bluuebunny/crossref_metadata_2025_split huggingface dataset:
Far-ultraviolet investigation into the galactic globular cluster M30 (NGC 7099) – II. Potential X-ray counterparts and variable sources
Authors: Mansfield Santana , Dieball Andrea , Kroupa Pavel , Knigge Christian , Zurek David R , Shara Michael , Long Knox S 
Published: April 2022

ABSTRACT
We present a far-ultraviolet (FUV) study of the globular cluster M30 (NGC 7099). The images were obtained using the Advanced Camera for Surveys (ACS/SBC, F150LP, FUV) and the Wide Field Planetary Camera 2 (WFPC2; F300W, UV) on board the Hubble Space Telescope (HST). We compare the catalogue of FUV objects to 10 known X-ray sources and find six confident matches of two cataclysmic variables (CVs), one RS CVn, one red giant with strong FUV emission, and two sources only detected in the FUV. We also searched for variable sources in our data set and found a total of seven blue stragglers (BSs), four horizontal branch (HB) stars, five red giant branch stars, 28 main-sequence stars, and four gap objects that demonstrated variability. One BS star is a known W-UMa contact binary, one of the gap objects is a known CV identified in this work to be a dwarf nova, and the three other gap sources are weak variables. The periods and positions of two of the variable HB stars match them to two previously known RR Lyrae variables of types RRab and RRc.
A systematic search for galaxy protocluster cores at the transition epoch of their star formation activity
Authors: Ando Makoto , Shimasaku Kazuhiro , Momose Rieko , Ito Kei , Sawicki Marcin , Shimakawa Rhythm 
Published: April 2022

ABSTRACT
The redshift of z ∼ 1.5 is the transition epoch of protoclusters (PCs) from the star-forming phase into the quenching phase, and hence an appropriate era to investigate the build up of the quenched population. We define a ‘core’ as the most massive halo in a given PC, where environmental effects are likely to work most effectively, and search for cores at 1 &lt; z &lt; 1.5. We use a photometric redshift catalogue of a wide (effective area of ${\sim}22.2\, \mathrm{deg}^{2}$) and deep ($i\sim 26.8\, \mathrm{mag}$) optical survey with Subaru Hyper-Suprime Cam. Regarding galaxies with log (M*/M⊙) &gt; 11.3 as the central galaxies of PC cores, we estimate their average halo mass by clustering analysis and find it to be log (Mh/M⊙) ∼ 13.7. An expected mass growth by the IllustrisTNG simulation and the observed overdensities around them suggest that the PC cores we find are progenitors of present-day clusters. Classifying our galaxy sample into red and blue galaxies, we calculate the stellar mass function (SMF) and the red galaxy fraction. The SMFs in the PC cores are more-top heavy than field, implying early high-mass galaxy formation and disruption of low-mass galaxies. We also find that the red fraction increases with stellar mass, consistent with stellar mass dependent environmental quenching recently found at z &gt; 1. Interestingly, although the cores with red and blue centrals have similar halo masses, only those with red centrals show a significant red fraction excess compared to the field, suggesting a conformity effect. Some observational features of PC cores may imply that the conformity is caused by assembly bias.
Observational constraints on the deceleration parameter in a tilted universe
Authors: Asvesta Kerkyra , Kazantzidis Lavrentios , Perivolaropoulos Leandros , Tsagas Christos G 
Published: April 2022

ABSTRACT
We study a parametrization of the deceleration parameter in a tilted universe, namely a cosmological model equipped with two families of observers. The first family follows the smooth Hubble flow, while the second is the real observers residing in a typical galaxy inside a bulk flow and moving relative to the smooth Hubble expansion with finite peculiar velocity. We use the compilation of Type Ia supernovae (SNe Ia) data, as described in the Pantheon data set, to find the quality of fit to the data and study the redshift evolution of the deceleration parameter. In so doing, we consider two alternative scenarios, assuming that the bulk-flow observers live in the ΛCDM and in the Einstein-de Sitter universe. We show that a tilted Einstein-de Sitter model can reproduce the recent acceleration history of the universe, without the need of a cosmological constant or dark energy, by simply taking into account linear effects of peculiar motions. By means of a Markov chain Monte Carlo (MCMC) method, we also constrain the magnitude and the uncertainties of the parameters of the two models. From our statistical analysis, we find that the tilted Einstein-de Sitter model, equipped with one or two additional parameters that describe the assumed large-scale velocity flows, performs similar to the standard ΛCDM paradigm in the context of model selection criteria (Akaike information criterion and Bayesian information criterion).
Jets in common envelopes: a low-mass main-sequence star in a red giant
Authors: López-Cámara Diego , De Colle Fabio , Moreno Méndez Enrique , Shiber Sagiv , Iaconi Roberto 
Published: April 2022

