with Adopted properties for levels and γ rays. With the exception of structure data for 76Ga nucleus, significant new data have been incorporated for all the other nuclides of A=76 since the previous 1995 update in ENSDF database and NDS publication 1995Si03. No data are yet available for excited states in 76Fe, 76Cu and 76Y. Decay scheme characteristics for the decay of 76Co, 76Ni, and 76Y are unknown while those for decays of 76Cu and 76Sr seem incomplete. For 76Ni, very little structure data are available, and for 76Ga and 76As, only low-spin (J < 4 or so) information is available. This work supersedes the data presented in the previous (1995Si03) NDS evaluation of A=76. [ABSTRACT FROM AUTHOR]

The cumulative and independent yields of various fission products within the mass range of 78 to 157 have been measured in the epi-cadmium neutron–induced fission of 238Pu by using an off-line γ-ray spectrometric technique. The lower yield of 136I than the usual trend indicates the formation of delayed neutron emitter 137I. From the cumulative yields, post-neutron mass chain yields were obtained by using the charge distribution correction. From the mass yield data, the peak-to-valley (P/V) ratio, the full-width at tenth-maximum of light and heavy mass wings, the average light mass and heavy mass as well as the average number of neutrons <ν> emitted were obtained. The mass chain yield data in the 238Pu(n,f) reaction were compared with similar data of the 238Pu(nth,f) reaction to examine the role of excitation energy on the nuclear structure effect and P/V ratio. [ABSTRACT FROM AUTHOR]

Exotic neutron-rich nuclei play an important role in r -process nucleosynthesis. We study the effect of including proper nuclear structure to calculate neutron capture and photodisintegration rates, especially for 19C and 20N, under the aegis of post-form distorted wave Born approximation (FRDWBA). Considering a network of neutron-rich C–N–O isotopes, we show the effect on abundance calculations in a neutrino-driven wind environment of a core-collapse supernova at two critical temperatures T 9 = 3.4 and 0.62. The results are compared for nuclear physics inputs sourced from the FRDWBA, statistical estimates, and standard databases. At temperatures T 9 = 3.4, where alpha capture, or at T 9 = 0.62, where the neutron capture dominates, one can distinguish the effect of accounting for the exotic nature of the nuclei involved. Furthermore, we assess the impact of varying neutron capture and photodisintegration rates involving halo or bubble structures on the abundances within the network. [ABSTRACT FROM AUTHOR]

In this article, we report the absolute production cross-section of 6.13, 6.92 and 7.12 MeV γ -rays from the 16O(p,p ′ γ )16O reaction for incident proton energy range of 8-16 MeV. Angular distributions of the three γ -rays have been measured for seven angles at 9 MeV proton energy. A detailed phenomenological optical model potential (OMP) was set up to analyse the cross-section data. The OMP parameters were optimised using elastic, polarization and total reaction data available in the literature for protons and neutrons. Low-lying states of 16O were coupled, the optical potential was deformed using deformation parameters, and several resonances were included in the calculations to account for the nuclear structure effects. The potentials so generated have been used to calculate the differential and total cross sections for both 16O(p,p ′ )16O and 16O(p,p ′ γ )16O reactions. Our calculated cross-sections are in fairly good agreement with our measured data for 6.13, 6.92 and 7.12 MeV γ -rays. However, there still exist discrepancies in reproduction of the finer details of the cross sections. The comparisons of the calculations with the data bring forth the rather complex roles of channel couplings, resonances in the p+16O system and target deformation in the variation of the cross sections with projectile energy. The increased contribution of nuclear structure effects in light mass nuclei, leads to an apparent loss of predictive power of the theoretical calculation, as we approach the low-energy region of less than 10 MeV projectile energy. [ABSTRACT FROM AUTHOR]

