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Nitrogen is an essential element required for plant growth and productivity. Understanding the mechanisms and natural genetic variation underlying nitrogen use in plants will facilitate the engineering of plant nitrogen use to maximize crop productivity while minimizing environmental costs. To understand the scope of natural variation that may influence nitrogen use, we grew 1,135 Arabidopsis thaliana natural genotypes on two nitrogen sources, nitrate and ammonium, and measured both developmental and defense metabolite traits. By using different environments and focusing on multiple traits, we identified a wide array of different nitrogen responses. These responses are associated with numerous genes, most of which were not previously associated with nitrogen responses. Only a small portion of these genes appear to be shared between environments or traits, while most are predominantly specific to a developmental or defense trait under a specific nitrogen source. Finally, by using a large population, we were able to identify unique nitrogen responses, such as preferring ammonium or nitrate, which appear to be generated by combinations of loci rather than a few large-effect loci. This suggests that it may be possible to obtain novel phenotypes in complex nitrogen responses by manipulating sets of genes with small effects rather than solely focusing on large-effect single gene manipulations.

In situ shell-isolated nanoparticle-enhanced Raman spectroscopy provides molecular-level insights into the electroreductive dehalogenation mechanism of aryl halides.

We review the physics of hyperons and $\Delta$-resonances in dense matter in compact stars. The covariant density functional approach to the equation of state and composition of dense nuclear matter in the mean-field Hartree and Hartree-Fock approximation is presented, with regimes covering cold $\beta$-equilibrated matter, hot and dense matter with and without neutrinos relevant for the description of supernovas and binary neutron star mergers, as well as dilute expanding nuclear matter in collision experiments. We discuss the static properties of compact stars with hyperons and $\Delta$-resonances in light of constraints placed in recent years by the multimessenger astrophysics of compact stars on the compact stars' masses, radii, and tidal deformabilities. The effects of kaon condensation and strong magnetic fields on the composition of hypernuclear stars are also discussed. The properties of rapidly rotating compact hypernuclear stars are discussed and confronted with the observations of 2.5-2.8 solar mass compact objects in gravitational wave events. We further discuss the cooling of hypernuclear stars, the neutrino emission reactions, hyperonic pairing, and the mass hierarchy in the cooling curves that arises due to the onset of hyperons. The effects of hyperons and $\Delta$-resonances on the equation of state of hot nuclear matter in the dense regime, relevant for the transient astrophysical event and in the dilute regime relevant to the collider physics is discussed. The review closes with a discussion of universal relations among the integral parameters of hot and cold hypernuclear stars and their implications for the analysis of binary neutron star merger events., Comment: v3 and v2: 79 pages, 26 figures, final version (minor changes and additions, typos corrected). v1: 76 pages, 26 figures. arXiv admin note: text overlap with arXiv:2105.14050

Nitrogen is an essential element required for plant growth and productivity. Understanding the mechanisms and natural genetic variation underlying nitrogen use in plants will facilitate engineering plant nitrogen use to maximize crop productivity while minimizing environmental costs. To understand the scope of natural variation that may influence nitrogen use, we grew 1135 Arabidopsis thaliana natural genotypes on two nitrogen sources, nitrate and ammonium, and measured both developmental and defense metabolite traits. By using different environments and focused on multiple traits, we identified a wide array of different nitrogen responses. These responses are associated with a large number of genes, most of them not previously associated with nitrogen responses. Only a small portion of these genes appear to be shared between environments or traits while most of the detected genes are predominantly specific to a developmental or defense trait under a specific nitrogen source. Finally, by using a large population we were able to identify unique nitrogen responses, like preferring ammonium or nitrate, that appear to be generated by combinations of loci rather than a few large effect loci. This suggests that it may be possible to obtain novel phenotypes in complex nitrogen responses by manipulating sets of genes with small effects rather than solely focusing on large effect single gene manipulations.One Sentence SummaryUsing a large collection of natural genotypes, and studying both developmental and metabolic responses, we found a large number of genes that are involved in the plants nitrogen response.

