bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bootstrap Inference for Group Factor Models
Authors: Gonçalves Sílvia , Koh Julia , Perron Benoit 
Published: November 2024

Abstract
Andreou et al. (2019) have proposed a test for common factors based on canonical correlations between factors estimated separately from each group. We propose a simple bootstrap test that avoids the need to estimate the bias and variance of the canonical correlations explicitly and provide high-level conditions for its validity. We verify these conditions for a wild bootstrap scheme similar to the one proposed in Gonçalves and Perron (2014). Simulation experiments show that this bootstrap approach leads to null rejection rates closer to the nominal level in all of our designs compared to the asymptotic framework.
Graph-Based Methods for Forecasting Realized Covariances
Authors: Zhang Chao , Pu Xingyue , Cucuringu Mihai , Dong Xiaowen 
Published: November 2024

Abstract
We forecast the realized covariance matrix of asset returns in the U.S. equity market by exploiting the predictive information of graphs in volatility and correlation. Specifically, we augment the Heterogeneous Autoregressive model via neighborhood aggregation on these graphs. Our proposed method allows for the modeling of interdependence in volatility (also known as spillover effect) and correlation, while maintaining parsimony and interpretability. We explore various graph construction methods, including sector membership and graphical LASSO (for modeling volatility), and line graph (for modeling correlation). The results generally suggest that the augmented model incorporating graph information yields both statistically and economically significant improvements for out-of-sample performance over the traditional models. Such improvements remain significant over horizons up to 1 month ahead, but decay in time. The robustness tests demonstrate that the forecast improvements are obtained consistently over the different out-of-sample sub-periods and are insensitive to measurement errors of volatilities.
The afterlife of ISDS awards: post-award settlements and the limits of transparency reforms
Authors: Chernykh Yuliya , Sattorova Mavluda 
Published: November 2024

Abstract
Post-award settlements in investor–state dispute settlement (ISDS) remain largely unstudied. One of the reasons for this gap in knowledge is the lack of transparency in the post-award phase of the relationship between investors and host states. The primary objective of this article is to use novel empirical data to explore the transparency gaps and absences in the post-award phase of ISDS. We seek to challenge the prevailing notions of finality of ISDS awards and highlight the need to re-think the end goals of transparency considering the significant public policy implications post-award agreements may engender. The veil of secrecy that continues to shroud the world of post-award settlements raises a number of issues that go to the heart of the ongoing debate about the workings of ISDS, its legitimacy and the role of openness and accountability therein.
Impact of probiotic Bacillus sp. dietary supplementation on pancreatic and intestinal activities in seabream Sparus aurata
Authors: Yıldırım Şükrü , Suzer Cüneyt , Fırat Kürşat , Saka Şahin , Hekimoğlu Müge , Çoban Deniz , Korkut Ali Yıldırım , Köse İbrahim , Antepli Onurkan , Gökvardar Alize , Perçin Fatih 
Published: November 2024

Abstract
The main objective of this study was to investigate the effects of commercial probiotic Bacillus sp. supplementation on seabream Sparus aurata larviculture under culture conditions. In this context, Bacillus was supplemented via rotifer feeding and water and its effects on pancreatic and intestinal enzyme activities as well as aquaculture parameters were evaluated during early life development. In the experimental group, as probiotic three Bacillus sp. spores were introduced via rotifer and larval culture tanks, while the larvae in control group did not feed any probiotic supplementation. At the end of the experiment on 40 days after hatching, the probiotic-supplemented group exhibited better growth performance and there were statistically differences in between groups of probiotic-treated and control regarding growth parameters (P &lt; 0.01), despite insignificant survival rate (P &gt; 0.05). In terms of enzymatic expressions, S. aurata larvae receiving probiotic supplementation through rotifers demonstrated noteworthy (P &lt; 0.05) enhancements in specific activities of pancreatic and intestinal enzymes, except for amylase (P &gt; 0.05), when compared to the control group. It is concluded that the administration of Bacillus sp. as probiotic bacteria through rotifer supplementation and water intake demonstrates significant positive impacts on both growth parameters and specific activities of main pancreatic and intestinal enzymes of seabream larvae.
Molecular characterization of Staphylococcus aureus from nasal samples of healthy pet cats
Authors: Bezzi Amel , Antri Kenza , Bachtarzi Mohamed Azzedine , Martins-Simoes Patricia , Youenou Benjamin , Gourari Samir , Nateche Farida , Tristan Anne 
Published: November 2024

