bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of a sample of faint Be stars in the exofield of CoRoT
Authors: Zorec J. , Hubert A. M. , Martayan C. , Frémat Y. 
Published: June 2023

Context. The search and interpretation of non-radial pulsations from Be star light curves observed with the CoRoT satellite requires high-quality stellar astrophysical parameters.
Aims. The present work is devoted to the spectroscopic study of a sample of faint Be stars observed by CoRoT in the fourth long run (LRA02).
Methods. The astrophysical parameters were determined from the spectra in the λλ4000–4500 Å wavelength domain observed with the VLT/FLAMES instruments at ESO. Spectra were fitted with models of stellar atmospheres using our GIRFIT package. Spectra obtained in the λλ6400–7200 Å wavelength domain enabled the confirmation or, otherwise, a first identification of Be star candidates.
Results. The apparent parameters (Teff, log g, Vsin i) for a set of 19 B and Be stars were corrected for the effects induced by the rapid rotation. These allowed us to determine: (1) stellar masses that are in agreement with those measured for detached binary systems; (2) spectroscopic distances that agree with the Gaia parallaxes; and (3) centrifugal/gravity equatorial force ratios of ~0.6–0.7, which indicate that our Be stars are subcritical rotators. A study of the Balmer Hα, Hγ and Hδ emission lines produced: (1) extents of the circumstellar disk (CD) emitting regions that agree with the interferometric inferences in other Be stars; (2) R– dependent exponents n(R) = ln[ρ(R)/ρo]/ln(Ro/R) of the CD radial density distributions; and (3) CD base densities ρo similar to those inferred in other recent works.
Conclusions. The Hγ and Hδ emission lines are formed in CD layers close to the central star. These lines produced a different value of the exponent n(R) than assumed for Hα. Further detailed studies of Hγ and Hδ emission lines could reveal the physical properties of regions where the viscous transport of angular momentum to the remaining CD regions is likely to originate from. The subcritical rotation of Be stars suggests that their huge discrete mass-ejections and concomitant non-radial pulsations might have a common origin in stellar envelope regions that become unstable to convection due to rotation. If it is proven that the studied Be stars are products of binary mass transfer phases, the errors induced on the estimated Teff by the presence of stripped sub-dwarf O/B companions are not likely to exceed their present uncertainties.
ExoMDN: Rapid characterization of exoplanet interior structures with mixture density networks
Authors: Baumeister Philipp , Tosi Nicola 
Published: June 2023

Aims.Characterizing the interior structure of exoplanets is essential for understanding their diversity, formation, and evolution. As the interior of exoplanets is inaccessible to observations, an inverse problem must be solved, where numerical structure models need to conform to observable parameters such as mass and radius. This is a highly degenerate problem whose solution often relies on computationally expensive and time-consuming inference methods such as Markov chain Monte Carlo.Methods.We present ExoMDN, a machine-learning model for the interior characterization of exoplanets based on mixture density networks (MDN). The model is trained on a large dataset of more than 5.6 million synthetic planets below 25 Earth masses consisting of an iron core, a silicate mantle, a water and high-pressure ice layer, and a H/He atmosphere. We employ log-ratio transformations to convert the interior structure data into a form that the MDN can easily handle.Results.Given mass, radius, and equilibrium temperature, we show that ExoMDN can deliver a full posterior distribution of mass fractions and thicknesses of each planetary layer in under a second on a standard Intel i5 CPU. Observational uncertainties can be easily accounted for through repeated predictions from within the uncertainties. We used ExoMDN to characterize the interiors of 22 confirmed exoplanets with mass and radius uncertainties below 10 and 5%, respectively, including the well studied GJ 1214 b, GJ 486 b, and the TRAPPIST-1 planets. We discuss the inclusion of the fluid Love numberk2as an additional (potential) observable, showing how it can significantly reduce the degeneracy of interior structures. Utilizing the fast predictions of ExoMDN, we show that measuringk2with an accuracy of 10% can constrain the thickness of core and mantle of an Earth analog to ≈13% of the true values.
Evidence for a gamma-ray molecular target in the enigmatic PeVatron candidate LHAASO J2108+5157
Authors: de la Fuente E. , Toledano-Juárez I. , Kawata K. , Trinidad M. A. , Yamagishi M. , Takekawa S. , Tafoya D. , Ohnishi M. , Nishimura A. , Kato S. , Sako T. , Takita M. , Sano H. , Yadav R. K. 
Published: June 2023