Linear-scaling techniques for Kohn–Sham density functional theory are essential to describe the ground state properties of extended systems. Still, these techniques often rely on the localization of the density matrix or accurate embedding approaches, limiting their applicability. In contrast, stochastic density functional theory (sDFT) achieves linear- and sub-linear scaling by statistically sampling the ground state density without relying on embedding or imposing localization. In return, ground state observables, such as the forces on the nuclei, fluctuate in sDFT, making optimizing the nuclear structure a highly non-trivial problem. In this work, we combine the most recent noise-reduction schemes for sDFT with stochastic optimization algorithms to perform structure optimization within sDFT. We compare the performance of the stochastic gradient descent approach and its variations (stochastic gradient descent with momentum) with stochastic optimization techniques that rely on the Hessian, such as the stochastic Broyden–Fletcher–Goldfarb–Shanno algorithm. We further provide a detailed assessment of the computational efficiency and its dependence on the optimization parameters of each method for determining the ground state structure of bulk silicon with varying supercell dimensions. [ABSTRACT FROM AUTHOR]

Pyrene fluorescence after a high-energy electronic excitation exhibits a prominent band shoulder not present after excitation at low energies. The standard assignment of this shoulder as a non-Kasha emission from the second-excited state (S2) has been recently questioned. To elucidate this issue, we simulated the fluorescence of pyrene using two different theoretical approaches based on vertical convolution and nonadiabatic dynamics with nuclear ensembles. To conduct the necessary nonadiabatic dynamics simulations with high-lying electronic states and deal with fluorescence timescales of about 100 ns of this large molecule, we developed new computational protocols. The results from both approaches confirm that the band shoulder is, in fact, due to S2 emission. We show that the non-Kasha behavior is a dynamic-equilibrium effect not caused by a metastable S2 minimum. However, it requires considerable vibrational energy, which can only be achieved in collisionless regimes after transitions into highly excited states. This strict condition explains why the S2 emission was not observed in some experiments. [ABSTRACT FROM AUTHOR]

It is important to understand whether α -clustering structures can leave traces in ultra-relativistic heavy ion collisions. Using the modified AMPT model, we simulate three α + core configurations of 44 Ti in 44 Ti + 44 Ti collisions at s NN = 5.02 TeV as well as other systems with Woods-Saxon structures. One of these configurations has no additional constraint, but the other two have the Mott density edge r Mott set as either a lower or upper bound on the cluster position r α to check the influence of α dissolution. This is the first time that the initial stage of the geometric properties in heavy-ion collisions has been configured using the traditional treatment of the nuclear structure. We compare the radial nucleon density, multiplicity distribution, transverse momentum spectra, eccentricity, triangularity, elliptic flow and triangular flow of these six systems. α + core structures can alter all these observations especially in the most-central collisions, among which elliptic flow is the most hopeful as a probe of such structures. [ABSTRACT FROM AUTHOR]

A detailed study of α -clusters decay is exhibited by incorporating crucial microscopic nuclear structure information into the estimations of half-life and preformation factor. For the first time, using the k-cross validation approach, two semi-empirical formulas for (1) α -decay half-life and (2) α -particle preformation factor, are picked out and subsequently modified by including shell, odd-nucleon blocking, and asymmetry effects along with the usual dependence on α -decay energy ( Q α ) and angular momentum of α -particle. Both the formulas are fitted for the two different regions separated by neutron number N = 126, as from the experimental systematics the role of N = 126 shell closure is found decisive in determining the trends of Q α , α -decay half-life, and α -particle preformation factor. It is found that the inclusion of the above-mentioned degrees of freedom significantly reduces the errors in the estimations when compared with several other similar modified/refitted semi-empirical relations indicating the robustness of the proposed formulas. The predictions of α -decay half-life throughout the periodic chart have been made including the unknown territory, future probable decay chain of self-conjugate nucleus 112 Ba terminated on 100 Sn, decay chain of 208 Pa through new isotope 204 Ac as well as decay chains of awaiting superheavy nuclei 298 Og and 299 120. This article is expected to provide a systematic approach to selecting the formula by which reliable predictions can be made. [ABSTRACT FROM AUTHOR]

We, the QUARTET Collaboration, propose an experiment to measure the nuclear charge radii of light elements with up to 20 times higher accuracy. These are essential both for understanding nuclear physics at low energies, and for experimental and theoretical applications in simple atomic systems. Such comparisons advance the understanding of bound-state quantum electrodynamics and are useful for searching for new physics beyond the Standard Model. The energy levels of muonic atoms are highly susceptible to nuclear structure, especially to the mean square charge radius. The radii of the lightest nuclei (with the atomic number, Z = 1 , 2 ) have been determined with high accuracy using laser spectroscopy in muonic atoms, while those of medium mass and above were determined using X-ray spectroscopy with semiconductor detectors. In this communication, we present a new experiment, aiming to obtain precision measurements of the radii of light nuclei 3 ≤ Z ≤ 10 using single-photon energy measurements with cryogenic microcalorimeters; a quantum-sensing technology capable of high efficiency with outstanding resolution for low-energy X-rays. [ABSTRACT FROM AUTHOR]

