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The Atacama Cosmology Telescope: Observations of supermassive black hole binary candidates
No full textLarge sinusoidal variations in the radio light curves of the blazars PKS J0805–0111 and PKS 2131–021 have recently been discovered with an 18-year monitoring programme at the Owens Valley Radio Observatory, making these systems strong supermassive black hole binary (SMBHB) candidates. The sinusoidal variations in PKS 2131–021 dominate its light curves from 2.7 GHz to optical frequencies. We report sinusoidal variations observed in both objects with the Atacama Cosmology Telescope (ACT) at 95, 147, and 225 GHz consistent with the radio light curves. The ACT 95 GHz light curve of PKS 2131–021 agrees well with the contemporaneous 91.5 GHz ALMA light curve and is comparable in quality, while the ACT light curves of PKS J0805–0111, for which there are no ALMA or other millimetre light curves, show that PKS 2131–021 is not an isolated case, and that this class of AGN exhibits the following properties: (a) the sinusoidal pattern dominates over a broad range of frequencies; (b) the amplitude of the sine wave compared to its mean value is monochromatic (i.e. nearly constant across frequencies); (c) the phase of the sinusoid phase changes monotonically as a function of frequency; (d) the sinusoidal variations are intermittent. We describe a physical model for SMBHB systems, the modified Kinetic Orbital model, that explains all four of these phenomena. The monitoring of ∼8000 blazars by the Simons Observatory over the next decade should provide a large number of SMBHB candidates that will shed light on the nature of the nanohertz gravitational-wave background
Retraction Notice: A review of weather conditions monitoring system based on iot
No full textWe take a zero tolerance to any situation where fraudulent research is published in our journals. As a result, this article has been retracted by the Publisher because it is suspected to be a nonsensical computer-generated publication with a number of tortured phrases and irrelevant references.
Additional measures have been implemented to prevent these issues from reoccurring.
EDP Sciences is extremely grateful to anonymous whistleblowers and the Problematic Paper Screene
Retraction Notice: Taxonomic analysis of the fauna of coleoptera (beetles) in Bukhara region
No full textWe take a zero tolerance to any situation where fraudulent research is published in our journals. As a result, this article has been retracted by the Publisher because it is suspected to be a nonsensical computer-generated publication with a number of tortured phrases and irrelevant references.
Additional measures have been implemented to prevent these issues from reoccurring.
EDP Sciences is extremely grateful to anonymous whistleblowers and the Problematic Paper Screene
Retraction Notice: Detecting anomalous road traffic conditions using VGG19 CNN Model
No full textWe take a zero tolerance to any situation where fraudulent research is published in our journals. As a result, this article has been retracted by the Publisher because it is suspected to be a nonsensical computer-generated publication with a number of tortured phrases and irrelevant references.
Additional measures have been implemented to prevent these issues from reoccurring.
EDP Sciences is extremely grateful to anonymous whistleblowers and the Problematic Paper Screene
Galaxy interactions in void substructures: Morphology and stellar populations of two triplets from CAVITY
No full textContext. Cosmic voids, vast, underdense regions of the Universe, serve as unique laboratories for studying galaxy evolution in isolation. Within these voids, galaxy triplets, rare systems of three close galaxies, provide crucial insights into how local interactions shape stellar populations and morphology in the absence of strong environmental perturbations.
Aims. We investigate the spatially resolved stellar populations, morphologies, mass assembly histories, and dynamical properties of six galaxies from the Calar Alto Void Integral-field Treasury surveY (CAVITY). These galaxies reside in two void triplet systems, CAVITY5273X and VGS31.
