bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fractional calculus for distributions
Authors: Hilfer R. , Kleiner T. 
Published: August 2024

AbstractFractional derivatives and integrals for measures and distributions are reviewed. The focus is on domains and co-domains for translation invariant fractional operators. Fractional derivatives and integrals interpreted as "Equation missing"-convolution operators with power law kernels are found to have the largest domains of definition. As a result, extending domains from functions to distributions via convolution operators contributes to far reaching unifications of many previously existing definitions of fractional integrals and derivatives. Weyl fractional operators are thereby extended to distributions using the method of adjoints. In addition, discretized fractional calculus and fractional calculus of periodic distributions can both be formulated and understood in terms of "Equation missing"-convolution.
Mining Interpretable Regional Co-location Patterns Based on Urban Functional Region Division
Authors: Liu Yuqing , Wang Lizhen , Yang Peizhong , Zhou Lihua 
Published: August 2024

AbstractDiscovering the correlation relationships of spatial facilities in urban functional regions is of great significance in analyzing urban planning and promoting urban development. However, existing regional co-location pattern mining methods do not fully consider the attributes of urban functional regions. Consequently, they fail to effectively capture the relationships between spatial facilities and regions, resulting in patterns lacking practical application value and interpretability. To address this issue, this paper proposes a novel regional co-location pattern (RCP) mining method based on urban functional region division. First, an ontology-based method for urban functional region division is proposed. On the basis of dividing urban functional regions, the expected mean distance is generated to adaptively calculate the neighbor relationships between instances in each region, and a parallel algorithm is designed to quickly mine RCPs in urban functional regions. Then, the correlation coefficient ($$CC_{RP}$$

C

C

RP

) measures the association strength between RCP and function type to provide interpretability for RCPs. Finally, extensive experiments on real-world datasets are conducted to verify the effectiveness of urban functional region partition and to demonstrate the superiority of the proposed RCP mining method.
Leveraging local data sampling strategies to improve federated learning
Authors: Düsing Christoph , Cimiano Philipp , Paaßen Benjamin 
Published: August 2024

AbstractFederated learning (FL) facilitates shared training of machine learning models while maintaining data privacy. Unfortunately, it suffers from data imbalance among participating clients, causing the performance of the shared model to drop. To diminish the negative effects of unfavourable data-specific properties, both algorithm- and data-based approaches seek to make FL more resilient against them. In this regard, data-based approaches prove to be more versatile and require less domain knowledge to be applied efficiently. Hence, they seem particularly suitable for widespread application in various FL environments. Although data-based approaches such as local data sampling have been applied to FL in the past, previous research did not provide a systematic analysis of the potential and limitations of individual data sampling strategies to improve FL. To this end, we (1) identify relevant local data sampling strategies applicable to FL systems, (2) identify data-specific properties that negatively affect FL system performance, and (3) provide a benchmark of local data sampling strategies regarding their effect on model performance, convergence, and training time in synthetic, real-world, and large-scale FL environments. Moreover, we propose and rigorously test a novel method for data sampling in FL that locally optimizes the choice of sampling strategy prior to FL participation. Our results show that FL can greatly benefit from applying local data sampling in terms of performance and convergence rate, especially when data imbalance is high or the number of clients and samples is low. Furthermore, our proposed sampling strategy offers the best trade-off between model performance and training time.
On Loss Functionals for Physics-Informed Neural Networks for Steady-State Convection-Dominated Convection-Diffusion Problems
Authors: Frerichs-Mihov Derk , Henning Linus , John Volker 
Published: August 2024

AbstractSolutions of convection-dominated convection-diffusion problems usually possess layers, which are regions where the solution has a steep gradient. It is well known that many classical numerical discretization techniques face difficulties when approximating the solution to these problems. In recent years, physics-informed neural networks (PINNs) for approximating the solution to (initial-)boundary value problems ((I)BVPs) received a lot of interest. This paper studies various loss functionals for PINNs that are especially designed for convection-dominated convection-diffusion problems and that are novel in the context of PINNs. They are numerically compared to the vanilla and an hp-variational loss functional from the literature based on two steady-state benchmark problems whose solutions possess different types of layers. We observe that the best novel loss functionals reduce the $$L^2(\varOmega )$$

