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Concerns over toxic nitrogenous disinfection byproducts (N-DBPs) necessitate identifying their precursors in source water. Natural organic amino compounds are known precursors to N-DBPs. Three Suwannee River (SR) standard reference materials (SRMs), humic acids (HA), fulvic acids (FA), and natural organic matter (NOM), are commonly used to study DBP formation, but the chemical makeup of amino compounds in SRSRMs remains largely unknown. To address this, we combined stable hydrogen/deuterium isotope labeling, HDPairFinder bioinformatics, and nontargeted high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS) to characterize these compounds in SRSRMs. This method classifies reactive amines, provides accurate masses and MS/MS spectra, and quantifies intensities. We identified 2707 high-quality features with primary and/or secondary amines in SRSRMs and 75% of them having an m / z < 300. Across all three SRSRMs, 327 amino features were detected, while 856, 794, and 200 unique features were found in SRNOM, SRHA, and SRFA, respectively. In North Saskatchewan River (NSR) samples, a total of 6449 amino features were detected, 818 of them matched those in SRSRMs, and 87% of them were different between the two rivers. Using chemical standards, we confirmed 10 compounds and tentatively identified 5 more. This study highlights similarities and differences in reactive N-precursors in SRSRMs and local river water, enhancing the understanding of geo-differences in reactive N-precursors in different source waters.

Herein, we reported the dual functions of molybdenum disulfide/sulfur-doped graphitic carbon nitride (MoS 2 /SGCN) composite as a sensing material for electrochemical detection of 4-NP and a catalyst for 4-NP degradation. The MoS 2 nanosheet, sulfur-doped graphitic carbon nitride (SGCN) and MoS 2 /SGCN were characterized using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) spectroscopy and X-ray photoelectron spectroscopy (XPS). Electrochemical characterization of these materials with electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) in 1 mM K 4 [Fe(CN) 6 ] 3-/4- show that the composite has the lowest charge transfer resistance and the best electrocatalytic activity. The limit of detection (LOD) and the linear range of 4-nitrophenol at MoS 2 /SGCN modified glassy carbon electrode (MoS 2 /SGCN/GCE) were computed as 12.8 nM and 0.1 - 2.6 μM, respectively. Also, the percentage recoveries of 4-NP in spiked tap water samples ranged from 97.8 - 99.1 %. The electroanalysis of 4-NP in the presence of notable interferons shows that the proposed electrochemical sensor features outstanding selectivity toward 4-NP. Additionally, the results of the catalytic degradation of 4-NP at MoS 2 /SGCN show that the nanocatalyst catalyzed the transformation of 4-NP to 4-aminophenol (4-AP) with a first-order rate constant (k) estimated to be 4.2 ×10 -2 s -1 . The results of this study confirm that the MoS 2 /SGCN nanocatalyst is a useful implement for electroanalytical monitoring and catalytic degradation of the hazardous 4-NP in water samples., 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 Authors. Published by Elsevier Inc. All rights reserved.)

Graphitic carbon nitride mutated with metal nanoparticles has captivated great interest as an effective fluorescent sensor for the detection of harmful ions present in water. In the present work, bulk-gCN was synthesized using melamine as precursor, and further Au-gCN nanocomposite were fabricated via in-situ direct reduction deposition method. The structural, morphological, compositional, stability and optical properties of bulk gCN and Au-gCN nanocomposite were examined using various scattering and spectroscopic techniques such as HRTEM, XPS, XRD and SEM. The synthesized bulk gCN straggles during selectivity studies with different cations and anions because of its uneven surface morphology, however in Au-gCN gold nanoparticles are uniformly distributed on the gCN sheets which results in its enhanced selectivity over bulk gCN. This leads to the fabrication of an optical sensor for Fe 3+ and Cr 2 O 7 2- ions with limit of detection of 4.62 and 2.77 μM, respectively. The sensing of Fe 3+ ions corresponds to the photoinduced electron transfer (PET) mechanism, while the detection of chromate species is associated with an inner filter effect (IFE). The practical applicability of the sensor was also evaluated for different environmental water samples. The high stability, sensitivity, and specificity of Au-gCN nanocomposite make it a potential fluorescent probe for Fe 3+ and Cr 2 O 7 2- ions in water samples., 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. Published by Elsevier Ltd.)

The contamination of water sources by pharmaceutical compounds presents global environmental and health risks, necessitating the development of efficient water treatment technologies. In this study, the synthesis, characterization, and evaluation of a novel graphitic carbon nitride-calcined (Fe-Ca) layered double hydroxide (gC 3 N 4 -CLDH) composite for electrochemical degradation of sulfamethoxazole (SMX) in water yielded significant outcomes are reported. SEM, XRD, FTIR, and XPS analyses confirmed well-defined composite structures with unique morphology and crystalline properties. Electrochemical degradation experiments demonstrated >98% SMX removal and >75% TOC removal under optimized conditions, highlighting its effectiveness. The composite exhibited excellent mineralization efficiency across various pH levels, with superoxide radicals (O 2 ●- ) and hydroxyl radicals ( ● OH) identified as primary reactive oxygen species. With remarkable regeneration capability for up to 7 cycles, the gC 3 N 4 -CLDH composite emerges as a highly promising solution for sustainable water treatment. Humic acid (HA) in water significantly slows SMX degradation, suggests complicating SMX degradation with natural organic matter. Despite this, the gC 3 N 4 -CLDH composite effectively degrades SMX in groundwater and industrial wastewater, with slight efficiency reduction in the latter due to higher impurity levels. These findings highlight the complexities of treating pharmaceutical pollutants in various water types. Overall, gC 3 N 4 -CLDH's high removal efficiency, broad pH applicability, sustainability, and mechanistic insights provide a solid foundation for future research and real-world environmental applications., 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.)

Objective: The main objective of this study was to comprehensively investigate the association between trichloramine (TCA) exposure and respiratory health effects in swimming pool workers., Methodology: In this study, air sampling was performed for TCA concentrations at fixed locations (static measurements) and on individual workers (personal measurements) in six indoor public swimming pools during periods of high swimmer attendance over the winter school break. Health effects were evaluated using questionnaires and fractional exhaled nitric oxide (FENO) tests performed before and after the working day., Results: In these swimming pools, the environmental TCA concentration ranged from 0.11 to 0.88 mg/m³. Worker exposure ranged from 0.05 to 0.72 mg/m³ for personal measurements. Furthermore, in each swimming pool, the average worker exposure to TCA exceeded the recommended occupational exposure limit of 0.35 mg/m³. Personal TCA measurements were consistently lower than static measurements performed around the pool, with a reduction ranging from 21% to 49%. This can be explained by the time that the workers spend in the pool area, office, and break room. The most common respiratory health effects self-reported by the workers were coughing, shortness of breath, and sneezing with prevalence rates of 38%, 37%, and 35%, respectively. This study demonstrated an association between TCA exposure and eye irritation. Analysis of the FENO tests revealed that individuals with preexisting asthma or allergies exhibited sustained FENO elevation., Conclusion: The findings suggest that occupational exposure to TCA in indoor swimming pools is a matter of concern. Implementing and improving workplace safety measures is crucial for safeguarding the respiratory health of swimming pool workers., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Occupational Hygiene Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Extensive utilization of pesticides and herbicides to boost agricultural production increased the environmental health risks, which can be mitigate with the aid of highly sensitive detection systems. In this study, an electrochemical sensor for monitoring the carcinogenic pesticides in the environmental samples has been developed based on sulfur-doped graphitic-carbon nitride-gold nanoparticles (SCN-AuNPs) nanohybrid. Thermal polycondensation of melamine with thiourea followed by solvent exfoliation via ultrasonication leads to SCN formation and electroless deposition of AuNPs on SCN leads to SCN-AuNPs nanohybrid synthesis. The chemical composition, S-doping, and the morphology of the nanohybrid were confirmed by various microscopic and spectroscopic tools. The as-synthesized nanohybrid was fabricated with glassy carbon (GC) electrode for determining the carcinogenic hydrazine (HZ) and atrazine (ATZ) in field water samples. The present sensor exhibited superior electrocatalytic activity than GC/SCN and GC/AuNPs electrodes due to the synergism between SCN and AuNPs and the amperometric studies showed the good linear range of detection of 20 nM-0.5 mM and 500 nM-0.5 mM with the limit of detection of 0.22 and 69 nM (S/N = 3) and excellent sensitivity of 1173.5 and 13.96 μA mM -1 cm -2 towards HZ and ATZ, respectively. Ultimately, the present sensor is exploited in environmental samples for monitoring HZ and ATZ and the obtained results are validated with high-performance liquid chromatography (HPLC) technique. The excellent recovery percentage and close agreement with the results of HPLC analysis proved the practicability of the present sensor. In addition, the as-prepared materials were utilized for the photocatalytic degradation of ATZ and the SCN-AuNPs nanohybrid exhibited higher photocatalytic activity with the removal efficiency of 93.6% at 90 min. Finally, the degradation mechanism was investigated and discussed., 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 Authors. Published by Elsevier Inc. All rights reserved.)

