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The velocity field of the Scorpius-Centaurus OB association
No full textWe present a nonparametric reconstruction of the three-dimensional velocity field of the Scorpius-Centaurus OB association (Sco-Cen). Using Gaia DR3 astrometry and radial velocities, we inferred the velocity field using information field theory on a 70 × 70 × 50 grid at a 3 pc resolution. Our model suggests the existence of a primary stellar velocity field with a secondary field that accounts for an additional young kinematic component in Upper Scorpius and Lupus. We find clear tracers of a feedback-driven expansion of the association, while Galactic rotation appears to play a subordinate role. The results confirm the existence of cluster chains and reveal coherent large-scale expansion with characteristic speeds of 1–2 km s−1 and local maxima of about 10 km s−1. Power spectra indicate an excess of small-scale structure and slopes shallower than Kolmogorov, consistent with energy injection from stellar feedback. Maps of the divergence reveal net positive values, implying an approximate dispersal timescale of 10–15 Myr. A comparison with molecular gas in Lupus and Ophiuchus shows broadly consistent patterns but systematic velocity offsets of several km s−1, suggesting partial decoupling for optically visible young stars and gas. The framework presented provides a physically motivated description of the Sco-Cen velocity field and a basis for quantifying the dynamical state and feedback history of OB associations in the local Galaxy
Radio-continuum spectra of pulsars with free-free thermal absorption
No full textThe radio continuum spectra of pulsars (PSRs) exhibit a wide variety of shapes, which are interpreted as pure and broken power laws, power laws with turnovers or cutoffs, and logarithmic-parabolic profiles. A notable fraction of these have well-defined power laws with ν−2.1 exponential turnovers, indicative of free-free thermal absorption along the line of sight. We analysed a sample of 63 PSRs with such spectral shapes, compiled from four previously published studies, to investigate their statistical properties. We normalised each spectrum to a characteristic frequency and flux density of its own, facilitating a consistent treatment across the four subsamples. We show that these two fitted parameters are correlated by a power law, with its slope reflecting the median spectral index (∼−2.0) of PSR emission. We find that the turnover frequencies in our sample are typically high, clustering around 558 MHz, which implies notably high emission measures (∼105 pc cm−6) for an inferred thermal absorbing medium with an electron temperature of 8000 K. Moreover, by combining these emission measures with dispersion measures derived from pulse time delays, we break the degeneracy between the electron density and the path length of the absorbers. This reveals a discrete near-in population of absorbers characterised by small sizes (∼0.1 pc) and high electron densities (∼103 cm−3), which exhibit a clear size-density anti-correlation reminiscent of that observed in Galactic and extragalactic H i
A joint 1% calibration of the RR Lyrae and type-II Cepheid Leavitt laws yields homogeneous distances to 93 Galactic globular clusters
No full textRecent work has established large samples of astrometrically confirmed RR Lyrae and type-II Cepheid members of Galactic globular clusters (GCs). Any given GC can contain multiple such stars at once, notably RR Lyrae stars pulsating in the fundamental mode (RRab) or the first overtone (RRc), and type-II Cepheids (T2Cep) of BL Her and W Vir types. Here, we present the first joint calibration of the Leavitt laws (LL) exhibited by 802 RRab, 345 RRc, and 21 T2Cep stars anchored to trigonometric parallaxes. Using the third data release of the ESA Gaia mission (GDR3), we have calibrated the intercepts of the RRab and RRc Leavitt laws in the reddening-free Gaia Wesenheit magnitude, MGW, to better than 1.0% in distance, and that of T2Cep to 1.3%, using a global fit to all data. The absolute scale is set by 37 nearby GCs with high-accuracy parallaxes while 56 additional GCs provide constraints on LL slopes as well as the LL intercept differences of RRc and T2Cep relative to RRab stars. Our global fit yields homogeneous high-accuracy distances of 93 GCs that show no evidence of bias for Gaia parallaxes of distant GCs. Control of systematics was demonstrated by 30 alternative fit variants, notably involving different treatments of metallicity effects, as well as by Markov Chain Monte Carlo analysis. Our results suggest that photometric metallicities of RR Lyrae stars require further improvements while also exhibiting possible signs of intra-cluster chemical inhomogeneity. This work lays the foundation for exploiting RRab, RRc, and T2Cep stars as high-accuracy standard candles for near-field cosmology and the extragalactic distance scale