L
2

(
Ω
)

error by 17.3% for the first and 5.5% for the second problem compared to the methods from the literature.
Research progress of antibody–drug conjugates in gynecologic cancer
Authors: Xu Dongdong , Chen Zhe-Sheng , Peng Xuanwei , Lin Zhongqiu , Lu Huaiwu 
Published: August 2024

AbstractGynecologic cancer is a critical concern in the field of women’s health, and traditional treatment methods have demonstrated limited efficacy for certain advanced and recurrent gynecologic cancers. In recent years, antibody–drug conjugate (ADC) therapy, as an emerging targeted approach, has gained increasing attention as a research hotspot. This review aims to elucidate the structure and mechanism of ADC drugs and explore their application and clinical research progress in gynecologic cancers such as ovarian cancer, cervical cancer, and endometrial cancer.
The classified peri-urban forest of Kua from Burkina Faso must not be declassified for ecological reasons
Authors: Balima Larba Hubert , Kiemtoré Henry , Bayen Philippe , Zerbo Issouf , Ganamé Moussa , Cissé Mohamed , Thiombiano Adjima 
Published: August 2024

AbstractDensification of urban areas and rapid urbanization result in land scarcity in the Sahelian cities of West Africa. Therefore, urban greenspaces are increasingly coveted for socio-economic development. This is the case of the peri-urban forest of Kua in Burkina Faso which has been subject of controversies between ecologists and decision makers who intended to declassify this forest for hospital project. The lack of ecological evidence on this forest fueled the dichotomous conflicts between environment protection and urban planning. Hence, this study aimed to assess the ecological characteristics of the peri-urban forest of Kua. Dendrometric measurements of 2993 individuals were performed in 106 plots across the peri-urban forests of Kua and Dindéresso. We computed and compared tree diversity metrics, structural parameters and carbon stocks between the two forests. The findings revealed a γ–diversity of 40 woody species from 38 genera and 16 families in Kua forest. Through the diversity metrics, we found that the peri-urban forest of Kua exhibited lower tree diversity than the peri-urban forest of Dindéresso (p-value < 0.05). Similarly, tree density was significantly lower (p-value < 0.05) in Kua (212.446 ± 291.65 ind. ha−1) than in Dindéresso (378.461 ± 298.89 ind. ha−1). However, carbon stock was two times significantly higher (p-value < 0.05) in Kua (26.21 ± 31.27 Mg.ha−1) than in Dindéresso (13.389 ± 15.95 Mg.ha−1), highlighting the high potential of this forest in carbon sequestration. This study demonstrated that the peri-urban forest of Kua – despite its lower tree diversity and density – constitutes important carbon pools and sinks. Therefore, this forest must not be declassified, but should rather be reinforced through management plans and conservation actions. To sustain urban development, land management policies promoting the conservation of greenspaces are required to reduce biodiversity loss and carbon emissions in urban centers.
Under attack: Why and how I-O psychologists should counteract threats to DEI in education and organizations
Authors: Follmer Kayla Brooke , Sabat Isaac E. , Jones Kristen P. , King Eden 
Published: August 2024

AbstractIn recent years, there has been an alarming increase in both proposed and enacted legislation that targets diversity, equity, and inclusion (DEI) initiatives within higher education and organizations. These laws aim to dismantle protections and support for vulnerable individuals and groups. In this focal article, we provide an overview of the motives driving these anti-DEI legislative initiatives and categorize the laws based on the type of restrictions they impose: (a) reduction in knowledge, (b) reduction in access, and (c) reduction in support. Next, we discuss the consequences these anti-DEI laws yield for individuals, organizations, and society at large and provide an overview of how individuals and organizations may counteract these regressive policies. Last, we conclude with a call to action for I-O psychologists to investigate and call attention to the consequences of anti-DEI laws for recruitment and selection, well-being and safety of minoritized individuals, organizational reputation, and organizational performance and profits.
Paisajes agrícolas miniaturas de tiempos prehispánicos tardíos en las tierras altas de Arica (Andes centro sur)
Authors: Sepúlveda Marcela , Saintenoy Thibault , Santos Rubén 
Published: August 2024