ABSTRACTWe present small-scale 3D hydrodynamical simulations of the evolution of a 0.3 M⊙ main-sequence (MS) star that launches two perpendicular jets within the envelope of a 0.88 M⊙ red giant (RG). Based on previous large-scale simulations, we study the dynamics of the jets either when the secondary star is grazing, when it has plunged-in, or when it is well within the envelope of the RG (in each stage for ∼11 d). The dynamics of the jets through the common envelope (CE) depend on the conditions of the environment as well as on their powering. In the grazing stage and the commencement of the plunge self-regulated jets need higher efficiencies to break out of the envelope of the RG. Deep inside the CE, on the time-scales simulated, jets are choked independently of whether they are self-regulated or constantly powered. Jets able to break out of the envelope of the RG in large-scale simulations, are choked in our small-scale simulations. The accreted angular momentum on to the secondary star is not large enough to form a disc. The mass accretion on to the MS star is 1–10 per cent of the Bondi–Hoyle–Littleton rate (∼10−3–10−1 M⊙ yr−1). High-luminosity emission, from X-rays to ultraviolet and optical, is expected if the jets break out of the CE. Our simulations illustrate the need for inclusion of more realistic accretion and jet models in the dynamical evolution of the CEs.
Probing computational methodologies in predicting mid-infrared spectra for large polycyclic aromatic hydrocarbons
Authors: Kerkeni B , García-Bernete I , Rigopoulou D , Tew D P , Roche P F , Clary D C 
Published: April 2022

ABSTRACT
We extend the prediction of vibrational spectra to large sized polycyclic aromatic hydrocarbon (PAH) molecules comprising up to ∼1500 carbon atoms by evaluating the efficiency of several computational chemistry methodologies. We employ classical mechanics methods (Amber and Gaff) with improved atomic point charges, semi-empirical (PM3, and density functional tight binding), and density functional theory (B3LYP) and conduct global optimizations and frequency calculations in order to investigate the impact of PAH size on the vibrational band positions. We primarily focus on the following mid-infrared emission bands 3.3, 6.2, 7.7, 8.6, 11.3, 12.7, and 17.0 μm. We developed a general Frequency Scaling Function ($\mathcal {FSF}$) to shift the bands and to provide a systematic comparison versus the three methods for each PAH. We first validate this procedure on IR scaled spectra from the NASA Ames PAH Database, and extend it to new large PAHs. We show that when the $\mathcal {FSF}$ is applied to the Amber and Gaff IR spectra, an agreement between the normal mode peak positions with those inferred from the B3LYP/4-31G model chemistry is achieved. As calculations become time intensive for large sized molecules Nc &gt; 450, this proposed methodology has advantages. The $\mathcal {FSF}$ has enabled extending the investigations to large PAHs where we clearly see the emergence of the 17.0 μm feature, and the weakening of the 3.3 μm one. We finally investigate the trends in the 3.3 μm/17.0 μm PAH band ratio as a function of PAH size and its response following the exposure to fields of varying radiation intensities.
Stellar and black hole assembly inz&lt; 0.3 infrared-luminous mergers: intermittent starbursts versus super-Eddington accretion
Authors: Farrah Duncan , Efstathiou Andreas , Afonso Jose , Bernard-Salas Jeronimo , Cairns Joe , Clements David L , Croker Kevin , Hatziminaoglou Evanthia , Joyce Maya , Lacy Mark , Lebouteiller Vianney , Lieblich Alix , Lonsdale Carol , Oliver Seb , Pearson Chris , Petty Sara , Pitchford Lura K , Rigopoulou Dimitra , Rowan-Robinson Michael , Runburg Jack , Spoon Henrik , Verma Aprajita , Wang Lingyu 
Published: April 2022