Abstract
The objective of this study was to characterize Staphylococcus aureus isolates recovered from the nasal samples of healthy pet cats in Algiers province. A total of 138 nasal swabs were collected. Antimicrobial susceptibility was conducted using the disk-diffusion method and the VITEK-2 susceptibility system. Whole genome sequencing was performed to identify multiple-locus sequence typing, antimicrobial and virulence genes. Staphylococcus aureus isolates were detected in 23 cats. Among these, 11 were methicillin-resistant S. aureus (MRSA) (one isolate/sample). Three sequence types (ST6, ST5, and ST1) were identified in MRSA, with the predominance of ST6 (n = 7). Seven distinct STs [ST398, ST97, ST15, ST7, ST291, ST5043, and a new ST, (ST9219)] were detected in methicillin-sensitive S. aureus. All MRSA isolates harbored the mecA gene and SCCmec-type-IVa. MRSA exhibited resistance to tetracycline [n = 3/tet(L) and tet(M); n = 1/tet(K)], kanamycin-tobramycin [n = 3/ant(4′)-Ia), amikacin-kanamycin (n = 1/aph(3′)-IIIa], and erythromycin-clindamycin [n = 1/erm(C)]. Seven S. aureus isolates were multidrug resistant. All the isolates were negative for lukS/lukF-PV and tst-1 genes, while 20 isolates were IEC-positive. This study revealed a diversity of genetic lineages in S. aureus strains isolated from nasal samples of pet cats, including multidrug-resistant and toxigenic strains. The presence of IEC-positive S. aureus suggests possible human–animal transmission.
Biochemical characterization of HcrF from Limosilactobacillus fermentum, a NADH-dependent 2-ene reductase with activity on hydroxycinnamic acids
Authors: Gaur Gautam , Gänzle Michael 
Published: November 2024

Abstract
In fermented plant foods, phenolic compounds are metabolized by 2-ene reductases, which reduce double bonds adjacent to an aromatic rings in phytochemicals, including hydroxycinnamic acids, isoflavones, and flavones. Only few 2-ene reductases of lactic acid bacteria were characterized, including the hydrocinnamic reductases HcrB and Par1, and the daidzein reductase of Lactococcus lactis. This study aimed to characterize HcrF, a homologue of HcrB, in Limosilactobacillus fermentum. HcrF was purified after cloning in Escherichia coli and purification by affinity chromatography. HcrF was optimally active at 30°C–40°C and pH 7.0 and required both flavin mononucleotide and nicotinamide adenine dinucleotide as co-factors. Ferulic, caffeic, p-coumaric, and sinapic acids but not trans-cinnamic acids were reduced to dihydro derivatives. The maximum reaction velocity Vmax of HcrF was highest for ferulic acid. On a phylogenetic tree of 2-ene reductases, HcrF clustered most closely with the hydroxycinnamic acid reductase HcrB of Lactiplantibacillus plantarum. The hydroxycinnamic acid reductase Par1 of Furfurilactobacillus milii and flavone or isoflavone reductases were only distantly related to HcrF. In summary, current knowledge does not allow to predict the substrate specificity of 2-ene reductases on the basis of the protein sequence; this study adds HcrF to the short list of enzymes with known substrate specificity.
Eccentric mergers in AGN discs: influence of the supermassive black hole on three-body interactions
Authors: Fabj Gaia , Samsing Johan 
Published: November 2024

ABSTRACT
There are indications that stellar-origin black holes (BHs) are efficiently paired up in binary black holes (BBHs) in active galactic nucleus (AGN) disc environments, which can undergo interactions with single BHs in the disc. Such binary–single interactions can potentially lead to an exceptionally high fraction of gravitational-wave mergers with measurable eccentricity in LIGO/Virgo/KAGRA. We here take the next important step in this line of studies by performing post-Newtonian N-body simulations between migrating BBHs and single BHs set in an AGN disc-like configuration, with a consistent inclusion of the central supermassive black hole (SMBH) in the equations of motion. With this set-up, we study how the fraction of eccentric mergers varies in terms of the initial size of the BBH semimajor axis relative to the Hill sphere, as well as how it depends on the angle between the BBH and the incoming single BH. We find that the fraction of eccentric mergers is still relatively large, even when the interactions are notably influenced by the gravitational field of the nearby SMBH. However, the fraction as a function of the BBH semimajor axis does not follow a smooth functional shape, but instead shows strongly varying features that originate from the underlying phase-space structure. The phase-space further reveals that many of the eccentric mergers are formed through prompt scatterings. Finally, we present the first analytical solution to how the presence of an SMBH in terms of its Hill sphere affects the probability for forming eccentric BBH mergers through chaotic three-body interactions.
Analysing the dynamics of the Kepler-90 planetary system
Authors: Gaslac Gallardo D M , Giuliatti Winter S M , Winter O , Callegari N , Muñoz-Gutiérrez M A 
Published: November 2024

