Woodlice, as one of the key groups, contribute to the decomposition of litter in ecosystems. However, the resource use by woodlice, which likely depends on the body size and developmental stage, remains poorly understood. Understanding ontogenetic shifts in the composition of stable isotopes δ13C and δ15N is essential for assessing the position of woodlice in soil food webs. We applied the stable isotope analysis of carbon and nitrogen to four ontogenetic stages of two synanthropic cosmopolitan woodlice species, Cylisticus convexus and Oniscus asellus, along with their potential food resources in a city park in Moscow, Russia. We compared mancas, juveniles, young adults, and adults. In C. convexus, the δ13C values remained constant, while juveniles, young adults and adults were enriched in 15N compared to mancas. In O. asellus, δ13C values remained constant except for the last age (adults), when they were enriched in 13C by about 1.5‰, compared to other ages. Young adults of O. asellus were depleted in 15N compared to other ages. Bayesian mixing models (MixSIAR) indicated leaf litter as the primary dietary resource for both species, with species-specific differences in the contribution of fungi and moss. These results suggest ontogenetic shifts in resource use within woodlice populations. We demonstrate the need to consider the age of woodlice when interpreting isotopic data and assessing their trophic roles in soil ecosystems.
We show that, in order to classify Hopf algebra (co)actions on a given finite dimensional algebra up to equivalence, one should start with the classification of the possible cosupports (i.e. the sets of linear operators by which H & lowast; is acting) of Hopf algebra coactions and then consider dual Hopf algebra actions. As an application, we classify quantum symmetries of the set of two points and the algebra of dual numbers. In addition, we show that the straight line does not admit an (ungraded) universal coacting Manin Hopf algebra. Moreover, we prove that for n 14 the full matrix algebra Mn(k) admits a nontrivial Hopf algebra coaction such that all Hopf algebra actions with the same restriction on the cosupport are trivial, i.e. the cosupport may reduce under the dualization and a finite dimensional algebra may have less equivalence classes of actions than coactions. Simultaneously, for any n 14, we define an elementary grading on Mn(k) by an infinite group that cannot be regraded by any finite group. (The previously known lower bound was n 349.) (c) 2026 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Catalytic methane combustion is an efficient way to remove methane from the exhaust of natural gas vehicles and mine ventilation streams, thereby mitigating its strong greenhouse impact and reducing the fire and explosion hazards. The most widely used catalysts for methane combustion are high-surface-area oxide supports with palladium-based nanoparticles. The promotion of Pd by noble and transition metals is one of the most effective strategies to enhance long-term stability of the catalytic nanoparticles. Here, in search of a synthetic approach to localize promoters in the vicinity of active sites, we systematically compare ternary Pd-Pt-Ni/Al2O3 catalysts with simultaneous addition of Pt and Ni promoters prepared via wet impregnation and colloidal synthesis. The efficient incorporation of promoters into the active phase, Pd1_ xPtxO nanoparticles, is achieved only for the catalyst prepared via colloidal synthesis. Contrary, in addition to Pd1_ xPtxO nanoparticles, wet impregnation results in the growth of Pt-enriched metal nanoparticles, whereas Ni is distributed uniformly over the Al2O3 support with the formation of NiAl2O4 phase. An innovative microcalorimetric approach was used to evaluate catalytic performance. Microcalorimetry showed that the Pd-Pt-Ni/Al2O3 catalyst obtained by wet impregnation has higher initial methane combustion activity, owing to larger, more easily reducible Pd1_ xPtxO nanoparticles. By contrast, the Pd-Pt-Ni/Al2O3 catalyst prepared using colloidal synthesis exhibits significantly greater long-term stability, which is caused by the promotion effect of Pt and Ni. These findings highlight the high potential of colloidal nanoparticles containing one or more promoters for the preparation of highly stable and highly active methane combustion catalysts.
Mature, isolated neutron stars can accrete from the interstellar medium. Due to turbulence, the accreted gas can have a substantial angular momentum and form a disc around the compact object. In this paper, we perform a population synthesis of isolated neutron stars in the Milky Way that specifically tracks the possibility of disc formation, which typically requires a low spatial velocity of the compact object (≲ 40 km s^-1). In general, weak magnetic fields favour disc formation as the magnetosphere occupies a smaller volume. Still, even in the case of fields decaying exponentially over a characteristic timescale of ∼ 1.5 Gyr, we find that for several realistic models of propeller spin-down, only a small fraction of accretors (down to ∼ 0.02
The spectrum of a graph G is the set of the eigenvalues of its adjacency matrix. It turns out that one can say a lot about a graph with the only knowledge being the spectrum of this graph. In this paper we obtain new results about the spectrum of G(n, αn, α^2 n) graphs. We then apply these results to get a giant component theorem for them.
