bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the dominant role of wind in the quasar feedback mode in the late-stage evolution of massive elliptical galaxies
Authors: Zhu Bocheng , Yuan Feng , Ji Suoqing , Peng Yingjie , Ho Luis C 
Published: September 2023

ABSTRACT
In this paper, we investigate the role of active galactic nucleus (AGN) feedback on the late-stage evolution of elliptical galaxies by performing high-resolution hydrodynamical simulation in the MACER framework. By comparing models that take into account different feedback mechanisms, namely AGN and stellar feedback, we find that AGN feedback is crucial in keeping the black hole in a low accretion state and suppressing the star formation. We then compare the energy from AGN radiation and wind deposited in the galaxy and find that only wind can compensate for the radiative cooling of the gas in the galaxy. Further, we investigate which plays the dominant role, the wind from the cold (quasar) or hot (radio) feedback modes, by examining the cumulative energy output and impact area to which the wind can heat the interstellar medium and suppress star formation. Our results indicate that first, although AGN spends most of its time in hot (radio) mode, the cumulative energy output is dominated by the outburst of the cold (quasar) mode. Second, only the impact area of the cold-mode wind is large enough to heat the gas in the halo, while the hot-mode wind is not. Additionally, the cold-mode wind is capable of sweeping up the material from stellar mass-loss. These results indicate the dominant role of cold-mode wind. The limitations of our model, including the absence of jet feedback, are discussed.
Metal enrichment due to embedded stars in AGN discs
Authors: Huang Jiamu , Lin Douglas N C , Shields Gregory 
Published: September 2023

ABSTRACT
We separately assess elemental abundances in active galactic nuclei's (AGNs) broad and narrow emission line regions (BLR and NLR), based on a critical assessment of published results together with new photoionization models. We find (1) He/H enhancements in some AGN, exceeding what can be explained by normal chemical evolution and confirm, (2) super-solar α abundance, though to a lesser degree than previously reported. We also reaffirm, (3) an N/O ratio consistent with secondary production, (4) solar or slightly sub-solar Fe abundance, and (5) red-shift independent metallicity, in contrast with galactic chemical evolution. We interpret (6) the larger metallicity in the BLR than NRL in terms of an in situ stellar evolution and pollution in AGN discs (SEPAD) model. We attribute (a) the redshift independence to the heavy element pollutants being disposed into the disc and accreted onto the central supermassive black hole (SMBH), (b) the limited He excess to the accretion–wind metabolism of a top-heavy population of evolving massive main sequence stars, (c) the super-solar CNO enrichment to the nuclear synthesis during their post-main-sequence evolution, (d) the large N/O to the byproduct of multiple stellar generations, and (e) the Mg, Si, and Fe to the ejecta of type II supernovae in the disc. These results provide supporting evidence for (f) ongoing self-regulated star formation, (g) adequate stellar luminosity to maintain marginal gravitational stability, (h) prolific production of seeds, and (i) dense coexistence of subsequently grown residual black hole populations in AGN discs.
The cluster initial mass function of the M82 disc super star clusters
Authors: Cuevas-Otahola B , Mayya Y D , Arriaga-Hernández J , Puerari I , Bruzual G 
Published: September 2023

ABSTRACT
The presence of a population of a large number (∼400) of almost coeval (100–300 Myr) super star clusters (SSCs) in the disc of M82 offers an opportunity to construct the Cluster Initial Mass Function (CIMF) from the observed present-day Cluster Mass Function (CMF). We carry out the dynamical and photometric evolution of the CMF assuming that the clusters move in circular orbits under the gravitational potential of the host galaxy using the semi-analytical simulation code Evolve Me a Cluster of StarS. We explore power-law and lognormal functions for the CIMFs, and populate the clusters in the disc assuming uniform, power-law, and exponential radial distribution functions. We find that the observed CMF is best produced by a CIMF that is power law in form with an index of 1.8, for a power-law radial distribution function. More importantly, we establish that the observed turn-over in the present-day CMF is the result of observational incompleteness rather than due to dynamically induced effects, or an intrinsically lognormal CIMF, as was proposed for the fossil starburst region B of this galaxy. Our simulations naturally reproduce the mass–radius relation observed for a sub-sample of M82 SSCs.
Reduction of supernova light curves by vector Gaussian processes
Authors: Kornilov Matwey V , Semenikhin T A , Pruzhinskaya M V 
Published: September 2023