We construct a new equation of state for the baryonic matter under an intense magnetic field within the framework of covariant density functional theory. The composition of matter includes hyperons as well as &Delta, resonances. The extension of the nucleonic functional to the hypernuclear sector is constrained by the experimental data on &Lambda, and &Xi, hypernuclei. We find that the equation of state stiffens with the inclusion of the magnetic field, which increases the maximum mass of neutron star compared to the non-magnetic case. In addition, the strangeness fraction in the matter is enhanced. Several observables, like the Dirac effective mass, particle abundances, etc. show typical oscillatory behavior as a function of the magnetic field and/or density which is traced back to the occupation pattern of Landau levels.

In this work, we consider the consequences of phase transition in dense QCD on the properties of compact stars and implications for the observational program in gravitational wave and X-ray astrophysics. The key underlying assumption of our modeling is a strong first-order phase transition past the point where the hadronic branch of compact stars reaches the two-solar mass limit. Our analysis predicts ultracompact stars with very small radii - in the range of 6-9 km - living on compact star sequences that are entirely consistent with the current multimessenger data. We show that sequences featuring two-solar mass hadronic stars consistent with radio-pulsar observations are also consistent with the inferences of large radii for massive neutron stars by NICER X-ray observations of neutron stars and the small radii predicted by gravitational waves analysis of the binary neutron star inspiral event GW170817 for our models that feature a strong first-order QCD phase transition., Comment: v2: matches published version, 6 pages, 5 figures

The increase of neutron flux in pulsed spallation neutron facilities imposes demands on the neutron detector for beam monitoring, including excellent neutron/gamma discrimination, wide dynamic neutron-flux measurement range, wavelength resolution, and long-term stability. In this paper, we developed a ceramic GEM-based (gas electron multiplier) neutron detector with an active area of 100 mm × 100 mm. It adopted a thinner conversion material and the stopping layer to lower the detection efficiency so as to extend the dynamic measurement range of the detector. The detection efficiency of this detector was investigated by the Monte Carlo (MC) tool FLUKA, showing that the low efficiency around 0.01% for 1 Åneutrons was reached by using a 0.1 μm natB4C converter appended with an aluminum film of 2 μm thickness. Its validation of the wavelength spectra measurement was verified by comparisons with that made with an LND monitor, and it could work at the condition of 7.1 × 109 n/s for 2.5 Åneutrons. In addition, it was demonstrated that this detector was able to measure the beam profile with a position resolution of better than 2.1 ± 0.1 mm. The results of simulations and experiments show that this ceramic-GEM neutron detector can meet the requirements of the direct measurement of high-flux beam, and it will be a new neutron detector for the beam monitoring at the China spallation neutron source (CSNS).

Plant metabolism is more complex relative to individual microbes. In single‐celled microbes, transcriptional regulation by single transcription factors (TFs) is sufficient to shift primary metabolism. Corresponding genome‐level transcriptional regulatory maps of metabolism reveal the underlying design principles responsible for these shifts as a model in which master regulators largely coordinate specific metabolic pathways. Plant primary and specialized metabolism occur within innumerable cell types, and their reactions shift depending on internal and external cues. Given the importance of plants and their metabolites in providing humanity with food, fiber, and medicine, we set out to develop a genome‐scale transcriptional regulatory map of Arabidopsis metabolic genes. A comprehensive set of protein–DNA interactions between Arabidopsis thaliana TFs and gene promoters in primary and specialized metabolic pathways were mapped. To demonstrate the utility of this resource, we identified and functionally validated regulators of the tricarboxylic acid (TCA) cycle. The resulting network suggests that plant metabolic design principles are distinct from those of microbes. Instead, metabolism appears to be transcriptionally coordinated via developmental‐ and stress‐conditional processes that can coordinate across primary and specialized metabolism. These data represent the most comprehensive resource of interactions between TFs and metabolic genes in plants., A transcription factor‐promoter interaction network of primary and specialized metabolism in Arabidopsis thaliana reveals transcriptional coordination across multiple metabolic pathways that is developmental and stress condition‐dependent.