ResumenLa agricultura fue una actividad fundamental de las comunidades aldeanas de las tierras altas de Arica en los Andes centro sur, durante el período Intermedio tardío (1100-1450 dC), hasta convertirse en uno de los principales propósitos de la expansión inca en la región en los siglos quince y dieciséis. Este trabajo presenta el hallazgo, en la cuenca alta del Valle de Azapa, de maquetas o infraestructuras agrícolas grabadas en miniatura. Caracterizamos sus formas y soportes, examinamos su distribución en los territorios tardíos de la región y las contrastamos a macroescala regional con evidencias similares. Finalmente, discutimos su vínculo con el flujo de conocimientos y experiencias relativos al manejo del agua y la topografía, junto con la ritualización del paisaje agrícola en tiempos incas.
Weak Mass Loss from the Red Supergiant Progenitor of SN 2021yja
Authors: Hosseinzadeh Griffin 
Published: August 2024

AbstractRecent observations of Type II supernovae have revealed that their red-supergiant progenitors lose a significant amount of mass during the last years of their evolution. However, because it is difficult to discover supernovae within days of explosion, the diversity of mass loss in red supergiants has not yet been fully mapped. This talk presented the case of SN 2021yja, which was serendipitously imaged within hours of explosion and observed with a sub-day cadence during its rise to peak. From the exceptionally long plateau period and the high nickel mass, we infer a relatively massive red-supergiant progenitor star. However, archival imaging from the Hubble Space Telescope places a stringent upper limit of on its progenitor mass. We discuss these conflicting constraints in the context of the larger sample of exploding red supergiants. Our analysis helps illuminate the poorly understood mechanism(s) behind red-supergiant mass loss.
ISOSCELES: Grid of stellar atmosphere and hydrodynamic models of massive stars
Authors: Araya Ignacio , Machuca Natalia , Curé Michel , Arcos Catalina 
Published: August 2024

AbstractSpectroscopy can decode the radiation from stars in an appropriate way and derive many properties of different stellar objects. In this work we seek to derive simultaneously stellar and wind parameters of massive stars. To model the data we use the radiative transport code Fastwind with the hydrodynamic solutions derived using our stationary code Hydwind as input, instead of the β-law. Then, ISOSCELES, our grid of stellar atmosphere and hydrodynamic models of massive stars, is used to derive the physical properties of the observed spectra through spectral line fittings. This quantitative spectroscopic analysis provide an estimation about the line–force parameters, whose theoretical calculations are complex. In addition, we expect to confirm that the hydrodynamic δ-slow solutions, describe quite reliable the radiation line-driven winds of A and late B supergiant stars and, at the same time, explain disagreements between observational data and theoretical models for the Wind–Momentum Luminosity Relationship (WLR).
Near and far: a hunt for binary-interaction products
Authors: Bodensteiner J. , Sana H. , Mahy L. , Shenar T. , Banyard G. , Wang C. 
Published: August 2024

AbstractDirect observations of the products of binary interactions are sparse, yet they provide important insights on the outcome of the interaction and the physics at play. Young and intermediate-age star clusters are the ideal tool to search for, and characterize such interaction products and allow for a detailed comparison to theoretical predictions. We here report on integral field spectroscopy obtained with MUSE for several such clusters in the Magellanic Clouds.
Structure in stellar winds of early B type supergiants
Authors: Parsons Timothy N. , Prinja Raman K. , Oskinova Lidia M. , Massa Derck L. 
Published: August 2024

AbstractOne significant difficulty in reliable quantification of the rates of mass-loss from hot, massive stars lies in uncertainties associated with quantifying temporal and spatial variability within stellar winds. The consequences of low-metallicity conditions for wind structure also merit continued investigation. We present initial results from ULLYSES data with the aim of identifying structure within the stellar winds of early B type supergiants with sub-solar metallicities in the Large and Small Magellanic Clouds. We demonstrate how single-epoch ULLYSES data can be used to investigate significant wind structure for these stars.
3D effects of rotation on spectroscopic observables
Authors: Abdul-Masih Michael 
Published: August 2024