Context. Peta-eV (PeV) astronomy emerged in 2021 with the discovery of ultra-high-energy gamma-ray sources associated with powerful natural particle accelerators known as PeVatrons. In order to determine the nature of their emission, namely whether it has a hadronic or leptonic origin, it is essential to characterise the physical parameters of the environment where it originates.
Aims. We unambiguously confirm the association of molecular gas with the PeVatron candidate LHAASO J2108+5157 using unprecedented high angular-resolution (17″) 12, 13CO(J = 1 → 0) observations carried out with the Nobeyama 45m radio telescope.
Methods. We characterised a molecular cloud in the vicinity of the PeVatron candidate LHAASO J2108+5157 by determining its physical parameters from our 12, 13CO(J = 1 → 0) line observations. We used an updated estimation of the distance to the cloud, which provided a more reliable result. The molecular emission was compared with excess gamma-ray images obtained with Fermi-LAT at energies above 2 GeV to search for spatial correlations and test a possible hadronic (π0 decay) origin for the gamma-ray emission.
Results. We find that the morphology of the spatial distribution of the CO emission is strikingly similar to that of the Fermi-LAT excess gamma ray. By combining our observations with archival 21 cm HI line data, the nucleons (HI + H2) number density of the target molecular cloud is found to be 133.0 ± 45.0 cm−3, for the measured angular size of 0.55 ± 0.02° at a distance of 1.6 ± 0.1 kpc. The resulting total mass of the cloud is M(HI + H2) = 7.5±2.9×103 M⊙. Under a hadronic scenario, we obtain a total energy of protons of Wp = 4.3 ± 1.5 × 1046 erg with a cutoff of 700±300 TeV, which reproduces the sub-PeV gamma-ray emission.
Conclusions. We identified a molecular cloud in the vicinity of LHAASO J2107+5157 as the main target where cosmic rays from an unknown PeVatron produce the observed gamma-ray emission via π0 decay.
Further results on outer independent 2-rainbow dominating functions of graphs
Authors: Samadi Babak , Soltankhah Nasrin 
Published: June 2023

Let G = (V(G), E(G)) be a graph. A function f : V(G) → ℙ({1, 2}) is a 2-rainbow dominating function if for every vertex v with f(v) = ∅, f(N(v)) = {1, 2}. An outer-independent 2-rainbow dominating function (OI2RD function) of G is a 2-rainbow dominating function f for which the set of all v 2208 V(G) with f(v) = ∅ is independent. The outer independent 2-rainbow domination number (OI2RD number) γoir2(G) is the minimum weight of an OI2RD function of G. In this paper, we first prove that n/2 is a lower bound on the OI2RD number of a connected claw-free graph of order n and characterize all such graphs for which the equality holds, solving an open problem given in an earlier paper. In addition, a study of this parameter for some graph products is carried out. In particular, we give a closed (resp. an exact) formula for the OI2RD number of rooted (resp. corona) product graphs and prove upper bounds on this parameter for the Cartesian product and direct product of two graphs.
Verordnung von Antidiabetika und glykämische Kontrolle bei Erwachsenen mit Diabetes mellitus Typ 2 im zeitlichen Verlauf: Auswertung aus dem DPV-Register aus den Jahren 2005 bis 2021
Authors: Gölz Stefan , Eckert Alexander , Wosch Fran Jürgen , Hugenberg Inge , Karl Manuela , Seufert Jochen , Nun-Boetzel Heike , Wagner Siegfried , Weber-Lauffer Rosemarie , Milek Karsten , Naudorf Michael , Holl Reinhard Walter 
Published: June 2023