SummaryIn single-celled microbes, transcriptional regulation by single transcription factors is sufficient to shift primary metabolism. Corresponding genome-level transcriptional regulatory maps of metabolism reveal the underlying design principles responsible for these shifts as a model in which master regulators largely coordinate specific metabolic pathways. Relative to individual microbes, plant metabolism is more complex. Primary and specialized metabolism occur within innumerable cell types, and their reactions shift depending on internal and external cues. Given the importance of plants and their metabolites in providing humanity with food, fiber and medicine, we set out to develop a genome-scale transcriptional regulatory map of Arabidopsis metabolic genes. A comprehensive set of protein-DNA interactions between Arabidopsis thaliana transcription factors and promoters of primary metabolism and specialized metabolism were mapped. To demonstrate the utility of this resource, we identified and functionally validated regulators of the TCA cycle. The resulting network suggests that plant metabolic design principles are distinct from that of microbes. Instead, metabolism appears to be transcriptionally coordinated via developmental- and stress-conditional processes that can coordinate across primary and specialized metabolism. These data represent the most comprehensive resource of interactions between TFs and metabolic genes in plants.

Plants produce diverse metabolites to cope with the challenges presented by complex and ever-changing environments. These challenges drive the diversification of specialized metabolites within and between plant species. However, we are just beginning to understand how frequently new alleles arise controlling specialized metabolite diversity and how the geographic distribution of these alleles may be structured by ecological and demographic pressures. Here, we measure the variation in specialized metabolites across a population of 797 natural Arabidopsis thaliana accessions. We show that a combination of geography, environmental parameters, demography and different genetic processes all combine to influence the specific chemotypes and their distribution. This showed that causal loci in specialized metabolism contain frequent independently generated alleles with patterns suggesting potential within-species convergence. This provides a new perspective about the complexity of the selective forces and mechanisms that shape the generation and distribution of allelic variation that may influence local adaptation., eLife digest Since plants cannot move, they have evolved chemical defenses to help them respond to changes in their surroundings. For example, where animals run from predators, plants may produce toxins to put predators off. This approach is why plants are such a rich source of drugs, poisons, dyes and other useful substances. The chemicals plants produce are known as specialized metabolites, and they can change a lot between, and even within, plant species. The variety of specialized metabolites is a result of genetic changes and evolution over millions of years. Evolution is a slow process, yet plants are able to rapidly develop new specialized metabolites to protect them from new threats. Even different populations of the same species produce many distinct metabolites that help them survive in their surroundings. However, the factors that lead plants to produce new metabolites are not well understood, and it is not known how this affects genetic variation. To gain a better understanding of this process, Katz et al. studied 797 European variants of a common weed species called Arabidopsis thaliana, which is widely studied. The investigation found that many factors affect the range of specialized metabolites in each variant. These included local geography and environment, as well as genetics and population history (demography). Katz et al. revealed a pattern of relationships between the variants that could mirror their evolutionary history as the species spread and adapted to new locations. These results highlight the complex network of factors that affect plant evolution. Rapid diversification is key to plant survival in new and changing environments and has resulted in a wide range of specialized metabolites. As such they are of interest both for studying plant evolution and for understanding their ecology. Expanding similar work to more populations and other species will broaden the scope of our ability to understand how plants adapt to their surroundings.

Nicotinamide phosphoribosyltransferase (NAMPT) is a critical rate-limiting enzyme involved in NAD synthesis that has been shown to contribute to the progression of liver cancer. However, the potential role and mechanism of NAMPT in hepatitis B virus (HBV)-associated liver cancer remain unclear. The present study assessed the expression of NAMPT in HBV-positive and -negative liver cancer cells, and investigated whether HBV-induced NAMPT expression is dependent on HBV X protein (HBx). In addition, the role of NAMPT in HBV replication and transcription, and in HBV-mediated liver cancer cell growth was explored. The effects of NAMPT on the glycolytic pathway were also evaluated. Reverse transcription-quantitative PCR and western blotting results revealed that NAMPT expression levels were significantly higher in HBV-positive liver cancer cells than in HBV-negative liver cancer cells, and this effect was HBx-dependent. Moreover, the activation of NAMPT was demonstrated to be required for HBV replication and transcription. The NAMPT inhibitor FK866 repressed cell survival and promoted cell death in HBV-expressing liver cancer cells, and these effects were attenuated by nicotinamide mononucleotide. Furthermore, the inhibition of NAMPT was associated with decreased glucose uptake, decreased lactate production and decreased ATP levels in HBV-expressing liver cancer cells, indicating that NAMPT may promote the aerobic glycolysis. Collectively, these findings reveal a positive feedback loop in which HBV enhances NAMPT expression and the activation of NAMPT promotes HBV replication and HBV-mediated malignant cell growth in liver cancer. The present study highlights the important role of NAMPT in the regulation of aerobic glycolysis in HBV-mediated liver cancer, and suggests that NAMPT may be a promising treatment target for patients with HBV-associated liver cancer.

