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The Jost function formalism is extended with use of the complex potential in this paper. We derive the Jost function by taking into account the dual state which is defined by the complex conjugate the complex Hamiltonian. By using the unitarity of the S-matrix which is defined by the Jost function, the optical theorem with the complex potential is also derived. The role of the imaginary part of the complex potential for both the bound states and the scattering states is figured out. The numerical calculation is performed by using the complex Woods-Saxon potential, and some numerical results are demonstrated to confirmed the properties of extended Jost function formalism.

Research into the cosmic synthesis of the elements, the evolution and explosion of stars, the nature of the early Universe, and other important topics in nuclear astrophysics are at the forefront of nuclear science. These studies are motivating laboratory measurements and theoretical calculations that, after significant investments, are pushing the boundaries of what is possible. The latest nuclear results, however, must be specially prepared before they can be used to advance our knowledge of the cosmos. This processing requires a set of resources unique to nuclear astrophysics, and an impressive collection of nuclear reaction and nuclear structure datasets, processing codes, thermonuclear reaction rate libraries, and simulation codes and services have been developed for the field. There are, however, some serious challenges to these efforts that will only worsen in the future, making it important to develop strategies and act now to ensure a sustainable future for this work. After detailing the specific data types needed for nuclear astrophysics and the available data resources, the major challenges in this work and their implications are discussed. A set of initiatives are proposed to meet those challenges along with suggested implementations and possible ways that they may advance our understanding of the Universe and strengthen the field of nuclear astrophysics.

Single molecule localization microscopy offers resolution nearly down to the molecular level with specific molecular labelling, and is thereby a promising tool for structural biology. In practice, however, the actual value to this field is limited primarily by incomplete fluorescent labelling of the structure. This missing information can be completed by merging information from many structurally identical particles in a particle fusion approach similar to cryo-EM single-particle analysis. In this paper, we present a data analysis of particle fusion results of fluorescently labelled Nup96 nucleoporins in the Nuclear Pore Complex to show that Nup96 occurs in a spatial arrangement of two rings of 8 units with two Nup96 copies per unit giving a total of 32 Nup96 copies per pore. We use Artificial Intelligence assisted modeling in Alphafold to extend the existing cryo-EM model of Nup96 to accurately pinpoint the positions of the fluorescent labels and show the accuracy of the match between fluorescent and cryo-EM data to be better than 3 nm in-plane and 5 nm out-of-plane. [ABSTRACT FROM AUTHOR]

In view of nuclear structure calculations, the second Pöschl–Teller potential is parameterized to study nucleon–nucleon and nucleon–nucleus elastic scattering. By exploiting the variable phase approach to potential scattering, phase parameters, cross sections, analyzing powers, etc., are computed and compared with earlier works. The calculated cross sections agree with the experiments below 25 MeV within the error bars for the (n-p) and (n-d) systems. [ABSTRACT FROM AUTHOR]

Chemical modifications of nucleotides expand the complexity and functional properties of genomes and transcriptomes. A handful of modifications in DNA bases are part of the epigenome, wherein DNA methylation regulates chromatin structure, transcription, and co-transcriptional RNA processing. In contrast, more than 150 chemical modifications of RNA constitute the epitranscriptome. Ribonucleoside modifications comprise a diverse repertoire of chemical groups, including methylation, acetylation, deamination, isomerization, and oxidation. Such RNA modifications regulate all steps of RNA metabolism, including folding, processing, stability, transport, translation, and RNA's intermolecular interactions. Initially thought to influence all aspects of the post-transcriptional regulation of gene expression exclusively, recent findings uncovered a crosstalk between the epitranscriptome and the epigenome. In other words, RNA modifications feedback to the epigenome to transcriptionally regulate gene expression. The epitranscriptome achieves this feat by directly or indirectly affecting chromatin structure and nuclear organization. This review highlights how chemical modifications in chromatin-associated RNAs (caRNAs) and messenger RNAs (mRNAs) encoding factors involved in transcription, chromatin structure, histone modifications, and nuclear organization affect gene expression transcriptionally. [ABSTRACT FROM AUTHOR]

