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The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The continued efficient use of whey as a fermentable substrate to produce alcoholic beverages will benefit from improving the measurement of key components relevant to the fermentability of whey. One component of fermentation that is not well studied in whey is the concentration of fermentable nitrogen, either as free amino nitrogen (FAN) or yeast-assimilable nitrogen (YAN). Fermentable nitrogen in media is essential for yeast cells to replicate. Insufficient concentrations of FAN or YAN to support the growing yeast population can result in sluggish or "stuck" fermentations. We evaluated 3 common methods of fermentable nitrogen determination and compared them for use in whey fermentation systems, based on ninhydrin, nitrogen by o- phthalaldehyde (NOPA), and formaldehyde pH (Sørensen titration) values. Each measurement method was evaluated independently using standard addition curves and compared for overall accuracy using paired t -tests (α = 0.05). Although the formaldehyde pH method showed high precision, it did not measure nitrogen accurately, as it overestimated YAN in whey by up to 6 times relative to other tests. The ninhydrin and NOPA methods both showed accuracy for fermentable nitrogen determination in whey based on analysis of standardized nitrogen sources. We concluded that either the ninhydrin FAN or NOPA YAN method may be used to determine the fermentable nitrogen content in whey. This is expected to improve the ability of producers to use whey as a fermentation medium. [ABSTRACT FROM AUTHOR]

[Display omitted] • Apart from prevalent species, unique fungi (Chaetomium) dominated aerated landfill. • Fungal community structure was correlated to ammonia content in the landfill refuse. • Fungi contributed to the main nitrification (62.71 ∼ 100 %) in the absence of ammonia. • Fungi showed a stronger preference for organic nitrogen as nitrification substrate. • Fungi utilized nitrite for nitrate production with a rate 4.65 mg L−1 d−1 in SALR F. The application of in-situ aeration technology in landfills has been reported to promote fungal growth, but the community diversity and function of fungi in the aerated landfill system remain unknown. This study firstly investigated an in-situ aerated remediation landfill site to characterize the fungal community diversity in refuse. And to further reveal the fungal involvement in the nitrogen cycling system, laboratory-scale simulated aerated landfill reactors were then constructed. The results in the aerated landfill site showed a significant correlation between fungal community structure and ammonia nitrogen content in the refuse. Dominant fungi in the fungal community included commonly found environmental fungi such as Fusarium , Aspergillus , Gibberella , as well as unique fungi in the aerated system like Chaetomium. In the laboratory-scale aerated landfill simulation experiments, the fungal system was constructed using bacterial inhibitor, and nitrogen balance analysis confirmed the significant role of fungal nitrification in the nitrogen cycling process. When ammonia nitrogen was not readily available, fungi converted organic nitrogen to nitrate, serving as the main nitrification mechanism in the system, with a contribution rate ranging from 62.71 % to 100 % of total nitrification. However, when ammonia nitrogen was present in the system, autotrophic nitrification became the main mechanism, and the contribution of fungal nitrification to total nitrification was only 15.96 %. Additionally, fungi were capable of directly utilizing nitrite for nitrate production with a rate of 4.65 mg L−1 d−1. This research article contributes to the understanding of the importance of fungi in the aerated landfill systems, filling a gap in knowledge. [ABSTRACT FROM AUTHOR]

Nitrogen source assimilation is important for the biological functions of fungi, and its pathway has been deeply studied. Aspergillus oryzae mutants defective in nitrogen source assimilation are known to grow poorly on Czapek-Dox (CD) medium. In this study, we found an industrial strain of A. oryzae that grew very poorly on a CD medium containing sodium nitrate as a nitrogen source. We used media with various nitrogen components to examine the steps affecting the nitrogen source assimilation pathway of this strain. The strain grew well on the CD medium supplied with nitrite salt or ammonium salt, suggesting that the strain was defective in nitrate assimilation step. To ascertain the gene causing the defect of nitrate assimilation, a gene expression vector harboring either niaD or crnA of A. oryzae RIB40 was introduced into the industrial strain. The industrial strain containing the crnA vector recovered its growth. This is the first report that a mutation of crnA causes poor growth on CD medium in an industrial strain of A. oryzae , and crnA can be used as a transformation marker for crnA deficient strains. • An nitrate assimilation mutant was firstly found in industrial Aspergillus oryzae strains. • A vector harboring either wild type niaD or crnA was constructed and introduced. • The industrial strain containing the crnA vector recovered its growth. • Several industrial strains were found to possess the same sequence as mutated crnA. [ABSTRACT FROM AUTHOR]