In this work, we study the effect of (anti)kaon condensation on the properties of compact stars that develop hypernuclear cores with and without an admixture of $\Delta$-resonances. We work within the covariant density functional theory with the parameters adjusted to $K$-atomic and kaon-nucleon scattering data in the kaonic sector. The density-dependent parameters in the hyperonic sector are adjusted to the data on $\Lambda$ and $\Xi^-$ hypernuclei data. The $\Delta$-resonance couplings are tuned to the data obtained from their scattering off nuclei and heavy-ion collision experiments. We find that (anti)kaon condensate leads to a softening of the equation of state and lower maximum masses of compact stars than in the absence of the condensate. Both the $K^-$ and $\bar K^0$-condensations occur through a second-order phase transition, which implies no mixed-phase formation. For large values of (anti)kaon and $\Delta$-resonance potentials in symmetric nuclear matter, we observe that condensation leads to an extinction of $ \Xi^{-,0}$ hyperons. We also investigate the influence of inclusion of additional hidden-strangeness $\sigma^{*}$ meson in the functional and find that it leads to a substantial softening of the equation of state and delay in the onset of (anti)kaons., Comment: 14 pages, 11 figures, accepted for publication in Phys. Rev. D

New Delhi metallo-β-lactamase (NDM) had been reported to be the predominant carbapenemase among Escherichia coli in Taiwan. However, studies focusing on the clonal background and epidemiology of plasmids carrying NDM genes were limited. Between 2016 and 2018, all clinical E. coli and Klebsiella pneumoniae isolates that were non-susceptible to ertapenem, meropenem, and imipenem were tested for carbapenemase-encoding genes (CEGs) and antimicrobial susceptibilities. Molecular typing was performed on all carbapenemase-producing isolates. Whole genome sequencing (WGS) was performed on all NDM-positive E. coli isolates. Twenty-three (29.5%) of 78 carbapenem non-susceptible E. coli and 108 (35.3%) of 306 carbapenem non-susceptible K. pneumoniae isolates carried CEGs. The most prevalent CEGs in carbapenemase-producing E. coli (CPEc) were blaNDM (39.1%) and blaIMP-8 (30.4%), while that in carbapenemase-producing K. pneumoniae was Klebsiella pneumoniae carbapenemase (KPC) (72.2%). Fifteen sequence types were identified among 23 CPEc, and 55.6% of NDM-positive E. coli isolates belonged to ST410. WGS showed ST410 isolates were highly clonal and similar to those from other countries. All NDM-5-positive E. coli isolates carried identical IncX3 plasmid harboring blaNDM-5 but no other antimicrobial resistance (AMR) genes. In each of the four NDM-1-positive E. coli isolates, the blaNDM-1 was present in a ∼ 300 kb IncHI2/IncHI2A plasmid which carried an array of AMR genes. NDMs are the most prevalent carbapenemase among CPEc in Taiwan. Awareness should be raised as the prevalence of NDM-positive E. coli might increase rapidly with IncX3 plasmid and globally distributed strain ST410 being the potential vectors for wide dissemination.

We examine the possibility that the light companion in the highly asymmetric binary compact object coalescence event GW190814 is a hypernuclear star. We use density functional theory with functionals that have been tuned to the properties of $\Lambda$ hypernuclei as well as astrophysical constraints placed by the masses of the most massive millisecond pulsars, the mass-radius range inferred from the NICER experiment, and the binary neutron star merger event GW170817. We compute general-relativistic static and maximally rotating Keplerian configurations of purely nucleonic and hypernuclear stars. We find that while nucleonic stars are broadly consistent with a neutron star being involved in GW190814, this would imply no new degrees of freedom in the dense matter up to 6.5 times the nuclear saturation density. Allowing for hyperonization of dense matter, we find that the maximal masses of hypernuclear stars, even for maximal rapidly rotating configurations, are inconsistent with a stellar nature interpretation of the light companion in GW190814, implying that this event involved two black holes rather than a neutron star and a black hole., Comment: 5 pages, 4 figures; v2: minor editorial improvements, matches published version

