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The membraneless-gas separation microfluidic paper-based analytical device (ML-GS μPAD), consisting of donor, spacer, and acceptor layers, was developed to monitor total ammonia in fish pond water. The principle of the analysis involved the addition of sodium hydroxide solution to the sample zone in the donor layer containing ammonia/ammonium, and the produced ammonia gas diffuses through the spacer to the detection zone in the acceptor layer containing red rose extract to produce a color change from pink to blue corresponding to the ammonia/ammonium concentration. Under optimum conditions, the proposed method provided good linearity of ammonia in the range concentration of 0-100 mg L -1 (R 2  = 0.9993) with LOD and LOQ of 2.25 and 7.51 mg L -1 , respectively. This method was successfully applied to fish pond water samples without significant influence of interfering compounds with recoveries in the range of 103-110%, indicating good selectivity and accuracy of the proposed method., (© 2022. The Author(s), under exclusive licence to The Japan Society for Analytical Chemistry.)

Most of the on-site approaches for inferring of the post-mortem interval are still based on observative data from the direct body inspection, whereas, objective and quantitative analyses, such as potassium in the vitreous humor, are require laboratory instrumentation and skilled personnel. The present paper presents a simple and low cost analytical method suitable for use at the crime scene for inferring the time since death. The method uses a microfluidic paper-based device (μPAD) for the determination of ammonium in the vitreous humor (VH) based on the selective interaction between the ammonium and the Nessler's reagent. The color change was measured in terms of "RGB distance" by using a simple and free smartphone application. The optimized device showed a limit of detection of 0.4 mmol L -1 , with between days precision less than 9.3% expressed as relative standard deviation, and accuracy between days from 94.5% to 104.5%. The selectivity of the Nessler's reaction was tested towards the main vitreous humor compounds, and no significant interferences were found. This paper-based analytical device was successfully used for the determination of ammonium ion in VH samples from forensic autopsies. The results obtained with the proposed method, although for a limited number of cases (n = 25), showed a close correlation with the data obtained with an instrumental analysis based on capillary electrophoresis. Moreover, in order to make the evaluation of results as simple as possible, a direct correlation between the color intensity, expressed as RGB distance, and the post-mortem interval was studied and a significant correlation was found (R 2  > 0.78). In conclusion, the present preliminary study showes that the proposed device could be an additional tool to the traditional methods for a more accurate, although still presumptive, estimation of the time of death directly at the crime scene., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Suzuki-Miyaura cross-coupling is one of the most powerful strategies for constructing biaryl compounds. However, classic Suzuki-Miyaura coupling suffers from hour-scale reaction time and competitive protodeboronation. To address these problems, a mild nonaqueous potassium trimethylsilanolate (TMSOK)-assisted Suzuki-Miyaura coupling strategy was designed for the microsynthesis of biaryls in paper spray ionization (PSI). Due to the acceleration power facilitated by microdroplet chemistry in reactive PSI, the microsynthesis of biaryls by reactive PSI was accomplished within minutes with comparable yields to the bulk, showing good substrate applicability from 32 Suzuki-Miyaura reactions of aryl bromides and aryl boronic acid/borates bearing different substituents. Based on the above TMSOK-assisted Suzuki-Miyaura coupling strategy, we further developed a high-sensitivity and selective PSI mass spectrometry (MS) method for quantitative analysis of aryl bromides, a class of environmentally persistent organic pollutants that cannot be directly detected by ambient mass spectrometry due to their low ionization efficiency. In situ derivatization of aryl bromides was achieved with aryl borates bearing quaternary ammonium groups in PSI. The proposed PSI-MS method shows good linearity over the 0.01-10 μmol L -1 range with low detection limits of 1.8-4.8 nmol L -1 as well as good applicability to the rapid determination of six aryl bromides in three environmental water samples. The proposed PSI-MS method also shows good applicability to brominated flame retardants (polybrominated diphenyls/diphenyl esters). Overall, this study provides a simple, rapid, low-cost, high-sensitivity, and high-selectivity strategy for trace aryl bromides and other brominated pollutants in real samples with minimal/no sample pretreatment.