ZusammenfassungIn der vorliegenden Auswertung aus dem DPV-Register wird der Einsatz von unterschiedlichen
Antidiabetika zwischen den Jahren 2005 bis 2021 ausgewertet und analysiert. Es konnten Daten
von insgesamt 405790 Menschen mit Diabetes ausgewertet werden (2464078 Beobachtungsjahre). Die
Population (53,4 % männlich) war im Median 70,91 Jahre alt bei einer medianen Diabetesdauer
von ca. 9 Jahren. Im Laufe des Auswertungszeitraumes nahm der Anteil der über 80-jährigen
kontinuierlich zu.Seitens der Therapie nahm der Anteil der lediglich mit Insulin behandelten Patienten
ebenso ab wie der Anteil der lediglich mit Lebensstil behandelten Patienten. Metformin wurde
tendenziell zunehmend häufiger eingesetzt. Für Sulfonlyharnstoffe zeigte sich eine komplette
gegensätzliche Entwicklung gegenüber den DPP-IV-Inhibitoren mit einer Zunahme dieser seit 2007
etablierten Substanzgruppe. Seit ungefähr 2015 zeigen sich deutlich zunehmende
Verordnungshäufigkeiten für SGLT-2-Inhibitoren sowie GLP-1-Rezeptoragonisten bei gleichzeitig
zu erkennendem allmählichem Rückgang der DPP-IV-Inhibitorverordnungen.Während der Anteil der Metformin-Verordnungen im Beobachtungszeitraum in allen
Altersgruppen kontinuierlich und weitgehend parallel anstieg, sind für SGLT-2-Inhibitoren und
GLP-1-Rezeptoragonisten anfänglich bei der Gruppe der unter 60-jährigen und erst zeitversetzt
auch der älteren Patienten eingesetzt worden. Seitens der Geschlechterunterschiede in den
Verordnungen gibt es für GLP-1-Rezeptoragonisten quasi keine Unterschiede, bei Metformin gibt
es ein ganz leichtes Überwiegen der männlichen Patienten, welches bei SGLT-2-Inhibitoren
deutlicher wird.Die mittlere glykämische Kontrolle ausgedrückt durch den HbA1c-Wert liegt in der gesamten
Kohorte im Median bei 7,11 % (54,2 mmol/Mol) mit einem weitgehend unveränderten Verlauf über
den Beobachtungszeitraum und einer klaren Differenzierung dahingehend, dass jüngere Patienten
den höchsten medianen HbA1c aufweisen und die älteste Kohorte den niedrigsten.Die Daten werden im Kontext sich ändernder Leitlinien und Empfehlungen diskutiert und
analysiert.
Universal Urine Drug Screening with Rapid Confirmation upon Admission to Labor and Delivery
Authors: Haizler-Cohen Lylach , Collins Ana , Kaplan Dana M. , Giri Priyadarshani , Davidov Adi , Blau Jonathan , Fruhman Gary 
Published: June 2023

Objective This study aimed to describe our experience with universal urine drug screening (UDS) with rapid confirmation (RC) via liquid chromatography mass spectrometry (LC-MS) before infant's discharge, in efforts to increase detection of neonates at risk of neonatal opioid withdrawal syndrome (NOWS) while reducing patient burden related to false positive results.
Study Design Two-phase retrospective study of all pregnant women admitted to our labor and delivery (L&D) unit before (phase 1, April 2018–March 2019) and after (phase 2, October 2019–September 2020) RC of UDS was initiated. Urine samples were obtained on admission and screened for drugs using an enzyme immunoassay with positive results reflexed to confirmation via LC-MS. The turnaround time for LC-MS was 1 week in phase 1 and 24 hours in phase 2. For mothers with positive LC-MS confirmation, the infant's meconium was sent for drug screening. Positive results were determined to be true or false positive based on urinary LC-MS results. The primary outcome was the rate of opioid-positive mothers who were unanticipated. The secondary outcome was the difference in rate of neonates who were observed for NOWS, before and after implementation of RC with LC-MS.
Results In phase 2, a total of 2,395 deliveries occurred of which 2,122 (88.6%) had available UDS results. Fifty-two (2.5%) women had a positive UDS for at least one drug with LC-MS confirmation. Of those, 25 were true positive and 27 were false positive. Twenty-one (84%) true positive mothers were taking opioids and 8 (37%) of them were unanticipated positives. Among mothers with positive UDS for opioids, the neonatal observation rate for development of NOWS was 100% (22/22) and 48% (21/44) before and after implementation of LC-MS RC, respectively.
Conclusion Universal UDS and LC-MS RC in L&D may improve detection of unanticipated positive mothers whose infants are at risk of NOWS. RC of positive results allows intervention only for confirmed cases.
Key Points
Determination of the Sterilization Dose of Gamma-Ray Irradiation for Polyvinyl Alcohol-Collagen-Chitosan Composite Membrane as a Material for Periodontal Regenerative Surgery
Authors: Susanto Agus , Komara Ira , Beatrix Maria Theresia , Lukitowati Fajar , Amaliya Amaliya , Hendiani Ina , Miranda Aldilla 
Published: June 2023