The $\Delta$-isobar degrees of freedom are included in the covariant density functional (CDF) theory to study the equation of state (EoS) and composition of dense matter in compact stars. In addition to $\Delta$'s we include the full octet of baryons, which allows us to study the interplay between the onset of delta isobars and hyperonic degrees of freedom. Using both the Hartree and Hartree-Fock approximation we find that $\Delta$'s appear already at densities slightly above the saturation density of nuclear matter for a wide range of the meson-$\Delta$ coupling constants. This delays the appearance of hyperons and significantly affects the gross properties of compact stars. Specifically, $\Delta$'s soften the EoS at low densities but stiffen it at high densities. This softening reduces the radius of a canonical $1.4 M_\odot$ star by up to 2~km for a reasonably attractive $\Delta$ potential in matter, while the stiffening results in larger maximum masses of compact stars. We conclude that the hypernuclear CDF parametrizations that satisfy the 2$M_\odot$ maximum mass constraint remain valid when $\Delta$ isobars are included, with the important consequence that the resulting stellar radii are shifted toward lower values, which is in agreement with the analysis of neutron star radii., Comment: 7 pages, 4 figures; v2: minor changes, matches published version

Virus-modified T cells are approved for cancer immunotherapy, but more versatile and precise genome modifications are needed for a wider range of adoptive cellular therapies1–4. We recently developed a non-viral CRISPR–Cas9 system for genomic site-specific integration of large DNA sequences in primary human T cells5. Here, we report two key improvements for efficiency and viability in an expanded variety of clinically-relevant primary cell types. We discovered that addition of truncated Cas9 target sequences (tCTS) at the ends of the homology directed repair (HDR) templates can interact with Cas9 ribonucleoproteins (RNPs) to ‘shuttle’ the template and enhance targeting efficiency. Further, stabilizing the Cas9 RNPs into nanoparticles with poly(glutamic acid) improved editing, reduced toxicity, and enabled lyophilized storage without loss of activity. Combining the tCTS HDR template modifications with polymer-stabilized nanoparticles increased gene targeting efficiency and viable cell yield across multiple genomic loci in diverse cell types. This system is an inexpensive, user-friendly delivery platform for non-viral genome reprogramming that we successfully applied in regulatory T cells (Tregs), γδ-T cells, B cells, NK cells, and primary and iPS-derived6 hematopoietic stem progenitor cells (HSPCs).

The thermal evolution of hypernuclear compact stars is studied for stellar models constructed on the basis of covariant density functional theory in Hartree and Hartree-Fock approximation. Parametrizations of both types are consistent with the astrophysical mass constraints on compact stars and available hypernuclear data. We discuss the differences of these density functionals and highlight the effects they have on the composition and on the cooling of hypernuclear stars. It is shown that hypernuclear stars computed with density functional models that have a low symmetry energy slope, $L$, are fairly consistent with the cooling data of observed compact stars. The class of stellar models based on larger $L$ values gives rise to the direct Urca process at low densities, which leads to significantly faster cooling. We conjecture high-density pairing for protons and $\Lambda$'s in the $P$-wave channel and provide simple scaling arguments to obtain these gaps. As a consequence the most massive stellar models with masses $1.8 \le M/M_{\odot} \le2$ experience slower cooling by hyperonic dUrca processes which involve $\Lambda$'s and protons., Comment: 15 pages, 8 figures

We compute the mass, radius and tidal deformability of stars containing phase transitions from hadronic to quark phase(s). These quantities are computed for three types of hadronic envelopes: purely nuclear, hyperonic, and $\Delta$-resonance--hyperon admixed matter. We consider either a single first-order phase transition to a quark phase with a maximally stiff equation of state (EOS) or two sequential first-order phase transitions mimicking a transition from hadronic to a quark matter phase followed by a second phase transition to another quark phase. We explore the parameter space which produces low-mass twin and triplet configurations where equal-mass stars have substantially different radii and tidal deformabilities. We demonstrate that while for purely hadronic stiff EOS the obtained maximum mass is inconsistent with the upper limit on this quantity placed by GW170817, the inclusion of the hyperonic and $\Delta$-resonance degrees of freedom, as well as the deconfinement phase transition at sufficiently low density, produces a configuration of stars consistent with this limit. The obtained hybrid star configurations are in the mass range relevant for the interpretation of the GW170817 event. We compare our results for the tidal deformability with the limits inferred from GW170817 showing that the onset of non-nucleonic phases, such as $\Delta$-resonance--hyperon admixed phase and/or the quark phase(s), are favored by this data if the nuclear EOS is stiff. Also, we show that low-mass twins and especially triplets proliferate the number of combinations of possible types of stars that can undergo a merger event, the maximal number being six in the case of triplets. The prospects for uncovering the first-order phase transition(s) to and in quark matter via measurements of tidal deformabilities in merger events are discussed., Comment: 11 pages, 9 figures, 5 tables; minor corrections, matches published version

