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Rethinking Carbon Pricing: Balancing Market Incentives and Environmental Protection Through BUMICX
No full textThis article analyses the paradox of green development in Indonesia, which on the one hand promotes the energy transition agenda and global climate commitments, but on the other hand continues to strengthen its dependence on fossil fuels, particularly coal. Using a mixed approach that combines normative legal analysis and empirical studies of emissions data, fiscal regulations, and energy policies, this research shows that carbon tax instruments in Indonesia still function more as a means of political-economic legitimacy than as effective instruments for controlling emissions. The cap-and-tax model that has been adopted risks turning emissions into a financial commodity rather than an ecological limit that must be adhered to. To address these weaknesses, this article proposes the Balanced Upgraded Model for Integrated Carbon Taxation (BUMICX) as an innovative policy framework. This model positions carbon tax not only as a source of state revenue, but also as a structural mechanism to encourage green investment, strengthen institutions, and ensure ecological and social justice. The findings of this study confirm that without consistent and certain regulatory reform, market orientation tends to override environmental protection, putting decarbonization efforts at risk of being trapped in rhetoric without real transformation
CrackVision: A Bayesian CNN–Vision Transformer Bagging Ensemble for Enhancing Multiclass Concrete Crack Severity Classification
No full textThis paper presents CrackVision, a bagging ensemble integrating a Bayesian Convolutional Neural Network (BCNN) and Vision Transformer (ViT) for multiclass concrete crack severity classification. Unlike binary detection systems, CrackVision categorizes cracks into four levels None, Low, Medium, High with uncertainty awareness through Monte Carlo dropout. The system was trained on 60,000 augmented crack images and evaluated against standalone models. CrackVision achieved 99.31% accuracy and F1-scores up to 99.94%, improving performance by 2.17% over BCNN and 0.25% over ViT. Confusion matrix analysis confirmed fewer misclassifications than BCNN across all severity levels. Predictive uncertainty estimates enhance reliability for safetycritical deployment. These findings highlight CrackVision’s potential as a robust tool for automated infrastructure monitoring, particularly in disaster-prone regions requiring accurate crack assessment
TL1A, une alarmine qui coopère avec IL-33 dans l’initiation de l’inflammation allergique des voies respiratoires
No full textX-Ray Diffraction (XRD) Analysis of Local Rock Minerals from the Geological Zones of Dembek and Wariab Villages, West Papua
No full textThis study aims to characterize the minerals in rock samples from Dembek and Wariab Villages, South Manokwari Regency, West Papua, using the X-ray Diffraction (XRD) method. XRD was used to identify crystalline phases and mineral compositions in the rocks, as well as to understand the geological conditions and mineral resource potential in the area. Rock samples were systematically collected from both locations and analyzed using an X-ray diffractometer. The analysis results show that the rocks from Dembek Village are dominated by quartz (SiO2), Sodium Aluminum Silicate (Na1.45 Al1.45 Si0.55 O4), Potassium Aluminum Silicate (KAlSi2O6 and KAlSiO4), Potassium Silicon Fluoride (K2SiF6), Albite (Na (Si3Al)O8), Magnesium (Mg), Sodium Magnesium Aluminum Silicate (Na3MgAlSi2O8), and Potassium Magnesium Silicate (K2MgSi5O12). The rocks from Wariab Village contain a more varied range of minerals from two sampling points, namely, at the WRB-L1 location, consisting of halite (NaCl), quartz (SiO2), Potassium Magnesium Fluoride (KMgF3), Potassium Magnesium Silicate (K2MgSi5O12), anorthite (CaAl2Si2O8), and Potassium Aluminum Silicate (KAlSi2O6). The WRB-L2 location consisted of fluorite (CaF2), Potassium Silicon Fluoride (K2S1F6), sylvite (KCl), sodalite (Na4Al3Si3O12Cl), and Sodium Aluminum Silicate (Na1.65 Al1.65 Si0.35 O4). These differences in mineral composition reflect variations in the formation environment and geochemical processes that occur at each location
Altermagnétisme : la face cachée du monde magnétique
No full textQuand nous pensons à un matériau magnétique, nous imaginons instinctivement un aimant et le champ magnétique qu’il produit de lui-même. C’est en effet cette propriété qui est exploitée dans de nombreuses applications de la vie courante : transformateurs électriques, moteurs, générateurs, capteurs, appareils médicaux, appareils électroménagers, stockage de données… Cependant, il existe de nombreux matériaux qui ne sont pas spontanément aimantés et qui, pourtant, possèdent microscopiquement un ordre magnétique bien déterminé. Cet article met en lumière une famille de matériaux de ce genre, découverte récemment : les altermagnétiques. Leurs propriétés, supérieures par bien des aspects à celles des aimants usuels, élargissent le spectre des applications des matériaux magnétiques, notamment dans le domaine de l’électronique de spin