Lignosulfonates are important by-products of the paper industry and may be transformed into different commodities. We studied the molecular properties of ammonium (LS-AM) and calcium Lignosulfonates (LS-C) and evaluated their bioactivity towards the early development of maize plantlets. The FT-IR, 13 C NMR and 1 H- 13 C-HSQC-NMR spectra showed that the two lignosulfonates varied in hydroxyl, sulfonate and phenolic content, while DOSY-NMR spectroscopy suggested a similar diffusivity. High Performance Size Exclusion Chromatography (HPSEC) was used to simulate the effects of root-exuded acids and describe the conformational dynamics of both LS substrates in acidic aqueous solutions. This technique showed that LS-C was stabilized by the divalent Ca 2+ counterion, thus showing a greater conformational stability than LS-AM, whose components could not be as efficiently aggregated by the monovalent NH4 + counter-ion. The plant bioassays revealed that LS-AM enhanced the elongation of the root system, whereas LS-C significantly increased both total and shoot plant weights. We concluded that the lignosulfonate bioactivity on plant growth depended on the applied concentrations, their molecular properties and conformational stability., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Amino acid L-arginine (Arg), usually presented in food products and biological liquids, can serve both as a useful indicator of food quality and an important biomarker in medicine. The biosensors based on Arg-selective enzymes are the most promising devices for Arg assay. In this research, three types of amperometric biosensors have been fabricated. They exploit arginine oxidase (ArgO), recombinant arginase I (ARG)/urease, and arginine deiminase (ADI) coupled with the ammonium-chelating redox-active nanoparticles. Cadmium-copper nanoparticles (nCdCu) as the most effective nanochelators were used for the development of ammonium chemosensors and enzyme-coupled Arg biosensors. The fabricated enzyme/nCdCu-containing bioelectrodes show wide linear ranges (up to 200 µM), satisfactory storage stabilities (14 days), and high sensitivities (A⋅M -1 ⋅m -2 ) to Arg: 1650, 1700, and 4500 for ADI-, ArgO- and ARG/urease-based sensors, respectively. All biosensors have been exploited to estimate Arg content in commercial juices. The obtained data correlate well with the values obtained by the reference method. A hypothetic scheme for mechanism of action of ammonium nanochelators in electron transfer reaction on the arginine-sensing electrodes has been proposed., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Purpose: Olfactory dysfunction (OD) can be a long-term consequence of various viral infections, including COVID-19. Dysfunction includes hyposmia/anosmia and parosmia (odor distortions). Interactions of the virus with the olfactory nerve have been extensively researched, but little is known about the interactions of the intranasal trigeminal nerve system in modulating this sensory loss., Methods: We investigated intranasal trigeminal function across COVID-19 OD patients with and without parosmia compared to normosmic controls, to determine whether (1) post-viral hyposmia and/or (2) post-viral hyposmia with parosmia is associated with altered trigeminal function. OD patients (n = 27) were tested for olfactory function using the extended Sniffin' Sticks olfactory test and for trigeminal function through three methods-odor lateralization, subjective ratings of nasal patency, and ammonium vapor pain intensity ratings. This group was subsequently compared to controls, normosmic subjects (n = 15)., Results: Our findings revealed that post-COVID OD patients without parosmia experienced decreased sensitivity in ammonium vapor pain intensity ratings and odor lateralization scores-but similar nasal patency ratings-compared to normosmic controls. There were no significant differences in trigeminal function between OD patients with and without parosmia., Conclusions: Based on our results, we conclude that the trigeminal nerve dysfunction may partially explain post-viral OD, but does not seem to be a major factor in the generation of parosmia pathophysiology., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Diatoms can survive long periods in dark, anoxic sediments by forming resting spores or resting cells. These have been considered dormant until recently when resting cells of Skeletonema marinoi were shown to assimilate nitrate and ammonium from the ambient environment in dark, anoxic conditions. Here, we show that resting cells of S. marinoi can also perform dissimilatory nitrate reduction to ammonium (DNRA), in dark, anoxic conditions. Transmission electron microscope analyses showed that chloroplasts were compacted, and few large mitochondria had visible cristae within resting cells. Using secondary ion mass spectrometry and isotope ratio mass spectrometry combined with stable isotopic tracers, we measured assimilatory and dissimilatory processes carried out by resting cells of S. marinoi under dark, anoxic conditions. Nitrate was both respired by DNRA and assimilated into biomass by resting cells. Cells assimilated nitrogen from urea and carbon from acetate, both of which are sources of dissolved organic matter produced in sediments. Carbon and nitrogen assimilation rates corresponded to turnover rates of cellular carbon and nitrogen content ranging between 469 and 10,000 years. Hence, diatom resting cells can sustain their cells in dark, anoxic sediments by slowly assimilating and respiring substrates from the ambient environment., (© 2024 The Authors. Environmental Microbiology published by John Wiley & Sons Ltd.)

Coral reef ecosystems are now commonly affected by major climate and disease disturbances. Disturbance impacts are typically recorded using reef benthic cover, but this may be less reflective of other ecosystem processes. To explore the potential for reef water-based disturbance indicators, we conducted a 7-year time series on US Virgin Island reefs where we examined benthic cover and reef water nutrients and microorganisms from 2016 to 2022, which included two major disturbances: hurricanes Irma and Maria in 2017 and the stony coral tissue loss disease outbreak starting in 2020. The disease outbreak coincided with the largest changes in the benthic habitat, with increases in the percent cover of turf algae and Ramicrusta, an invasive alga. While sampling timepoint contributed most to changes in reef water nutrient composition and microbial community beta diversity, both disturbances led to increases in ammonium concentration, a mechanism likely contributing to observed microbial community shifts. We identified 10 microbial taxa that were sensitive and predictive of increasing ammonium concentration. This included the decline of the oligotrophic and photoautotrophic Prochlorococcus and the enrichment of heterotrophic taxa. As disturbances impact reefs, the changing nutrient and microbial regimes may foster a type of microbialization, a process that hastens reef degradation., (© 2024 The Authors. Environmental Microbiology published by John Wiley & Sons Ltd.)

Algal blooms are increasing worldwide, driven by elevated nutrient inputs. However, it is still unknown how tropical benthic algae will respond to heatwaves, which are expected to be more frequent under global warming. In the present study, a multifactorial experiment was carried out to investigate the potential synergistic effects of increased ammonium inputs (25 μM, control at 2.5 μM) and a heatwave (31°C, control at 25°C) on the growth and physiology (e.g., ammonium uptake, nutrient assimilation, photosynthetic performance, and pigment concentrations) of two bloom-forming algal species, Cladophoropsis sp. and Laurencia sp. Both algae positively responded to elevated ammonium concentrations with higher growth and chlorophyll a and lutein concentrations. Increased temperature was generally a less important driver, interacting with elevated ammonium by decreasing the algaes' %N content and N:P ratios. Interestingly, this stress response was not captured by the photosynthetic yield (Fv/Fm) nor by the carbon assimilation (%C), which increased for both algae at higher temperatures. The negative effects of higher temperature were, however, buffered by nutrient inputs, showing an antagonistic response in the combined treatment for the concentration of VAZ (violaxanthin, antheraxanthin, zeaxanthin) and thalli growth. Ammonium uptake was initially higher for Cladophoropsis sp. and increased for Laurencia sp. over experimental time, showing an acclimation capacity even in a short time interval. This experiment shows that both algae benefited from increased ammonium pulses and were able to overcome the otherwise detrimental stress of increasingly emerging temperature anomalies, which provide them a strong competitive advantage and might support their further expansions in tropical marine systems., (© 2024 The Authors. Journal of Phycology published by Wiley Periodicals LLC on behalf of Phycological Society of America.)