A set of hadronic equations of state (EoSs) derived from relativistic density functional theory and constrained by terrestrial experiments, astrophysical observations, in particular by the GW170817 event, and chiral effective field theory ($\chi$EFT) of neutron matter is used to explore the sensitivity of the EoS parameterization on the few nuclear matter characteristics defined at the saturation density. We find that the gross properties of compact stars are most sensitive to the isoscalar skewness coefficient $Q_{\text{sat}}$ and the isovector slope coefficient $L_{\text{sym}}$ around saturation density, since the higher order coefficients, such as $K_{\text{sym}}$, are fixed by our model. More specifically, (i) among these $Q_{\text{sat}}$ is the dominant parameter controlling both the maximum mass and the radii of compact stars while $L_{\rm sym}$ is constrained somewhat by $\chi$EFT of neutron matter; (ii) massive enough ($M\sim 2.0~M_{\odot})$ compact stars featuring both hyperons and $\Delta$ resonances can be obtained if the value of $Q_{\text{sat}}$ is large enough; (iii) the emergence of $\Delta$'s reduces the radius of a canonical mass ($M\sim 1.4~M_{\odot})$ compact star thus easing the tension between the predictions of the relativistic density functionals and the inferences from the X-ray observation of nearby isolated neutron stars., Comment: 13 pages, 11 figures, 3 tables. Discussions and references added. Phys. Rev. C in press

Using the relativistic Hartree–Fock Lagrangian PKA1, we investigate the properties of the exotic nucleus 48Si, which is predicted to be an atypical nucleus characterized by i) the onset of doubly magicity, ii) its location at the drip line, iii) the presence of dual semi-bubble structure (distinct central depletion in both of neutron and proton density profiles) in the ground state, and iv) the occurrence of pairing reentrance at finite temperature. While not being new for each, these phenomena are found to simultaneously occur in 48Si. For instance, the dual semi-bubble structure reduces the spin–orbit splitting of low-ℓ orbitals and upraises the s orbitals, leading therefore to distinct N=34 and Z=14 magic shells in 48Si. Consequently, the doubly magicities provide extra stability for such extreme neutron-rich system at the drip line. Associating with the neutron shell N=34 and continuum above, the pairing correlations are reengaged interestingly at finite temperature. Theoretical nuclear modelings are known to be poorly predictive in general, and we asset our confidence in the prediction of our modeling on the fact that the predictions of PKA1 in various regions of the nuclear chart have systematically been found correct and more specifically in the region of pf shell. Whether our predictions are confirmed or not, 48Si provides a concrete benchmark for the understanding of the nature of nuclear force. Keywords: New magicity, Drip-line nucleus, Bubble-like structure, Pairing reentrance

The mechanism that restores the pseudo-spin symmetry (PSS) are investigated under the relativistic Hartree-Fock (RHF) approach, by focusing on the in-medium balance between nuclear attractive and repulsive interactions. It is illustrated that the modelings of both the equilibrium of nuclear dynamics and the in-medium effects can be essentially changed by the $\rho$-tensor coupling that play the role almost fully via the Fock terms, from which the model discrepancy on the PSS restoration is verified. Specifically, the largely different density-dependent behaviors of the isoscalar coupling strengths $g_\sigma$ and $g_\omega$, deduced from the parametrization of the RHF Lagrangian PKA1, play an essential role in restoring the PSS of the high-$l'$ pseudo-spin doublets around the Fermi levels. Qualitatively, a guidance is provided for the modelings of both the equilibrium of nuclear dynamics and the in-medium effects via the PSS restoration., Comment: 3 figures and 2 tables