ABSTRACTWe study stellar and black hole mass assembly in a sample of 42 infrared-luminous galaxy mergers at z &lt; 0.3 by combining results from radiative transfer modelling with archival measures of molecular gas and black hole mass. The ratios of stellar mass, molecular gas mass, and black hole mass to each other are consistent with those of massive gas-rich galaxies at z &lt; 0.3. The advanced mergers may show increased black hole mass to stellar mass ratios, consistent with the transition from active galactic nucleus (AGN) to ellipticals and implying substantial black hole mass growth over the course of the merger. Star formation rates are enhanced relative to the local main sequence, by factors of ∼100 in the starburst and ∼1.8 in the host, respectively. The starburst star formation rates appear distinct to star formation in the main sequence at all redshifts up to at least z ∼ 5. Starbursts may prefer late-stage mergers, but are observed at any merger stage. We do not find evidence that the starbursts in these low-redshift systems substantially increase the total stellar mass, with a soft upper limit on the stellar mass increase from starburst activity of about a factor of two. In contrast, 12 objects show evidence for super-Eddington accretion, associated with late-stage mergers, suggesting that many AGN in infrared-luminous mergers go through a super-Eddington phase. The super-Eddington phase may increase black hole mass by up to an order of magnitude at an accretion efficiency of $42\pm 33{{\ \rm per\ cent}}$ over a period of 44 ± 22 Myr. Our results imply that super-Eddington accretion is an important black hole growth channel in infrared-luminous galaxies at all redshifts.
Species-dependent solar rotation effects on the Martian ionosphere
Authors: Wu S-Q , Wu X-S , Cui J , Yao Z-H , Cao Y-T , Lu H-Y , He F , Li L , Wei Y , Cao J-B 
Published: April 2022

ABSTRACT
Atmospheric escape is a central issue in understanding how Mars lost the habitability and it is critically controlled by the link between the atmosphere and the interplanetary space, i.e. the ionosphere. The predominant driver of the Martian ionospheric variability is the solar extreme ultraviolet radiation. To date, how the ionospheric electrons respond to this radiation has been well investigated, but the responses of various ion species are to be understood. Based on a multi-instrument data set from the Mars Atmosphere and Volatile Evolution, we report direct observations of quasi-periodical variations of photoelectrons and ions, with a common period of ≈27.2 d and almost in exact phase with the solar rotation. These diverse variations present remarkably different amplitudes. The ion density variation has a much larger amplitude than the solar flux variation and the electron density variation has a smaller amplitude. For comparison, the amplitude of the photoelectron intensity variation is nearly identical to that of the solar flux variation. The species-dependent solar rotation effects provide a good diagnostic of the upper atmospheric and ionospheric chemistry, urging reconsiderations of the solar-driven composition and variability of any planetary ionosphere.
A standard siren cosmological measurement from the potential GW190521 electromagnetic counterpart ZTF19abanrhr
Authors: Chen Hsin-Yu , Haster Carl-Johan , Vitale Salvatore , Farr Will M , Isi Maximiliano 
Published: April 2022

ABSTRACT
The identification of the electromagnetic (EM) counterpart candidate ZTF19abanrhr to the binary black hole merger GW190521 opens the possibility to infer cosmological parameters from this standard siren with a uniquely identified host galaxy. The distant merger allows for cosmological inference beyond the Hubble constant. Here, we show that the three-dimensional spatial location of ZTF19abanrhr calculated from the EM data remains consistent with the latest sky localization of GW190521 provided by the LIGO-Virgo Collaboration. If ZTF19abanrhr is associated with the GW190521 merger, and assuming a flat wCDM model, we find that $H_0=48^{+23}_{-10}\, \mathrm{km} \, \mathrm{s}^{-1}\, \mathrm{Mpc}^{-1}$, $\Omega _m=0.35^{+0.41}_{-0.26}$, and $w_0=-1.31^{+0.61}_{-0.48}$ (median and $68{{\ \rm per\ cent}}$ credible interval). If we use the Hubble constant value inferred from another gravitational-wave event, GW170817, as a prior for our analysis, together with assumption of a flat ΛCDM and the model-independent constraint on the physical matter density ωm from Planck, we find $H_0=68.9^{+8.7}_{-6.0}\, \mathrm{km} \, \mathrm{s}^{-1}\, \mathrm{Mpc}^{-1}$.
Early evolution of a newborn magnetar with strong precession motion in GRB 180620A
Authors: Zou Le , Liang En-Wei 
Published: April 2022