Simple Summary: Pampus is a genus of fish of commercial importance in Asia. This is a comprehensive study on the species delimitation and evolution history of Pampus species. This study integrated information on the skeletal structure and mitochondrial and nuclear molecular data of the genus Pampus to define their species delimitation. Based on these findings, we suggest that P. argenteus and P. echinogaster should be classified as the same species and P. liuorum is speculated to be a valid species. P. cinereus is closely related to P. minor, P. chinensis and P. punctatissimus, but these are different species. Pampus can be divided into six species: P. argenteus, P. punctatissimus, P. cinereus, P. chinensis, P. minor, and P. liuorum. The aim of this study was to resolve the controversies about the phylogeny and taxonomy of Pampus and provide a robust delimitation of Pampus for fisheries management. Pampus is a widespread species of fish in the western Pacific and Indian Oceans that has significant commercial worth. Its evolutionary history and phylogenetics are still poorly understood, and details on its intraspecific taxonomy are debatable, despite some morphological and molecular research. Here, we analyzed this species using skeletal structure data as well as nuclear (S7 gene) and mitochondrial genetic information (COI, D-loop and mitogenomes). We found that the genetic distance between P. argenteus and P. echinogaster was much smaller than that between other Pampus species, and both maximum likelihood and Bayesian phylogenetic trees yielded almost identical tree topologies. An additional and adjacent M repeat was found in the downstream region of the IQM gene cluster of P. argenteus and P. echinogaster, and the trnL2 gene of P. minor was translocated. The genus Pampus experienced early rapid radiation during the Palaeocene with major lineages diversifying within a relatively narrow timescale. Additionally, three different methods were conducted to distinguish the genus Pampus species, proving that P. argenteus and P. echinogaster are the same species, and P. liuorum is speculated to be a valid species. Overall, our study provides new insights not only into the evolutionary history of Pampus but its intraspecific taxonomy as well. [ABSTRACT FROM AUTHOR]

mRNA accessibility within messenger ribonucleoproteins (mRNPs), in contrast to DNA accessibility within chromatin, has not yet been well established as an important determinant of gene expression. Recent work has revealed the importance of the exon junction complex (EJC) as an architectural protein complex that controls mRNP packaging. An important function of EJC-mediated mRNP packaging is to regulate m6A specificity. Structures of nuclear mRNP globules reveal an architecture in which EJCs reside within the inaccessible interior of globules. mRNA exon architecture may be a determinant of mRNA accessibility due to EJC-mediated mRNP packaging. Gene expression is a complex process requiring many control mechanisms to achieve a desired phenotype. DNA accessibility within chromatin is well established as an important determinant of gene expression. By contrast, while mRNA also associates with a complement of proteins, the exact nature of messenger ribonucleoprotein (mRNP) packaging and its functional relevance is not as clear. Recent reports indicate that exon junction complex (EJC)-mediated mRNP packaging renders exon junction-proximal regions inaccessible for m6A methylation, and that EJCs reside within the inaccessible interior of globular transcription and export (TREX) complex-associated nuclear mRNPs. We propose that 'mRNA accessibility' within mRNPs is an important determinant of gene expression that may modulate the specificity of a broad array of regulatory processes including but not limited to m6A methylation. [ABSTRACT FROM AUTHOR]