The formation of new shell gaps in intermediate mass neutron-rich nuclei is investigated within the relativistic Hartree-Fock-Bogoliubov theory, and the role of the Lorentz pseudo-vector and tensor interactions is analyzed. Based on the Foldy-Wouthuysen transformation, we discuss in detail the role played by the different terms of the Lorentz pseudo-vector and tensor interactions in the appearing of the $N=16$, 32 and 34 shell gaps. The nuclei $^{24}$O, $^{48}$Si and $^{52,54}$Ca are predicted with a large shell gap and zero ($^{24}$O, $^{52}$Ca) or almost zero ($^{48}$Si, $^{54}$Ca) pairing gap, making them candidates for new magic numbers in exotic nuclei. We find from our analysis that the Lorentz pseudo-vector and tensor interactions induce very specific evolutions of single-particle energies, which could clearly sign their presence and reveal the need for relativistic approaches with exchange interactions., 7 pages, 5 figures, 1 table

We use a set of hadronic equations of state derived from covariant density functional theory to study the impact of their high-density behavior on the properties of rapidly rotating $\Delta$-resonance-admixed hyperonic compact stars. In particular, we explore systematically the effects of variations of the bulk energy isoscalar skewness, $Q_{\mathrm{sat}}$, and the symmetry energy slope, $L_{\mathrm{sym}}$, on the masses of rapidly rotating compact stars. With models for equation of state satisfying all the modern astrophysical constraints, excessively large gravitational masses of around $2.5 \, M_{\odot}$ are only obtained under three conditions: (a) strongly attractive $\Delta$-resonance potential in nuclear matter, (b) maximally fast (Keplerian) rotation, and (c) parameter ranges $Q_{\mathrm{sat}}\gtrsim500$ MeV and $L_{\mathrm{sym}}\lesssim50$ MeV. These values of $Q_{\mathrm{sat}}$ and $L_{\mathrm{sym}}$ have a rather small overlap with a large sample (total of about 260) parametrizations of covariant nucleonic density functionals. The extreme nature of requirements (a)-(c) reinforces the theoretical expectation that the secondary object involved in the GW190814 event is likely to be a low-mass black hole rather than a supramassive neutron star., Comment: 8 pages with 5 figures, matches published version

To investigate the effect of Toxoplasma gondii rhoptry protein 17（ROP17） on γ-interferon (IFN-γ)-induced apoptosis of mouse J774A.1 monocyte macrophages.The J774A.1 cells were transfected with recombinant plasmid p3×Flag-CMV-14/TgROP17 or empty plasmid p3×Flag-CMV-14. After addition of IFN-γ, flow cytometry and Western blotting were performed to detect apoptosis and the protein levels of phosphorylated c-Jun and apoptosis-related proteins cleaved Caspase-3, Bcl-2, Bcl-xL and Bcl-3. The p3×Flag-CMV-14/TgROP17 plasmid and c-Jun shRNA were co-transfected into J774A.1 cells, after which IFN-γ was added to induce cell apoptosis. The levels of cleaved Caspase-3 and Bcl-3 were analyzed using Western blotting.Flow cytometry showed that the apoptosis rate of cells overexpressing ROP17［（3.73±0.51）%］ was significantly lower than that of the control cells［（7.78±1.10）%, P0.05］. Western blotting showed significant differences in protein levels of phosphorylated c-Jun（0.196±0.028 vs. 0.075±0.010）, Bcl-3（0.461±0.063 vs. 0.108±0.013） and cleaved Caspase 3（0.015±0.004 vs. 0.174±0.026） between the cells overexpressing ROP17 and control cells （all P0.05）. However, the levels of Bcl-2 and Bcl-xL were not significantly different between the cells overexpressing ROP17 and the control. When the expression of c-Jun and phosphorylation of c-Jun were inhibited by c-Jun shRNA, the relative level of cleaved Caspase 3 in the RNA interferenced cells and control cells was 0.147±0.024 and 0.087±0.010, respectively (P0.05), and the relative level of Bcl-3 was 0.085±0.010 and 0.162±0.011, respectively (P0.05).The anti-apoptosis effect of ROP17 is dependent on the phosphorylation of c-Jun and the expression of Bcl-3.

