Universidad Mayor is a private university in Santiago, Chile. It was founded in 1988.
The giant kelp Macrocystis pyrifera is a foundational species in marine coastal ecosystems, yet its microscopic life stages are particularly vulnerable to warming and pollution. We examined its seasonal phenology over an annual cycle initiated under the 2023—2024 El Niño warming at Horcón (central Chile), a coastal site strongly influenced by long-term industrial activity. Sori were collected in austral spring and summer to winter, and in vitro cultures were used to quantify settled spores, germination, gametophyte and sporophyte development, sex ratio, fecundity, and reproductive success. Sea surface temperature (SST) data showed strong seasonal contrasts, with warm anomalies in summer-autumn linked to the coastal El Niño, followed by markedly cooler conditions in winter. Winter cultures, after El Niño waned, reached 220,500 spores cm⁻2, nearly ten times higher than in spring and autumn and twenty times higher than in summer. Germination peaked in winter (96—100
We investigate a cosmological model based on matter creation in a single-component universe, its late time behavior and observational constraints derived from observational data. Furthermore, we explore the equivalence between this framework and interacting dark sector models, which establishes a connection between the matter creation rate and cosmological interactions. We first focus on the case of a constant equation of state parameter, where both known and novel interaction terms naturally emerge from matter creation, numerous of them exhibiting a sign-changeable behavior. The analysis is then extended to a time-dependent equation of state by using dynamical systems techniques.
We model anisotropic neutron stars using three distinct prescriptions for pressure anisotropy-the Horvat, Bowers-Liang, and covariant models-and three equations of state with different particle compositions, each described by a piecewise-polytropic parametrization with continuous sound speed. The stability of these configurations is assessed through their dynamical evolution using a fully nonlinear relativistic code. For stable configurations, we compute the oscillation spectrum and identify the fundamental mode frequency. We found that, while the isotropic and Horvat models become unstable close to the maximum-mass point, the Bowers-Liang and covariant models become unstable at lower central densities, indicating that the standard turning-point criterion may not reliably predict the onset of dynamical instability in anisotropic stars. Based on our results, we also determine the neutral-stability line and verify that configurations lying to the right of this line are indeed unstable under radial perturbations and collapse. Overall, given an equation of state, pressure anisotropy can increase the maximum mass of an stable configuration by up to similar to 30% compared to the isotropic case. It also allows for more compact stable configurations that may collapse on longer timescales once they become unstable. Finally, we show that these compact stars could initially mimic a black hole's gravitational-wave ringdown. However, the production of subsequent echoes is not guaranteed by high compactness; instead, it depends critically on the star's specific internal structure and equation of state.
A complete UHPLC-MS phytochemical profiling of Elettaria cardamomum pod extract was conducted, identifying a dominant terpenoid glycoside (m/z 694.185) alongside flavonoid and phenolic acids that collectively mediate reduction, nucleation, and capping in the green synthesis of CuO nanoparticles (EC:CuO NPs). The resulting EC: CuO NPs exhibited a monoclinic structure with Cu2* oxidation state, diverse morphologies (35-600 nm), and high purity (Cu 74.99 wt%, O 25.01 wt%), as confirmed by XRD, XPS, FESEM/EDS. Significant Methyl Orange (MO) adsorption was observed after optimizing reaction parameters, while ROS-scavenger studies identified photogenerated holes (h*) as the dominant oxidative species, followed by center dot OH and O2-center dot radicals. Under simulated solar irradiation (1 sun), EC:CuO NPs achieved 99 % MO degradation within 90 min, with a quantum yield of 1.60 x 10-4 molecules photon-1 , a space-time yield of 7.98 x 10-6 molecules photon-1 mg-1 , and a rate constant (k) of 0.07332 min-1 . The catalyst retained over 92 % efficiency after four reuse cycles. Agar-well assays demonstrated potent antibacterial activity with inhibition zones of 2.8 cm and 2.6 cm against S. aureus and P. aeruginosa, respectively, attributed by Cu2*-ion release and ROS-mediated membrane disruption. These findings establish EC:CuO NPs as a comprehensively characterized, dual-function material for sustainable dye mineralization and broad-spectrum antimicrobial applications.