The effectiveness of wetlands in sequestering nutrients and improving water quality relies on a suite of abiotic and biotic conditions. To more fully understand the restraints on nutrient removal, especially salinity and plant cover, we created field-scale mesocosms and monitored nutrient sequestration with nutrient additions and isotopic pool dilutions over 2 years in two wetlands near the Great Salt Lake in Utah. Surprisingly, we found no differences in nutrient removal with plant removal, increased salinity, and altered ambient nutrient concentrations, suggesting functional redundancy in associated primary producers. When submerged aquatic vegetation was removed, chlorophyll α concentration (0.1-9.0 μg/L) increased while nitrogen (N) and phosphorus (P) assimilation remained the same as phytoplankton occupied the open niche space. We did find ammonium concentrations to be inversely related to nitrate assimilation-as the ammonium concentration increased, nitrate assimilation decreased, suggesting preferential uptake of ammonium. Last, in our high N and P treatment mesocosms, the nitrate dramatically declined from 43.9 mg/L to background levels (<0.1 mg/L) within 1 week, showing a high potential for N remediation in these wetlands., (© 2023 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Soil acidification is common in some Chinese tea plantations, which seriously affected growth of tea trees. Hence, it is essential to explore soil remediation in acidified tea plantations for sustainable development of the tea industry. We sought to determine how different fertilizers affect acidified soil and their N transformation in tea plantations. Different fertilizers were used on acidified tea plantation soils for 4 years (2017-2021), and changes in soil pH, indices related to soil N transformation and tea yield were analysed to construct interaction networks of these indices and find which had the largest influence on fertilization. Long-term use of sheep manure reduced soil acidification, increased soil pH, enhanced the number and intensity of N-fixing and ammonifying bacteria, urease, protease, asparaginase and N-acetamide glucose ribosidase activity and nifH gene expression. This treatment reduced the number and intensity of soil nitrifying and denitrifying bacteria, nitrate reductase and nitrite reductase activity, while the expression of amoA-AOA, nirK, nirS, narG and nosZ in turn increased ammonium N content of the soil, reduced nitrate N content, and enhanced tea yield. Topsis index weight analysis showed that ammonium N content in the soil had the largest impact among fertilization effects. Long-term use of sheep manure was beneficial in restoring the balance of the micro-ecosystem in acidified soil. This study provides an important practical basis for soil remediation and fertilizer management in acidified tea plantation soils., (© 2023 German Society for Plant Sciences and the Royal Botanical Society of the Netherlands.)

Surfactants are one of the materials recommended for the cleaning of movable cultural properties. These substances are widespread in other fields - medicine, cosmetics, household appliance industry, etc. Quaternary ammonium compounds are particularly prevalent due to their cleansing and disinfectant properties. Initial studies have shown that surfactants, including quaternary ammonium compounds, have a positive effect on preserved/restored cultural properties. Using relatively low concentrations of aqueous solutions of these substances, it is possible to obtain sufficiently good results to wash out from the restoration of the document or textiles dirt, acidification of the object and colour changes that cause aging and decomposition processes - hydrolysis and oxidation. [ABSTRACT FROM AUTHOR]

This research examined the feasibility of raw fermentate for mainstream partial denitrification-anammox (PdNA) in a pre-anoxic integrated fixed-film activated sludge (IFAS) process. Fermentate quality sampled from a full-scale facility was highly dynamic, with 360-940 mg VFA-COD/L and VFA/soluble COD ratios ranging from 24% to 48%. This study showed that PdNA selection could be achieved even when using low quality fermentate. Nitrate residual was identified as the main factor driving the PdN efficiency, while management of nitrate conversion rates was required to maximize overall PdNA rates. AnAOB limitation was never observed in the IFAS system. Overall, this study showed PdN efficiencies up to 38% and PdNA rates up to 1.2 ± 0.7 g TIN/m 2 /d with further potential for improvements. As a result of both PdNA and full denitrification, this concept showed the potential to save 48-89% methanol and decrease the carbon footprint of water resource recovery facilities (WRRF) by 9-15%. PRACTITIONER POINTS: Application of PdNA with variable quality fermentate is feasible when the nitrate residual concentration is increased to enhance PdN selection. To maximize nitrogen removed through PdNA, nitrate conversion rates need enhancement through optimization of upstream aeration and PdN control setpoints. The IFAS PdNA process was never anammox limited; success depended on the degree of PdN achieved to make nitrite available. Application of PdNA with fermentate can yield 48-89% savings in methanol or other carbon compared with conventional nitrification and denitrification. Integrating PdNA upstream from polishing aeration and anoxic zones guarantees that stringent limits can be met (<5 mg N/L)., (© 2022 Water Environment Federation.)