The nuclear structure effects of correlated pairs of fission fragments in the mass distribution spectrum of the fissioning nucleus are investigated using the fragmentation theory based on the asymmetric two-centre shell model. The model is applied to explain the observed structure in relative mass distribution yields of even Z–even N correlated fission fragment pairs in the low-energy heavy-ion induced fusion–fission reactions 208 Pb (18 O,f) and 238 U (18 O,f). In each of these reactions, the respective fused system is considered to utilise its excitation energy in 0–14 neutron evaporation channels before proceeding to decay. The fissioning isotopes ( 226 - 212 Th and 256 - 242 Fm) resulted after neutron evaporation (in the step of Δ n = 2 ) contribute to the observed even–even individual fission fragments mass distribution spectra. It is shown that the most probable decay channel consisting of correlated pair of magic and deformed shell fission fragments always has a larger mass distribution yield than that containing both magic shell structure fission fragments. The pear-shaped structure that emerges from the combined magic plus deformed shell fission fragments might have relevance to an occurrence of stable octupole deformation of a fissioning nucleus before saddle configuration, which was first noticed by Johansson (S A E Johansson, Nucl. Phys. 22 , 529 (1961)) and more recently, authenticated by Scamps and Simenel (G Scamps and C Simenel, Nature 564 , 382 (2018)). Thus, the combined quantum shell effects of magic and deformed fission fragments both in potential and the cranking mass parameters decide the most probable decay modes (i.e., the correlated pairs of fission fragments with maximum yields) in fusion–fission reactions ( 208 Pb (18 O,f) and 238 U (18 O,f)). [ABSTRACT FROM AUTHOR]

The magnetic dipole moment and the electric quadrupole moment are the nuclear moments that provide us with key information about the proton and neutron configurations in a nucleus and the shape of a nucleus, respectively. In the study of nuclear structure through the measurement of the nuclear moments, a technique to produce spin orientation of rare-isotope beams has played important roles. Recently, a scheme of the two-step projectile fragmentation was developed to produce high spin alignment in RI beams and was applied to the frontier of the study for nuclear structure of neutron-rich nuclei, such as 75 Cu and 99 Zr. The recent activities of the nuclear-moment measurements using highly spin-aligned beams at RIKEN RIBF are reported. [ABSTRACT FROM AUTHOR]

The nuclear lamina (NL) plays various roles and participates in nuclear integrity, chromatin organization, and transcriptional regulation. Lamin proteins, the main components of the NL, form a homogeneous meshwork structure under the nuclear envelope. Lamins are essential, but it is unknown whether their homogeneous distribution is important for nuclear function. Here, we found that PIGB, an enzyme involved in glycosylphosphatidylinositol (GPI) synthesis, is responsible for the homogeneous lamin meshwork in Drosophila. Loss of PIGB resulted in heterogeneous distributions of B-type lamin and laminbinding proteins in larval muscles. These phenotypes were rescued by expression of PIGB lacking GPI synthesis activity. The PIGB mutant exhibited changes in lamina-associated domains that are large heterochromatic genomic regions in the NL, reduction of nuclear stiffness, and deformation of muscle fibers. These results suggest that PIGB maintains the homogeneous meshwork of the NL, which may be essential for chromatin distribution and nuclear mechanical properties. [ABSTRACT FROM AUTHOR]

The study of neutron-rich nuclei's form factors, root-mean-square radius (rms), and nuclear density distributions is the focus of this work for the nuclei (22N, 23 O and 24F). With the use of a strong short-range effect and a strong tensor force, the nucleons distribution function of the two oscillating harmonic particles in a two-frequency shell model operates with two different parameters: the first (bcore), for the inner (core) orbits, and the second (bvalence) for the outer (halo) orbits. This work demonstrated the existence of neutron halo nuclei for the nuclei (22N, 23O and ²4F) in the (2s1/2) shell. The computed density distribution of neutron, proton and matter for these nuclei displayed the long tail performance. Using the Borne approximation of the plane wave, the elastic form factor of the electron scattering from the alien nucleus was calculated, this form factor is independent of the neutrons that make up the halo, but rather it results from a difference in the proton density distribution of the last proton in the nuclei. Fortran 95 power station program was used to the neutron, proton and matter density, elastic electron scattering form factor, and rms radii. The calculated outcomes for these exotic nuclei were in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The mean transverse momentum of produced particles, [ p T ] , and its event-by-event fluctuations give direct access to the initial conditions of ultra-relativistic heavy-ion collisions and help probe the colliding nuclei's structure. The [ p T ] fluctuations can be studied via multi-particle p T correlations; so far, only the lowest four orders have been studied. Higher-order fluctuations can provide stronger constraints on the initial conditions and improved sensitivity to the detailed nuclear structure; however, their direct implementation can be challenging and is still lacking. In this paper, we apply a generic recursive algorithm for the genuine multi-particle p T correlations, which enables the accurate study of higher-order [ p T ] fluctuations without heavy computational cost for the first time. With this algorithm, we will examine the power of multi-particle p T correlations through Monte Carlo model studies with different nuclear structures. The impact on the nuclear structure studies, including the nuclear deformation and triaxial structure, will be discussed. These results demonstrate the usefulness of multi-particle p T correlations for studying nuclear structure in high-energy nuclei collisions at RHIC and the LHC, which could serve as a complementary tool to existing low-energy nuclear structure studies. [ABSTRACT FROM AUTHOR]