Exposure to airborne disinfection by-products, especially trichloramine (TCA), could cause various occupational health effects in indoor swimming pools. However, TCA concentration measurements involve specialized analysis conducted in specific laboratories, which can result in significant costs and time constraints. As an alternative, modeling techniques for estimating exposures are promising in addressing these challenges. This study aims to predict airborne TCA concentrations in indoor swimming pools using a mathematical model, the well-mixed box model, found in the IHMOD tool, freely available on the American Industrial Hygiene Association website. The model's predictions are compared with TCA concentrations measured during various bather load scenarios. The research involved conducting 2-hr successive workplace measurements over 16- to 18-hr periods in four indoor swimming pools in Quebec, Canada. TCA concentrations were estimated using the well-mixed box model, assuming a homogeneous mixing of air within the swimming pool environment. A novel approach was developed to estimate the TCA generation rate from swimming pool water, incorporating the number of swimmers in the model. Average measured concentrations of TCA were 0.24, 0.26, 0.14, and 0.34 mg/m 3 for swimming pools 1, 2, 3, and 4, respectively. The ratio of these measured average concentrations to their corresponding predicted values ranged from 0.51 to 1.30, 0.67 to 1.04, 0.57 to 1.14, and 0.68 to 1.49 for the respective swimming pools. In a worst-case scenario simulating the swimming pool at full capacity (maximum bathers allowed), TCA concentrations were estimated as 0.23, 0.36, 0.14, and 0.37 mg/m 3 for swimming pools 1, 2, 3, and 4. Recalculated concentrations by adjusting the number of swimmers so as not to exceed the recommended occupational limit concentration of 0.35 mg/m 3 gives a maximum number of swimmers of 63 and 335 instead of currently 80 and 424 for swimming pools 2 and 4, respectively. Similarly, for swimming pools 1 and 3, the maximum number of swimmers could be 173 and 398 (instead of the current 160 and 225, respectively). These results demonstrated that the model could be used to estimate and anticipate airborne TCA levels in indoor swimming pools across various scenarios.

Eight nitrogenous compounds including five undescribed ones, aeswilnitrousol A (1), aeswilnitrousosides BD (2-4), and 6-(2-hydroxy-3-methylbutylamino)-8-oxoadenine (5) were isolated from the seeds of Aesculus wilsonii. Their structures and absolute configurations were established based on spectroscopic determination, calculated electronic circular dichroism (ECD) analysis, as well as chemical reaction methods. Among the three known compounds, 7 and 8 were obtained from the Aesculus genus for the first time, and 6 was gained from this plant initially. The 13 C NMR data of 7 and 8 were reported for the first time. Moreover, the inhibitory effect of all the isolates against LPS-induced nitric oxide production in RAW264.7 macrophages was evaluated. As a result, compounds 2 and 8 exhibited anti-inflammatory activity in a concentration-dependent manner at 10, 25, and 50 μM., 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 Elsevier B.V. All rights reserved.)

The uncontrolled release of antibiotics into the environment would be extremely harmful to human health and ecosystems. Therefore, it is in urgent need to monitor the environment and promote the detection and degradation of antibiotics to the relatively harmless by-products to a feasible extent. Graphitic carbon nitride (g-C 3 N 4 ) is a non-metallic n-type semiconductor that can be used for the antibiotic detection and degradation due to its easy synthesis process, excellent chemical stability and unique optical properties. Unfortunately, the utilization of visible light, electron-hole recombination and electron conductivity have hindered its potential applications in the fields of photocatalytic degradation and electrochemical detection. Although previous publications have highlighted the diverse modification methods for the g-C 3 N 4 -based materials, the underlying structure-performance relationships of g-C 3 N 4 , especially for the detection and degradation of antibiotics, remains to be further explored. In view of this, the current review centered on the recent progress in the modification techniques of g-C 3 N 4 , the detection and degradation of antibiotics using the g-C 3 N 4 -based materials, as well as the potential antibiotic degradation mechanisms of the g-C 3 N 4 -based materials. Additionally, the underlying applications of the g-C 3 N 4 -based materials for antibiotic detection and degradation were also prospected. This review would provide a valuable research foundation and the up-to-date information for the g-C 3 N 4 -based materials to combat antibiotic pollution in the environment., 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. Published by Elsevier B.V.)

Nitrogen-containing organic compounds (NOCs), a type of important reactive-nitrogen species, are abundant in organic aerosols in haze events observed in Northern China. However, due to the complex nature of NOCs, the sources, formation, and influencing factors are still ambiguous. Here, the molecular composition of organic matters (OMs) in hourly PM 2.5 samples collected during a haze event in Northern China was characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). We found that CHON compounds (formulas containing C, H, O, and N atoms) dominated the OM fractions during the haze and showed high chemodiversity and transformability. Relying on the newly developed revised-workflow and oxidation-hydrolyzation knowledge for CHON compounds, 64% of the major aromatic CHON compounds (>80%) could be derived from the oxidization or hydrolyzation processes. Results from FT-ICR MS data analysis further showed that the aerosol liquid water (ALW)-involved aqueous-phase reactions are important for the molecular distribution of aromatic-CHON compounds besides the coal combustion, and the ALW-involved aromatic-CHON compound formation during daytime and nighttime was different. Our results improve the understanding of molecular composition, sources, and potential formation of CHON compounds, which can help to advance the understanding for the formation, evolution, and control of haze.

The NPN compounds from dairy processing side-streams are a promising source for new products. In this study, the NPN profile of lactose production samples was screened using GC-MS and 1 H NMR spectroscopy. These analytical platforms allowed the identification of 35 NPN compounds including, amino acids and derivatives, amino alcohols, organic acids, and other classes. Quantification of the NPN compounds revealed their attenuation by unit operations during a trial lactose production. Urea, ammonia, glycerophosphocholine, creatine, creatinine, orotic acid and choline were the most dominant compounds. Mother liquor concentrate had the highest concentration of NPN, whereas lactose powder had substantial relative amounts of N-acetylglucosamine, phosphocholine and orotic acid. The NPN compounds added up to 57-99% of the total nitrogen, depending on the sample type. The highest nitrogen recovery was found for the reverse osmosis retentate, mother liquid concentrate, wash water and reverse osmosis permeate, whereas the lowest was found for lactose powder., 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 © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Rhizodeposition is the export of organic compounds from plant roots to the soil. Carbon allocation towards rhizodeposition has to be balanced with allocation for other physiological functions, which depend on both newly assimilated and stored nonstructural carbohydrate (NSC). To test whether the exudation of primary metabolites scales with plant NSC status, we studied diurnal dynamics of NSC and amino acid (AA) pools and fluxes within the plant and the rhizosphere. These diurnal dynamics were measured in the field and under hydroponic-controlled conditions. Further, C-limiting treatments offered further insight into the regulation of rhizodeposition. The exudation of primary metabolites fluctuated diurnally. The diurnal dynamics of soluble sugars (SS) and AA concentrations in tissues coincided with exudate pool fluctuations in the rhizosphere. SS and AA pools in the rhizosphere increased with NSC and AA pools in the roots. C starvation treatments offset the balance of exudates: AA exudate content in the rhizosphere significantly decreased while SS exudate content remained stable. Our results suggest that rhizodeposition is to some extent controlled by plant C:N status. We propose that SS exudation is less controlled than AA exudation because N assimilation depends on controlled C supply while SS exudation relies to a greater extent on passive diffusion mechanisms., (© 2022 John Wiley & Sons Ltd.)