Dossier « Les professionnels de la montagne face aux transitions socio-environnementales » – Reconfiguration de la gouvernance territoriale à l’aune de la transition touristique. Le cas des refuges de montagne dans les Alpes franco-suisses
No full textLa transition touristique constitue actuellement un défi majeur pour les refuges de montagne, et de manière plus générale, pour la montagne peu aménagée. Alors que les refuges connaissent une diversification marquée de leurs pratiques et de leur public, les propriétaires de ces établissements doivent faire face aux effets du changement climatique et à une augmentation significative des coûts de rénovation. La multifonctionnalité du refuge permet à un nombre croissant de parties prenantes de s’investir et de coopérer autour de cette structure. Nous observons ainsi un accroissement du cofinancement, une insertion plus fréquente du refuge dans un projet territorial ou encore des concertations pour diversifier les activités sur le territoire et réfléchir aux futurs des refuges. À travers l’étude de 6 vallées et de 22 refuges en France et en Suisse, cet article met en lumière la redéfinition de la gouvernance territoriale à l’aune de la transition touristique. Cette évolution se manifeste par des reconfigurations organisationnelles caractérisées par une concertation accrue entre les différents acteurs de la montagne peu aménagée
Energetics of star–planet magnetic interactions
No full textContext. Star–planet magnetic interactions (SPMIs) occurring in the sub-Alfvénic regime can, in principle, induce stellar chromospheric hotspots. These hotspots could serve as observational markers for inferring key planetary properties, especially the exoplanetary magnetic field, which is otherwise notoriously difficult to constrain. Currently, estimates of the power generated by SPMIs primarily rely on analytical scaling laws that relate stellar and planetary parameters to the interaction energetics. The existing scaling laws published in the literature so far do not agree with each other by at least an order of magnitude.
Aims. Our aim was to quantify an absolute upper limit on the power that a planet can channel back to its host star during such interactions, which in turn can lead to the formation of stellar hotspots. Furthermore, we explored how this energy varies with different planetary characteristics and the stellar wind conditions in the vicinity of the planet.
Methods. We employed three-dimensional numerical simulations of SPMIs in which the planet orbits within the sub-Alfvénic regime of the stellar wind. By performing a series of simulations with varied parameters known to influence the energetics of SPMIs, we derive a numerically supported scaling law that can be used to reliably estimate the energy channeled from the planet back to the star.
Results. Our results suggest that existing analytical scaling laws may not fully capture the power transferred from the planet to the star through SPMI. The scaling law derived from our numerical simulations appears to provide a more comprehensive estimate, reflecting dependences on common stellar and planetary parameters also considered in earlier models. Moreover, our findings indicate that power generation involves not only the planetary obstacle itself but also the extended magnetic structure of the Alfvén wings interacting with the streaming stellar wind.
Conclusions. This study suggests that care should be taken when applying analogies directly from Jovian sub-Alfvénic interactions to SPMIs, as the underlying physical conditions (specifically the value of the Alfvénic Mach number) may not be directly comparable. Our numerically derived scaling law offers a potentially improved approach for estimating SPMI power, capturing some of the interaction’s complexities exclusive to SPMIs
Validating a non-local stellar convection model with 3D hydrodynamics simulations
No full textContext. The efficient transport of energy and chemical elements by convective motions has a profound effect on the structure and evolution of stars. These motions occur on the relatively short dynamical timescale of convection and are intrinsically multi-dimensional. Stellar models usually rely on the one-dimensional mixing-length approximation of these processes, which is known to break down at convective boundaries. The Kuhfuß, R. (1987, Dissertation, Technische Universität München, München) convection model has been shown to handle convective boundaries in a more consistent way.
Aims. We test the assumptions that enter the Kuhfuß model using multi-dimensional hydrodynamics simulations, and we compare the results with existing one-dimensional models. Where possible, we also aim to calibrate the parameters of the Kuhfuß model using the simulations.