We describe connections between shell-model calculation results and predictions for two-nucleon transfer reactions. Measurements of the 30 Mg(t,p) 32 Mg reaction were used to identify a low-lying shape-coexisting 0 + state in 32 Mg. Interpretations of those early, limited data were based on simple empirical models. The cross sections for two-nucleon transfer are, however, extremely sensitive to the details of the nuclear-structure. Motivated by the possibility of new high-resolution two-nucleon transfer measurements around the N = 20 Island of Inversion, we have performed shell-model calculations wave functions for states in the nuclei 30 , 32 Mg using the SDPF-M and SDPF-MU interactions, and from those calculations obtain the two-nucleon transfer amplitudes that we use to predict cross sections for the 28 , 30 Mg(t,p) 30 , 32 Mg reactions. The combined results show how the nuclear structure properties influence experimental observables for the (t,p) reaction. We compare our results with the existing data. [ABSTRACT FROM AUTHOR]

Copyright of Perspektiven der Wirtschaftspolitik is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The term single is limited as it is defined as the absence of a romantic partner, which places one's relationship status within a binary, assumes availability for romantic partnership, and implies single is a transitory state preceding union formation. These perceptions of singlehood serve to maintain hegemonic structures of marriage and nuclear family. However, the implications associated with the term single do not represent the experiences of all singles. This paper proposes an alternative framework for classifying singles based on their approach to romantic relationships that considers both openness to and desire for romantic partnership. I provide a typology of singles that defy the assumptions of singlehood and situate these categories within my theoretical framework. Finally, I demonstrate how this framework highlights the potential stability of singlehood, and I conclude by examining how social scientists can use this theory to better understand heterogeneity in singles' experiences. [ABSTRACT FROM AUTHOR]

The shape and internal structure of an atomic nucleus can change significantly with increasing excitation energy, angular momentum, or isospin asymmetry. As an example of this structural evolution, linear-chain configurations in carbon or heavier isotopes have been predicted for decades. Recent studies have found non-stability of this structure in 12C while evidenced its appearance in 16C. It is then necessary to investigate the linear-chain molecular structures in 14C to clarify the exact location on the nuclear chart where this structure begins to emerge, and thus to benchmark theoretical models. Here we show a cluster-decay experiment for 14C with all final particles coincidentally detected, allowing a high Q-value resolution, and thus a clear decay-path selection. Unambiguous spin-parity analyses are conducted, strongly evidencing the emergence of the π-bond linear-chain molecular rotational band in 14C. The present results encourage further studies on even longer chain configurations in heavier neutron-rich nuclei. The existence of linear-chain configurations in light nuclei has been predicted for decades, but the finding of the exact location on the nuclear chart where this exotic structure emerges has proven to be challenging experimentally. Here, the authors performed an inelastic excitation and cluster-decay experiment followed by unambiguous spin-parity analyses and provide evidence for the emergence of the nuclear chain structure starting from 14C. [ABSTRACT FROM AUTHOR]

Experimental nuclear spectroscopic data are evaluated for 12 known nuclides of mass number A=44 (Si, P, S, Cl, Ar, K, Ca, Sc, Ti, V, Cr, Mn). Detailed evaluated information are presented for each reaction and decay. Recommended values combining all available data are provided for all spectroscopic properties of each level, γ -ray, and decay radiation. No excited states have yet been identified in 44Si, 44P, 44Cr, and 44Mn. Information for excited states in 44Cl and 44V are limited. Nuclides of 44S, 44Ar and 44K have been studied via only a few reactions and decays, while 44Ca, 44Sc and 44Ti are the most investigated nuclides through various reactions and decays. Evaluators note that the half-life of the g.s. of 44S has been measured independently, with fairly good statistics, in three references, most precise being 100 ms 1 by 2004Gr20, but this value is in disagreement with the values of 125.5 ms 25 and 119 ms 6 by 2022Tr03, and 123 ms 10 by 1995So03. We adopted the unweighted average of this discrepant dataset. Another outstanding issue is that of the β +-delayed proton decay of 44Cr g.s. to 44V, where the T=2, 0+ IAS state in 44V is expected to be strongly populated by a superallowed β transition, but has not been definitely identified as discussed in detail by 2020Fu05. A detailed study of 44Cr decay is required to unravel the status of the T=2, 0+ IAS state in 44V. This work supersedes earlier ENSDF evaluations of A=44 by 2011Ch39 and 1999Ca45. [ABSTRACT FROM AUTHOR]