The mining of ionic rare earth elements in Ganzhou left large area of barren tailings with severe vegetation destruction in pressing needs of remediation. However, the remediating effects of soil additives combined with revegetation on the preservation of nutrients in the tailings and microbial communities were rarely studied. For this purpose, pilot experiments were implemented in a field, with the control group (CK) only cultivating plants without adding materials, and three treatments including peanut straw biochar composite (T1), phosphorus‑magnesium composite (T2) and modified zeolite composite (T3) along with the cultivation of Medicago sativa L., Paspalum vaginatum Sw. and Lolium perenne L. Soil pH and organic matter in CK significantly decreased from 4.90 to 4.17 and from 6.62 g/kg to 3.87 g/kg after six months, respectively (p ≤ 0.05), while all the treatments could effectively buffer soil acidification (over 5.74) and delay the loss of soil organic matter. Soil cation exchange capacity was still below the detection limit in all the groups except T2. The results of rainfall runoff monitoring indicated that compared with CK, only T2 could significantly reduce the runoff loss of soil NO 3 - and SO 4 2- by 45.61 %-75.78 % and 64.03 %-76.12 %, respectively (p ≤ 0.05). Compared with CK, the bacterial diversity in T2 and T3 significantly increased 21.18 % and 28.15 %, respectively (p ≤ 0.05), while T1 didn't change the bacterial or fungal diversity (p > 0.05). Co-occurrence network analysis showed that compared with CK, the whole microbial communities interacted more closely in the three treatments. Functional prediction of the microbial communities revealed all the treatments were dominated by carbon transforming bacteria and saprotrophic fungi except T2. This study demonstrated that the composite materials combined with revegetation couldn't retain soil nitrogen compounds and sulfate in rare earth tailings in the long term., 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 © 2022 Elsevier B.V. All rights reserved.)

Donkeys are indispensable livestock in China because they have transport function and medicinal value. With the popularization of artificial insemination on donkeys, semen cryopreservation technology has gradually become a research hotspot. Seminal plasma is a necessary medium for transporting sperm and provides energy and nutrition for sperm. Seminal plasma metabolites play an important role in the process of sperm freezing, and also have an important impact on sperm motility and fertilization rate after freezing and thawing. In this study, liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was used to compare the metabolic characteristics of seminal plasma of high freezability (HF) and low freezability (LF) male donkeys. We identified 672 metabolites from donkey seminal plasma, of which 33 metabolites were significantly different between the two groups. Metabolites were identified and categorized according to their major chemical classes, including homogeneous non-metal compounds, nucleosides, nucleotides, and analogues, organosulphur compounds, phenylpropanoids and polyketide, organoheterocyclic compounds, organic oxygen compounds, benzenoids, organic acids and derivatives, lipids and lipid-like molecules, organooxygen compounds, alkaloids and derivatives, organic nitrogen compounds. The results showed that the contents of phosphatidylcholine, piceatannol and enkephalin in donkey semen of HF group were significantly higher than those of LF group (p < .05), while the contents of taurocholic and lysophosphatidic acid were significantly lower than those of LF group (p < .05). The different metabolites were mainly related to sperm biological pathway response and oxidative stress. These metabolites may be considered as candidate biomarkers for different fertility in jacks., (© 2022 Wiley-VCH GmbH.)

Background: There is scarce information focused on the effect of weather conditions and air pollution on specific acute viral respiratory infections, such as rhinovirus (RV), with a wide clinical spectrum of severity., Objective: The aim of this study was to analyze the association between episodes of severe respiratory tract infection by RV and air pollutant concentrations (NO x and SO 2 ) in the reference area of a pediatric university hospital., Methods: An analysis of temporal series of daily values of NO x and SO 2 , weather variables, circulating pollen and mold spores, and daily number of admissions in the pediatric intensive care unit (PICU) with severe respiratory RV infection (RVi) in children between 6 months and 18 years was performed. Lagged variables for 0-5 days were considered. The study spanned from 2010 to 2018. Patients with comorbidities were excluded., Results: One hundred and fifty patients were admitted to the PICU. Median age was 19 months old (interquartile range [IQR]: 11-47). No relationship between RV-PICU admissions and temperature, relative humidity, cumulative rainfall, or wind speed was found. Several logistic regression models with one pollutant and two pollutants were constructed but the best model was that which included average daily NO x concentrations. Average daily NO x concentrations were related with the presence of PICU admissions 3 days later (odds ratio per IQR-unit increase: 1.64, 95% confidence interval: 1.20-2.25))., Conclusions: This study has shown a positive correlation between NO x concentrations at Lag 3 and children's PICU admissions with severe RV respiratory infection. Air pollutant data should be taken into consideration when we try to understand the severity of RVis., (© 2022 The Authors. Pediatric Pulmonology published by Wiley Periodicals LLC.)

Field sample preparation is important and interesting for analysis of nitrogen and sulfur containing aromatic compounds (N,S-CACs) in environmental aqueous samples. In this connection, a new functional groups-rich adsorbent based on porous monolith (ABM) was fabricated by in-situ copolymerization of allylaminocarbonylphenyl boronic acid/styrene and ethylene glycol dimethacrylate. The prepared ABM was employed as the extraction medium of homemade portable multichannel in-tip microextraction device (PMMD) for on-site entrapment of N,S-CACs in various waters. Because of the abundant functional groups, the obtained ABM/PMMD exhibited satisfactory capture capability towards studied N,S-CACs, and the enrichment factors varied from 454 to 491. Under the optimized fabrication conditions, adsorption and desorption parameters, the developed ABM/PMMD was used to field capture investigated N,S-CACs and followed by quantification with high performance liquid chromatography. The limits of detection were in the ranges of 0.00030-0.0016 µg/L. Recoveries with low, medium and high spiked contents located in the range of 82.1-118% with good repeatability (RSDs<9%). In addition, traditional laboratory sample pretreatment approach was employed to verify the reliability of the established method. Results well evidenced that the practicability of introduced ABM/PMMD in the field sample preparation of N,S-CACs in environmental waters., 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 © 2022 Elsevier B.V. All rights reserved.)

N-containing organic compounds (NOCs) in humic-like substances (HULIS) emitted from biomass burning (BB) and coal combustion (CC) were characterized by ultrahigh-resolution mass spectrometry in the positive electrospray ionization mode. Our results indicate that NOCs include CHON+ and CHN+ groups, which are detected as a substantial fraction in both BB- and CC-derived HULIS, and suggest that not only BB but also CC is the potential important source of NOCs in the atmosphere. The CHON+ compounds mainly consist of reduced nitrogen compounds with other oxygenated functional groups, and straw- and coal-smoke HULIS exhibit a lower degree of oxidation than pine-smoke HULIS. In addition, the NOCs with higher N atoms (N 2 and/or N 3 ) generally bear higher modified aromaticity index (AI mod ) values and are mainly contained in BB HULIS, especially in straw-smoke HULIS, whereas the NOCs with a lower N atom (N 1 ) always have relatively lower AI mod values and are the dominant NOCs in CC HULIS. These findings imply that the primary emission from CC may be a significant source of N 1 compounds, whereas high N number (e.g., N 2-3 ) compounds could be associated with burning of biomass materials. Further study is warranted to distinguish the NOCs from more sources.