Methods. We computed one-dimensional stellar models employing the Kuhfuß model of a 3 M⊙ main-sequence star. These models were compared to three-dimensional hydrodynamic simulations obtained with the code called SEVE
The ALMA survey to Resolve exoKuiper belt Substructures (ARKS)
No full textContext. Debris discs were long considered to be largely gas-free environments, where dynamical evolution is governed primarily by collisional fragmentation, gravitational stirring, and radiative forces. Recent detections of CO molecular line emission in debris discs demonstrate that gas is present, but its abundance and origin are still uncertain. The ALMA survey to Resolve exoKuiper belt Substructures (ARKS) observed both the gas and dust of several debris discs at high resolution and revealed a narrow ring of gas and dust in the disc HD 121617, with an asymmetric arc-like feature that is 40% brighter than the rest of the ring.
Aims. An important open question is how representative the estimated CO masses are for the total gas mass in debris discs. We aim to constrain the total gas mass in HD 121617 using numerical models under the assumption that the dust arc is produced by hydrodynamical processes involving the gas.
Methods. We used the hydrodynamical code Dusty FARGO-ADSG, in which dust is modelled as Lagrangian particles. We explored the effects of radiation pressure and dust feedback, as well as of varying the total gas mass on the dynamical evolution of the system. We compared these simulations with observations via radiative transfer calculations.
Results. We find that an unstable gas ring can create a size-dependent radial and azimuthal dust trap. The total gas mass dictates the efficiency of particle trapping as a function of grain size. We find that two of our models, Mgas=50 M⊕ and Mgas=5 M⊕, can simultaneously reproduce the observed arc in the ALMA band 7 continuum image and the radial outward offset of the VLT/SPHERE scattered light ring, driven by the combined effects of gas drag and radiation pressure. We further find a conservative lower limit of Mgas>2.5 M⊕ and a conservative upper limit of Mgas<250 M⊕.
Conclusions. If the ALMA band 7 asymmetry is caused by gas drag, reconciling the required gas mass with the observed 12CO emission suggests the presence of significant amounts of H2, consistent with the gas being primordial, that is, long-lived remnant material from the protoplanetary disc phase. In this scenario, HD 121617 would represent a hybrid disc, bridging the protoplanetary and debris disc stages. As an arc-shaped emission can alternatively be reproduced by a planet’s gravitational forcing, future observations are crucial to distinguish between these two scenarios
A new broad K/Ka-band receiver (18.0–32.3 GHz) for the Yebes Observatory’s 40 meter radio telescope
No full textSince 2010, the 40 m radio telescope of the Yebes Observatory has been devoted to very long baseline interferometry (VLBI) and single-dish observations. Up until 2019, it covered frequency bands between 2 GHz and 90 GHz in discontinuous and narrow radio windows that met the needs of the European VLBI Network (EVN) and the Global Millimeter VLBI Array (GMVA). The situation changed in 2019 when new receivers were built and installed at the telescope for the Q- (31.5–50 GHz) and W- (72–90.5 GHz) bands in the frame of the Nanocosmos1 project, a synergy project funded by the European Research Council. The 18.5 GHz instantaneous bandwidth is now fully covered in the two polarisations with 16 fast Fourier transform (FFT) spectrometers of 38 kHz resolution. This has allowed us to achieve an unprecedented level of ultra-sensitivity for line surveys, leading to the discovery of around 95 molecules in space over the last six years. These results have encouraged the construction of a new low-noise cryogenic receiver between 18 GHz and 32.3 GHz for the 40 m radio telescope with orthogonal polarisations (H & V) and 19 kHz of spectral resolution. Due to the frequency resolution requirement and the limited number of FFT boards, the band has been split into two sub-bands for each polarisation: low-band (18–26 GHz) and high-band (26–32.3 GHz), with eight FFT spectrometers of 1 GHz instantaneous bandwidths per sub-band and per polarisation. Alternatively, the receiver can be configured to analyze the full receiver band (18–32.3 GHz) in a single polarisation (either H-pol or V-pol). Here, we present the characteristics of the receiver and the first astrophysical results demonstrating its performance. A detailed analysis of the radio frequency interferences (RFIs) generated by satellite down-link communications and its impact on spectroscopic studies of the interstellar and circumstellar media is also provided. In this context, we conclude that the radio astronomy community must continue to strive to protect the still RFI-free K/Ka radio windows from harmful radiocommunication signals