The normal deformed bands of 1 6 7 , 1 6 9 , 1 7 1 Lu isotopes have been studied by using projected shell model approach. The band head spins, configurations and energies of all the normal deformed bands are reproduced well by the above said approach. The present calculations have predicted I = 7 ∕ 2 − band head spin for [523]7/2− bands of 1 6 9 , 1 7 1 Lu. The observed systematics of aligned angular momenta and the experimental differences in frequencies around the backbends for all the normal deformed bands are reproduced well by the theoretical results. Besides this, the observed backbends or upbends in these isotopes may be ascribed to the alignment of a pair of neutrons in the neutron 1 i 1 3 ∕ 2 orbital. Although the theoretical B (E 2) values obtained from the projected shell model wavefunctions overestimate the experimental B (E 2) values in 1 6 7 Lu, yet they are close to the measured values, considering the precision of measurement. The reduction in the theoretical B (E 2) values around the band crossing region may be ascribed to change in nuclear structure of yrast bands due to neutron pair alignment in 1 i 1 3 ∕ 2 orbital. [ABSTRACT FROM AUTHOR]

The detailed study of radioactive nuclei has resulted in opportunities for addressing many open questions in low-energy nuclear physics. For over three decades, the TwinSol separator at the University of Notre Dame has produced high-quality in-flight radioactive beams at low-energy for light isotopes that have been used in experiments aimed at nuclear structure, astrophysics, and fundamental symmetries studies. We have recently upgraded the TwinSol separator by adding additional elements: a dipole magnet, and a third solenoid. This new TriSol separator will improve the quality and purity of future radioactive beams. This improvement will enable the use of heavier beams and address beam contamination that has hindered past experiments. The current status of TriSol and its science program will be presented along with the role the TriSol program plays in the current landscape of nuclear physics user facilities. The TriSol program includes plans for studies of 11C(p , p)11C reaction for investigating the nature of the first stars, 14O(α , p)17F and its influence on reaction networks in X-ray bursts, the measurement of fusion reactions on Ne isotopes important for pycnonuclear reactions, precision half-life measurements for fundamental symmetries studies, and the use of TriSol as a magnetic spectrometer. [ABSTRACT FROM AUTHOR]

We report on the development, characterization, and first application of a specialized resonance ionization laser ion source for high-resolution spectroscopy applications below usual hot cavity Doppler broadening limitations, for on-line experiments at CERN-ISOLDE. The new PI-LIST ion source comprises perpendicular laser/atom beam interaction in a radio-frequency quadrupole unit directly downstream the hot atomizer cavity. A spectral linewidth of 200–300 MHz is demonstrated, with the potential to achieve below 100 MHz. Compared to standard in-source laser ionization, the efficiency reduction factor ranges from a few 100 to above 1000. The implementation of this ion source concept at thick target radioactive ion beam facilities will greatly enhance capabilities for nuclear structure investigations without demanding dedicated experimental beam line setups, and will facilitate the delivery of isomer-pure beams to experimental stations. [ABSTRACT FROM AUTHOR]

The nuclear structure for some selected Si isotopes has been studied using a truncated large-scale shell model (LSSM) with the Hartree–Fock method. In this context, the elastic and inelastic electron scattering form factors, energy levels and reduced transition probabilities have been calculated for positive and negative low-lying states. The truncated large-scale spsdpf shell model space with WBP two-body effective interaction has been adopted to demonstrate the method's feasibility. The radial wave functions for the single-particle matrix elements were calculated using the Skyrme–Hartree–Fock with different parameterizations for all excited states. Moreover, the calculated results have been compared with available experimental data to identify which parameterizations introduced equivalent results to the experimental data. The results conducted that combining the shell model with Skyrme–Hartree–Fock yielded significant reproduction of both positive and negative parity states. [ABSTRACT FROM AUTHOR]