The understanding of deep chlorophyll layers (DCLs) in the Great Lakes-largely reported as a mix of picoplankton and mixotrophic nanoflagellates-is predominantly based on studies of deep (>30 m), offshore locations. Here, we document and characterize nearshore DCLs from two meso-oligotrophic embayments, Twelve Mile Bay (TMB) and South Bay (SB), along eastern Georgian Bay, Lake Huron (Ontario, Canada) in 2014, 2015, and 2018. Both embayments showed the annual formation of DCLs, present as dense, thin, metalimnetic plates dominated by the large, potentially toxic, and bloom-forming cyanobacteria Planktothrix cf. isothrix . The contribution of P. cf. isothrix to the deep-living total biomass (TB) increased as thermal stratification progressed over the ice-free season, reaching 40% in TMB (0.6 mg/L at 9.5 m) and 65% in South Bay (3.5 mg/L at 7.5 m) in 2015. The euphotic zone in each embayment extended down past the mixed layer, into the nutrient-enriched hypoxic hypolimnia, consistent with other studies of similar systems with DCLs. The co-occurrence of the metal-oxidizing bacteria Leptothrix spp. and bactivorous flagellates within the metalimnetic DCLs suggests that the microbial loop plays an important role in recycling nutrients within these layers, particularly phosphate (PO 4 ) and iron (Fe). Samples taken through the water column in both embayments showed measurable concentrations of the cyanobacterial toxins microcystins (max. 0.4 µg/L) and the other bioactive metabolites anabaenopeptins (max. ~7 µg/L) and cyanopeptolins (max. 1 ng/L), along with the corresponding genes (max. in 2018). These oligopeptides are known to act as metabolic inhibitors (e.g., in chemical defence against grazers, parasites) and allow a competitive advantage. In TMB, the 2018 peaks in these oligopeptides and genes coincided with the P. cf. isothrix DCLs, suggesting this species as the main source. Our data indicate that intersecting physicochemical gradients of light and nutrient-enriched hypoxic hypolimnia are key factors in supporting DCLs in TMB and SB. Microbial activity and allelopathy may also influence DCL community structure and function, and require further investigation, particularly related to the dominance of potentially toxigenic species such as P. cf. isothrix .

The species Pseudogymnoascus is known as a psychrophilic pathogenic fungus which is ubiquitously distributed in Antarctica. While the studies of its secondary metabolites are infrequent. Systematic research of the metabolites of the Antarctic fungus Pseudogymnoascus sp. HSX2#-11 led to the isolation of one new pyridine derivative, 4-(2-methoxycarbonyl-ethyl)-pyridine-2-carboxylic acid methyl ester ( 1 ), together with one pyrimidine, thymine ( 2 ), and eight diketopiperazines, cyclo -(dehydroAla-l-Val) ( 3 ), cyclo -(dehydroAla-l-Ile) ( 4 ), cyclo -(dehydroAla-l-Leu) ( 5 ), cyclo -(dehydroAla-l-Phe) ( 6 ), cyclo -(l-Val-l-Phe) ( 7 ), cyclo -(l-Leu-l-Phe) ( 8 ), cyclo -(l-Trp-l-Ile) ( 9 ) and cyclo -(l-Trp-l-Phe) ( 10 ). The structures of these compounds were established by extensive spectroscopic investigation, as well as by detailed comparison with literature data. This is the first report to discover pyridine, pyrimidine and diketopiperazines from the genus of Pseudogymnoascus .

A sensitive electrochemical sensor was developed for the detection of nitro-explosives in aqueous solutions based on thin molecularly imprinted polydopamine films. Dopamine was identified in silico, based on DFT (density functional theory) calculations with the ωB97X-D/6-31G* basis set, as the best functional monomer and electropolymerized via cyclic voltammetry (CV) in the presence of carboxylic acid-based structural analogues ('dummy' templates) for two model nitro-explosives: TNT (2,4,6-trinitrotoluene) and RDX (Research Department eXplosive, 1,3,5-trinitroperhydro-1,3,5-triazine). This approach afforded a homogenous coverage of gold electrodes with imprinted films of tunable thickness. The electropolymerized molecularly imprinted polydopamine films allowed for a 10 5 -fold sensitivity improvement over a bare gold electrode based on tracking the redox peaks of the targets by CV. This improved sensitivity is ascribed to the ability of the MIP to concentrate its target in proximity to the transduction element. The MIP films showed reproducible binding in phosphate buffer (10 mM, pH 7.4), with a dynamic range from 0.1 nM to 10 nM for both TNT and RDX and an increased selectivity over closely related structural analogues., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Understanding transport behavior of graphitic carbon nitride (g-C 3 N 4 ) in porous media plays an important role in preventing its possible causing the underground environmental problems. The transport behavior of g-C 3 N 4 in porous media were investigated by packed column experiments at different flow rates, ionic strengths (ISs), pHs and multivalent cations. The experimental results showed that the transport ability of g-C 3 N 4 decreased with the IS increasing, and most of the g-C 3 N 4 was retained in the sand column for the IS greater than 0.0001 M. The flow rate had little effect on the transport behavior of g-C 3 N 4 , and the recovery of g-C 3 N 4 increased slightly with increasing flow rate. In addition, the migration ability of g-C 3 N 4 under acidic conditions was drastically reduced compared with neutral alkaline conditions. Moreover, it was found that 1.51%, 30.33%, 34.91%, and 60.54% of g-C 3 N 4 was retained in the column when g-C 3 N 4 was leached through the quartz sand column at Al 3+ , Ca 2+ , Mg 2+ , and K + , which was consistent with the Schulze-Hardy rule. Finally, FTIR spectrum showed that the infrared absorption peak of the g-C 3 N 4 mixed quartz sand were shifted to certain degrees under different conditions, which confirmed that hydrogen bond was formed in the transport of carbon nitride with the quartz sand surface. This study provides a new perspective on the role of hydrogen bond in the transport and fate of nanomaterials., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this study, we investigated the physicochemical properties of soil, and the diversity and structure of the soil ammonia-oxidizing archaea (AOA) community, when subjected to fertilizer treatments for over 35 years. We collected soil samples from a black soil fertilization trial in northeast China. Four treatments were tested: no fertilization (CK); manure (M); nitrogen (N), phosphorus (P), and potassium (K) chemical fertilizer (NPK); and N, P, and K plus M (MNPK). We employed 454 high-throughput pyrosequencing to measure the response of the soil AOA community to the long-term fertilization. The fertilization treatments had different impacts on the shifts in the soil properties and AOA community. The utilization of manure alleviated soil acidification and enhanced the soybean yield. The soil AOA abundance was increased greatly by inorganic and organic fertilizers. In addition, the community Chao1 and ACE were highest in the MNPK treatment. In terms of the AOA community composition, Thaumarchaeota and Crenarchaeota were the main AOA phyla in all samples. Compared with CK and M, the abundances of Thaumarchaeota were remarkably lower in the MNPK and NPK treatments. There were distinct shifts in the compositions of the AOA operational taxonomic units (OTUs) under different fertilization management practices. OTU51 was the dominant OTU in all treatments, except for NPK. OTU79 and OTU11 were relatively abundant OTUs in NPK. Only Nitrososphaera AOA were tracked from the black soil. Redundancy analysis indicated that the soil pH and soil available P were the two main factors that affected the AOA community structure. The abundances of AOA were positively correlated with the total N and available P concentrations, and negatively correlated with the soil pH., (© 2019 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

Cyanobacterial blooms increasingly impair inland waters, with the potential for a concurrent increase in cyanotoxins that have been linked to animal and human mortalities. Microcystins (MCs) are among the most commonly detected cyanotoxins, but little is known about the distribution of different MC congeners despite large differences in their biomagnification, persistence, and toxicity. Using raw-water intake data from sites around the Great Lakes basin, we applied multivariate canonical analyses and regression tree analyses to identify how different congeners (MC-LA, -LR, -RR, and -YR) varied with changes in meteorological and nutrient conditions over time (10 years) and space (longitude range: 77°2'60 to 94°29'23 W). We found that MC-LR was associated with strong winds, warm temperatures, and nutrient-rich conditions, whereas the equally toxic yet less commonly studied MC-LA tended to dominate under intermediate winds, wetter, and nutrient-poor conditions. A global synthesis of lake data in the peer-reviewed literature showed that the composition of MC congeners differs among regions, with MC-LA more commonly reported in North America than Europe. Global patterns of MC congeners tended to vary with lake nutrient conditions and lake morphometry. Ultimately, knowledge of the environmental factors leading to the formation of different MC congeners in freshwaters is necessary to assess the duration and degree of toxin exposure under future global change.