ABSTRACT
Kepler-90 system has a set of eight planets in a hierarchical structure. In this work, we used frequency analysis to study several Kepler-90 analogues to analyse in detail how the values of the eccentricity of each planet can alter the stability of the system. The system was formed by the star and eight planets for three different intervals of eccentricity ($e$). Our results show that for the first and second intervals, all the systems are stable. However, no set of Kepler-90 systems with large values of $e$ survived up to $10^5$ orbits of Kepler-90h. In the low-eccentricity interval, planets Kepler-90b and Kepler-90c were found to be in a 5:4 mean motion resonance, and the pair Kepler-90g and Kepler-90h in a 3:2 mean motion resonance, although these two pairs are in resonance in different Kepler-90 analogues. In the medium-eccentricity interval, only the pair Kepler-90g and Kepler-90h is in resonance. Kepler-90b and Kepler-90c are in quasi-resonance 5:4; the critical angle circulates and librates intermittently in different periods of time. The results statistically indicate that these resonances directly affect the most of them. The influence covers a wide range of possibilities: (i) a strong resonant mean motion coupling added to a coupling of the longitude of the pericentres; (ii) just a single resonant argument librating; (iii) intermittent behaviour, interleaving libration, and circulation of the resonant arguments; and (iv) the quasi-resonant influence due to the near commensurability.
Reactivity of chondritic meteorites under H2-rich atmospheres: formation of H2S
Authors: Cabedo V , Pareras G , Allitt J , Rimola A , Llorca J , Yiu H H P , McCoustra M R S 
Published: November 2024

ABSTRACT
Current models of chemical evolution during star and planetary formation rely on the presence of dust grains to act as a third body. However, they generally ignore the reactivity of the dust grains themselves. Dust grains present in the protoplanetary phase will evolve as the Solar system forms and, after protoplanets have appeared, they will be constantly delivered to their surfaces in the form of large aggregates or meteorites. Chondritic meteorites are mostly unaltered samples of the dust present in the first stages of the Solar system formation, which still arrive nowadays to the surface of Earth and allow us to study the properties of the materials forming the early Solar system. These materials contain, amongst others, transition metals that can potentially act as catalysts, as well as other phases that can potentially react in different astrophysical conditions, such as FeS. In this work, we present the reactivity of chondritic meteorites under H$_{2}$-rich atmospheres, particularly towards the reduction of FeS for the formation of H$_{2}$S and metallic Fe during the early phases of the planetary formation. We present the obtained results on the reaction rates and the percentage of FeS available to react in the materials. Additionally, we include a computational study of the reaction mechanism and the energetics. Finally, we discuss the implications of an early formation of H$_{2}$S in planetary surfaces.
From particles to pixels: how many particles do I really need to construct stellar kinematic mock observational measurements?
Authors: Harborne K E , Lagos C del P , Croom S M , van de Sande J , Ludlow A , Remus R S , Kimmig L C , Power C 
Published: November 2024