A new starch-based adhesive with high solid content, high binding force, and low viscosity was prepared via hydrolysis of cassava starch with α-amylase using glycerol as a plasticizer and Ammonium Zirconium Carbonate (AZC) as a crosslinker. The adhesive was applied to coated paper as a partial substitute for SBR latex. The effects of α-amylase, glycerol, AZC, and temperature on the starch adhesive and its performance in application were investigated. The prepared crosslinking cassava starch adhesive showed a significant effect when the starch slurry concentration was 50% (w/w), the dosages of glycerol and α-amylase were 15% and 0.075%, respectively, and the enzymolysis starch was crosslinked with 12% AZC at 50 °C. The modified starch improved the paper in terms of surface strength, gloss, whiteness, and smoothness when 20% SBR latex was substituted into the coating formulation. Statistical analysis indicated that the crosslinking temperature and AZC had significant effects on the performance of the paper, while glycerin and α-amylase had little effect on it. Spectral analysis of the product showed that the crosslinking reaction took place between AZC and cassava starch. The average particle size was 528.6 nm. Scanning Electron Microscope (SEM) images of the paper surface were consistent with the other measured surface properties. [ABSTRACT FROM AUTHOR]

While it is recognized that groundwater contaminant plumes can impact surface waters, there remains little information on the magnitude, spatial extent, and especially temporal variability of the resulting exposure to the variety of aquatic organisms, particularly for stagnant surface waters (e.g., ponds). The present study of a historic landfill plume discharging to a pond investigated contaminant exposure to multiple aquatic zones (endobenthic, epibenthic, pelagic) over approximately 1 year within a temperate climate. Landfill tracers included the artificial sweetener saccharin, ammonium, chloride, and specific conductance. Sampling of pond sediment porewater (upwelling groundwater) and continuous geophysical imaging of the subsurface showed a relatively stable plume footprint covering approximately 26% of the pond, although with spatially varying leachate composition, revealing year-round exposure to endobenthic (within sediments) organisms. Substantial and variable contaminant exposure to epibenthic organisms within the plume footprint was shown by elevated specific conductance measured directly above the sediment interface. Exposure varied daily at times and increased through winter to values representing undiluted plume groundwater. Exposure to pelagic organisms (overlying water) covered a larger area (~50%) due to in-pond circulation. The stream outlet concentrations were stable at approximately 10 times dilution for chloride and saccharin, but were substantially less in summer for ammonium due to in-pond processes. Whereas groundwater contaminants are typically assumed elevated at base flows, the outlet stream contaminant mass discharges to downstream receptors were notably higher in winter than summer, following stream flow patterns. Insights from the present study into the timings and locations of contaminant plume exposure to multiple ecological zones of a pond can provide guidance to contaminated site and aquatic ecosystem managers on improved monitoring, assessment, and remediation protocols. Environ Toxicol Chem 2023;42:1667-1684. © 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada., (© 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.)

The atom- and step-efficient synthesis of chiral fused tricyclic lactams from readily available ketoesters using cheap ammonium salts as the nitrogen source is reported. This ruthenium-catalyzed system operates through an efficient tandem dynamic kinetic asymmetric reductive amination (ARA)/lactamization and produces chiral fused tricyclic lactams in high yields with excellent diastereo- and enantioselectivity (up to >99 % ee, >20 : 1 dr and 98 % yield). The robust method was also applied to the concise synthesis of key intermediates in the synthesis of rivastigmine analogues and chiral N-heterocyclic carbene catalysts., (© 2023 Wiley-VCH GmbH.)

The nitrogen isotopic composition of organic matter is controlled by metabolic activity and redox speciation and has therefore largely been used to uncover the early evolution of life and ocean oxygenation. Specifically, positive δ 15 N values found in well-preserved sedimentary rocks are often interpreted as reflecting the stability of a nitrate pool sustained by water column partial oxygenation. This study adds much-needed data to the sparse Paleoarchean record, providing carbon and nitrogen concentrations and isotopic compositions for more than fifty samples from the 3.4 Ga Buck Reef Chert sedimentary deposit (BRC, Barberton Greenstone Belt). In the overall anoxic and ferruginous conditions of the BRC depositional environment, these samples yield positive δ 15 N values up to +6.1‰. We argue that without a stable pool of nitrates, these values are best explained by non-quantitative oxidation of ammonium via the Feammox pathway, a metabolic co-cycling between iron and nitrogen through the oxidation of ammonium in the presence of iron oxides. Our data contribute to the understanding of how the nitrogen cycle operated under reducing, anoxic, and ferruginous conditions, which are relevant to most of the Archean. Most importantly, they invite to carefully consider the meaning of positive δ 15 N signatures in Archean sediments., (© 2023 The Authors. Geobiology published by John Wiley & Sons Ltd.)