Methods. We employed integral field unit (IFU) spectroscopy combined with full spectral fitting using the FAD
A group of merging galaxies falling into Abell 2142
No full textGalaxy clusters produce a very hostile environment for galaxies: their gas gets stripped by ram pressure, they undergo galaxy interactions, and their star formation is quenched. Clusters, like Abell 2142, grow not only through galaxy accretion but also through galaxy group infall. Our goal was to study the physical and dynamical state of the most conspicuous infalling group, which is located at a projected distance of 1.3 Mpc from the Abell 2142 centre. The galaxy group G is the leading edge of a spectacular 700 kpc long X-ray tail of hot gas stripped by ram pressure. The infalling galaxies are not quenched yet and are ideal objects for studying the transformation processes due to the cluster environment. We used integral field spectroscopy from MaNGA to derive stellar and gas kinematics, and MegaCam for photometry. Stellar populations (with age and metallicity) were obtained through full-spectrum fitting using NBURST
Analysing the impact of carbon regulation policies on the clean energy advertisement input decision
No full textThis study introduces a novel ceiling constraint on clean energy advertisement input and examines its interaction with two carbon regulation policies—carbon tax (CT) and carbon allowance mechanism (CAM)—in shaping operational decisions. The key findings are as follows: (1) Under a low ceiling, both policies lead to identical advertisement input, yet CT results in lower profits for chain members. Under a moderate or high ceiling, CAM induces higher advertisement input than CT. (2) Regardless of the ceiling level, CAM consistently leads to higher power demand, higher total emissions, and lower conventional power prices compared to CT. (3) When the ceiling constraint is binding, raising it reduces conventional power prices, power demand, and emissions under both policies, while increasing the equilibrium values for other decision variables. Theoretical and managerial contributions: Theoretically, this study advances low-carbon operations modeling by incorporating a regulatory ceiling on advertisement input, offering a refined framework for evaluating carbon policies. It further identifies critical threshold levels (e.g., of the ceiling) that dictate the relative efficacy of CT versus CAM in promoting green input and shaping profitability. From a managerial perspective, the findings offer clear guidance; policymakers can use them to design balanced regulations, while power generators can better select operational strategies under different policy regimes
Rediscovering the lost: eDNA detection of freshwater decapods on Réunion Island
No full textFreshwater ecosystems on tropical oceanic islands host unique biodiversity. On Réunion Island, freshwater decapod crustaceans are key indicators of ecosystem health, yet their distribution and conservation status remain poorly documented. This study aimed to investigate the presence of the endemic prawn Macrobrachium hirtimanus, historically reported but unconfirmed for decades, while producing the first island-wide molecular inventory of freshwater decapods using environmental DNA (eDNA) metabarcoding. Water samples (4 L) were collected from 19 riverine sites, and eDNA was extracted and amplified using mitochondrial 16S rRNA primers validated for crustacean detection, followed by high-throughput sequencing. Bioinformatics analyses yielded 250,545 reads and 198 operational taxonomic units (OTUs), representing diverse amphidromous freshwater, coastal marine, and terrestrial decapods. Species richness was largely uniform across sites, though Rivière des Roches, Sainte-Marie, and Saint-Denis hosted higher diversity. Beta diversity showed strong spatial structuring among watersheds, driven primarily by species turnover. Widespread taxa included Atyoida serrata, Caridina typus, and Macrobrachium australe, while C. henriettae and Halocaridinides sp. were more localized. M. hirtimanus was not detected, consistent with its current absence, though continued targeted surveys are required before any formal reassessment. Overall, this study demonstrates the utility of eDNA metabarcoding for monitoring freshwater biodiversity and informing conservation planning on tropical islands
Strategy for simple, on-site failure analysis: investigating bubbles and burn marks in backsheets of PV modules
No full textWe present a practical, field-deployable workflow for the identification and analysis of localized polymer degradation in photovoltaic modules, observed as bubbles and burn marks in three multi-MWp power plants in Brazil and Germany. The approach combines high-throughput screening—visual inspection, infrared thermography, ultraviolet fluorescence imaging, and serial-number mapping—with selective in-depth analyses of representative modules using electroluminescence, current–voltage measurements, and near-infrared absorption spectroscopy. The workflow enables efficient detection of anomalies across large installations, while confirmatory tests validate root causes on a limited subset. Defects occurred in about 3–4% of inspected modules and were concentrated in the upper and lower cell rows. Although all sites experienced similar partial shading, anomalies appeared only in PET-based backsheets with PVDF or PVF outer layers, highlighting material-dependent susceptibility. No immediate electrical or safety impact was found, but continued monitoring is advised to mitigate future reliability risks. The presented methodology offers a scalable, drone-compatible framework for early-stage field detection of polymer degradation