Post early Cretaceous evolution of the Cévenol fault system according to U-Pb geochronology
No full textThe Le Teil (Rhône Valley) earthquake of magnitude 4.9 on November 11, 2019, located on the Cévennes fault system has raised many questions about how regional intraplate structures may be reactivated and how they could potentially trigger strong and shallow earthquakes. This study aims to better understand the geodynamic evolution of this major structure of France’s geology over geological time. A structural study was carried out between Alès and Cruas localities, and synkinematic calcite samples were collected on fault planes and dated using the U-Pb method at LA-HR-ICPMS. Four major geodynamic episodes between 110 and 25 Ma were identified. In addition to recording tectonic events related to plate boundary geodynamics, the Cévenol Fault System appears to be a key structure in accommodating vertical motion differentials between the Massif Central, the Pyrenean domain and the South-East basin
An asymptotic shape theorem for additive random linear growth models
No full textIn this paper, we define a class of additive random growth models whose growth is at least and at most linear and prove an asymptotic shape theorem for these models. This proof generalizes already known proofs for the classical contact process [T.E. Harris, Ann. Probab. 2 (1974) 969–988; R. Durrett and D. Griffeath, Z. Wahrsch. Verw. Gebiete 59 (1982) 535–552] or some of its variants (contact process on supercritical random environment [O. Garet and R. Marchand, Ann. Appl. Probab. 22 (2012) 1362–1410] or contact process with aging [A. Deshayes, ALEA Lat. Am. J. Probab. Math. Stat. 11 (2014) 845–883]) and allows us to obtain conjectured asymptotic shape theorems for Richardson’s model with stirring and the contact process with stirring [R. Marchand et al., arXiv 2504.0362
Research on the optimal allocation of shared energy storage in distribution networks considering the network reconfiguration and equivalence of distributed photovoltaic clusters
No full textShared Energy Storage System (ESS) plays a crucial role in addressing distributed Photovoltaic (PV) curtailment and mitigating distribution network investment costs. To this end, this paper proposes an optimal configuration strategy for shared ESS that considers both the equivalent modeling of distributed PV clusters and distribution network reconfiguration. Firstly, a distributed PV cluster equivalent model was developed, which simultaneously considers electrical distance and active power balance, to facilitate the clustering and equivalencing of distributed PV systems. Secondly, an optimization model for the allocation of shared ESS, considering network reconfiguration and PV clustering results, is proposed. This model minimizes investment costs and maximizes PV energy consumption, while comprehensively considering operational constraints related to PV, ESS, and distribution network reconfiguration. Thirdly, to address the challenge of model solving, a chaotic neural network algorithm is developed by integrating chaotic local search and quasi-oppositional-based learning methods to solve the proposed mixed-integer nonlinear optimization model. Finally, the effectiveness of the proposed method is demonstrated through several case studies based on the IEEE test systems, and the obtained Pareto optimal frontier can provide effective guidance for investors
Supply Chain Analysis of Cayenne Pepper (
No full textThis study emphasizes whether the chili supply chain process achieves operational efficiency improvements, cost reductions, product availability, in meeting customer demand in a timely manner. The objective is to analyze the cayenne pepper supply chain and analyze the performance of the cayenne pepper supply chain at the Manonda Inpres Market, Palu City. Using the Purposive Sampling and Snowball Sampling approaches, a sample of 50 farmers, 12 collectors, 35 retailers, and 85 consumers was obtained. Based on the Food Supply Chain Network analysis, the cayenne pepper supply chain consists of two channels with interconnected product, financial, and information flow structures, where relationships between actors are built on trust and direct communication. The product flow system is from upstream (farmers) to downstream (consumers), the financial flow is from downstream to upstream, and the information flow is two-way. The main difference between the two channels is the presence of collector traders, who add a distribution stage but expand the supply range. Overall, the performance of the chili pepper supply chain is relatively efficient, as the farmer share of both channels is greater than 50%, and the efficiency value is less than 33%. However, the first channel is superior and more efficient, as it provides greater benefits for farmers and retailers