ABSTRACT
Bolometric light curves play an important role in understanding the underlying physics of various astrophysical phenomena, as they allow for a comprehensive modelling of the event and enable comparison between different objects. However, constructing these curves often requires the approximation and extrapolation from multicolour photometric observations. In this study, we introduce vector Gaussian processes as a new method for reduction of supernova light curves. This method enables us to approximate vector functions, even with inhomogeneous time-series data, while considering the correlation between light curves in different passbands. We applied this methodology to a sample of 29 superluminous supernovae (SLSNe) assembled using the Open Supernova Catalog. Their multicolour light curves were approximated using vector Gaussian processes. Subsequently, under the blackbody assumption for the SLSN spectra at each moment of time, we reconstructed the bolometric light curves. The vector Gaussian processes developed in this work are accessible via the python library gp-multistate-kernel on GitHub. Our approach provides an efficient tool for analysing light curve data, opening new possibilities for astrophysical research.
Eliminating polarization leakage effect for neutral hydrogen intensity mapping with deep learning
Authors: Gao Li-Yang , Li Yichao , Ni Shulei , Zhang Xin 
Published: September 2023

ABSTRACT
The neutral hydrogen (H i) intensity mapping (IM) survey is regarded as a promising approach for cosmic large-scale structure studies. A major issue for the H i IM survey is to remove the bright foreground contamination. A key to successfully removing the bright foreground is to well control or eliminate the instrumental effects. In this work, we consider the instrumental effects of polarization leakage and use the U-Net approach, a deep learning-based foreground removal technique, to eliminate the polarization leakage effect. The thermal noise is assumed to be a subdominant factor compared with the polarization leakage for future H i IM surveys and ignored in this analysis. In this method, the principal component analysis (PCA) foreground subtraction is used as a pre-processing step for the U-Net foreground subtraction. Our results show that the additional U-Net processing could either remove the foreground residual after the conservative PCA subtraction or compensate for the signal loss caused by the aggressive PCA pre-processing. Finally, we test the robustness of the U-Net foreground subtraction technique and show that it is still reliable in the case of existing constraint error on H i fluctuation amplitude.
Faint [C i](1–0) emission in z ∼ 3.5 radio galaxies
Authors: Kolwa S , De Breuck C , Vernet J , Wylezalek D , Wang W , Popping G , Man A W S , Harrison C M , Andreani P 
Published: September 2023

ABSTRACT
We present Atacama Large Millimeter/sub-millimeter Array neutral carbon, [${\rm C\, \small {\rm I}}$](1–0), line observations that probe molecular hydrogen gas (H2) within seven radio galaxies at z = 2.9−4.5 surrounded by extended (≳100 kpc) Ly α nebulae. We extract [${\rm C\, \small {\rm I}}$](1–0) emission from the radio-active galactic nuclei (AGNs) host galaxies whose positions are set by near-infrared detections and radio detections of the cores. Additionally, we place constraints on the galaxies’ systemic redshifts via ${\rm He\, \small {\rm II}}$ λ1640 lines seen with the Multi-Unit Spectroscopic Explorer. We detect faint [${\rm C\, \small {\rm I}}$] emission in four out of seven sources. In two of these galaxies, we discover narrow-line emission of full width at half-maximum ≲100 km s−1 that may trace emission from bright kpc-scale gas clouds within the interstellar medium (ISM). In the other two [${\rm C\, \small {\rm I}}$]-detected galaxies, line dispersions range from ∼100−600 km s−1 and may be tracing the rotational component of the cold gas. Overall, the [${\rm C\, \small {\rm I}}$] line luminosities correspond to H2 masses of $M_{\rm H_2,[{\rm C\, \small {\rm I}}]} \simeq (0.5{\!-\!}3) \times 10^{10}$ M⊙ for the detections and $M_{\rm H_2,[{\rm C\, \small {\rm I}}]}\lt 0.65\times 10^{10}$ M⊙ for the [${\rm C\, \small {\rm I}}$] non-detections in three out of seven galaxies within the sample. The molecular gas masses in our sample are relatively low in comparison to previously reported measures for similar galaxies that are $M_{\rm H_2,[{\rm C\, \small {\rm I}}]} \simeq (3{\!-\!}4) \times 10^{10}$ M⊙. Our results imply that the observed faintness in carbon emission is representative of a decline in molecular gas supply from previous star formation epochs and/or a displacement of molecular gas from the ISM due to jet-powered outflows.
Analysis of γ-ray emission above 30 GeV from the LMC pulsar wind nebula N 157B with Fermi-LAT
Authors: Gong Yunlu , Xiao Yifan , Zhou Liancheng , Tian Shiting , Fang Jun 
Published: September 2023