Abstract
Objective Membrane sterility is very necessary considering its function as an implant material. Therefore, this research aims to determine the dose of gamma-ray irradiation for the sterilization of polyvinyl alcohol (PVA)–collagen–chitosan composite membranes used as regenerative surgery materials.
Materials and Methods A total of 100 pieces of the composite membranes were prepared in a size of 2.0 × 1.5 cm by mixing 7.5% PVA, 3% collagen, and 2% chitosan using the film casting method in three batches. Furthermore, the bioburden test was performed to determine the initial microbial count in the sample by following ISO 11737-1. The results were used to ascertain the dose of gamma-ray irradiation on the sample according to ISO 11137-2. The dose verification test was then performed at the sterility assurance level 10−6.
Results The average result of the bioburden test from three batches was 6.6 colony forming unit; hence, the verification dose was 4.8 kGy. In the verification dose test, since there was only one contaminated sample, the sterility dose test was continued.
Conclusion The sterile gamma-ray irradiation dose for PVA–collagen–chitosan composite membrane was 17.1 kGy.
Mindfulness trait mediates between schizotypy and hallucinatory experiences
Authors: Tagami Ubuka , Imaizumi Shu 
Published: June 2023

AbstractSchizotypy is a personality trait in healthy people that is related to schizophrenic symptoms. People with high schizotypy tend to have hallucinatory experiences. The relationship between high schizotypy and hallucinatory experiences could be explained by mindfulness traits and stress. To test our hypothesized model, we conducted a preregistered online survey in a Japanese non-clinical sample. In the preregistered analysis, structural equation modeling revealed that our model insufficiently fit our data and stress did not mediate between schizotypy and hallucinatory experiences. However, consistent with our hypothesis, mindfulness traits mediated between them. Exploratory analysis revealed that the model including three facets of mindfulness traits (i.e., observing, acting with awareness, and non-judging) as mediators fit our data best. These findings suggest that attention to current experiences could be a key factor in understanding the cognitive mechanisms underlying hallucinatory experiences in schizotypy and hallucinations in schizophrenia.
Has corporate involvement in government-initiated corporate social responsibility activities increased corporate value?—Evidence from China’s Targeted Poverty Alleviation
Authors: Jing Jielin , Wang Jianling , Hu Zhuochen 
Published: June 2023

AbstractPoverty remains the biggest challenge facing the world today. In 2016, the Chinese government launched a national campaign to eradicate poverty by 2020, among which Chinese listed companies have made significant contributions to. This paper focuses on the targeted poverty alleviation (TPA) and investigates the relationship between corporate participation in TPA and its corporate value. As compared to firm’s own corporate social responsibility (CSR) initiatives, participating in government-initiated CSR activities can better enhance corporate value. This is especially so when firms engage in penetrative “integrated poverty alleviation” rather than the direct approach of “donative poverty alleviation”. This paper adopts the Mediating Effect Model to explain the relationship between corporate participation in TPA and their corporate value, with the shareholding ratio of institutional investors, government subsidies and corporate reputation as mediating factors. Findings suggest that corporations’ active implementation of TPA actions can increase the shareholding ratio of institutional investors and government subsidies and improve corporate reputation, thereby significantly increasing their corporate value. However, the impact of participation in TPA on corporate value is limited by factors including the nature of property rights, the intensity of competition in the industry and the degree of marketization. The impact is generally more significant in state-owned enterprises, areas with lesser industry competition and higher marketization. This study provides a fresh perspective for theories related to CSR, poverty eradication and corporate value of listed companies.
Ladder symmetries of black holes and de Sitter space: love numbers and quasinormal modes
Authors: Berens Roman , Hui Lam , Sun Zimo 
Published: June 2023