Background: The bacterium Staphylococcus aureus has stood out for presenting a high adaptability, acquiring resistance to multiple drugs. The search for natural or synthetic compounds with antibacterial properties capable of reversing the resistance of S. aureus is the main challenge to be overcome today. Natural products such as chalcones are substances present in the secondary metabolism of plants, presenting important biological activities such as antitumor, antidiabetic, and antimicrobial activity. Objectives: In this context, the aim of this work was to synthesize the chalcone (2E)‐1‐(3'‐aminophenyl)‐3‐(4‐dimethylaminophenyl)‐prop‐2‐en‐1‐one with nomenclature CMADMA, confirm its structure by nuclear magnetic resonance (NMR), and evaluate its antibacterial properties. Methods: The synthesis methodology used was that of Claisen‐Schmidt, and spectroscopic characterization was performed by NMR. For microbiological assays, the broth microdilution methodology was adopted in order to analyze the antibacterial potential of chalcones and to analyze their ability to act as a possible inhibitor of β‐lactamase and efflux pump resistance mechanisms, present in S. aureus strain K4100. Results: The results obtained show that CMADMA does not show direct antibacterial activity, expressing a MIC of ≥1024 μg/mL, or on the enzymatic mechanism of β‐lactamase; however, when associated with ethidium bromide in efflux pump inhibition assays, CMADMA showed promising activity by reducing the MIC of the bromide from 64 to 32 μg/mL. Conclusion: We conclude that the chalcone synthesized in this study is a promising substance to combat bacterial resistance, possibly acting in the inhibition of the QacC efflux pump present in S. aureus strain K4100, as evidenced by the reduction in the MIC of ethidium bromide. [ABSTRACT FROM AUTHOR]

The LINC complex transmits cytoskeletal forces into the nucleus to control the structure and movement of nuclear contents. It is formed of nuclear SUN and cytoplasmic KASH proteins, which interact within the nuclear lumen, immediately below the outer nuclear membrane. However, the symmetrical location of KASH molecules within SUN-KASH complexes in previous crystal structures has been difficult to reconcile with the steric requirements for insertion of their immediately upstream transmembrane helices into the outer nuclear membrane. Here, we report the crystal structure of the SUN-KASH complex between SUN1 and JAW1/LRMP (KASH6) in an asymmetric 9:6 configuration. This intertwined assembly involves two distinct KASH conformations such that all six KASH molecules emerge on the same molecular surface. Hence, they are ideally positioned for insertion of upstream sequences into the outer nuclear membrane. Thus, we report a SUN-KASH complex architecture that appears to be directly compatible with its biological role. The X-ray crystal structure of a SUN1-KASH6 complex reveals an asymmetric trimer-of-trimers LINC complex architecture that fulfils the steric requirements for its biological role in transmitting cytoskeletal forces across the nuclear envelope. [ABSTRACT FROM AUTHOR]

Recent measurement of the parity-violating (PV) asymmetry in the elastic electron scattering on 2 7 Al target evokes the interest in the distribution of the neutron in the nucleus. In this work, we calculate the neutron skin thickness ( R n p ) of 2 7 Al with nonrelativistic nuclear structure models. We focus on the role of the effective mass, symmetry energy and pairing force. Models are selected to have effective masses in the range (0.58–1.05) M where M is the nucleon mass in free space, and stiffness of the symmetry energy is varied by choosing the slope of the symmetry energy in the range 9.4–100.5 MeV. Effect of pairing force is investigated by calculating nuclear properties with and without pairing. With constant force pairing, we obtain R n p = 0. 0 0 1 –0.013 fm. The result is independent of the effective mass and symmetry energy. However, R n p is negative when the pairing force is switched off, so the pairing force plays an essential role to make R n p positive and constrained in a narrow range. We also calculate the PV asymmetry ( A pv ) in the elastic electron- 2 7 Al scattering in the Born approximation at the kinematics of the Qweak experiment. We obtain a very narrow-ranged result A pv = (2. 0 7 − 2. 0 9) × 1 0 − 6 . The result is consistent with the experiment and insensitive to the effective mass and symmetry energy. [ABSTRACT FROM AUTHOR]