ABSTRACT
N 157B located in the Large Magellanic Cloud is the first pulsar wind nebula detected outside of the Galaxy in γ-rays. In this paper, we analyse the emission above 30 GeV from N 157B using ∼14.3 yr of Fermi-LAT data. The γ-ray spectrum between 30 and 500 GeV is well described by a single power-law function with a photon index of 1.83 ± 0.26, and its integral photon flux is (4.10 ± 0.83) × 10−11 photons cm−2 s−1. We adopt a one-zone leptonic model to investigate whether the multiband non-thermal emission of the target source can be generated by synchrotron radiation and inverse-Compton scattering of the electrons/positrons. Assuming the electrons/positrons in the nebula have a broken power-law spectrum with two breaks, the model can reproduce the observed fluxes in the radio, X-ray, and γ-ray bands. This result indicates that the γ-ray emission from N 157B can be explained by the leptonic process of electrons/positrons via inverse-Compton scattering.
VLBI Observations of a sample of Palomar-Green quasars II: characterizing the parsec-scale radio emission
Authors: Wang Ailing , An Tao , Zhang Yingkang , Cheng Xiaopeng , Ho Luis C , Kellermann Kenneth I , Baan Willem A 
Published: September 2023

ABSTRACT
This study uses multifrequency very long baseline interferometry (VLBI) to study the radio emission from 10 radio-quiet quasars (RQQs) and four radio-loud quasars (RLQs). The diverse morphologies, radio spectra, and brightness temperatures observed in the VLBI images of these RQQs, together with the variability in their GHz spectra and VLBI flux densities, shed light on the origins of their nuclear radio emission. The total radio emission of RQQs appears to originate from non-thermal synchrotron radiation due to a combination of active galactic nuclei and star formation activities. However, our data suggest that the VLBI-detected radio emission from these RQQs is primarily associated with compact jets or corona, with extended emissions such as star formation and large-scale jets being resolved by the high resolution of the VLBI images. Wind emission models are not in complete agreement the VLBI observations. Unlike RLQs, where the parsec-scale radio emission is dominated by a relativistically boosted core, the radio cores of RQQs are either not dominant or are mixed with significant jet emission. RQQs with compact cores or core-jet structures typically have more pronounced variability, with flat or inverted spectra, whereas jet-dominated RQQs have steep spectra and unremarkable variability. Future high-resolution observations of more RQQs could help to determine the fraction of different emission sources and their associated physical mechanisms.
Acute and Long-Term Consequences of Co-opted doublesex on the Development of Mimetic Butterfly Color Patterns
Authors: VanKuren Nicholas W , Doellman Meredith M , Sheikh Sofia I , Palmer Droguett Daniela H , Massardo Darli , Kronforst Marcus R 
Published: September 2023

Abstract
Novel phenotypes are increasingly recognized to have evolved by co-option of conserved genes into new developmental contexts, yet the process by which co-opted genes modify existing developmental programs remains obscure. Here, we provide insight into this process by characterizing the role of co-opted doublesex in butterfly wing color pattern development. dsx is the master regulator of insect sex differentiation but has been co-opted to control the switch between discrete nonmimetic and mimetic patterns in Papilio alphenor and its relatives through the evolution of novel mimetic alleles. We found dynamic spatial and temporal expression pattern differences between mimetic and nonmimetic butterflies throughout wing development. A mimetic color pattern program is switched on by a pulse of dsx expression in early pupal development that causes acute and long-term differential gene expression, particularly in Wnt and Hedgehog signaling pathways. RNAi suggested opposing, novel roles for these pathways in mimetic pattern development. Importantly, Dsx co-option caused Engrailed, a primary target of Hedgehog signaling, to gain a novel expression domain early in pupal wing development that is propagated through mid-pupal development to specify novel mimetic patterns despite becoming decoupled from Dsx expression itself. Altogether, our findings provide multiple views into how co-opted genes can both cause and elicit changes to conserved networks and pathways to result in development of novel, adaptive phenotypes.
Wilson disease–causing mutations in the carboxyl terminus of ATP7B regulates its localization and Golgi exit selectively in the unpolarized cells
Authors: Chakraborty Kaustav , Das Santanu , Pal Anusree , Maji Saptarshi , Rai Bhawana , Gupta Arnab , Bhattacharjee Ashima 
Published: September 2023

