Soluble microbial products (SMP) formed by microorganisms in wastewater treatment plants (WWTPs) adversely affect final effluent quality and treatment efficiency. It is difficult to distinguish SMP from residual proteins, lipids and carbohydrates present in the influent that may persist during treatment. No method is currently available to determine quantitatively the extent to which SMP contribute to organic discharges from municipal WWTPs. In this work a modeling approach is presented which allows the SMP fraction of the effluent of a municipal WWTP to be quantified and described. The model is validated, in terms of utilization-associated products, biomass-associated products and extracellular polymeric substances, using influent from a municipal WWTP. SMP was found to account for, on average, 27 mg/L of chemical oxygen demand (COD), or 61% of the total COD in the WWTP effluent. Over 90% of the SMP was comprised of biomass-associated products. Five main factors influencing SMP formation in WWTP were evaluated. Neither wastewater composition nor mixed liquor suspended solids concentration was found to affect SMP production. On the other hand, a positive correlation was observed for SMP formation with both solids retention time and influent COD concentration, and a negative correlation with hydraulic retention time. Thus, operating or designing WWTPs with short solids retention and long hydraulic retention times could be considered as solutions for minimizing SMP production.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.watres.2015.10.065 | DOI Listing |
Contemp Clin Trials Commun
February 2025
Center for Health Outcomes and Interdisciplinary Research, Department of Psychiatry, Massachusetts General Hospital, United States.
Background: Chronic emotional distress among cardiac arrest (CA) survivors and their caregivers is prevalent and worsens quality of life and recovery. Interventions to prevent chronic distress post-CA are needed. We developed (RT-CA), an intervention to increase resiliency in CA survivor-caregiver dyads (pairs).
View Article and Find Full Text PDFBiomater Sci
January 2025
Department of Nanobiomedical Science & BK21 FOUR micropatterned shape-memory NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 31116, Republic of Korea.
A scaffold design for tendon regeneration has been proposed, which mimics the microstructural features of tendons and provides appropriate mechanical properties. We synthesized a temperature-triggered shape-memory polymer (SMP) using the ring-opening polymerization of polycaprolactone (PCL) with polyethylene glycol (PEG) as a macroinitiator. We fabricated a micropatterned patch using SMP capillary force lithography, which mimicked a native tendon, for providing physical cues and guiding effects.
View Article and Find Full Text PDFAdv Healthc Mater
January 2025
Department of Otorhinolaryngology-Head and Neck Surgery, Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, P. R. China.
Noise-induced hearing loss (NIHL) results from prolonged exposure to intense noise, causing damage to sensory outer hair cells (OHCs) and spiral ganglion neurons (SGNs). The blood labyrinth barrier (BLB) hinders systemic drug delivery to the inner ear. This study applied a retro-auricular round window membrane (RWM) method to bypass the BLB, enabling the transport of macromolecular proteins into the inner ear.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an 710069, China.
Late embryogenesis abundant (LEA) proteins are a class of proteins associated with osmotic regulation and plant tolerance to abiotic stress. However, studies on the gene family in the alpine cold-tolerant herb are still limited, and the phylogenetic evolution and biological functions of its family members remain unclear. In this study, we conducted genome-wide identification, phylogenetic evolution, and abiotic stress response analyses of family genes in species, alpine cold-tolerant medicinal herbs in the Qinghai-Tibet Plateau and adjacent regions.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Submerged plants (SMPs) play a critical role in improving water quality and reducing NO greenhouse gas emissions. However, freshwater salinization represents a major environmental challenge in aquatic systems. To investigate the impact of salinization on NO emissions, this study conducted indoor mesocosm experiments simulating SMP and nonsubmerged plant (Non_SMP) areas in freshwater lakes.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!