Nutrient pollution has a diverse impact on the environment and human health. The presence of nutrients, such as ammonium and phosphate, is ubiquitous in the environment due to their extensive use in agricultural land and leaching through non-point sources. In this context, biochar-based composites could play an essential role in improving the soil's nutrient retention capacity. The present study aims to develop bentonite-biochar composites (BNT@BC 400 and 600) and utilize them as an ameliorating material in the coal mine degraded soil to reduce the leaching of ammonium and phosphate ions. The bentonite-biochar composite (BNT@BC 400 and 600) was synthesized using the pristine rice straw-derived biochar using the solvothermal method. The biochar was produced at two different pyrolytic temperatures, 400 °C and 600 °C, and denoted as BC 400 and 600, respectively. Hence, the bentonite-biochar composite was denoted as BNT@BC 400 and 600. The BNT@BC 400 and 600 were characterized using the elemental, proximate, SEM, XRD, and FTIR analysis. Subsequently, the BNT@BC composites were evaluated for the adsorptive removal of NH 4 + and PO 4 3- ions using batch adsorption and column leaching studies. In the soil columns, the BNT@BC 400 and 600 were mixed with the soil at two different application rates, viz. 1 and 2.5% (w/w). The leaching characteristics data were fitted using three different fixed-bed models to predict the maximum adsorption capacity of the amended soil columns and the dominant mechanism of adsorption. Results indicated that the BNT@BC 600 showed the maximum adsorption capacity of 33.77 and 64.23 mg g -1 for the adsorption of NH 4 + and PO 4 3- ions, respectively. The dominant adsorption mechanisms in the aqueous solution were the electrostatic attraction, complexation, ion exchange, and precipitation processes. In the soil columns, the sorption of NH 4 + and PO 4 3- ions was governed by diffusive mass transfer and electrostatic interaction. Findings of the study indicated that incorporating the BNT@BC composite in the soil can significantly reduce the leaching of the NH 4 + and PO 4 3- ions and increase the overall soil fertility., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Wastewater treatment plants (WWTPs) play an important role in protecting the quality of water sources. The optimum operation of WWTPs in response to continuous changes in the characteristics of the influent of the WWTP is very important, and it can improve the quality of the effluent of the WWTP. In this study, an approach for optimal operation of the WWTP has been presented considering the quantitative and qualitative variables of influent. In the proposed method, first, the simulation model of WWTP is developed and calibrated using the recorded data of its influent and effluent characteristics as well as operation conditions. Then, the influent is classified into clusters quantitatively and qualitatively k-means clustering method. In the final step, after determining the effective operation parameters, the AMOEA-MAP optimization algorithm is used to determine the optimal values of operation parameters for each cluster of influents based on its quantitative and qualitative characteristics including flow rate, COD, ammonium, and temperature. The proposed approach was implemented on a WWTP in the South of Tehran, the capital of Iran. Dissolved oxygen (DO) in the aeration tank, waste-activated sludge flow rate (Q WAS ) and the ratio of the supernatant flow rate of the sludge dewatering unit to the effluent flow rate (Q d /Q e ) were considered as operation parameters affecting the performance of the system in removing pollutants and their optimal values were obtained as DO, 0.25-1.7 mg/l, Q WAS , 875-2000 m 3 /day, and Q d /Q e , 10-14%. Using this method, i.e., changing system operation conditions based on influent characteristics, has improved the performance of a system in reducing COD, ammonium, and nitrate in the effluent by 11-41, 17-20 and 15-34, respectively., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Ammonium polyphosphate (APP)-diatomaceous earth (DE) composite prepared by in situ polymerization was modified with silane coupling agent (KH550) and was applied as filler to prepare flame-retardant paper. Fourier transfer infrared, X-ray diffraction and thermogravimetry were used to characterize the structure and properties of the fillers, and limiting oxygen index (LOI), cone calorimeter and field-emission scanning electron microscope were used to investigate the flame-retardant properties of the filled paper. Results showed that chemical bonds occurred between APP-10 % DE filler and KH550, and APP-10 % DE filler had lower water solubility and better crystallization and thermostability after it was modified with KH550. Paper filled with modified APP-10 % DE filler had higher LOI value and lower heat release rate and mass loss at the same filler loading, and its charred residue collected after cone calorimeter test was more compact and strong. Surface modification of APP-10 % DE filler with KH550 improves its flame-retardant effect on paper. [ABSTRACT FROM AUTHOR]

To study the inorganic nitrogen in the process of interaction of river and groundwater and the changes in the microbial community, a vertical simulation device was used to simulate groundwater recharge to river water (upwelling) and river water recharge to groundwater (downwelling). The inorganic nitrogen concentrations in the soil and water solution as well as the characteristics of the microbial community were assessed to determine the inorganic nitrogen transformation and microbial community response in the heterogeneous interaction zone under hydrodynamic action, and the interaction mechanism between nitrogen transformation and the microbial community in the interaction zone was revealed. The removal rates of NO 3 - -N in the simulated solution reached 99.1% and 99.3% under the two fluid-groundwater conversion modes, and the prolonged hydraulic retention time (HRT) of the oxidization-reduction layer in the fine clay area and the high organic matter content made the inorganic nitrogen transformation process dominated by microorganisms more complete. The denitrification during upwelling, dominated by denitrifying bacteria in Sphingomonas, Pseudomonas, Bacillus, and Arthrobacter, was stronger than that during downwelling. Dissimilatory nitrate reduction to ammonium (DNRA), controlled by some aerobic bacteria in Pseudomonas, Bacillus, and Desulfovibrio, was more intense in downflow mode than upflow mode., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The impact of high siltation and accumulation of organic and waste material in the intertidal of the dammed Ba Lai River in Vietnam as part of the Mekong estuarine system was investigated by means of marine free-living nematodes. Nutrients content (nitrate, ammonium, total phosphorus, total nitrogen), total suspended solids, total organic carbon, coliform, bacteria E. coli, pH, dissolved oxygen, total dissolved solids, methane and hydrogen sulfide concentration, and the nematode communities were characterized in sediment at selected stations along the river above and below the dam. Our results found elevated methane concentrations at the upstream side of the dam while hydrogen sulfide concentrations found to be highest in the downstream side of the dam. Furthermore, methane and hydrogen sulfide concentrations were correlated to nematode community characteristics such as trophic composition densities and genera composition. There was a clear difference between the communities above and below the dam. The discontinuous nematode community distribution indicated that the Ba Lai River is impacted by dam construction. Potentially the high deposition and eutrophication could turn the area into a methane-rich area related to predicted impact on nematodes., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The configuration and the effective operation of constructed rapid infiltration (CRI) systems are of significance for advanced wastewater treatment. In this study, a novel CRI system was developed with a compact structure consisting of two stages, i.e., oxic and anoxic stages. The CRI system was continuously operated for about 140 days under different aeration modes, i.e., tidal flow, continuous aeration, and intermittent aeration. Nitrogen removal was not desirable with tidal flow due to the insufficient oxygen supply in the oxic stage for nitrification, while continuous aeration could achieve good performance for chemical oxygen demand (COD), ammonium, total nitrogen (TN), and total phosphorus (TP) removal. By comparison, the CRI system operated with intermittent aeration was more favorable due to the effective removal ability for pollutants and relatively lower energy demand. The microbial community analysis revealed that Proteobacteria was the dominant phylum in both oxic and anoxic stages of the developed CRI system. Functional microbial groups (Plasticicumulans, Pseudomonas, and Nitrospira in the oxic stage; Thauera, Candidatus&#95;Competibacter, and Dechloromonas in the anoxic stage) were identified for the mediation of carbon, nitrogen, and phosphorus in the system. This study evaluated the feasibility and the optimal aeration mode of the developed CRI system for advanced wastewater treatment, which could satisfy the requirement for the high standard of effluent quality., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