The aims of this study were (1) to identify genomic regions associated with a N efficiency index (NEI) and its composition traits and (2) to analyze the functional annotation of identified genomic regions. The NEI included N intake (NINT1), milk true protein N (MTPN1), milk urea N yield (MUNY1) in primiparous cattle, and N intake (NINT2+), milk true protein N (MTPN2+), and milk urea N yield (MUNY2+) in multiparous cattle (2 to 5 parities). The edited data included 1,043,171 records on 342,847 cows distributed in 1,931 herds. The pedigree consisted of 505,125 animals (17,797 males). Data of 565,049 SNPs were available for 6,998 animals included in the pedigree (5,251 females and 1,747 males). The SNP effects were estimated using a single-step genomic BLUP approach. The proportion of the total additive genetic variance explained by windows of 50 consecutive SNPs (with an average size of about 240 kb) was calculated. The top 3 genomic regions explaining the largest rate of the total additive genetic variance of the NEI and its composition traits were selected for candidate gene identification and quantitative trait loci (QTL) annotation. The selected genomic regions explained from 0.17% (MTPN2+) to 0.58% (NEI) of the total additive genetic variance. The largest explanatory genomic regions of NEI, NINT1, NINT2+, MTPN1, MTPN2+, MUNY1, and MUNY2+ were Bos taurus autosome 14 (1.52–2.09 Mb), 26 (9.24–9.66 Mb), 16 (75.41–75.51 Mb), 6 (8.73–88.92 Mb), 6 (8.73–88.92 Mb), 11 (103.26–103.41 Mb), 11 (103.26–103.41 Mb). Based on the literature, gene ontology, Kyoto Encyclopedia of Genes and Genomes, and protein-protein interaction, 16 key candidate genes were identified for NEI and its composition traits, which are mainly expressed in the milk cell, mammary, and liver tissues. The number of enriched QTL related to NEI, NINT1, NINT2+, MTPN1, and MTPN2+ were 41, 6, 4, 11, 36, 32, and 32, respectively, and most of them were related to the milk, health, and production classes. In conclusion, this study identified genomic regions associated with NEI and its composition traits, and identified key candidate genes describing the genetic mechanisms of N use efficiency-related traits. Furthermore, the NEI reflects not only its composition traits but also the interactions among them. [ABSTRACT FROM AUTHOR]

In this work, we proposed a two-phase hydrothermal synthesis approach to fabricate high-curvature bulk surface with engineered in-plane defects. Organic or supercritical solvents were introduced as a second immiscible media to alter MoS 2 hydrothermal growth. Two mixing scenarios, depending on the ratio of organic solvent to aqueous solution. In the case of the organic solvent isolated by aqueous solution, the growing slabs change its original direction when getting contact with the organic droplets. In the scenario that aqueous droplets dispersed in organic solvent, MoS 2 slabs grow along the curved interfaces of aqueous droplets. Experimental results showed that the curved basal planes were generated in the two cases and more curvatures were introduced in the second phase under adequate mixing energy. Higher curvature degree led to a better catalytic performance. Compared to decalin, supercritical heptane that can facilitate the dispersion of the precursor-containing aqueous solution into homogeneous nano-size reaction cells, showed a great capacity to generate highly curved slabs. MoS 2 synthesized with supercritical solvent exhibits the highest activity among the investigated catalysts. The catalysts were characterized by SEM, XRD, XAFS, TPR and nitrogen adsorption analysis. The results were proved by the theoretical calculations that the formation energy (E form) of sulfur vacancy (V S) on curly structure possesses a reduction of 0.19 eV comparing with planar MoS 2 monolayer. The curved structure can facilitate the surface V S generation by depopulating the occupied bonding states of corresponding Mo-S bonds. This work provides an effective approach to create basal defects on the MoS 2 to promote its catalyst activity. [Display omitted] • In-plane defects were fabricated by a novel two-phase hydrothermal synthesis. • More defects (curvatures) are created when organic solvent is in majority. • Compared to organic solvent, supercritical solvent generates more curly structure. • The formation energy of sulfur vacancy on curly structure is lower than planar MoS 2. • MoS 2 synthesized with supercritical solvent exhibits the highest activity. [ABSTRACT FROM AUTHOR]