AbstractWhen a star is rapidly rotating, it deviates from spherical symmetry causing non-uniform distributions of the surface gravity and temperature across the surface. These three-dimensional effects lead to an inclination dependence of many observable spectroscopic parameters, however this is often neglected when analyzing rapidly rotating systems. Using spamms, we generate synthetic spectra that account for the 3D geometry of the system and fit them with 1D models to investigate how much the 3D effects can change the derived stellar parameters. We show that these 3D effects can lead to observed temperature differences of thousands of kelvin for the same star viewed at different inclinations, and a systematic underestimation of the helium abundance.
How Much Hydrogen is in Type Ib and IIb SN Progenitors?
Authors: Gilkis Avishai , Arcavi Iair 
Published: August 2024

AbstractWe compare pre-supernova observations with synthetic photometry from stellar evolution models to infer the progenitor properties of the seven known progenitors of Type Ib and IIb supernovae. Our results are roughly consistent with a hydrogen mass threshold of for a Type II appearance.
Wray 15-906 low mass Luminous Blue Variable in a pre-supernova stage
Authors: Maryeva O. , Gvaramadze V. , Kniazev A. , Berdnikov L. 
Published: August 2024

AbstractThe evolutionary link between Red Supergiants and Luminous Blue variables is interesting, but still poorly understood. We present the results of a study of the Galactic candidate luminous blue variable Wray 15-906, revealed via the detection of its infrared circumstellar shell (of ≍2 pc in diameter) with the Wide-field Infrared Survey Explorer (WISE) and the Herschel Space Observatory. Using the stellar atmosphere code CMFGEN and the Gaia parallax, we found that Wray 15-906 is a relatively low-luminosity, log(L/Lȯ) ≍ 5.4, star with a temperature of 25±2 kK. In the framework of single star evolution, the obtained results suggest that Wray 15-906 is a post-red supergiant star with an initial mass of ≍ 25Mȯ and that before exploding as a supernova it could transform for a short time into a WN11h star. The presence of a shell with a mass 2.9±0.5Me indicates that Wray 15-906 has suffered substantial mass loss in the recent past.
Dynamical vs Supernova Acceleration of OB Stars in the Small Magellanic Cloud
Authors: Oey M. S. , Dorigo Jones J. , Phillips G. D. , Castro N. , Dallas M. M. , Moe M. 
Published: August 2024

AbstractWe use the RIOTS4 sample of SMC field OB stars to determine the origin of massive runaways in this low-metallicity galaxy using Gaia proper motions, together with stellar masses obtained from RIOTS4 data. These data allow us to estimate the relative contributions of stars accelerated by the dynamical ejection vs binary supernova mechanisms, since dynamical ejection favors faster, more massive runaways, while SN ejection favors the opposite trend. In addition, we use the frequencies of classical OBe stars, high-mass X-ray binaries, and non-compact binaries to discriminate between the mechanisms. Our results show that the dynamical mechanism dominates by a factor of 2 – 3. This also implies a significant contribution from two-step acceleration that occurs when dynamically ejected binaries are followed by SN kicks. We update our published quantitative results from Gaia DR2 proper motions with new data from DR3.
M 1-67 and RCW 58: nebulae around WN8h stars formed through CE evolution
Authors: Jiménez-Hernández P. , Arthur S. J. , Toalá J. A. , Marston A. P. 
Published: August 2024

AbstractWe present the analysis of the dust properties of the Wolf-Rayet nebulae M 1-67 and RCW 58 around the WN8h stars WR 124 and WR 40, respectively. Modeling with the photoionization code Cloudy shows that in both nebulae the IR spectral energy distributions and ionized gas properties can be reproduced by a dust shell consisting of two populations of dust grains. Furthermore, taking into account the initial mass, the morphology and the kinematics of the nebulae we propose M 1-67 and RCW 58, together with their progenitor stars, as the first observational evidences of post-common envelope evolution in nebulae around massive stars.
MWC 656: A Be+BH or a Be+sdO?
Authors: Rivinius Th. , Klement R. , Chojnowski S. D. , Baade D. , Shepard K. , Hadrava P. 
Published: August 2024

AbstractMWC 656 has been reported as classical Be star with a black hole companion. Revisited spectral variability properties render this unlikely, with a hot subdwarf more probable.
Wolf-Rayet stars: recent advances and persisting problems
Authors: Shenar Tomer 
Published: August 2024