Nitrogen-containing compounds are important components in human breath. However, their origins have not yet been clearly understood. In this study, a modified electrospray ionization (ESI) source coupling with quadrupole time-of-flight mass spectrometry has been used for breath analysis. Fourteen nitrogen-containing compounds were identified in mouth-exhaled breath, and 10 of them were from the oral cavity and oropharynx. Moreover, 8 of these nitrogen-containing compounds were recognized as endogenous metabolites. This result provides important clues for exploring the biological origins of these nitrogen-containing compounds. Observation of the ion suppression phenomenon also indicates that breath analysis should be carried out after clearing of the oral cavity and oropharynx, or directly through nose-breathing to eliminate the influence of those nitrogen-containing compounds from the oral cavity.

The use of supplements for weight loss and in sports as pre-workout (ergogenic) products is widespread. Many of these supplements were found to contain active components, which were not claimed on the products labels. A validated liquid chromatography high-resolution mass spectrometry quadrupole time-of-flight (LC-QToF-MS) method was developed for the simultaneous analysis of 111 amine-based compounds belonging to ergogenics, anorectics and other active components including phenethylamines (amphetamines, ephedrines), sibutramine or yohimbine. This method involves the detection of [M+H] + ions and the separation was achieved using a C 18 column, water/acetonitrile gradient as the mobile phase. The method was validated for linearity, repeatability, accuracy, stability, system suitability, limits of quantification (LOQ) and limits of detection (LOD). The limits of detection were in the range from 0.001-0.5 μg/mL. The validated method was applied to the analysis of twenty-seven weight loss and ergogenic dietary supplements. Two-thirds of the supplements contained compounds that were not listed on the product's label. These include several phenethylamines (PEA) such as demelverine, hordenine, N, N-dimethyl-phenethylamine, synephrine, N-methyl-β-phenethylamine, and methylsynephrine. In addition, the PEA mimics such as dimethylamylamine, dimethylbutylamine other stimulants including fursultiamine, evodiamine, phenibut and theophylline were also observed. One or more of the ingredients listed on the labels were not detected in forty-four percent of the products analyzed. Positive identification was based on retention time, accurate mass and fragment ions in comparison with the respective reference standards. Development of such methods is anticipated to be of aid to regulatory agencies for the identification of undeclared exogenous components that are found in many dietary supplement products., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Phenolic and nitrogenous compounds from different styles craft beers were identified by high performance liquid chromatography and mass spectrometry in order to stratify beer samples according to their style. For this, an exploratory assessment relying on Linear Discriminant Analysis was performed. Fifty-seven phenolic compounds were reported and twelve of them were found for the first time in beer: benzoic acids, 2,4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, dimethoxybenzoic acid; phenolic acid conjugates, 3-p-coumaroylquinic acid, 4-p-coumaroylquinic acid, 3-feruloylquinic acid, 4-feruloylquinic acid, 5-feruloylquinic acid; flavonoids, taxifolin hexoside, quercetin dihexoside, apigenin-6,8-dipentoside, and isofraxidin hexoside. Additionally, 11 nitrogenous compounds belonging to the phenolamide class were found. Two discriminant functions were generated and allowed a satisfactory separation among all beer styles. 3-Caffeoylquinic acid, 3-p-coumaroylquinic acid, 4-p-coumaroylquinic acid, 5-caffeoylquinic acid, coumaric acid, kaempferol-3-O-rutinoside, proanthocyanidin B dimer III and proanthocyanidin B dimer V were the compounds that showed the highest capacity of discriminate the beer styles (IPA, Lager and Weiss)., (Copyright © 2019. Published by Elsevier Ltd.)

In this study, the concentrations and distributions of nitrated polycyclic aromatic hydrocarbons (NPAHs) were characterized in the freshwater environment of a Japanese city. While the NPAHs were few in number, they were found in pg/L concentrations and the specific isomers suggested the deposition of NPAHs formed via the atmospheric transformation of PAHs. The absence of NPAHs formed via primary combustion processes such as automobile exhaust, suggests that improvements in emission standards are being reflected in the environment, though the NPAHs formed by secondary atmospheric processes are still a significant ecotoxicological threat. The stability of the NPAHs was also examined in spiked freshwater matrices. There was a significant decrease in spiked NPAHs over this period, suggesting that they were either being sorbed or transformed and are therefore not long lived in the freshwater environment. This indicates that the NPAHs found in freshwater samples are from recent deposition., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This study investigated the effects of frozen storage time on the quality and muscle structure in normal and pale, soft and exudative (PSE)-like pork. The meat quality of M. longissimus et lumborum (LL) was studied at 0, 3, 6, 9, 12, 15 and 18 weeks of storage at -18 °C, and M. Biceps femoris (BF) was studied at 0, 3 and 18 weeks of storage at -18 °C. Storage time affected all the measured parameters (pH, thaw loss, TVB-N, shear force and muscle structure). There were no differences between normal and PSE-like meat for thaw loss (%) or TVB-N (mg/100 g) values at all storage times. An initial tenderizing effect in PSE-like samples was observed at weeks 3 and 6 in LL samples, but thereafter samples became tougher during frozen storage and after 3 weeks in the BF. Storage for 6 weeks for PSE-like and 9 weeks for normal pork at -18 °C does not reduce quality., (Copyright © 2019. Published by Elsevier Ltd.)

The sea lamprey (Petromzons marinus) is a devastating invasive species that represents a significant impediment to restoration of the Laurentian Great Lakes. There is substantial interest in developing environmentally benign control strategies for sea lamprey, and many other aquatic invasive species, that employ the manipulation of semiochemical information (pheromones and chemical cues) to guide the movements of invaders into control opportunities (e.g. traps, locations for safe pesticide application, etc.). A necessary precursor to the use of semiochemicals in conservation activities is the identification of the chemical constituents that compose the odors. Here, we characterize the major nitrogenous substances from the water-soluble fraction of a skin extract that contains the sea lamprey alarm cue, a powerful repellent that has proven effective in guiding the movements of migrating sea lamprey in rivers. Nitrogenous compounds are suspected components of fish alarm cues as the olfactory sensory neurons that mediate alarm responses transduce amino acids and related compounds. A laboratory assay confirmed the behavioral activity contained in the alarm cue resides in the water-soluble fraction of the skin extract. This water-soluble fraction consisted primarily of creatine (70%), heterocyclic nitrogenous compounds (4.3%) and free amino acids (18.4%), respectively. Among the free amino acids characterized in our study, essential amino acids constituted 13% of the water-soluble fraction. Free amino acids isolated from the water-soluble fraction composed of arginine, phenylalanine, threonine, and asparagine 3.9, 2.7, 2.6 and 2.4% of the water-soluble fraction, respectively. We discuss the implications of these findings for understanding the nature and use of the sea lamprey alarm cue in conservation activities., Competing Interests: The authors have declared that no competing interests exist.

The first example of an extruded polymer film containing the pH sensitive dye bromophenol blue (BPB) is described in which the polymer encapsulated dye changes colour from yellow to blue upon exposure to basic volatile nitrogen compounds, such as those given off by fish as it spoils. The latter include: trimethylamine (TMA), dimethylamine (DMA) and ammonia (NH 3 ), and are collectively known as total volatile basic nitrogen (TVB-N). The films' colourimetric response to specific levels of TMA, as measured using absorbance spectroscopy and digital photography coupled with RGB colour analysis, is reported. The indicator is then used as a fish spoilage indicator at 22 and 4 °C, whilst at the same time a microbiological study is carried out, and in both cases the results reveal a strong correlation between the change in colour of the indicator with the concentration of bacterial colony forming units on the fish; the latter is often used as a measure of fish freshness. The correlation arises because the increase in TVB-N in head space of the package is due to the gradual bacteria-induced decomposition of the fish. The colourimetric TVB-N plastic film indicator's potential as a spoilage indicator for packaged fresh fish is discussed briefly., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Personnel in swimming pool facilities typically experience ocular, nasal, and respiratory symptoms due to water chlorination and consequent exposure to disinfection by-products in the air. The aim of the study was to investigate exposure to trichloramine and trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane, and bromoform) from the perspective of adverse health effects on the personnel at Swedish habilitation and rehabilitation swimming pools. The study included 10 habilitation and rehabilitation swimming pool facilities in nine Swedish cities. The study population comprised 24 exposed swimming pool workers and 50 unexposed office workers. Personal and stationary measurements of trichloramine and trihalomethanes in air were performed at all the facilities. Questionnaires were distributed to exposed workers and referents. Spirometry, fraction of exhaled nitric oxide (FE NO ), and peak expiratory flow (PEF) were measured. Personal and stationary measurements yielded trichloramine levels of 1-76 µg/m 3 (average: 19 µg/m 3 ) and 1-140 µg/m 3 (average: 23 µg/m 3 ), respectively. A slightly higher, but not significant, prevalence of reported eye- and throat-related symptoms occurred among the exposed workers than among the referents. A significantly increased risk of at least one ocular symptom was attributed to trichloramine exposure above the median (20 µg/m 3 ). Lung function (FVC and FEV1) was in the normal range according to the Swedish reference materials, and no significant change in lung function before and after shift could be established between the groups. Average FE NO values were in the normal range in both groups, but the difference in the values between the exposed workers and referents showed a significant increase after shift. Hourly registered PEF values during the day of the investigation did not show any unusual individual variability. In conclusion, the increased risk of developing at least one ocular symptom at personal trichloramine concentrations over 20 µg/m 3 combined with an increase in the difference in FE NO during the work shift of the exposed workers should not be neglected as an increased risk of respiratory inflammation in the habilitation and rehabilitation swimming pool environment.