The cluster radioactivity of 2 2 2 , 2 2 4 , 2 2 6 Ra, 2 2 3 , 2 2 5 Ac, 2 3 2 , 2 3 4 , 2 3 5 , 2 3 6 U, 2 3 6 , 2 3 8 Pu, 2 3 4 , 2 3 6 U, 2 3 2 , 2 3 3 , 2 3 4 , 2 3 5 , 2 3 6 U and 2 3 0 , 2 3 2 Th isotopes which emitted 1 4 C, 2 4 Ne, 2 8 Mg, 2 6 Ne, 2 8 Mg, 2 4 Ne, respectively, has been analyzed with the help of fractional calculus for investigating the connection between order of the fractional derivative and nuclear structure. When the neutron number of daughter nuclei is equal to magic number, order of the fractional derivative shows a maximum. It is shown that there is a relationship between the order of fractional derivative and shell effect. This order has a similar role to the preformation factor in cluster radioactivity. [ABSTRACT FROM AUTHOR]

High-resolution laser spectroscopy can be used to precisely measure atomic hyperfine structures and shifts in spectral lines. These nuclear perturbations of the atomic structure provide insight into the bulk properties of nuclei as well as the intricate details of the nucleon–nucleon interactions inside the atomic nucleus. Collinear laser spectroscopy in particular allows for the extraction of nuclear moments and changes in the mean-square charge radii with high precision. We provide an overview of the manner in which collinear laser spectroscopy is currently implemented at radioactive ion beam facilities. Through examples, we illustrate how this method gives access to direct and nuclear model-independent evidence for changes in nuclear spins, electromagnetic moments and nuclear radii caused by structural changes in atomic nuclei. [ABSTRACT FROM AUTHOR]

High performance computing (HPC) applications that work with redundant sequences of data can benefit from their deduplication. We study this problem on the symmetry-adapted no-core shell model (SA-NCSM), where redundant sequences of different kinds naturally emerge in the data of the basis of the Hilbert space physically relevant to a modeled nucleus. For a fast solution of this problem on multicore architectures, we propose and present three multithreaded algorithms, which employ either concurrent hash tables or parallel sorting methods. Furthermore, we present evaluation and comparison of these algorithms based on experiments performed with real-world SA-NCSM calculations. The results indicate that the fastest option is to use a concurrent hash table, provided that it supports sequences of data as a type of table keys. If such a hash table is not available, the algorithm based on parallel sorting is a viable alternative. [ABSTRACT FROM AUTHOR]

Cytoplasmic Dynein is a multiple-subunit macromolecular motor protein involved in the transport process of cells. The Dynein intermediate chain (DIC) is one of the subunits of Dynein-1. In our previous studies, we showed that Pt-DIC may play an important role in the nuclear deformation of spermiogenesis in Portunus trituberculatus. Lamin B is essential for maintaining nuclear structure and functions. Surprisingly, Pt-Lamin B was expressed not only in the perinucleus but also in the pro-acrosome during spermiogenesis in P. trituberculatus. Studies have also shown that Dynein-1 can mediate the transport of Lamin B in mammals. Thus, to study the relationship of Pt-DIC and Pt-Lamin B in the spermatogenesis of P. trituberculatus, we knocked down the Pt-DIC gene in P. trituberculatus by RNAi. The results showed that the distribution of Pt-DIC and Pt-Lamin B in spermiogenesis was abnormal, and the colocalization was weakened. Moreover, we verified the interaction of Pt-DIC and Pt-Lamin B via coimmunoprecipitation. Therefore, our results suggested that both Pt-DIC and Pt-Lamin B were involved in the spermatogenesis of P. trituberculatus, and one of the functions of Dynein-1 is to mediate the transport of Lamin B in the spermiogenesis of P. trituberculatus. [ABSTRACT FROM AUTHOR]