Nuclear morphology of carcinoma cells is critical for the pathological diagnosis of papillary thyroid carcinoma (PTC). However, three‐dimensional architecture of PTC nuclei is still elusive. In this study, we analyzed the three‐dimensional ultrastructure of PTC nuclei using serial block‐face scanning electron microscopy which takes advantage of the high‐throughput acquisition of serial electron microscopic images and three‐dimensional reconstruction of subcellular structures. En bloc‐stained and resin‐embedded specimens were prepared from surgically removed PTCs and normal thyroid tissues. We acquired two‐dimensional images from serial block‐face scanning electron microscopy and reconstructed three‐dimensional nuclear structures. Quantitative comparisons showed that the nuclei of carcinoma cells were larger and more complex than those of normal follicular cells. The three‐dimensional reconstruction of carcinoma nuclei divided intranuclear cytoplasmic inclusions into "open intranuclear cytoplasmic inclusions" connecting to cytoplasm outside the nucleus and "closed intranuclear cytoplasmic inclusions" without that connection. Cytoplasm with abundant organelles was observed in open inclusions, but closed inclusions contained fewer organelles with or without degeneration. Granules with a dense core were only observed in closed inclusions. Our observations suggested that open inclusions originate from nuclear invaginations, and disconnection from cytoplasm leads to closed inclusions. [ABSTRACT FROM AUTHOR]

Paraspeckles (PS) are nuclear structures scaffolded by the long noncoding RNA NEAT1 and protein components such as NONO and SFPQ. We previously found that the upregulation of RNA N6-methyl-adenosine (m6 A) demethylase ALKBH5 facilitates hypoxia-induced paraspeckle assembly through erasing m6 A marks on NEAT1, thus stabilizing it. However, it remains unclear how these processes are spatiotemporally coordinated. Here we discover that ALKBH5 specifically binds to proteins in PS and forms phase-separated droplets that are incorporated into PS through its C-terminal intrinsically disordered region (cIDR). Upon exposure to hypoxia, rapid ALKBH5 condensation in PS induces m6 A demethylation of NEAT1, which further facilitates PS formation before the upregulation of ALKBH5 expression. In cells expressing ALKBH5 lacking cIDR, PS fail to be formed in response to hypoxia, accompanied with insufficient m6 A demethylation of NEAT1 and its destabilization. We also demonstrate that ALKBH5-cIDR is indispensable for hypoxia-induced effects such as cancer cell invasion. Therefore, our study has identified the role of ALKBH5 in phase separation as the molecular basis of the positive feedback loop for PS formation between ALKBH5 incorporation into PS and NEAT1 stabilization. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work aims at presenting an alternative approach to the long standing problem of the B(E2) values in Sn isotopes in the vicinity of the N=Z double-magic nucleus 100Sn, until now predominantly measured with relativistic and intermediate-energy Coulomb excitation reactions. The direct measurement of the lifetime of low-lying excited states in odd-even Sn isotopes provides a new and precise guidance for the theoretical description of the nuclear structure in this region. Lifetime measurements have been performed in 105Sn for the first time with the coincidence Recoil Distance Doppler Shift technique. The lifetime results for the 7/21+ first excited state and the 11/21+ state, 2+(104Sn) ⊗ν1g7/2 multiplet member, are discussed in comparison with state-of-the-art shell model and mean field calculations, highlighting the crucial contribution of proton excitation across the core of 100Sn. The reduced transition probability B(E2) of the 11/21+ core-coupled state points out an enhanced staggering with respect to the B(E2; 21+→01+) in the even-mass 104Sn and 106Sn isotopes.