In the present work, nitrous oxide emissions were estimated [mg/L] by the use of lysimeters under the closed chamber technique for a six month period. The lysimeters were classified by the type of irrigation used: one for drinking water, and the other for treated wastewater. Each lysimeter had two different types of soil (sand and clay), based on the types of soil in Chihuahua City, Mexico. An additional classification based on the depth was done (reticular and vadose zone). Each zone collected gas by the use of a closed chamber technique, allowing the samples to be taken for subsequent quantification and analysis by gas chromatography. A statistical analysis of variance (ANOVA) and principal components analysis (PCA) were conducted to identify the most influential variables or parameters in the formation of nitrous oxide. The variables that were considered for analysis were total Kjeldahl nitrogen (TKN), ammoniacal nitrogen (NH3-N), nitrate nitrogen (NO3-N), and nitrite nitrogen (NO2-N), along with meteorological parameters. In total, 58944 mg/L of N2O were emitted during the measurement period. The results showed that concentration emissions of N2O where the type of soil is sandy were smaller than those of clay soil, while the mean concentration in the vadose zone was higher than those in the reticular zone, regardless the type of soil. The parameters that showed greater influence in the N2O emissions were NO2-N and NO3-N concentrations. Temperature also played an important role in the emissions (the highest emissions were emitted during the cold months). Furthermore, denitrification appeared to be the dominant process in the production of nitrous oxide in soils. Implications: Nitrous oxide (N 2 O) emissions produced in lysimeters with two types of soil (sand and clay) at two different depths (vadose and reticular zones) using treated waste water showed that the higher emissions of N 2 O are derived from clay soils in vadose zone; it could be due to the formation of clogging that favors the formation of anoxic conditions for the denitrification process. The parameters that showed more influence in the N 2 O emissions were nitrite (NO 2 -N) and nitrate (NO 3 -N) concentrations along with the temperature.

Volatile organic compounds (VOCs) emitted from in vitro cultures may reveal information on species and metabolism. Owing to low nmol L -1 concentration ranges, pre-concentration techniques are required for gas chromatography-mass spectrometry (GC-MS) based analyses. This study was intended to compare the efficiency of established micro-extraction techniques - solid-phase micro-extraction (SPME) and needle-trap micro-extraction (NTME) - for the analysis of complex VOC patterns. For SPME, a 75 μm Carboxen®/polydimethylsiloxane fiber was used. The NTME needle was packed with divinylbenzene, Carbopack X and Carboxen 1000. The headspace was sampled bi-directionally. Seventy-two VOCs were calibrated by reference standard mixtures in the range of 0.041-62.24 nmol L -1 by means of GC-MS. Both pre-concentration methods were applied to profile VOCs from cultures of Mycobacterium avium ssp. paratuberculosis. Limits of detection ranged from 0.004 to 3.93 nmol L -1 (median = 0.030 nmol L -1 ) for NTME and from 0.001 to 5.684 nmol L -1 (median = 0.043 nmol L -1 ) for SPME. NTME showed advantages in assessing polar compounds such as alcohols. SPME showed advantages in reproducibility but disadvantages in sensitivity for N-containing compounds. Micro-extraction techniques such as SPME and NTME are well suited for trace VOC profiling over cultures if the limitations of each technique is taken into account., (Copyright © 2018 John Wiley & Sons, Ltd.)

Concentrations of amino acids and volatile compounds of a given grapevine cultivar might be altered by inter-annual climate variability and management practices such as irrigation. These compounds determine, in part, aroma and sensory characteristics of wines. The current study aimed at assessing the amino acid profile of musts and wines and the volatile composition of wines from Vitis vinifera (L.) cultivar 'Godello' grown in the Ribeiro Designation of Origin (NW Spain) under rain-fed and supplementary irrigation (SI) conditions over three years (2012-2014). Supplementary irrigation increased must titratable acidity. However, must amino acid concentrations were not significantly altered by SI. In contrast, the concentrations of ethyl lactate and geraniol were greater in wines from the SI treatment. Significant correlations between amino acids in musts and volatiles in wines were observed. Our results highlight the low impact of SI on must and wine composition, likely due to the low level of water stress experienced by Godello vines. Understanding the effects of SI on wine properties could aid to adapt management practices in the future., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Lacy phacelia (Phacelia tanacetifolia Borkh.) honey composition was screened by UHPLC-DAD-QqTOF-MS. The targeted analysis revealed 6 major nitrogen compounds including aromatic amino acids (tyrosine, phenylalanine), purine derivatives (adenine, xanthine), nucleoside (uridine) and rare non-cyanogenic cyanoglucoside, (-)-5-epi-lithospermoside ((2Z)-2-[(4R,5R,6S)-4,5-dihydroxy-6-(β-d-glucopyranosyl)oxycyclohex-2-en-1-ylidene]acetonitrile). Their identity was confirmed by different analytical tools: HRMS, co-chromatography with standard compound or comprehensive NMR experiments. All the compounds, except amino acids, were reported and determined in honey for the first time. The amount of the compounds was quantified in 16 unifloral phacelia samples: adenine (18.45 ± 4.63 mg/kg), xanthine (10.53 ± 2.98 mg/kg), uridine (42.84 ± 9.26 mg/kg), tyrosine (14.66 ± 10.22 mg/kg), (-)-5-epi-lithospermoside (70.61 ± 31.37 mg/kg) and phenylalanine (20.41 ± 11.99 mg/kg). The (-)-5-epi-lithospermoside content is significantly correlated with P. tanacetifolia pollen percentage (R 2  = 0.5612, p < 0.001) and it is proposed as a potential marker of botanical origin for phacelia honey., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The fate of inorganic nitrogen species has been studied for the first time in electro-Fenton (EF) conditions in acid media. A redox cycle is first obtained and validated with a kinetic model in synthetic solution and highlights the removal of nitrite that is quickly oxidized into nitrate while the reduction conditions are sufficient to reduce nitrate into ammonium cation. However, NH 4 + and gaseous nitrogen accumulate in such solution. The study in reclaimed municipal wastewater emphasize the removal of NH 4 + with formation of chloramines in the presence of initial chloride ions, a species widely present in wastewater effluent. Contrastingly, NO 3 - remain constant all along the electrolysis even after 2.1 Ah L -1 . The oxidation conditions were not sufficient to produce perchlorate while chlorate accumulated in solution. Therefore, it limits the use of EF for direct use for drinking water purpose but could be considered as complementary treatment for wastewater reuse applications., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Microbially-mediated soil N mineralization and transformation are crucial to plant growth. However, changes in soil microbial groups and various N components are not clearly understood. To explore the relationship between soil N components and microbial communities, we conducted an in-situ experiment on two typically planted forest species, namely, Sibirica Apricot (SA) and Prunus davidiana Franch (PdF) by using closed-top polyvinyl chloride tubes. Changes in soil inorganic N, organic N (ON) fractions, and levels of microbial phospholipid fatty acids (PLFAs) were measured bimonthly from April 2012 to April 2013. Microbial PLFAs and the concentrations of easily-available microbial biomass N (MBN; ~60 mg kg-1), soluble ON (SON; ~20 mg kg-1), and inorganic N were similar between the two soils whereas the ON (~900 mg kg-1) and its major part total acid-hydrolyzable N (HTN; ~500 mg kg-1), were significantly different (p < 0.05) in most months (5/6 and 4/6; respectively). The canonical correlation analysis of soil N fractions and microbial parameters indicated that the relationship between total PLFAs (total biomass of living cells) and NH4+-N was the most representative. The relative contributions (indicated by the absolute value of canonical coefficient) of NH4+-N were the largest, followed by NO3--N and MBN. For the HTN component, the relative percentage of hydrolyzable amino acid N and ammonium N decreased markedly in the first half of the year. Canonical variation mainly reflected the relationship between ammonium N and bacterial PLFAs, which were the most sensitive indicators related to soil N changes. The relative contributions of HTN components to the link between soil microbial groups and HTN components were ammonium N > amino acid N > amino sugar N. Observations from our study indicate the sensitivity of soil N mineralization indicators in relation to the temporal variation of soil microbial groups and N fractions., Competing Interests: The authors have declared that no competing interests exist.