ABSTRACT
This work considers the impact of resolution in the construction of mock observations of simulated galaxies. In particular, when building mock integral field spectroscopic observations from galaxy formation models in cosmological simulations, we investigate the possible systematics that may arise given the assumption that all galaxies above some stellar mass limit will provide unbiased and meaningful observable stellar kinematics. We build a catalogue of N-body simulations to sample the range of stellar particle resolutions within the EagleRef0050N0752 simulation box and examine how their observable kinematics vary relative to a higher-resolution N-body control. We use these models to compile a table of the minimum number of particles-per-pixel to reach a given uncertainty in the fitted line-of-sight velocity distribution parameters. Further, we introduce a Voronoi-binning module to the mock observation code, SimSpin, in order to meet these minimum numbers. Using Eagle, we show the impact of this shot noise on the observed spin–ellipticity plane and the recovery of this space when observations are binned with increasing numbers of particles. In conclusion, we advise binning mock images to meet at least 200 particles-per-pixel to avoid systematically under-estimating the velocity dispersion along a given line-of-sight. We demonstrate that this is important for comparing galaxies extracted from the same simulation, as well as between simulations of varying mass resolution and observations of real galaxies.
The structure of the stellar halo of the Andromeda galaxy explored with the NB515 for Subaru/HSC – I. New insights on the stellar halo up to 120 kpc
Authors: Ogami Itsuki , Tanaka Mikito , Komiyama Yutaka , Chiba Masashi , Guhathakurta Puragra , Kirby Evan N , Wyse Rosemary F G , Filion Carrie , Gilbert Karoline M , Escala Ivanna , Mori Masao , Kirihara Takanobu , Tanaka Masayuki , Ishigaki Miho N , Hayashi Kohei , Lee Myun Gyoon , Sharma Sanjib , Kalirai Jason S , Lupton Robert H 
Published: November 2024

ABSTRACT
We analyse the M31 halo and its substructure within a projected radius of 120 kpc using a combination of Subaru/HSC NB515 and Canada France Hawaii Telescope/MegaCam g and i bands. We succeed in separating M31’s halo stars from foreground contamination with $\sim$90 per cent accuracy by using the surface gravity sensitive NB515 filter. Based on the selected M31 halo stars, we discover three new substructures, which associate with the Giant Southern Stream (GSS) based on their photometric metallicity estimates. We also produce the distance and photometric metallicity estimates for the known substructures. While these quantities for the GSS are reproduced in our study, we find that the north-western stream shows a steeper distance gradient than found in an earlier study, suggesting that it is likely to have formed in an orbit closer to the Milky Way. For two streams in the eastern halo (Stream C and D), we identify distance gradients that had not been resolved. Finally, we investigate the global halo photometric metallicity distribution and surface brightness profile using the NB515-selected halo stars. We find that the surface brightness of the metal-poor and metal-rich halo populations, and the all population can be fitted to a power-law profile with an index of $\alpha =-1.65\pm 0.02$, $-2.82\pm 0.01$, and $-2.44\pm 0.01$, respectively. In contrast to the relative smoothness of the halo profile, its photometric metallicity distribution appears to be spatially non-uniform with non-monotonic trends with radius, suggesting that the halo population had insufficient time to dynamically homogenize the accreted populations.
MIGHTEE: the continuum survey Data Release 1
Authors: Hale C L , Heywood I , Jarvis M J , Whittam I H , Best P N , An Fangxia , Bowler R A A , Harrison I , Matthews A , Smith D J B , Taylor A R , Vaccari M 
Published: November 2024

ABSTRACT
The MeerKAT International GHz Tiered Extragalactic Exploration Survey (MIGHTEE) is one of the large survey projects using the MeerKAT telescope, covering four fields that have a wealth of ancillary data available. We present Data Release 1 of the MIGHTEE continuum survey, releasing total intensity images and catalogues over $\sim$20 deg$^2$, across three fields at $\sim$1.2–1.3 GHz. This includes 4.2 deg$^2$ over the Cosmic Evolution Survey (COSMOS) field, 14.4 deg$^2$ over the XMM Large-Scale Structure (XMM-LSS) field and deeper imaging over 1.5 deg$^2$ of the Extended Chandra Deep Field South (CDFS). We release images at both a lower resolution (7–9 arcsec) and higher resolution ($\sim 5$ arcsec). These images have central rms sensitivities of $\sim 1.3-$2.7 $\mu$Jy beam$^{-1}$ ($\sim 1.2-$3.6 $\mu$Jy beam$^{-1}$) in the lower (higher) resolution images, respectively. We also release catalogues comprised of $\sim$144 000 ($\sim$114 000) sources using the lower (higher) resolution images. We compare the astrometry and flux-density calibration with the Early Science data in the COSMOS and XMM-LSS fields and previous radio observations in the CDFS field, finding broad agreement. Furthermore, we extend the source counts at the $\sim$10 $\mu$Jy level to these larger areas ($\sim 20$ deg$^2$) and, using the areal coverage of MIGHTEE we measure the sample variance for differing areas of sky. We find a typical sample variance of 10 –20 per cent for 0.3 and 0.5 deg2 subregions at $S_{1.4} \le 200$$\mu$Jy, which increases at brighter flux densities, given the lower source density and expected higher galaxy bias for these sources.
The cooler past of the intracluster medium in TNG-cluster
Authors: Rohr Eric , Pillepich Annalisa , Nelson Dylan , Ayromlou Mohammadreza , Péroux Céline , Zinger Elad 
Published: November 2024