The chromatophores in Paulinella are evolutionary- early- stage photosynthetic organelles. Biological processes in chromatophores depend on a combination of chromatophore and nucleus- encoded proteins. Interestingly, besides proteins carrying chromatophore- targeting signals, a large arsenal of short chromatophore- targeted proteins (sCTPs; <90 amino acids) without recognizable targeting signals were found in chromatophores. This situation resembles endosymbionts in plants and insects that are manipulated by host- derived antimicrobial peptides. Previously, we identi- fied an expanded family of sCTPs of unknown function, named here "DNA- binding (DB)- sCTPs". DB- sCTPs contain a ~45 amino acid motif that is conserved in some bacterial proteins with predicted functions in DNA processing. Here, we explored antimicrobial activity, DNA- binding capacity, and structures of three purified recombinant DB- sCTPs. All three proteins exhibited antimicrobial activity against bacteria involving membrane permeabilization, and bound to bacterial lipids in vitro. A combination of in vitro assays demonstrated binding of recombinant DB- sCTPs to chromatophore- derived genomic DNA sequences with an affinity in the low nM range. Additionally, we report the 1.2 Å crystal structure of one DB- sCTP. In silico docking studies suggest that helix α2 inserts into the DNA major grove and the exposed residues, that are highly variable between different DB- sCTPs, confer interaction with the DNA bases. Identification of photosystem II subunit CP43 as a potential interaction partner of one DB- sCTP, suggests DB- sCTPs to be involved in more complex regulatory mechanisms. We hypothesize that membrane binding of DB- sCTPs is related to their import into chromatophores. Once inside, they interact with the chromatophore genome potentially providing nuclear control over genetic information processing. [ABSTRACT FROM AUTHOR]

The number of traditionally excellent coastal lithologic nuclear power plants is limited. It is a trend to develop nuclear power plants on soil sites in inland areas. Therefore, the seismic safety and adaptability of non-rock nuclear power plant (NPP) sites are the key concerns of nuclear safety researchers. Although the five site categories are clearly defined in the AP1000 design control documents, the effects of nuclear power five site conditions and soil nonlinearity on the seismic response characteristics of nuclear island buildings have not been systematically considered in previous related studies. In this study, targeting the AP1000 nuclear island structure as the research object, three-dimensional finite element models of a nuclear island structure at five types of sites (firm rock site (FR), soft rock site (SR), soft-to-medium soil site (SMS), upper bound soft-to-medium site (SMS-UB), and soft soil site (SS)) are established. The partitioned analysis method of soil-structure interaction (PASSI) in the time-domain is used to investigate the effects of site hardness and nonlinearity on the acceleration, displacement, and acceleration response spectrum of the nuclear island structure under seismic excitation. The incremental equilibrium equation and explicit decoupling method are used to analyze the soil nonlinearity described by the Davidenkov model with simplified loading-reloading rules. The results show that, in the linear case, with the increase of site hardness, the peak ground acceleration (PGA) and the peak of acceleration response spectrum of the nuclear island structure increase except for the FR site, while the maximum displacement decreases. In nonlinear analysis, as the site hardness increases, the PGA, maximum displacement, and the peak of acceleration response spectrum of the nuclear island structure increase. The peak value of the acceleration response spectrum in the nonlinear case is greater than that in the linear case for FR, while smaller for SR and soil sites. The site nonlinearity reduces the peak values of the response spectrum for SR and soil sites much more as the site hardness decreases. The results of this study can provide a reference for design of nuclear island structures on soil and rock sites. [ABSTRACT FROM AUTHOR]

In this study, the energy levels, electromagnetic transition probability, and charge density distribution of the 18O nucleus were calculated using the NuShellX@MSU code within the sdpn-shell and using the effective USDEPN and WCPN interactions. The charge density distribution values were also reasonably consistent with existing experimental data. Comparing the theoretical and experimental results indicates that applying the nuclear shell model using the USDEPN and WCPN interactions is successful within the sdpn-shell. [ABSTRACT FROM AUTHOR]

The Northeastern Pacific (NEP) population of white sharks (Carcharodon carcharias) is genetically distinct from the rest of the world. This uniqueness results from adult fidelity to central California and Guadalupe Island aggregations sites. The strong mitochondrial genetic structure between the white sharks of central California and Guadalupe Island is also present, which indicates female philopatry. To date, few studies using nuclear DNA have found evidence of genetic patterns in the NEP white shark population, which could indicate that these sharks exhibit sex-biased dispersal. In this study, we evaluated the genetic structure, connectivity, and genetic diversity of NEP white sharks using samples from the southern California Bight (SCB), Baja California (including Sebastian Vizcaino Bay), the Gulf of California, and Guadalupe Island (GI) using nDNA (i.e. microsatellite loci). A total of five loci were successfully genotyped in 54 individuals. The patterns found in this study indicated low levels of genetic diversity among all localities (observed heterozygosity: Ho = 0.47), likely due to a founder effect. A slight genetic structure was present for NEP localities in this study (FST = 0.045, P = 0.0001), mainly identified between the SCB and GI locations. A sibship assignment analysis indicated low and moderate probabilities of full- and half-siblings between white shark juveniles from coastal areas, suggesting a high degree of connectivity between nursery areas in the NEP. Our results suggest that juveniles can mask the genetic structure in coastal zones. [ABSTRACT FROM AUTHOR]