ABSTRACT
The observed early X-ray plateau in the afterglow lightcurves of some gamma-ray bursts (GRBs) is attributed to the dipole radiations (DRs) of a newborn magnetar. A quasi-periodic oscillation (QPO) signal in the plateau would be strong evidence of the magnetar precession motion. By making a time-frequency domain analysis for the X-ray afterglow lightcurve of GRB 180620A, we find a QPO signal of ∼650 s in its early X-ray plateau. We fit the lightcurve with a magnetar precession model by adopting the Markov chain Monte Carlo algorithm. The observed lightcurve and the QPO signal are well represented with our model. The derived magnetic field strength of the magnetar is $B_{\rm p}= (1.02^{+0.59}_{-0.61})\times 10^{15}$ G. It rapidly spins down with angular velocity evolving as Ωs ∝ (1 + t/τsd)−0.96, where τsd = 9430 s. Its precession velocity evolution is even faster than Ωs, i.e. Ωp ∝ (1 + t/τp)−2.18 ± 0.11, where τp = 2239 ± 206 s. The inferred braking index is n = 2.04. We argue that the extra energy loss via the magnetospheric processes results in its rapid spin-down, low braking index, and strong precession motion of the magnetar.
Disentangling Signatures of Selection Before and After European Colonization in Latin Americans
Authors: Mendoza-Revilla Javier , Chacón-Duque J. Camilo , Fuentes-Guajardo Macarena , Ormond Louise , Wang Ke , Hurtado Malena , Villegas Valeria , Granja Vanessa , Acuña-Alonzo Victor , Jaramillo Claudia , Arias William , Barquera Rodrigo , Gómez-Valdés Jorge , Villamil-Ramírez Hugo , Silva de Cerqueira Caio C. , Badillo Rivera Keyla M. , Nieves-Colón Maria A. , Gignoux Christopher R. , Wojcik Genevieve L. , Moreno-Estrada Andrés , Hünemeier Tábita , Ramallo Virginia , Schuler-Faccini Lavinia , Gonzalez-José Rolando , Bortolini Maria-Cátira , Canizales-Quinteros Samuel , Gallo Carla , Poletti Giovanni , Bedoya Gabriel , Rothhammer Francisco , Balding David , Fumagalli Matteo , Adhikari Kaustubh , Ruiz-Linares Andrés , Hellenthal Garrett 
Published: April 2022

AbstractThroughout human evolutionary history, large-scale migrations have led to intermixing (i.e., admixture) between previously separated human groups. Although classical and recent work have shown that studying admixture can yield novel historical insights, the extent to which this process contributed to adaptation remains underexplored. Here, we introduce a novel statistical model, specific to admixed populations, that identifies loci under selection while determining whether the selection likely occurred post-admixture or prior to admixture in one of the ancestral source populations. Through extensive simulations, we show that this method is able to detect selection, even in recently formed admixed populations, and to accurately differentiate between selection occurring in the ancestral or admixed population. We apply this method to genome-wide SNP data of ∼4,000 individuals in five admixed Latin American cohorts from Brazil, Chile, Colombia, Mexico, and Peru. Our approach replicates previous reports of selection in the human leukocyte antigen region that are consistent with selection post-admixture. We also report novel signals of selection in genomic regions spanning 47 genes, reinforcing many of these signals with an alternative, commonly used local-ancestry-inference approach. These signals include several genes involved in immunity, which may reflect responses to endemic pathogens of the Americas and to the challenge of infectious disease brought by European contact. In addition, some of the strongest signals inferred to be under selection in the Native American ancestral groups of modern Latin Americans overlap with genes implicated in energy metabolism phenotypes, plausibly reflecting adaptations to novel dietary sources available in the Americas.
Rates of Mutations and Transcript Errors in the Foodborne PathogenSalmonella entericasubsp.enterica
Authors: Pan Jiao , Li Weiyi , Ni Jiahao , Wu Kun , Konigsberg Iain , Rivera Caitlyn E. , Tincher Clayton , Gregory Colin , Zhou Xia , Doak Thomas G. , Lee Heewook , Wang Yan , Gao Xiang , Lynch Michael , Long Hongan 
Published: April 2022

