We propose the use of Bayesian hierarchical/multilevel ratio approach to estimate the annual riverine phosphorus loads in the Saginaw River, Michigan, from 1968 to 2008. The ratio estimator is known to be an unbiased, precise approach for differing flow-concentration relationships and sampling schemes. A Bayesian model can explicitly address the uncertainty in prediction by using a posterior predictive distribution, while in comparison, a Bayesian hierarchical technique can overcome the limitation of interpreting the estimated annual loads inferred from small sample sizes by borrowing strength from the underlying population shared by the years of interest. Thus, by combining the ratio estimator with the Bayesian hierarchical modeling framework, long-term loads estimation can be addressed with explicit quantification of uncertainty. Our study results indicate a slight decrease in total phosphorus load early in the series. The estimated ratio parameter, which can be interpreted as flow-weighted concentration, shows a clearer decrease, damping the noise that yearly flow variation adds to the load. Despite the reductions, it is not likely that Saginaw Bay meets with its target phosphorus load, 440 tonnes/yr. Throughout the decades, the probabilities of the Saginaw Bay not complying with the target load are estimated as 1.00, 0.50, 0.57 and 0.36 in 1977, 1987, 1997, and 2007, respectively. We show that the Bayesian hierarchical model results in reasonable goodness-of-fits to the observations whether or not individual loads are aggregated. Also, this modeling approach can substantially reduce uncertainties associated with small sample sizes both in the estimated parameters and loads.
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http://dx.doi.org/10.1016/j.watres.2010.03.008 | DOI Listing |
Sci Rep
January 2025
Guizhou Energy Group Co., Ltd., Guiyang, 550081, Guizhou, China.
To investigate the statistical laws of acoustic emission energy (AEE) avalanche dynamics of sandstone under varying fracture lengths and dip angles, as well as to determine the relationship between acoustic emission (AE) parameters and damage variables, we studied the mechanical properties and AE characteristics of sandstone with a single fracture subjected to uniaxial compression with the aid of the Shimadzu AG-IS test system and the PCI-2 AE system. The AEE characteristics of fractured sandstone under load were analyzed based on the statistical method of avalanche dynamics, with emphasis on AEE distribution, aftershock sequence, and waiting time distribution. The Weibull distribution function that incorporates a correction coefficient β was employed to optimize the Weibull parameters based on the strain equivalent hypothesis theory, which led to the establishment of a statistical damage constitutive model for fractured rock.
View Article and Find Full Text PDFDokl Biochem Biophys
January 2025
Department of Orthopaedics, Affiliated Hospital of Hebei University, 071000, Baoding, China.
Unlabelled: Osteoporosis is a condition where bones weaken due to a loss in density and quality, making them fragile and more susceptible to fractures, even from minor stress or injury. In this experimental study, we scrutinized the antiosteoporosis effect of phyllanthin against glycocorticoid (GIOP) induced osteoporosis in rats.
Methods: : SD rats were used in this study and subcutaneous administration of DEX (3 mg/kg) was used for the induction of osteoporosis and rats were treated with phyllanthin and alendronate for 12 weeks.
Environ Res
January 2025
Key Lab of Northwest Water Resource, Environment, and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
Controlling runoff pollution is crucial to improving ecological environments in the context of urbanization and climate change. However, a significant research gap remains in the treatment and reuse of roof runoff, particularly during the first flush. To address this, a novel dry-wet polymorphic constructed wetland (DWP-CW) system was developed to purify first flush runoff efficiently and reliably.
View Article and Find Full Text PDFNat Plants
January 2025
National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.
Arabidopsis PHOSPHATE 1 (AtPHO1) and its closest homologue AtPHO1;H1 are phosphate transporters that load phosphate into the xylem vessel for root-to-shoot translocation. AtPHO1 and AtPHO1;H1 are prototypical members of the unique SPX-EXS family, whose structural and molecular mechanisms remain elusive. In this study, we determined the cryogenic electron microscopy structure of AtPHO1;H1 binding with inorganic phosphate (Pi) and inositol hexakisphosphate in a closed conformation.
View Article and Find Full Text PDFJ Contam Hydrol
January 2025
USDA ARS, National Soil Erosion Research Laboratory, West Lafayette, IN 47907, United States of America.
Agricultural phosphorus (P) losses may result from either recently applied fertilizers or from P accumulated in soil and sediment. While both P sources pose an environmental risk to freshwater systems, differentiating between sources is crucial for identifying and implementing management practices to decrease loss. In this study, laboratory rainfall simulations were completed on runoff boxes and undisturbed soil columns before and after fertilizer application.
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