In eukaryotic cells, RNAs transcribed by RNA polymerase-II receive the modification at the 5′ end. This structure is called the cap structure. The cap structure has a fundamental role for translation initiation by recruiting eukaryotic translation initiation factor 4F (eIF4F). The other important mediator of the cap structure is a nuclear cap-binding protein complex (CBC). CBC consists of two proteins, which are renamed as NCBP1 and NCBP2 (previously called as CBP80/NCBP and CBP20/NIP1, respectively). This review article discusses the multiple roles CBC mediates and co-ordinates in several gene expression steps in eukaryotes. [ABSTRACT FROM AUTHOR]

The nearby dwarf galaxy POX 52 at z = 0.021 hosts an active galactic nucleus (AGN) with a black hole (BH) mass of M BH ∼ 105–6 M ⊙ and an Eddington ratio of ∼0.1–1. This object provides the rare opportunity to study both AGN and host-galaxy properties in a low-mass highly accreting system. To do so, we collected its multiwavelength data from X-ray to radio. First, we construct a spectral energy distribution, and by fitting it with AGN and host-galaxy components, we constrain AGN-disk and dust-torus components. Then, while considering the AGN-disk emission, we decompose optical Hubble Space Telescope images. As a result, it is found that a classical bulge component is probably present, and its mass (M bulge) is consistent with an expected value from a local relation. Lastly, we analyze new quasi-simultaneous X-ray (0.2–30 keV) data obtained by the Nuclear Spectroscopic Telescope Array and XMM-Newton. The X-ray spectrum can be reproduced by multicolor blackbody, warm and hot coronae, and disk and torus reflection components. Based on this, the spin is estimated to be a spin = 0.998−0.814, which could suggest that most of the current BH mass was achieved by prolonged mass accretion. Given the presence of the bulge, POX 52 would have undergone a galaxy merger, while the M BH– M bulge relation and the inferred prolonged accretion could suggest that AGN feedback occurred. Regarding the AGN structure, the spectral slope of the hot corona, its relative strength to the bolometric emission, and the torus structure are found to be consistent with Eddington-ratio dependencies found for nearby AGNs. [ABSTRACT FROM AUTHOR]

The advances in technology mainly concerning ion traps, storage rings, lasers, high-precision frequency measurements, detectors, and particle beams as well as advances in atom and ion manipulation have allowed for a considerable progress in the determination of fundamental parameters and quantities of radionuclides such as masses, electromagnetic moments, lifetimes and beta decay correlations. The main subjects covered by this topical collection are: high-precision mass measurements both with Penning traps and storage rings for neutrino physics, nuclear structure, astrophysics, and decay studies. Laser spectroscopy is applied for the determination of other ground state properties like spins, moments, and nuclear charge radii. Furthermore, results from decay studies of highly charged ions and reactions in storage rings are presented. [ABSTRACT FROM AUTHOR]

The limited amount of economically suitable natural uranium resources forces us to improve the existing structure of the nuclear power system and its fuel cycle. With the current natural uranium reserves, it becomes practically impossible to significantly increase nuclear power plant (NPP) capacities in the existing system on the basis of thermal reactors operating in the open nuclear fuel cycle (ONFC). In order to solve this problem, the article considers the introduction of fusion-fission reactors (FFRs). FFR blankets produce 233U, which is further utilized in thermal reactors. In this article, fuel compositions of VVER-1200 reactors with the addition of 233U and thorium are studied, which make it possible to reduce the consumption of natural uranium and/or utilize already available raw materials in the form of depleted and regenerated uranium. On the basis of the scenario of the Russian nuclear power system (NPS) development within the ONFC with VVER-1200 reactors, the required 233U production volumes and the corresponding FFR fraction are determined for all fuel options. The risks of thorium introduction into the nuclear fuel cycle (NFC) are reviewed. [ABSTRACT FROM AUTHOR]

Since Mayer and Jensen employed the single-particle shell model to interpret the magic numbers, various microscopic nuclear models have been developed to study the nuclear force and structure. The configuration–interaction shell model (CISM), performed in truncated model space with the inclusion of the residual interaction, is one widely-used nuclear structure model. In the last decade, CISM has progressed in investigating the cross-shell excitation in exotic light nuclei, the similarity and difference in mirror nuclei, and the isomerism and seniority conservation in medium and heavy nuclei. Additionally, researchers have attempted to construct effective Hamiltonians for nuclei near 1 3 2 Sn and 2 0 8 Pb through a unified way in the CISM framework. In parallel, related models, including the nucleon-pair approximation (NPA) approach, the Monte Carlo shell model (MCSM), the projected shell model (PSM), the Gamow shell model (GSM), etc., have also been extensively developed and validated in the last decade. This paper reviews the recent progress in CISM and some related models. [ABSTRACT FROM AUTHOR]