High volumetric productivities can be achieved when perfusion processes are operated at high cell densities. Yet it is fairly challenging to keep high cell density cultures in a steady state over an extended period. Aiming for robust processes, cultures were operated at a constant biomass specific perfusion rate (BSPR) in this study. The cell density was monitored with a capacitance probe and a continuous bleed maintained the targeted viable cell volume. Despite our tightly controlled BSPR, a gradual accumulation of ammonium and changes in cell diameter were observed during the production phase for three different monoclonal antibodies. Although a lot of efforts in media optimization have been made to reduce ammonium in fed-batch process, less examples are known about how media components impact the cellular metabolism and thus the quality of monoclonal antibodies in continuous processes. In this study, we show that a continuous Na-pyruvate feed (2 g/L/day) strongly reduced ammonium production and stabilized fucosylation, sialylation and high mannose content for three different mAbs., (© 2022 Wiley Periodicals LLC.)

Denitrifying woodchip bioreactors are a best management practice to reduce nitrate-nitrogen (NO 3 -N) loading to surface waters from agricultural subsurface drainage. Their effectiveness has been proven in many studies, although variable results with respect to performance indicators have been observed. This paper serves the purpose of synthesizing the current state of the science in terms of the microbial community, its impact on the consistency of bioreactor performance, and its role in the production of potential harmful by-products including greenhouse gases, sulfate reduction, and methylmercury. Microbial processes other than denitrification have been observed in these bioreactor systems, including dissimilatory nitrate reduction to ammonia (DNRA) and anaerobic ammonium oxidation (anammox). Specific gene targets for denitrification, DNRA, anammox, and the production of harmful by-products are identified from bioreactor studies and other environmentally relevant systems for application in bioreactor studies. Lastly, cellulose depletion has been observed over time via increasing ligno-cellulose indices, therefore, the microbial metabolism of cellulose is an important function for bioreactor performance and management. Future work should draw from the knowledge of soil and wetland ecology to inform the study of bioreactor microbiomes., (© 2021 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Anaerobic ammonium oxidation (ANAMMOX) has been regarded as an efficient process to treat nitrogen-containing wastewater. However, the treatment process is not fully understood in terms of reaction mechanisms, process simulation, and control. In this paper, a multi-objective control strategy mixed soft-sensing model (MCSSM) is developed to systematically design the operating variations for multi-objective control by integrating the developed model, a least square support vector machine optimized with principal component analysis (PCA-LSSVM) and non-dominated sorting genetic algorithm-II (NSGA-II). The results revealed that the PCA-LSSVM model is a feasible and efficient tool for predicting the effluent ammonia nitrogen concentration ([Formula: see text]) and the total nitrogen removal concentration (C TN, rem ) with determination coefficients (R 2 ) were 0.997 for [Formula: see text] and 0.989 for C TN, rem , and gives us the reasonable solutions in influent by using NSGA-II. To achieve a better removal effect, the influent pH should be kept between 7.50 and 7.52, the COD/TN ratio is suggested to maintain at 0.15 and the NH 4 + -N/NO 2 - -N ratio is suggested to maintain at 0.61. The developed MCSSM approach and its general modeling framework have a high potential of applicability and guidance to bioprocess in wastewater treatment, and numerical models can be structured for predicting and optimization and experiments can be conducted for data acquisition and model establishment.

A straightforward photo-annealing approach was developed for building functional polymer layers on paper. Conducting polyaniline with the ability for photothermal conversion can be readily annealed by near-infrared light. The annealed polymers become both insulating and hydrophobic. Selective photo-annealing produces a functional layer with patterned conductive arrays. This material exhibits real-time response to ammonium gas. Complete photo-annealing preserves the porous structure but changes the wettability of the polyaniline-nanofiber film. [ABSTRACT FROM AUTHOR]

Substrate concentrations greatly influence bacterial growth and metabolism. However, optimal nitrogen concentrations for anammox bacteria in nitrogen-limited environments remain unclear. Here, we observed enhanced nitrogen metabolism and anabolism of anammox bacteria at low nitrogen conditions. Efficient nitrogen removal was achieved at ammonium and nitrite influent concentration of 30 mg/L under HRT of 1 hr, with an average nitrogen removal rate (NRR) of 0.73 kg N/(m 3 ·day) in I-ABR composed of four compartments. The highest anammox activity of 6.25 mmol N/ (gVSS·hr) was observed in the fourth compartment (C4) with the lowest substrate levels (ammonium and nitrite of 11.6 mg/L and 7 mg/L). This could be resulted from the highest expression level of genes involved in nitrogen metabolism in C4, which was 1.49-1.67 times higher than that in other compartments. Besides, the second compartment (C2) exhibited the most active anabolism at ammonium and nitrite of 17 mg/L and 13 mg/L, respectively, which contributed to the most active amino acid synthesis and thus the highest EPS (1.35 times higher) in C2. This enhanced amino acid auxotrophy between anammox bacteria with heterotrophs, and consequently, heterotrophs thrived and competed for nitrite. These results hint at the potential application of anammox process in micro-polluted water. PRACTITIONER POINTS: High nitrogen removal and efficient biomass retention at low nitrogen concentrations under short HRT was achieved in I-ABR. Optimal concentrations for anammox nitrogen removal and anabolism were discussed under low nitrogen concentrations. More active anabolism contributed to enhanced amino acid synthesis and thus higher EPS contents. Low substrate levels led to enhanced expression of genes involved in nitrogen metabolism and thus high anammox activity., (© 2021 Water Environment Federation.)