Abstract
Mutational inactivation of the P-type Cu-ATPase ATP7B interferes with its cellular functions to varying extent leading to varied cellular phenotypes. Wilson's disease (WD) primarily affects organs composed of polarized/differentiated epithelial cells. Therefore, phenotypic variability might differ depending on the polarization/differentiation of the cells. The present study investigates the intracellular stability and localization of ATP7B harboring WD mutations in both unpolarized/undifferentiated and polarized/differentiated cell-based models. Green fluorescent protein (GFP)-ATP7B harboring the WD causing mutations, N41S, S653Y, R778Q, G1061E, H1069Q, S1423N, S1426I, and T1434M, are included for investigation. The C-terminal WD mutations (S1423N, S1426I, and T1434M), exhibit distinct localization and Cu(I) responsive anterograde and retrograde trafficking in undifferentiated/unpolarized vs. differentiated/polarized cells. While basal localization of the S1423N mutant gets corrected in the differentiated glia, its Cu(I) responsive anterograde and retrograde trafficking behavior is not identical to the wild-type. But localization and trafficking properties are completely rescued for the S1426I and T1434M mutants in the differentiated cells. Comprehensive meta-analysis on the effect of the reported C-terminal mutations on patient phenotype and cultured cells demonstrate discrete regions having distinct effects. While mutations in the proximal C-terminus affect ATP7B stability, the present study shows that the distal region dictates cell-specific Trans Golgi Network (TGN) localization and exit. The localization and export properties are corrected in the differentiated cells, which is a plausible mechanism for the milder phenotype exhibited by these mutations. It highlights the critical role of the C-terminus in cell-specific TGN retention and exit of ATP7B.
The basics of phosphate metabolism
Authors: Wagner Carsten A 
Published: September 2023

ABSTRACT
Phosphorus is an essential mineral that is, in the form of inorganic phosphate (Pi), required for building cell membranes, DNA and RNA molecules, energy metabolism, signal transduction and pH buffering. In bone, Pi is essential for bone stability in the form of apatite. Intestinal absorption of dietary Pi depends on its bioavailability and has two distinct modes of active transcellular and passive paracellular absorption. Active transport is transporter mediated and partly regulated, while passive absorption depends mostly on bioavailability. Renal excretion controls systemic Pi levels, depends on transporters in the proximal tubule and is highly regulated. Deposition and release of Pi into and from soft tissues and bone has to be tightly controlled. The endocrine network coordinating intestinal absorption, renal excretion and bone turnover integrates dietary intake and metabolic requirements with renal excretion and is critical for bone stability and cardiovascular health during states of hypophosphataemia or hyperphosphataemia as evident from inborn or acquired diseases. This review provides an integrated overview of the biology of phosphate and Pi in mammals.
Green synthesis of bifunctional phthalocyanine-porphyrin COFs in water for efficient electrocatalytic CO2 reduction coupled with methanol oxidation
Authors: Zhang Mi , Liao Jia-Peng , Li Run-Han , Sun Sheng-Nan , Lu Meng , Dong Long-Zhang , Huang Pei , Li Shun-Li , Cai Yue-Peng , Lan Ya-Qian 
Published: September 2023