ABSTRACT
The intracluster medium (ICM) today is comprised largely of hot gas with clouds of cooler gas of unknown origin and lifespan. We analyse the evolution of cool gas (temperatures $\lesssim 10^{4.5}$ K) in the ICM of 352 galaxy clusters from the TNG-Cluster simulations, with present-day mass $\sim 10^{14.3-15.4}\, {\rm M}_\odot$. We follow the main progenitors of these clusters over the past $\sim 13$ billion years (since $z\lesssim 7$) and find that, according to TNG-Cluster, the cool ICM mass increases with redshift at fixed cluster mass, implying that this cooler past of the ICM is due to more than just halo growth. The cool cluster gas at $z\lesssim 0.5$ is mostly located in and around satellite galaxies, while at $z\gtrsim 2$ cool gas can also accrete via filaments from the intergalactic medium. Lower-mass and higher-redshift clusters are more susceptible to cooling. The cool ICM mass correlates with the number of gaseous satellites and inversely with the central supermassive black hole (SMBH) mass. The average number of gaseous satellites decreases since $z=2$, correlating with the decline in the cool ICM mass over cosmic time, suggesting a link between the two. Concurrently, kinetic SMBH feedback shifts the ICM temperature distribution, decreasing the cool ICM mass inside–out. At $z\approx 0.5$, the predicted Mg ii column densities are in the ballpark of recent observations, where satellites and other haloes contribute significantly to the total Mg ii column density. Suggestively, a non-negligible amount of the ICM cool gas forms stars in situ at early times, reaching $\sim 10^{2}\, {\rm M}_\odot \, {\rm ~yr^{-1}}$ and an H $\alpha$ surface brightness of $\sim 10^{-17}\, {\rm ~erg\, s^{-1}\, cm^{-2}\, arcsec^{-2}}$ at $z\approx 2$, detectable with Euclid and JWST.
Ionizing properties of galaxies in JADES for a stellar mass complete sample: resolving the cosmic ionizing photon budget crisis at the Epoch of Reionization
Authors: Simmonds C , Tacchella S , Hainline K , Johnson B D , Puskás D , Robertson B , Baker W M , Bhatawdekar R , Boyett K , Bunker A J , Cargile P A , Carniani S , Chevallard J , Curti M , Curtis-Lake E , Ji Z , Jones G C , Kumari N , Laseter I , Maiolino R , Maseda M V , Rinaldi P , Stoffers A , Übler H , Villanueva N C , Williams C C , Willott C , Witstok J , Zhu Y 
Published: November 2024

ABSTRACT
We use NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) to study the ionizing properties of a sample of 14 652 galaxies at $3 \le z_{\rm {phot}} \le 9$, 90 per cent complete in stellar mass down to log(M$_{\star }$/[M$_{\odot }])\approx 7.5$. Out of the full sample, 1620 of the galaxies have spectroscopic redshift measurements from the literature. We use the spectral energy distribution fitting code Prospector to fit all available photometry and infer galaxy properties. We find a significantly milder evolution of the ionizing photon production efficiency ($\xi _{\rm {ion}}$) with redshift and UV magnitude than previously reported. Interestingly, we observe two distinct populations in $\xi _{\rm {ion}}$, distinguished by their burstiness (given by SFR$_{10}$/SFR$_{100}$). Both populations show the same evolution with z and M$_{\rm {UV}}$, but have a different $\xi _{\rm {ion}}$ normalization. We convolve the more representative $\log (\xi _{\rm {ion}} (z,\text{M}_{\rm {UV}}))$ relations (accounting for $\sim 97$ % of the sample), with luminosity functions from literature, to place constraints on the cosmic ionizing photon budget. By combining our results, we find that one of our models can match the observational constraints from the Ly $\alpha$ forest at $z\lesssim 6$. We conclude that galaxies with M$_{\rm {UV}}$ between $-16$ and $-20$, adopting a reasonable escape fraction, can produce enough ionizing photons to ionize the Universe, without exceeding the required ionizing photon budget.