Food Safety Risk Perception of Market Consumer in Surakarta City
No full textFood safety is a very important global issue, with various challenges that continue to emerge around the world. As the main provider of fresh and safe food to consumers, food safety, such as sanitation and hygiene, is considered important and value-added by consumers. Understanding how consumers perceive risks related to the safety and quality of the products they buy in both types of markets, this study is expected to provide a clearer picture of the effectiveness of the implementation of food safety standards from the consumers' perspective. The results showed that the level of consumer risk perception was categorized as high. In addition, there is no difference in risk perception between consumers of Nationally accredited local market that have implemented food safety standards and non accridited local market that have not implemented food safety standards
Particularités de l’infarctus du myocarde chez la femme
No full textL’infarctus du myocarde est un problème majeur de santé publique chez les femmes. Les taux d’hospitalisation sont en augmentation, en particulier chez les jeunes femmes. Cette tendance est probablement liée à une prévalence croissante des facteurs de risque cardiovasculaires et à des maladies spécifiques susceptibles d’augmenter le risque d’infarctus du myocarde : ménopause précoce, contraception œstroprogestative, endométriose et radiothérapie thoracique pour cancer du sein. D’un point de vue physiopathologique, les femmes présentent des caractéristiques distinctes de celles des hommes. Une proportion plus élevée d’infarctus du myocarde sans obstruction coronaire est observée chez la femme, notamment, la dissection spontanée des artères coronaires, qui peut parfois survenir pendant la grossesse. Les femmes ont des artères coronaires et radiales plus petites, avec des tortuosités plus fréquentes, ce qui peut compliquer les procédures interventionnelles. De plus, la prise en charge de l’infarctus du myocarde chez les femmes est inégale car : elles ont tendance à consulter plus tard et sont donc moins susceptibles de bénéficier de stratégies invasives (revascularisation ou pontage aorto-coronarien). En conclusion, l’infarctus du myocarde chez la femme présente de nombreuses spécificités cliniques et physiopathologiques. Des efforts supplémentaires sont nécessaires pour adapter les soins aux spécificités féminines et garantir une prise en charge équitable
Diversity and Distribution of Diurnal Predatory Insects of
No full textPredatory insects are among the natural enemies that can significantly reduce Spodoptera frugiperda populations. This species has been reported to spread into Magelang Regency, Central Java. Therefore, this study aimed to study the diversity and spatial distribution of diurnal predatory insects associated with S. frugiperda in the region. The research was conducted from December 2023 to May 2024. Sampling sites were selected using a stratified method, while maize fields within each site were chosen purposively. Insects were collected using hand-picking and sweeping net methods. Environmental data were also collected. The diversity of predatory insects found was analyzed descriptively. The relationship between predator abundance and abiotic factors was analyzed using simple correlation and regression. The results showed that 15 species of predatory insects of S. frugiperda were found in Magelang Regency. The predatory insects found came from three orders: Coleoptera, Hymenoptera, and Dermaptera. The most abundant species found was Coccinella transversalis (Coleoptera: Coccinellidae). These predatory insects were found in almost every region in Magelang Regency with varying abundances. However, most predators were found in the western and southern regions. These results provide information on the presence of local predators that can be utilized in future S. frugiperda management programs sustainably