AbstractWolf-Rayet (WR) stars comprise a class of stars whose spectra are dominated by strong, broad emission lines that are associated with copious mass loss. In the massive-star regime, roughly 90% of the known WR stars are thought to have evolved off the main sequence. Dubbed classical WR (cWR) stars, these hydrogen-depleted objects represent a crucial evolutionary phase preceding core collapse into black holes, and offer a unique window into hot-star wind physics. Their formation is thought to be rooted in either intrinsic mass-loss or binary interactions. Results obtained from analyses using contemporary model atmospheres still fail to reconcile the derived properties of WR stars with predictions from stellar evolution. Importantly, stellar evolution models cannot reproduce the the bulk of cWR stars, a problem that becomes especially severe at subsolar metallicity. Next-generation model atmospheres and upcoming observational campaigns to hunt for undetected companions promise a venue for progress.
Strong lithium lines in red supergiants at different metallicities
Authors: Negueruela Ignacio , Alonso-Santiago Javier , Dorda Ricardo , Patrick Lee R. 
Published: August 2024

AbstractCurrent models of stellar evolution predict that stars more massive than ∼6 M⊙ should have completely depleted all lithium (Li) in their atmospheres by the time when they reach the He core burning phase. Against this, a non-negligible number of red giants with masses ≳6 M⊙ presenting strong Li lines have recently been reported. Motivated by this finding, we have carried out a spectroscopic survey of red supergiants (RSGs) in the Perseus Arm and a selection of young open clusters in the Magellanic Clouds to assess the presence of the Li <sc>i</sc> 6708Å doublet line. Based on a sample of > 70 objects, close to one third of RSGs in the Perseus Arm display noticeable Li lines, with perhaps a trend towards a lower fraction among more luminous stars. The samples in the Magellanic Clouds are not as large, but hint at a metallicity dependence. Twenty one RSGs in 5 LMC clusters show a very high fraction of Li detection, around 40%. Conversely, 17 RSGs in 5 SMC clusters give only one secure detection. The interpretation of these observational results is not straightforward, but a mechanism for Li production seems most likely. Further characterisation work is ongoing, while theoretical studies into this matter are urgently needed.
Using machine learning to investigate the populations of dusty evolved stars in various metallicities
Authors: Maravelias Grigoris , Bonanos Alceste Z. , Tramper Frank , de Wit Stephan , Yang Ming , Bonfini Paolo , Zapartas Emmanuel , Antoniadis Konstantinos , Christodoulou Evangelia , Muñoz-Sanchez Gonzalo 
Published: August 2024

AbstractMass loss is a key property to understand stellar evolution and in particular for low-metallicity environments. Our knowledge has improved dramatically over the last decades both for single and binary evolutionary models. However, episodic mass loss although definitely present observationally, is not included in the models, while its role is currently undetermined. A major hindrance is the lack of large enough samples of classified stars. We attempted to address this by applying an ensemble machine-learning approach using color indices (from IR/Spitzer and optical/Pan-STARRS photometry) as features and combining the probabilities from three different algorithms. We trained on M31 and M33 sources with known spectral classification, which we grouped into Blue/Yellow/Red/B[e] Supergiants, Luminous Blue Variables, classical Wolf-Rayet and background galaxies/AGNs. We then applied the classifier to about one million Spitzer point sources from 25 nearby galaxies, spanning a range of metallicites (). Equipped with spectral classifications we investigated the occurrence of these populations with metallicity.
Progenitors and companions of stripped-envelope supernovae
Authors: Zapartas E. , Fox O. , Fragos T. , Renzo M. , Andrews J. , Bavera S. S. , Dotter A. , Drout M. , van Dyk S. , Milisavljevic D. , Kovlakas K. , Misra D. , Rocha K. , Smith N. , Williams B. , Xing Z. 
Published: August 2024

AbstractIn this poster, using the POSYDON code, we present results on binary progenitors of stripped-envelope SNe and their companions. We find that most progenitors are expected to explode, according to typical SN prescriptions (in contrast to single star progenitors). We also show the expected masses and position in the HR diagram of the companions of these SNe at the moment of explosion, allowing us to do a first statistical comparison with the compiled sample of observational detections (or upper limits) on these companions.