ABSTRACT
Electrocatalytic CO2 reduction (ECR) coupled with organic oxidation is a promising strategy to produce high value-added chemicals and improve energy efficiency. However, achieving the efficient redox coupling reaction is still challenging due to the lack of suitable electrocatalysts. Herein, we designed two bifunctional polyimides-linked covalent organic frameworks (PI-COFs) through assembling phthalocyanine (Pc) and porphyrin (Por) by non-toxic hydrothermal methods in pure water to realize the above catalytic reactions. Due to the high conductivity and well-defined active sites with different chemical environments, NiPc-NiPor COF performs efficient ECR coupled with methanol oxidation reaction (MOR) (Faradaic efficiency of CO (FECO) = 98.12%, partial current densities of CO (jCO) = 6.14 mA cm−2 for ECR, FEHCOOH = 93.75%, jHCOOH = 5.81 mA cm−2 for MOR at low cell voltage (2.1 V) and remarkable long-term stability). Furthermore, experimental evidences and density functional theory (DFT) calculations demonstrate that the ECR process mainly conducts on NiPc unit with the assistance of NiPor, meanwhile, the MOR prefers NiPor conjugating with NiPc. The two units of NiPc-NiPor COF collaboratively promote the coupled oxidation-reduction reaction. For the first time, this work achieves the rational design of bifunctional COFs for coupled heterogeneous catalysis, which opens a new area for crystalline material catalysts.
Genome degradation promotes Salmonella pathoadaptation by remodeling fimbriae-mediated proinflammatory response
Authors: Zhou Xiao , Kang Xiamei , Chen Jiaqi , Song Yan , Jia Chenghao , Teng Lin , Tang Yanting , Jiang Zhijie , Peng Xianqi , Tao Xiaoxi , Xu Yiwei , Huang Linlin , Xu Xuebin , Xu Yaohui , Zhang Tengfei , Yu Shenye , Gong Jiansen , Wang Shaohui , Liu Yuqing , Zhu Guoqiang , Kehrenberg Corinna , Weill François-Xavier , Barrow Paul , Li Yan , Zhao Guoping , Yue Min 
Published: September 2023

ABSTRACT
Understanding changes in pathogen behavior (e.g. increased virulence, a shift in transmission channel) is critical for the public health management of emerging infectious diseases. Genome degradation via gene depletion or inactivation is recognized as a pathoadaptive feature of the pathogen evolving with the host. However, little is known about the exact role of genome degradation in affecting pathogenic behavior, and the underlying molecular detail has yet to be examined. Using large-scale global avian-restricted Salmonella genomes spanning more than a century, we projected the genetic diversity of Salmonella Pullorum (bvSP) by showing increasingly antimicrobial-resistant ST92 prevalent in Chinese flocks. The phylogenomic analysis identified three lineages in bvSP, with an enhancement of virulence in the two recently emerged lineages (L2/L3), as evidenced in chicken and embryo infection assays. Notably, the ancestor L1 lineage resembles the Salmonella serovars with higher metabolic flexibilities and more robust environmental tolerance, indicating stepwise evolutionary trajectories towards avian-restricted lineages. Pan-genome analysis pinpointed fimbrial degradation from a virulent lineage. The later engineered fim-deletion mutant, and all other five fimbrial systems, revealed behavior switching that restricted horizontal fecal–oral transmission but boosted virulence in chicks. By depleting fimbrial appendages, bvSP established persistent replication with less proinflammation in chick macrophages and adopted vertical transovarial transmission, accompanied by ever-increasing intensification in the poultry industry. Together, we uncovered a previously unseen paradigm for remodeling bacterial surface appendages that supplements virulence-enhanced evolution with increased vertical transmission.
Improving error-correcting capability in DNA digital storage via soft-decision decoding
Authors: Ding Lulu , Wu Shigang , Hou Zhihao , Li Alun , Xu Yaping , Feng Hu , Pan Weihua , Ruan Jue 
Published: September 2023

ABSTRACT
Error-correcting codes (ECCs) employed in the state-of-the-art DNA digital storage (DDS) systems suffer from a trade-off between error-correcting capability and the proportion of redundancy. To address this issue, in this study, we introduce soft-decision decoding approach into DDS by proposing a DNA-specific error prediction model and a series of novel strategies. We demonstrate the effectiveness of our approach through a proof-of-concept DDS system based on Reed-Solomon (RS) code, named as Derrick. Derrick shows significant improvement in error-correcting capability without involving additional redundancy in both in vitro and in silico experiments, using various sequencing technologies such as Illumina, PacBio and Oxford Nanopore Technology (ONT). Notably, in vitro experiments using ONT sequencing at a depth of 7× reveal that Derrick, compared with the traditional hard-decision decoding strategy, doubles the error-correcting capability of RS code, decreases the proportion of matrices with decoding-failure by 229-fold, and amplifies the potential maximum storage volume by impressive 32 388-fold. Also, Derrick surpasses ‘state-of-the-art’ DDS systems by comprehensively considering the information density and the minimum sequencing depth required for complete information recovery. Crucially, the soft-decision decoding strategy and key steps of Derrick are generalizable to other ECCs’ decoding algorithms.