The hypernuclear matter is studied within the relativistic Hartree-Fock theory employing several parametrizations of the hypernuclear density functional with density-dependent couplings. The equations of state and compositions of hypernuclear matter are determined for each parametrization and compact stars are constructed by solving their structure equations in spherical symmetry. We quantify the softening effect of Fock terms on the equation of state, as well as discuss the impact of tensor interactions, which are absent in the Hartree theories. Starting from models of density functionals which are fixed in the nuclear sector to the nuclear phenomenology, we vary the couplings in the hyperonic sector around the central values which are fitted to the hyperon potentials in nuclear matter. We use the SU(6) spin-flavor and SU(3) flavor symmetric quark models to relate the hyperonic couplings to the nucleonic ones. We find, consistent with previous Hartree studies, that for the SU(6) model the maximal masses of compact stars are below the two-solar mass limit. In the SU(3) model we find sufficiently massive compact stars with cores composed predominantly of $\Lambda$ and $\Xi$ hyperons and a low fraction of leptons (mostly electrons). The parameter space of the SU(3) model is identified where simultaneously hypernuclear compact stars obey the astrophysical limits on pulsar masses and the empirical hypernuclear potentials in nuclear matter are reproduced., Comment: v2: 22 pages, 14 figures, minor changes and clarifications, matches published version

Finite-temperature Hartree-Fock-Bogoliubov theory using Skyrme interactions and relativistic Hartree-Fock effective Lagrangians predicts $^{48}\mathrm{Ni}$ as being a possible candidate for the finite-temperature pairing re-entrance phenomenon. For this proton-drip-line nucleus, proton resonant states are expected to contribute substantially to pairing correlations and the two predicted critical temperatures are ${T}_{c1}\ensuremath{\sim}0.08--0.2$ MeV and ${T}_{c2}\ensuremath{\sim}0.7--0.9$ MeV. It is also shown that pairing re-entrance modifies the proton single-particle energies around the Fermi level, as well as occupation numbers and quasiparticle levels. The understanding of pairing re-entrance in $^{48}\mathrm{Ni}$ presently challenges our understanding of exotic matter under extreme conditions.

The effects of $\Delta$ isobars on the equation of state of dense matter and structure of compact stars (CSs) are explored within the covariant density functional theory and confronted with the data on tidal deformability (TD) extracted from the GW170817 event. We show that the presence of $\Delta$ isobars substantially softens the tension between the predictions of the hypernuclear density functionals and the inference from the observations of relatively small radius and small TD of canonical mass CSs. The TDs deduced from GW170817 are compatible with the existence of hypernuclear CSs containing an admixture of $\Delta$ isobars. We thus argue that the GW170817 event is consistent with a merger of a binary CS system having both strangeness (hyperons) and $\Delta$ isobars in the stellar core., Comment: 5 pages, 4 figures, 1 table, matches published version

The occurrence of the bubble-like structure has been studied, in the light of pseudospin degeneracy, within the relativistic Hartree-Fock-Bogoliubov (RHFB) theory. It is concluded that the charge/neutron bubble-like structure is predicted to occur in the mirror system of {$^{34}\mathrm{Si},\phantom{\rule{0.16em}{0ex}}^{34}\mathrm{Ca}$} commonly by the selected Lagrangians, due to the persistence of $Z(N)=14$ subshell gaps above which the $\ensuremath{\pi}(\ensuremath{\nu})2{s}_{1/2}$ states are not occupied. However, for the popular candidate $^{46}\mathrm{Ar}$, the RHFB Lagrangian PKA1 does not support the occurrence of the bubble-like structure in the charge (proton) density profiles, due to the almost degenerate pseudospin doublet ${\ensuremath{\pi}2{s}_{1/2},\ensuremath{\pi}1{d}_{3/2}}$ and coherent pairing effects. The formation of a semibubble in heavy nuclei is less possible as a result of small pseudospin-orbit (PSO) splitting, while it tends to appear at $Z=120$ superheavy systems which coincides with large PSO splitting of the doublet ${\ensuremath{\pi}3{p}_{3/2},\ensuremath{\pi}2{f}_{5/2}}$ and couples with significant shell effects. Pairing correlations, which can work against bubble formation, significantly affect the PSO splitting. Furthermore, we found that the influence on semibubble formation due to different types of pairing interactions is negligible. The quenching of the spin-orbit splitting in the $p$ orbit has been also stressed, and it may be considered the hallmark for semibubble nuclei.