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Understanding the relative contributions of aboveground and belowground processes to soil accretion and carbon density may explain carbon sequestration rates in mangroves across different coastal environmental settings. We reformulated the nutrient mangrove model (NUMAN) by improving algorithms and uncertainty analysis using literature values and site-specific observations to evaluate the relative contributions of organic and inorganic sedimentation for three mangrove sites with marked soil fertility gradients reflected by nitrogen-to-phosphorus (N:P) ratios including Shark River (N:P = 28), Rookery Bay (N:P = 54–78), and Taylor Slough (N:P = 102) in south Florida. NUMAN 2.0 considers cellulose as a refractory organic-matter sub-pool and simultaneously incorporates coarse-root inputs to soil formation. The model simulation also captures root necromass accumulation. Monte Carlo (MC) simulations (N = 1000 per site) were conducted to capture uncertainty by treating five key parameters as random variables: lignin content in fine, coarse, and large roots; inorganic sediment loading; and root biomass at the surface. With robust mass balancing of organic matter, NUMAN 2.0 generates precise predictions of surface accretion and carbon density. NUMAN 2.0 simulations estimated mean (standard deviation) soil carbon sequestration rates at 130.1 (55.4) for Shark River, 72.5 (3.7) for Rookery Bay, and 130.0 (83.9) g m-2 yr-1 for Taylor Slough, compared to field values of 123.0, 86.0, and 108.8 (8.7) g m-2 yr-1 , respectively. Simulation experiments with NUMAN 2.0 suggest that belowground organic matter dominates soil formation and carbon sequestration generally in coastal environmental settings with little allochthonous input such as carbonate settings, while wood litterfall should dominate soil organic matter in top 10 cm in estuaries, and bays. 

In this article, educators across schools tell the story of planning, implementing, and reflecting on an elementary antiracist unit focused on mathematizing racial representation in school libraries. Students and teachers engaged in conversations about race, utilized mathematics to visualize erasures of race in literature, and involved parents, administrators and the community in recognizing and taking action to change this injustice. Our team considers tensions and powerful student thinking involved in using mathematics for antiracist learning for second through fifth-grade children. 

Antiprotons created by laser ionization of antihydrogen are observed to rapidly escape the ALPHA trap. Further, positron plasmas heat more quickly after the trap is illuminated by laser light for several hours. These phenomena can be caused by patch potentials—variations in the electrical potential along metal surfaces. A simple model of the effects of patch potentials explains the particle loss, and an experimental technique using trapped electrons is developed for measuring the electric field produced by the patch potentials. The model is validated by controlled experiments and simulations. 

Double- and single-differential cross sections for inclusive charged-current ${\nu }_{\mu }$-nucleus scattering are reported for the kinematic domain 0 to $2\mathrm{GeV}/c$in three-momentum transfer and 0 to 2 GeV in available energy, at a mean ${\nu }_{\mu }$energy of 1.86 GeV. The measurements are based on an estimated 995,760 ${\nu }_{\mu }$charged-current (CC) interactions in the scintillator medium of the NOvA Near Detector. The subdomain populated by 2-particle-2-hole (2p2h) reactions is identified by the cross section excess relative to predictions for ${\nu }_{\mu }$-nucleus scattering that are constrained by a data control sample. Models for 2-particle-2-hole processes are rated by ${\chi }^2$comparisons of the predicted-versus-measured ${\nu }_{\mu }$CC inclusive cross section over the full phase space and in the restricted subdomain. Shortfalls are observed in neutrino generator predictions obtained using the theory-based València and SuSAv2 2p2h models. Published by the American Physical Society2025 

We report a search for neutrino oscillations to sterile neutrinos under a model with three active and one sterile neutrinos ( $3+1$model). This analysis uses the NOvA detectors exposed to the NuMI beam, running in neutrino mode. The data exposure, $13.6\times {10}^{20}$protons on target, doubles that previously analyzed by NOvA, and the analysis is the first to use ${\nu }_{\mu }$charged-current interactions in conjunction with neutral-current interactions. Neutrino samples in the near and far detectors are fitted simultaneously, enabling the search to be carried out over a $\mathrm{\Delta }{m}_{41}^2$range extending 2 (3) orders of magnitude above (below) $1{\mathrm{eV}}^2$. NOvA finds no evidence for active-to-sterile neutrino oscillations under the $3+1$model at 90% confidence level. New limits are reported in multiple regions of parameter space, excluding some regions currently allowed by IceCube at 90% confidence level. We additionally set the most stringent limits for anomalous ${\nu }_{\tau }$appearance for $\mathrm{\Delta }{m}_{41}^2\le 3{\mathrm{eV}}^2$. Published by the American Physical Society2025 

Abstract Measuring observables to constrain models using maximum-likelihood estimation is fundamental to many physics experiments. Wilks' theorem provides a simple way to construct confidence intervals on model parameters, but it only applies under certain conditions. These conditions, such as nested hypotheses and unbounded parameters, are often violated in neutrino oscillation measurements and other experimental scenarios. Monte Carlo methods can address these issues, albeit at increased computational cost. In the presence of nuisance parameters, however, the best way to implement a Monte Carlo method is ambiguous. This paper documents the method selected by the NOvA experiment, the profile construction. It presents the toy studies that informed the choice of method, details of its implementation, and tests performed to validate it. It also includes some practical considerations which may be of use to others choosing to use the profile construction.