Abstract: The effects of the addition of ammonium magnesium phosphate (AMP) to the paper of an electrically heated cigarette (EHC) prototype on smoke composition and toxicity were quantified and the underlying mechanisms investigated. Smoke from EHC prototypes with and without AMP and from conventional cigarettes, i.e. the University of Kentucky Standard Reference Cigarette 1R4F and eight American-blend market cigarettes, was compared. Endpoints for comparison were smoke chemistry, where toxic constituents were measured, cytotoxic activity, as measured in murine fibroblasts embryo cells by the Neutral Red Uptake Assay, and genotoxic activity, as measured in bacteria by the Salmonella Reverse Mutation Assay and in murine lymphoma cells by the TK Assay. The addition of AMP to the EHC led to a reduction of toxic substances and toxicological activity of approximately 30% compared to the EHC without AMP. Compared to the conventional cigarettes, the EHC with AMP showed reductions of 75–90%. Smoke from the EHCs generated in nitrogen atmospheres supplemented with different concentrations of ammonia and oxygen was assayed for its in vitro cytotoxicity and genotoxicity. The results indicate that the ammonia released by AMP at the heating site of the EHC is responsible for the reductions in cytotoxicity and mutagenicity for the EHC with AMP compared with the EHC without AMP. Thus, while the EHC approach distinctly reduces toxic smoke constituents compared to conventional cigarettes, the use of AMP in the paper of an EHC leads to further distinct reductions. In the study presented here, in vitro assays were used as quantitative tools to investigate toxicity-related mechanisms. [Copyright &y& Elsevier]

Background: The so-called 'Neapolitan limmo' or 'lemoncetta Locrese' is an old and now rare Mediterranean sweet lime, similar to lemon but smaller. It is a fruit distinguished from orange, lemon, mandarin, and lime for its sweeter, watery, and non-acidic taste, with a pH between 5.6 and 5.9. No compositional studies are currently available for this citrus fruit. Here we report, for the first time, the distribution in the limmo juice of free amino acids and their main derivatives such as betaines and related ammonium compounds., Results: Seven proteinogenic amino acids (proline, asparagine, serine, aspartic acid, glutamine, alanine, and threonine) and a non-protein amino acid (γ-aminobutyric acid) characterize Neapolitan limmo juice. Proline betaine is the predominant betaine. The data were compared with those of other important citrus juices., Conclusion: The specific 'taste quality' of Neapolitan limmo juice can be attributed to its peculiar composition in amino acids. The species-specific presence of the ammonium compound derivatives of the amino acid proline, with proline betaine as the predominant betaine, characterize the non-acidic varieties of Mediterranean sweet lime. Our study constitutes an important step towards the repopulation of this ancient plant and its exploitation in food industry. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)

Anaerobic ammonium oxidation (anammox) is a novel process of deammonification that exhibits superior ecological and economic potential compared to that of traditional heterotrophic processes. Although this process has been successfully implemented in treating high-strength nitrogen-contaminated wastewater, it still faces many challenges in treating mainstream municipal wastewater. This review aims to provide an overview of the status and challenges of mainstream anammox-based processes. The different configurations and crucial factors are discussed in this review. Finally, the future needs for feasible application are stated. PRACTITIONER POINTS: Factors restricting mainstream application of anammox-based processes are reviewed. Control strategies for selecting and maintaining anammox bacteria are discussed. Recent advances in nitrite production via partial nitrification or denitrification are summarized. Future needs for the feasible application of anammox-based nitrogen removal technology for mainstream municipal wastewater treatment are outlined., (© 2020 Water Environment Federation.)

Aims: The use of plant growth-promoting micro-organisms (PGPMs) to improve plant-nutrient acquisition has a long history but reproducibility remains a challenge. Recent findings suggest an important role of suitable inoculant-fertilizer combinations for the expression of PGPM-effects, particularly with respect to nitrogen (N) supply. In face of the well-documented N form effects on rhizosphere pH, this study addressed the impact of ammonium-assisted PGPM-interactions on the acquisition of sparingly soluble calcium-phosphates as affected by soil pH., Methods and Results: The effects of stabilized ammonium fertilization combined with the PGPM inoculant Bacillus amyloliquefaciens FZB42 on the acquisition of rock phosphate in maize were examined on two soils (moderately acidic-pH 5·6 and alkaline-pH 7·8). On the two contrasting soils, FZB42 improved the P status and promoted plant growth by different mechanisms. On the acidic soil, a combination of ammonium-fertilization with FZB42 increased P-acquisition by Rock P solubilization via rhizosphere acidification but P-supply in the noninoculated control was already sufficient to meet the plant demands. By contrast, on the alkaline soil, plant growth-promotion was associated with FZB42-induced root growth stimulation., Conclusion: The results suggest a significant impact of soil pH on performance and the mode of action of PGPM inoculants, to be considered for practical applications., Significance and Impact of the Study: The study advanced existing knowledge on PGPM-assisted P solubilization as affected by different soil properties. The results suggest perspectives for management options to be considered for efficient use of PGPMs in terms of selecting application strategies with compatible PGPM-fertilizer combinations, depending on soil pH conditions., (© 2020 The Authors. Journal of Applied Microbiology published by John Wiley & Sons Ltd on behalf of Society for Applied Microbiology.)