Abstract
In this note, we present a synopsis of geometric symmetries for (spin 0) perturbations around (4D) black holes and de Sitter space. For black holes, we focus on static perturbations, for which the (exact) geometric symmetries have the group structure of
SO(1,3). The generators consist of three spatial rotations, and three conformal Killing vectors obeying a special melodic condition. The static perturbation solutions form a unitary (principal series) representation of the group. The recently uncovered ladder symmetries follow from this representation structure; they explain the well-known vanishing of the black hole Love numbers. For dynamical perturbations around de Sitter space, the geometric symmetries are less surprising, following from the SO(1,4) isometry. As is known, the quasinormal solutions form a non-unitary representation of the isometry group. We provide explicit expressions for the ladder operators associated with this representation. In both cases, the ladder structures help connect the boundary condition at the horizon with that at infinity (black hole) or origin (de Sitter space), and they manifest as contiguous relations of the hypergeometric solutions.
A diffeomorphism invariant family of metric-affine actions for loop cosmologies
Authors: Delhom Adrià , Olmo Gonzalo J. , Singh Parampreet 
Published: June 2023

AbstractIn loop quantum cosmology (LQC) the big bang singularity is generically resolved by a big bounce. This feature holds even when modified quantization prescriptions of the Hamiltonian constraint are used such as in mLQC-I and mLQC-II. While the later describes an effective description qualitatively similar to that of standard LQC, the former describes an asymmetric evolution with an emergent Planckian de-Sitter pre-bounce phase even in the absence of a potential. We consider the potential relation of these canonically quantized non-singular models with effective actions based on a geometric description. We find a 3-parameter family of metric-affinef(ℛ) theories which accurately approximate the effective dynamics of LQC and mLQC-II in all regimes and mLQC-I in the post-bounce phase. Two of the parameters are fixed by enforcing equivalence at the bounce, and the background evolution of the relevant observables can be fitted with only one free parameter. It is seen that the non-perturbative effects of these loop cosmologies are universally encoded by a logarithmic correction that only depends on the bounce curvature of the model. In addition, we find that the best fit value of the free parameter can be very approximately written in terms of fundamental parameters of the underlying quantum description for the three models. The values of the best fits can be written in terms of the bounce density in a simple manner, and the values for each model are related to one another by a proportionality relation involving only the Barbero-Immirzi parameter.
Covert-inspired flaps: an experimental study to understand the interactions between upperwing and underwing covert feathers
Authors: Zekry Diaa A , Nam Taewoo , Gupta Rikin , Zhu Yufei , Wissa Aimy A 
Published: June 2023

Abstract
Birds are agile flyers that can maintain flight at high angles of attack (AoA). Such maneuverability is partially enabled by the articulation of wing feathers. Coverts are one of the feather systems that has been observed to deploy simultaneously on both the upper and lower wing sides during flight. This study uses a feather-inspired flap system to investigate the effect of upper and lower side coverts on the aerodynamic forces and moments, as well as examine the interactions between both types of flaps. Results from wind tunnel experiments show that the covert-inspired flaps can modulate lift, drag, and pitching moment. Moreover, simultaneously deflecting covert-inspired flaps on the upper and lower sides of the airfoil exhibit larger force and moment modulation ranges compared to a single-sided flap alone. Data-driven models indicate significant interactions between the upper and lower side flaps, especially during the pre-stall regime for the lift and drag response. The findings from this study are also biologically relevant to the observations of covert feathers deployment during bird flight. Thus, the methods and results summarized here can be used to formulate new hypotheses about the coverts role in bird flight and develop a framework to design covert-inspired flow and flight control devices for engineered vehicles.
Recent massive expansion of wildfire and its impact on active layer over pan-Arctic permafrost
Authors: Zhu Xingru , Xu Xiyan , Jia Gensuo 
Published: June 2023

Abstract
Wildfire is recognized as an increasing threat to the southern boreal forests and the permafrost beneath them, with less occurring over the cold continuous permafrost than before. However, we show that continuous permafrost was a major contribution to wildfire expansion in the pan-Arctic over the last two decades. The expansion rate of burned area over continuous permafrost was 0.9 Mha decade−1, in contrast to a decreasing trend (−0.5 Mha decade−1) over the entire permafrost areas. Burned area has been rapidly growing in the north of the Arctic Circle in particular, where the total burned area in the major fire seasons during 2011–2020 nearly doubled that during 2001–2010. Wildfire expansion is closely linked to an increased soil moisture deficit, considering wildfires there combust more than 90% of belowground fuel. Continuous permafrost experiences more severe fire-induced degradation. Active layer thickening following wildfires over continuous permafrost lasts more than three decades to reach a maximum of more than triple the pre-fire thickness. These new findings highlight the massive expansion of wildfires over continuous permafrost, which can dramatically modify ecological processes, disturb organic carbon stock, and thus accelerate the positive feedback between permafrost degradation and climate warming.