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Riverine hypoxia, oxygen depletion in flowing waters, poses ecological risk, yet its spatial and temporal dynamics remain poorly characterized. This study presents a novel risk-based spatiotemporal framework for assessing riverine hypoxia across Indian river systems, utilizing 18,976 site-year summary data points (annual minimum, mean, maximum) across 87 sub-basins over 17 years. We conceptualized 'contextual hypoxic risk' as the probability of summary statistics falling below a critical threshold (4.0 mg L⁻¹), distinguishing emerging, intermittent, and perennial hypoxic conditions. Hypoxic risks were estimated under an empirical Bayes (Poisson-Gamma hierarchical framework) to address overdispersion and stabilize standard error. Sub-basin-level aggregation mitigated site selection bias, yielding hydrologically meaningful and analytical units that facilitates policy decision. Of observations, 47% (8914) were emerging hypoxic events, 7% (1328) intermittent, and 1% (190) perennial. At least one severe hypoxic event (DO < 2.0 mg L⁻¹) occurred at approximately 25% of sites-significantly exceeding the global average (12.6%). Spatial analysis revealed pronounced heterogeneity, with hypoxic risk ranging from 0 to 50%, and northwestern and Gangetic sub-basins exhibiting high hypoxic risks and faster intensification. While hypoxic occurrences revealed upward national trend, hypoxic risk showed transient patterns. Space-time interaction analysis indicated statistically significant accelerating risk trajectories-particularly for perennial and intermittent types-across six key sub-basins. By coupling probabilistic risk modelling with spatial smoothing and trajectory steepness diagnostics, this framework quantifies both spatial variability and temporal intensification of riverine hypoxia. The scalable, reproducible framework is applicable to other developing regions. Findings underscore urgent need for adaptive, sub-basin-scale management to prevent progressive establishment of chronic hypoxic regimes in India's river systems.

The results of measurements of the fission cross sections of ²³⁹Pu, ²⁴⁰Pu, and ²⁴²Pu nuclei by neutrons in the energy range from 0.3 to 500 MeV carried out at the GNEIS neutron complex at the Petersburg Nuclear Physics Institute of the National Research Centre “Kurchatov Institute” (PNPI, Gatchina) are presented.

Artificial aging of a (linden) icon board was studied using Raman spectroscopy–microscopy. Chemometric analysis revealed significant changes in the molecular composition and structure of the samples. A model for aging time prediction from Raman spectra was constructed. The proposed methods of analysis can be applied in the restoration of valuable icons.

Silent speech decoding (lip reading) represents an innovative hands-free communication method for individuals with laryngeal and lingual impairments, addressing critical daily communication challenges. Herein, a novel silent speech decoding system is proposed, which employs a self-powered, low-cost, and conformable triboelectric-based E‑skin patch and a well-trained multi-layer convolutional neural network (CNN) model. We systematically characterize the structural principles and electrical performance of the E-skin patch. A comparative analysis of labial kinematics during vocalized and silent speech is also conducted, which demonstrates strong consistency in time-frequency domain characteristics. The utilized CNN model is trained across 15 lexical categories (200 samples per category), achieving a high accuracy of 98.75% and demonstrating excellent recognition performance. Furthermore, by integrating human-machine interaction (HMI) and virtual reality (VR) technologies, we develop three representative applications, including a real-time lip language visualization system, an orofacial-controlled "Feeding Frenzy" interactive game, and a VR communication platform with avatar dialogue. This technology enables barrier-free communication for voiceless populations, demonstrating significant potential in HMI, augmentative communication systems, virtual reality integration, and biomedical rehabilitation.

Background fluctuations of Quantulus 1220 radiometers in radiocarbon laboratories have been investigated. It has been established that fluctuations of the instrumental background in the radiocarbon energy spectrum region depend on variations in the muon flux. The maximum amplitudes are observed during the cold season of the year. Measurements of low-activity samples are recommended to be performed during the warm period of the year.

It turned out to be possible to obtain a solution to the quantum problem of two and three bodies in the semiclassical approximation using the example of hydrogen and helium atoms, as well as hadrons such as the pion, proton, and some resonances in the language of quarks. In the latter case, it was possible to consider a three-quark problem for the proton and to obtain expressions for the wave functions of heavy quarkonium based on Cornell potential.