Four lactic acid bacteria (LAB) strains isolated from straw silages on the Tibetan Plateau were characterized, and their effects on the fermentation quality of Italian ryegrass (Lolium multiflorum Lam.) at different temperatures (10°C, 15°C and 25°C) were studied. These LAB isolates were evaluated using the acids production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. All the isolates (M1, LM8, LO7 and LOG9) could grow at 5-20°C, pH 3.5-7.0 and NaCl (3.0%, 6.5%). Strains M1, LM8, LO7 and LOG9 were identified as Lactobacillus plantarum, L. coryniformis, Pediococcus pentosaceus and P. acidilactici, respectively, by sequencing 16S ribosomal DNA. The four isolates were added to Italian ryegrass for ensiling for 30 days at various temperatures. Compared with the corresponding control, inoculating with isolates M1, LM8 and LO7 could improve the silage quality of Italian ryegrass at low temperatures, indicated by significantly (P < 0.05) higher lactic acid (LA) contents and ratios of lactic acid/acetic acid (LA/AA), and significantly (P < 0.05) lower pH and ammonia nitrogen/total nitrogen (AN/TN). Compared with other isolates, LM8 performed better at 10°C and 15°C, indicated by the higher (P < 0.05) LA content and ratio of LA/AA, and the lower (P < 0.05) pH and AN/TN., (© 2017 Japanese Society of Animal Science.)

We studied the formation of four nitrogenous DBPs (N-DBPs) classes (haloacetonitriles, halonitromethanes, haloacetamides, and N-nitrosamines), as well as trihalomethanes and total organic halogen (TOX), after chlorination or chloramination of source waters. We also evaluated the relative and additive toxicity of N-DBPs and water treatment options for minimisation of N-DBPs. The formation of halonitromethanes, haloacetamides, and N-nitrosamines was higher after chloramination and positively correlated with dissolved organic nitrogen or total nitrogen. N-DBPs were major contributors to the toxicity of both chlorinated and chloraminated waters. The strong correlation between bromide concentration and the overall calculated DBP additive toxicity for both chlorinated and chloraminated source waters demonstrated that formation of brominated haloacetonitriles was the main contributor to toxicity. Ozone-biological activated carbon treatment was not effective in removing N-DBP precursors. The occurrence and formation of N-DBPs should be investigated on a case-by-case basis, especially where advanced water treatment processes are being considered to minimise their formation in drinking waters, and where chloramination is used for final disinfection., (Copyright © 2017. Published by Elsevier B.V.)

We report the investigation of the hydrothermal liquefaction products of the Spirulina platensis microalgae by using the Fourier transform ion cyclotron resonance mass spectrometry. The hydrothermal liquefaction produced two fractions: one with boiling temperature below 300℃ and the dense residue that remained in the reactor. It was observed that N 2 and N classes of compounds that dominate in the positive ESI Fourier transform ion cyclotron resonance spectra for both fractions, and that the light fraction is considerably more saturated then the heavy one. The performed hydrogen/deuterium exchange reaction indicated the presence of the onium compounds in the bio-oil.

The interactive effect of inoculants and dried jujube powder (DJP) on the fermentation and nitrogen fraction (PA, PB1, PB2, PB3 and PC fractions) of alfalfa silage was investigated. Three of the Lactobacillus plantarum inoculants (LP1, LP2 or LP3) were used. The DJP was added at rates of 0, 3, 6, 9, 12 or 15% of the whole fresh forage. The combination of DJP and inoculants decreased the pH value and ammonia nitrogen content and increased the PC portion. As the DJP ratio increased, there was a peak in lactic acid : acetic acid ratio (12% of DJP ratio) and PB2 fraction (9% of DJP ratio) while the PA content decreased linearly. The LP1 and LP2 had the highest lactic acid content. Inoculants decreased the PB1 portion of true protein. The LP1 treated silage had the highest acetic acid content with the lowest lactic acid : acetic acid ratio and had lower PB3 and PC and higher PB2 than LP2 or LP3 treated silages. The result showed that the application of DJP or inoculants have positive effect on the fermentation, nutrition and N fraction value in the high moisture alfalfa silages, and the combination of DJP and inoculants preserves best., (© 2016 Japanese Society of Animal Science.)

This study aimed to evaluate the effect of liquid brewer's yeast (LBY) addition on chemical composition and fermentation quality of mixture of LBY and cassava pulp (CVP) with rice straw (RS) in different ratios during preservation periods. Four mixtures of LBY, CVP and RS were made, that is mixture ratio of LBY : CVP : RS of 0% LBY, 20% LBY, 35% LBY and 50% LBY were 0:70:30, 20:50:30, 35:35:30 and 50:20:30 as fresh matter, respectively. The bags were opened at weeks 0, 1, 2, 4 and 8 after storage. The contents of dry matter, organic matter, crude protein (CP), ether extract (EE), neutral detergent fiber and acid detergent fiber ranged 36.4-40.0, 88.9-90.8, 4.0-12.0, 1.1-1.3, 58.8-61.6 and 37.6-40.0, respectively, and the contents of CP and EE increased and the other components decreased in proportion to LBY inclusion (P < 0.01). 50% LBY had the highest (P < 0.05) pH (4.81) and ammonia nitrogen per total nitrogen (NH 3 -N/TN) (7.40%) and the lowest V-score (90.3). Propionic and butyric acid contents were 0.01% or lower in each mixture and storage period. There were rapid pH decrease and NH 3 -N/TN increase during the first week of the storage period. The increases of NH 3 -N/TN and acetic acid content and decreases of pH, lactic acid content and V-score during the preservation were more drastic as LBY inclusion increased. Although higher proportion of LBY produced higher CP and lower fiber contents in the mixture, attention should be paid for the reduction of fermentation quality during longer storage periods., (© 2016 Japanese Society of Animal Science.)

Rice straw and sweet potato vines are the main by-products of agricultural crops, and their disposal creates problems for the environment in the south of China. In order to establish an easy method for making rice straw silage successfully, experiments were conduct to evaluate fermentation quality and nutritive value of rice straw silages ensiled with or without sweet potato vine. Paddy rice straw (PR) and upland rice straw (UP) were ensiled alone or with sweet potato vines (SP) by a ratio of 1:1 (fresh matter basis), over 3 years. Compared with rice straw silages ensiled alone, the mixed-material silages (PR + SP, UR + SP) showed higher fermentation quality with lower propionic acid content and NH 3 -N ratio of total N, and higher (P < 0.05) concentrations of lactic acid and acetic acid, resulting in decrease (P < 0.05) of dry matter loss and higher (P < 0.05) in vitro ruminal dry matter digestion. When the fermentation quality, chemical composition and in vitro rumen fermentation characteristics were considered, ensiling would be an effective way of utilization of rice straw and sweet potato vines in the regions where rice and sweet potato are harvested at same season, and the sweet potato vines have the potential to improve rice straw fermentation quality with low water soluble carbohydrate content in south of China., (© 2016 Japanese Society of Animal Science.)