Cytokinins are growth-regulating plant hormones that are considered to adjust plant development under environmental stresses. During sole ammonium nutrition, a condition known to induce growth retardation of plants, altered cytokinin content can contribute to the characteristic ammonium toxicity syndrome. To understand the metabolic changes in cytokinin pools, cytokinin biosynthesis and degradation were analyzed in the leaves and roots of mature Arabidopsis plants. We found that in leaves of ammonium-grown plants, despite induction of biosynthesis on the expression level, there was no active cytokinin build-up because they were effectively routed toward their downstream catabolites. In roots, cytokinin conjugation was also induced, together with low expression of major synthetic enzymes, resulting in a decreased content of the trans-zeatin form under ammonium conditions. Based on these results, we hypothesized that in leaves and roots, cytokinin turnover is the major regulator of the cytokinin pool and does not allow active cytokinins to accumulate. A potent negative-regulator of root development is trans-zeatin, therefore its low level in mature root tissues of ammonium-grown plants may be responsible for occurrence of a wide root system. Additionally, specific cytokinin enhancement in apical root tips may evoke a short root phenotype in plants under ammonium conditions. The ability to flexibly regulate cytokinin metabolism and distribution in root and shoot tissues can contribute to adjusting plant development in response to ammonium stress., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Kacper Dziewit reports financial support was provided by University of Warsaw. Anna Podgorska reports a relationship with University of Warsaw that includes: employment. Bozena Szal reports a relationship with University of Warsaw that includes: employment. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Masson SAS.)

Microbial electrolysis cells (MEC) have been identified as an energy efficient system for ammonium recovery from wastewater. However, high ammonium concentrations at the anode can have inhibitory effects. This work aims to determine the effects on current generation performance and active ammonia nitrogen recovery in wastewater containing 0.5 to 2.5 g N-NH 4 + /L. The study also evaluates the effect of two cathode materials, stainless steel (SS-MEC) and nickel foam (NF-MEC). When the concentration of ammonium in the feed was increased from 0.5 to 1.5 g N-NH 4 + /L the maximum current density increased from 3.2 to 3.9 A/m 2 , but a further increase to 2.5 g N-NH 4 + /L inhibited the biofilm activity, decreasing the current density to 0.5 A/m 2 . The maximum ammonium removal and recovery efficiencies were 71 % and 33 % at 0.5 g N-NH 4 + /L. The SS-MEC exhibited more energy efficient ammonium recovery compared to the NF-MEC, requiring 3.6 kWh/kg N,recovered at 0.5 gN-NH 4 +/L. The highest ammonium recovery rate of 33 g N /m 2 /d (1.5 gN-NH 4 + /L) was obtained with an energy consumption of 4.5 kWh/kg N,recovered . Conversely, a lower recovery rate (10 g N /m 2 /d for 2.5 gN-NH 4 + /L) resulted in reduced energy consumption at 2.1 kWh/kg N,recovered . This highlights the inherent trade-off between energy consumption and efficient ammonium recovery in the process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

The DEnitrifying AMmonium OXidation (DEAMOX) has been proven to be a promising process treating contaminated surface water containing ammonia and nitrate, while the enrichment of the slow-growing anammox bacteria (AnAOB) remains a challenge. In this study, a novel polyurethane-adhesion vermiculite/tourmaline (VTP) modified carrier was developed to achieve effective enrichment of AnAOB. The results demonstrated that the VTP-1 (vermiculite: tourmaline = 1:1) system exhibited the greatest performance with the total nitrogen removal efficiency reaching 87.6% and anammox contributing 63% to nitrogen removal. Scanning electron microscope analysis revealed the superior biofilm structure of the VTP-1 carrier, providing attachment for AnAOB. The addition of VTP-1 promoted the secretion of EPS (extracellular polymeric substances) by microorganisms, which increased to 85.34 mg/g VSS, contributing to the aggregation of anammox cells. The favorable substrate microenvironment created by NH 4 + adsorption and NO 2 - supply via partial denitrification process facilitated the growth of AnAOB. The relative abundance of Candidatus Brocadia and Thauera increased from 0.04% to 0.3%-1.03% and 2.06% in the VTP-1 system, respectively. This study sheds new light on the anammox biofilm formation and provides a valid approach to initiate the DEAMOX process for low nitrogen polluted water treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The ammonium exceedance discharge from sewage treatment plants has a great risk to the stable operation of subsequent constructed wetlands (CWs). The effects of high ammonium shocks on submerged macrophytes and epiphytic biofilms on the leaves of submerged macrophytes in CWs were rarely mentioned in previous studies. In this paper, the 16S rRNA sequencing method was used to investigate the variation of the microbial communities in biofilms on the leaves of Vallisneria natans plants while the growth characteristics of V. natans plants were measured at different initial ammonium concentrations. The results demonstrated that the total chlorophyll and soluble sugar synthesis of V. natans plants decreased by 51.45% and 57.16%, respectively, and malondialdehyde content increased threefold after 8 days if the initial NH 4 + -N concentration was more than 5 mg/L. Algal density, bacterial quantity, dissolved oxygen, and pH increased with high ammonium shocks. The average removal efficiencies of total nitrogen and NH 4 + -N reached 73.26% and 83.94%, respectively. The heat map and relative abundance analysis represented that the relative abundances of phyla Proteobacteria, Cyanobacteria, and Bacteroidetes increased. The numbers of autotrophic nitrifiers and heterotrophic nitrification aerobic denitrification (HNAD) bacteria expanded in biofilms. In particular, HNAD bacteria of Flavobacterium, Hydrogenophaga, Acidovorax, Acinetobacter, Pseudomonas, Aeromonas, and Azospira had higher abundances than autotrophic nitrifiers because there were organic matters secreted from declining leaves of V. natans plants. The analysis of the nitrogen metabolic pathway showed aerobic denitrification was the main nitrogen removal pathway. Thus, the nitrification and denitrification bacterial communities increased in epiphytic biofilms on submerged macrophytes in constructed wetlands while submerged macrophytes declined under ammonium shock loading., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)