AbstractBecause errors at the DNA level power pathogen evolution, a systematic understanding of the rate and molecular spectra of mutations could guide the avoidance and treatment of infectious diseases. We thus accumulated tens of thousands of spontaneous mutations in 768 repeatedly bottlenecked lineages of 18 strains from various geographical sites, temporal spread, and genetic backgrounds. Entailing over ∼1.36 million generations, the resultant data yield an average mutation rate of ∼0.0005 per genome per generation, with a significant within-species variation. This is one of the lowest bacterial mutation rates reported, giving direct support for a high genome stability in this pathogen resulting from high DNA-mismatch-repair efficiency and replication-machinery fidelity. Pathogenicity genes do not exhibit an accelerated mutation rate, and thus, elevated mutation rates may not be the major determinant for the diversification of toxin and secretion systems. Intriguingly, a low error rate at the transcript level is not observed, suggesting distinct fidelity of the replication and transcription machinery. This study urges more attention on the most basic evolutionary processes of even the best-known human pathogens and deepens the understanding of their genome evolution.
Lifestyle Transitions in Fusarioid Fungi are Frequent and Lack Clear Genomic Signatures
Authors: Hill Rowena , Buggs Richard J.A. , Vu Dang Toan , Gaya Ester 
Published: April 2022

AbstractThe fungal genus Fusarium (Ascomycota) includes well-known plant pathogens that are implicated in diseases worldwide, and many of which have been genome sequenced. The genus also encompasses other diverse lifestyles, including species found ubiquitously as asymptomatic-plant inhabitants (endophytes). Here, we produced structurally annotated genome assemblies for five endophytic Fusarium strains, including the first whole-genome data for Fusarium chuoi. Phylogenomic reconstruction of Fusarium and closely related genera revealed multiple and frequent lifestyle transitions, the major exception being a monophyletic clade of mutualist insect symbionts. Differential codon usage bias and increased codon optimisation separated Fusarium sensu stricto from allied genera. We performed computational prediction of candidate secreted effector proteins (CSEPs) and carbohydrate-active enzymes (CAZymes)—both likely to be involved in the host–fungal interaction—and sought evidence that their frequencies could predict lifestyle. However, phylogenetic distance described gene variance better than lifestyle did. There was no significant difference in CSEP, CAZyme, or gene repertoires between phytopathogenic and endophytic strains, although we did find some evidence that gene copy number variation may be contributing to pathogenicity. Large numbers of accessory CSEPs (i.e., present in more than one taxon but not all) and a comparatively low number of strain-specific CSEPs suggested there is a limited specialisation among plant associated Fusarium species. We also found half of the core genes to be under positive selection and identified specific CSEPs and CAZymes predicted to be positively selected on certain lineages. Our results depict fusarioid fungi as prolific generalists and highlight the difficulty in predicting pathogenic potential in the group.
DNA damage in peripheral blood lymphocytes of severely ill COVID-19 patients in relation to inflammatory markers and parameters of hemostasis
Authors: Mihaljevic Olgica , Zivancevic-Simonovic Snezana , Cupurdija Vojislav , Marinkovic Milos , Tubic Vukajlovic Jovana , Markovic Aleksandra , Stanojevic-Pirkovic Marijana , Milosevic-Djordjevic Olivera 
Published: April 2022

Abstract
Bearing in the mind that a variety of agents can contribute to genome instability, including viral infections, the aim of this study was to analyze DNA damage in hospitalized COVID-19 patients and its relationship with certain laboratory parameters. The potential impact of applied therapy and chest X-rays on DNA damage was also estimated. The study population included 24 severely COVID-19 patients and 15 healthy control subjects. The level of DNA damage was measured as genetic damage index (GDI) by comet assay. The standard laboratory methods and certified enzymatic reagents for the appropriate autoanalyzers were performed for the determination of the biochemical and hematological parameters. COVID-19 patients had significantly higher level of DNA damage compared with control subjects. The absolute number of neutrophil leukocytes was statistically higher, while the absolute number of lymphocytes was statistically lower in COVID-19 patients than in healthy controls. The analysis of the relationship between DNA damage and laboratory parameters indicated that GDI was positively correlated with interleukin 6 (IL-6) concentration and negatively with platelet count in COVID-19 patients. The level of DNA damage was slightly higher in female patients, in whom it was demonstrated a positive correlation of GDI with C-reactive protein (CRP) and procalcitonin. Likewise, there was a negative relationship of GDI and platelet count, and positive relationship of GDI and activated partial thromboplastin time (aPTT) in female population. The applied therapy (antibiotics, corticosteroid, anticoagulant, and antiviral therapy) as well as chest X rays has been shown to have genotoxic potential. The level of DNA damage significantly corresponds to the inflammatory markers and parameters of hemostasis in COVID-19 patients. In conclusion, inflammation, smoking habit, applied therapy, and chest X rays contribute to a higher level of DNA damage in COVID-19 patients.