The structure of nuclear matter at short internucleon distances is one of the poorly studied aspects of nuclear physics. At distances of the order of the nucleon radius, nuclear matter is represented by the pairs of correlated nucleons with relative momenta exceeding the Fermi momenta that emerge for a short time. Such structures, whose local density is comparable to the density of neutron stars, arise from fluctuations in the average nuclear density. One of the important characteristics of nucleon–nucleon correlations is their universality implying the independence of their properties from the nuclear mass number. Therefore, the peculiarities of these objects of nuclear structure reflect the properties of nuclear matter rather than specific nuclei. Information about the short-distance physics is extracted from the analysis of processes with high energy–momentum transfers. Until now, the property of universality has been observed in electron–nucleus collisions only for the breakup of nucleon pairs. In this paper we analyze the data on the cumulative production of pions by protons on a set of nuclear targets and for the first time have established the existence of universality of two-nucleon correlations in the production of π+ and π– mesons. We have obtained evidence for the involvement of three-nucleon correlations in the production of pions beyond the kinematics of their production in interactions with two-nucleon objects. [ABSTRACT FROM AUTHOR]

The low-lying nuclear structure of even-even Zn isotopes ranging from 62 Zn to 70 Zn has been comprehensively examined through large scale shell model calculations. These calculations encompassed the f 5 / 2 p 3 / 2 , 1 / 2 g 9 / 2 (fpg) model space without any truncation, employing 56 Ni as an inert core. Two different effective interactions, JUN45 and jj44b, were utilized in these calculations. Various critical observables, including excitation energies, reduced transition strengths, and electric quadrupole moments, were computed and then evaluated in the context of existing experimental data. The configurations of the resulting wave functions were also thoroughly analyzed. Furthermore, occupation probabilities for distinct single-particle orbitals were determined, with particular attention given to the pivotal role of the g 9 / 2 orbital in elucidating the nuclear structure of heavy Zn isotopes. Additionally, rotational invariants were calculated for the ground state, shedding light on a prolate deformation in 62 Zn and 64 Zn, while suggesting moderate prolate-triaxial excitations in 66 Zn, 68 Zn, and 70 Zn. These findings hold significant relevance for interpreting the intriguing outcomes of sub-barrier Coulomb excitation experiments, offering invaluable insights into the static electromagnetic properties of the nucleus through a model-independent approach. [ABSTRACT FROM AUTHOR]

The genera Carolibrandtia and Chlorella have been described as small green algae with spherical cell shapes that inhabit various environments. Species of these genera are often difficult to identify because of their simple morphology and high phenotypic plasticity. We investigated two small coccoid strains from Antarctica based on morphology, molecular phylogeny by two alignment methods which have been applied to previous phylogenetic studies of the genus Chlorella, and comparison of the secondary structures of nuclear small subunit (SSU) and internal transcribed spacer (ITS) rDNA sequences. Light microscopy of two strains revealed spherical cells containing chloroplasts with pyrenoids, and the morphological characteristics of the strains were nearly identical to those of other Chlorella species. However, based on the phylogenetic analyses of nuclear SSU and ITS rDNA sequences, it was determined that the Antarctic microalgal strains belonged to two genera, as the Chlorella and Carolibrandtia. In addition, the secondary structures of the SSU and ITS2 sequences were analyzed to detect compensatory base changes (CBCs) that were used to identify and describe the two strains. A unique CBC in the SSU rDNA gene was decisive for distinguishing strain CCAP 211/45. The ITS2 rDNA sequences for each strain were compared to those obtained previously from other closely related species. Following the comparison of morphological and molecular characteristics, we propose KSF0092 as a new species, Chlorella terrestris sp. nov., and the reassignment of the strain Chlorella antarctica CCAP 211/45 into Carolibrandtia antarctica comb. nov. [ABSTRACT FROM AUTHOR]