A modified Sood model was used to investigate the effects of rotation - vibration. As a consequence, it is indicated that the energy expression as a rational polynomial (RP) in total angular momentum I provides an excellent approximation to the ground state band excitation energies in U (A = 230-238). The shape of the nucleus in uranium even-even isotopes is controlled by a softness parameter, and the softness is believed to prevent the nucleus from becoming a rigid entity. The reason is discussed on the basis of the centrifugal stretching as well as the shrinkage. [ABSTRACT FROM AUTHOR]

The cumulative and independent yields of various fission products within the mass ranges of 83 to 117 and 123 to 161 have been measured in the epi-cadmium neutron-induced fission of 245Cm by using an off-line gamma-ray spectrometric technique. Charge distribution correction was applied on the cumulative yields to obtain the post-neutron mass yield distribution. From the mass yield distribution data, the full-width at tenth-maximum of light and heavy mass wings, average light mass and heavy mass , average neutron number <ν>, and peak-to-valley ratio were obtained for the first time. Comparison of mass yield distributions was made between the epi-cadmium and thermal neutron–induced fission of 245Cm to examine the role of excitation energy on the nuclear structure effect and P/V ratio. [ABSTRACT FROM AUTHOR]

In the epi-cadmium neutron-induced fission of 229Th, cumulative yields of relatively long-lived fission products within the mass range of 77 to 151 were measured by using an off-line gamma-ray spectrometric technique. The mass yields were obtained from the cumulative fission product yields by using charge distribution correction. The peak-to-valley (P/V) ratio, full-width at tenth-maximum of light and heavy mass wings, average light mass and heavy mass , and average neutron number <ν> were obtained. The P/V ratio was obtained for the first time and was found to be about three times lower in the epi-cadmium neutron fission than in the thermal neutron fission of 229Th, which shows the role of excitation energy. The fine structure of the mass yield distribution in the 229Th(nf,f) reaction was explained from the viewpoint of nuclear structure effect and the Standard I and Standard II asymmetric modes of fission. [ABSTRACT FROM AUTHOR]

High-energy γ rays are emitted either in the decay of nuclear discrete states (generally located in the proximity of the particle-emission threshold) or in the electromagnetic decay of collective states. The branching ratio is rather small, therefore in alternative/coincidence with high-energy γ rays one could have neutron or charged-particle emission. The precise measurement of these branching ratios allows a more comprehensive description of the nucleus and, in particular, the selection of the nuclear models which better describes the interplay between the different acting forces and couplings. In the case of the electromagnetic decay of collective states, the precise identification of the populated low-lying states allows the measurement of their wave-function and/or of their 'bulk' properties. This information provides, also in this case, a stringent test for the nuclear models. In both cases, to compensate these small branching ratio, a large number of detectors and an accurate selection of a small region of the phase space are needed. AGATA is considered to constitute an optimal array for this kind of measurements. In fact, AGATA, because of its high granularity and its excellent energy resolution, can detect the high-energy γ rays emitted in a specific decay path or associated to specific reaction channels, shapes, deformations. In the introduction, some details on the measurement of high-energy γ rays using HPGe detector are discussed. The sections of this paper focus on the measurements of high-energy γ rays to obtain the photon strength function, the nuclear level density and to identify extreme shapes in highly excited nuclei. [ABSTRACT FROM AUTHOR]