High-salt content seaweed sauces were prepared for the first time using nori (Pyropia yezoensis) by fermentation and characterized. Components and taste of the two nori sauces (NSs) prepared separately were compared with those of soy and fish sauces. The NSs were rich in total nitrogen compounds (1.5 g N/100 ml on average) and potassium (880 mg/100 g), and had a unique free amino acid composition (e.g., taurine 617 mg/100 g), explaining their unique taste as evaluated by a taste sensing system. As for their food function, inhibitory activity of angiotensin-converting enzyme was observed. As for their food safety, arsenic was detected at a 0.8 mg/100 g level in total, but inorganic arsenic was not detected (<0.05 mg/100 g) and not regarded as a problem. Allergy-causing substances contained in wheat, soy beans, and crustaceans were not detected (<0.1 mg/100 g) with NSs. These results suggest that the nori sauce has a high potential as a novel nutritional source for humans., (Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Plant nanobionics aims to embed non-native functions to plants by interfacing them with specifically designed nanoparticles. Here, we demonstrate that living spinach plants (Spinacia oleracea) can be engineered to serve as self-powered pre-concentrators and autosamplers of analytes in ambient groundwater and as infrared communication platforms that can send information to a smartphone. The plants employ a pair of near-infrared fluorescent nanosensors-single-walled carbon nanotubes (SWCNTs) conjugated to the peptide Bombolitin II to recognize nitroaromatics via infrared fluorescent emission, and polyvinyl-alcohol functionalized SWCNTs that act as an invariant reference signal-embedded within the plant leaf mesophyll. As contaminant nitroaromatics are transported up the roots and stem into leaf tissues, they accumulate in the mesophyll, resulting in relative changes in emission intensity. The real-time monitoring of embedded SWCNT sensors also allows residence times in the roots, stems and leaves to be estimated, calculated to be 8.3 min (combined residence times of root and stem) and 1.9 min mm -1 leaf, respectively. These results demonstrate the ability of living, wild-type plants to function as chemical monitors of groundwater and communication devices to external electronics at standoff distances.

The characteristics of malodor released from piggery excreta samples were investigated by measuring their emission concentrations both before and after such treatments as composting or aeration from field sites. These samples were then collected from field sites and brought into the lab for analysis with the aid of the dynamic flux chamber method. The dominating compounds in the emissions were reduced sulfur compounds, phenol, and indole. The results were examined in terms of two key odor indices: odor intensity (OI) and odor activity values (OAVs), after being grouped by some criteria. When the odor contribution in the composting facility was assessed by the OAV value, methanethiol (53.1%), trimethylamine (TMA) (25.5%), and skatole (10.1%) were dominant in the pretreatment facilities, while skatole (64.7%) and p-cresol (27.9%) in the post-treatment specimens. Likewise, in the liquid treatment facility, hydrogen sulfide (47.4%), p-cresol (26.9%), and skatole (20.2%) were dominant in the pretreatment, while only p-cresol (73.6%) in the post-treatment. In comparison to the composting facility, the liquid treatment facility proved to be more efficient in the treatment of diverse hog-barn-related odorants.

We evaluated the enhancement of cured meat taste during maturation by sensory analysis. We focused on the heat-stable sarcoplasmic fraction (HSSF) to identify the factors related to cured meat taste. Because the dry matter of HSSF contained more than 30% nitrogen, nitrogen compounds such as free amino acids, small peptides and adenosine triphosphate-related compounds seemed to be the important components of HSSF. The samples cured with HSSF for 2 h exhibited the same taste profile as ones cured without HSSF for 168 h. Therefore, the changes in the amount and fractions of nitrogen compounds were examined in HSSF during incubation from 0 to 168 h. The concentration of hypoxanthine (Hx) gradually increased, while inosine-5'-monophosphate decreased during the incubation. The samples cured with pickles containing various concentrations of Hx were subjected to sensory analysis. The addition of Hx, in a dose-dependent fashion, enhanced cured meat taste by maturation for 2 h. It was concluded that Hx is essential for the enhancement of cured meat taste., (© 2016 The Authors. Animal Science Journal published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Animal Science.)

A technological system was developed for efficient nitrogen removal from real digester supernatant in a single reactor with shortened aeration to increase the economical aspects of wastewater treatment. The supernatant (600 mg TKN/L, low COD/N ratio of 2.2) was treated in batch reactors with aerobic granules (GSBRs) to test how one, two, or three non-aeration phases and acetate pulse feeding in the cycle affect the morphological and microbial properties of biomass. Introduction of one non-aeration phase in the cycle increased nitrogen removal efficiency by 11 % in comparison with constantly aerated GSBR. The additional non-aeration phases did not diminish the efficiency of ammonia oxidation but did favor nitrification to nitrate. Acetate pulse feeding in the reactor with three non-aeration phases raised the efficiency of nitrogen removal to 77 %; in parallel, the number of denitrifiers possessing nosZ genes and performing denitrification to N 2 increased. Ammonia was oxidized by aerobic and anaerobic ammonia-oxidizing bacteria and heterotrophic nitrifiers (Pseudomonas sp. and Alcaligenes faecalis) that coexisted in granules. Azoarcus sp., Rhizobium sp., and Thauera sp. were core genera of denitrifiers in granules. An increase in the number of non-aeration phases diminished EPS content in the biomass and granule diameters and increased granule density.

To assess pollution levels of major inorganic nitrogen species and their atmospheric deposition input to sensitive ecosystems in Sichuan Basin, southwest China, ambient concentrations of oxidized (NO y  ∼ NO 2 , HNO 3 , NO 3 - ) and reduced (NH x  = NH 3 , NH 4 + ) nitrogen species were collected at two urban sites during four one-month periods, each in a different season from July 2014 to April 2015. Estimated annual mean concentration of NO y was 20.3 and 13.5 μg N m -3 in Chengdu and Wanzhou, respectively, and NH x was 16.9 and 13.6 μg N m -3 , respectively. Back trajectory cluster analysis indicated that high levels of NO y and NH x in Chengdu were mainly caused by local emissions while those in Wanzhou were caused by both the local emissions and long-range transport of pollutants. On annual basis, NO 2 contributed the most to NO y , followed by NO 3 - and HNO 3 , accounting for 87.5%, 10.5% and 2.0%, respectively, of NO y in Chengdu, and 91.4%, 6.9% and 1.7%, respectively, in Wanzhou. NH 3 was the predominant contributor to NH x , contributing 65.6% and 72.2% in Chengdu and Wanzhou, respectively. Dry deposition fluxes were estimated using the inferential method with measured ambient concentrations and modelled dry deposition velocities. The total inorganic nitrogen dry deposition flux was estimated to be 21.4 and 8.5 kg N ha -1  yr -1 , with 44.3% and 41.4% from NO y in Chengdu and Wanzhou, respectively. NO 2 and NH 3 each contributed about 80% of NO y and NH x dry deposition, respectively. Wet deposition was only collected in Wanzhou, where the annual wet deposition of NO 3 - and NH 4 + was 4.5 and 15.7 kg N ha -1  yr -1 , respectively. The total wet plus dry deposition was 28.7 kg N ha -1  yr -1 in Wanzhou with 72.2% from reduced nitrogen. Therefore, controlling NH 3 emissions from agricultural, traffic, waste containers and sewage system sources would be effective to reduce the total nitrogen deposition in the Sichuan Basin area., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: This study investigated trichloramine exposure and prevalence of respiratory and ocular symptoms among Swedish indoor swimming pool workers., Methods: Questionnaires were distributed to pool workers and referents. Lung function and fraction of exhaled nitric oxide (FeNO) were measured before and after work. Exposure to trichloramine and trihalomethanes was measured over work shifts., Results: The mean personal trichloramine exposure was 36 μg/m. Significantly more exposed workers reported ocular and nasal symptoms. There were significant differences between groups in FeNO change following work, with exposed showing increased FeNO, which grew when analyses included only nonsmokers., Conclusions: The findings indicate that indoor swimming pool environments may have irritating effects on mucous membranes. FeNO data also indicate an inflammatory effect on central airways, but the clinical relevance is unclear. Low trichloramine levels found in this study were not associated with health effects.