The Brink–Axel hypothesis, which states that the photoabsorption cross section is independent of the excitation energy of a nuclear system, is an assumption used in nuclear structure studies and calculations of neutron-capture cross section for astrophysical applications. In the present work, using microscopic Configuration Interaction method, it is demonstrated that the dipole photoabsorption cross section at low energy is dependent on the excitation energy and deviations from the Brink-Axel hypothesis are particularily large for the ground state of an even-even system. It is also shown that the low-lying E1-strength, known as pygmy dipole resonance, is redistributed with the excitation energy of the initial state and strongly dependent on its structure. The consequences of these findings on the calculated neutron-capture cross sections are discussed. [ABSTRACT FROM AUTHOR]

Using an extended parity doublet model with the hidden local symmetry, we study some properties of nuclei in the mean field approximation to see if the parity doublet model could reproduce nuclear properties and also to estimate the value of the chiral invariant nucleon mass m 0 preferred by nuclear structure. We first determine our model parameters using the inputs from free space and from nuclear matter properties. Then, we study some basic nuclear properties such as the nuclear binding energy with several different choices of the chiral invariant mass. We observe that our results approach the experimental values as m 0 is increased until m 0 = 700 MeV and start to deviate more from the experiments afterwards with m 0 larger than m 0 = 700 MeV. From this observation, we conclude that m 0 = 700 MeV is preferred by nuclear properties. We then calculate some properties of several selected nuclei with m 0 = 700 MeV and compare them with experiments. Finally, we study the neutron-proton mass difference in some nuclei. [ABSTRACT FROM AUTHOR]

Nuclear-structure studies using fusion reactions are reviewed in terms of prospects for advancement using the next generation of γ -ray tracking arrays such as AGATA. Properties discussed include those of light N = Z nuclei and rotational behaviour in heavy nuclei at high values of angular momentum and internal excitation energy. [ABSTRACT FROM AUTHOR]

When misfolded intermediates accumulate during heat shock, the protein quality control system promotes cellular adaptation strategies. In Schizosaccharomyces pombe, thermo-sensitive proteins assemble upon stress into protein aggregate-like centers, PACs, to escape from degradation. The role of this protein deposition strategy has been elusive due to the use of different model systems and reporters, and to the addition of artificial inhibitors, which made interpretation of the results difficult. Here, we compare fission and budding yeast model systems, expressing the same misfolding reporters in experiments lacking proteasome or translation inhibitors. We demonstrate that mild heat shock triggers reversible PAC formation, with the collapse of both reporters and chaperones in a process largely mediated by chaperones. This assembly postpones proteasomal degradation of the misfolding reporters, and their Hsp104-dependent disassembly occurs during stress recovery. Severe heat shock induces formation of cytosolic PACs, but also of nuclear structures resembling nucleolar rings, NuRs, presumably to halt nuclear functions. Our study demonstrates that these distantly related yeasts use very similar strategies to adapt and survive to mild and severe heat shock and that aggregate-like formation is a general cellular scheme to postpone protein degradation and facilitate exit from stress. [ABSTRACT FROM AUTHOR]

Nuclear morphology changes during senescence and may potentially underlie other molecular changes. LncRNAs play architectural roles in the nucleus and change in abundance during aging and senescence. RNA-dsDNA base pairing facilitates aging-associated lncRNAs in their interactions with nuclear proteins and DNAs. A future direction is to combine artificial intelligence and CRISPR to directly fine-map lncRNAs' roles in nuclear architecture during aging. During cellular senescence and organismal aging, cells display various molecular and morphological changes. Although many aging-related long noncoding RNAs (lncRNAs) are highly associated with senescence-associated secretory phenotype, the roles of lncRNAs in senescence-associated nuclear architecture and morphological changes are just starting to emerge. Here I review lncRNAs associated with nuclear structure establishment and maintenance, their aging-related changes, and then focus on the pervasive, yet underappreciated, role of RNA double-strand DNA triplexes for lncRNAs to recognize targeted genomic regions, making lncRNAs the nexus between DNA and proteins to regulate nuclear structural changes. Finally, I discuss the future of deciphering direct links of lncRNA changes to various nuclear morphology changes assisted by artificial intelligence and genetic perturbations. [ABSTRACT FROM AUTHOR]