A proton energy suitable for elastic backscattering spectrometry for nitrogen composition analysis of transition metal nitride thin films on a silicon substrate was suggested. Conditions under which the backscattering yield from nitrogen is as high as possible, and that from silicon as low as possible is preferred. The ratio of the backscattering yield of the nitrogen at the surface to that of the silicon in the same channel, was calculated for the proton energies between 1.0 and 2.5 MeV with an interval of 20 keV. It was shown that a proton energy of 1.62–1.64 MeV is the most suitable not only considering the above-mentioned ratio, but also with regard to the energy dependence of the scattering cross section and an easy check of the proton energy during the measurements. [ABSTRACT FROM AUTHOR]

• Mudstone top-seals such as silty-shales possess a wide range of grain sizes and so have complex heterogeneity of pore structure. • The combination of two fluid invasion methods allow a full range of pore body and pore throat diameter representation. • Shale mineralogy strongly influence the pore system and exposed surface area. Fine-grained lithologies above CCS reservoirs cannot automatically be assumed to be mineralogically stable, or high quality top-seals to highly pressured CO 2 as saline aquifer have previously contained hydrostatically pressured water. We have investigated the mineralogy, pore systems and surface area characteristics of the Lower Cretaceous Rodby Shale, the caprock to the Captain Sandstone at the UK's planned Acorn/Goldeneye CCS site. Rodby Shale core was logged and analysed by XRD, light microscopy, and SEM. Grain size was measured using laser particle size analysis. Mercury intrusion porosimetry and nitrogen adsorption analysis were used to characterise the pore network. The Rodby is smectite-rich and contains abundant calcite as well as quartz silt with small quantities of chlorite and plagioclase. Calcite was sourced from benthic microfossils, locally recrystallised to create a pore-filling cement. The mean pore throat and pore body diameter are about 17 nm putting the Rodby in the mesopore range and suggesting a predominance of slit-like pores. There are three lithofacies in the Rodby Shale: (i) high surface area clay-rich shale, (ii) low surface area calcite-rich shale, (iii) intermediate surface area quartz-rich. if the second lithotype encountered CO 2 , then the resulting calcite dissolution would lead to increasing surface area of the remaining shale. The Rodby Shale has good potential to be an effective barrier for CO 2 escape, based on assessments of diffusion rate and post-breakthrough advection rate as well as stability and sealing assessments. [ABSTRACT FROM AUTHOR]

Plants are widely existing in the environments and have been considered as potential sentinel species of toxic chemicals′ exposure. In this study, the deadly toxic chemicals of three nitrogen mustards (NMs, including NH1, NH2 and NH3) were selected as the investigated targets. First, the reactivities of common endogenous plant components with NMs were examined in vitro. Then, the model plant Nicotiana benthamiana Domin was exposed to NMs. Three γ-aminobutyric acid–nitrogen mustard adducts (GABA–NMs) were identified in the living plant by high resolution mass spectrometry and comparison with the synthesized references. A sensitive detection method with the limits of quantification of 0.0500 ng mL−1 was developed using ultrahigh performance liquid chromatography–triple quadrupole mass spectrometry. The GABA–NMs could be detected after 120 days of the exposure and even in the dead leaves without obvious decrease. Furthermore, 20 different plant species grown in diverse climate zones were exposed to HN1, and the adduct of GABA–HN1 was identified in all the leaves. The results showed the good universality and specificity of GABA–NMs as plant biomarkers for NMs exposure. This work provides a new approach for the pollution investigation of toxic chemicals through analysing biomarkers in plant materials. [Display omitted] • Three novel adducts of nitrogen mustards with GABA were found in exposed plants. • The adducts were unambiguously identified through reference synthesis. • A sensitive LC–MS quantitation method was established for retrospective analyses. • The adducts serve as excellent plant biomarkers for nitrogen mustards exposure. • The biomarkers exhibit long detection windows and universal applicability. [ABSTRACT FROM AUTHOR]

A method for simultaneous determination of nitrogen content and 15N isotope abundance in plants was established by Elemental analysis-gas isotope ratio mass spectrometry. Taking poplar leaves and l -glutamic acid as standards, nitrogen content was determined using the standard curve established by weighted least squares regression between the mass of nitrogen element and the total peak height intensity at m/z 28 and 29. Then the 15N isotope abundance was calculated with the peak height intensity at m/z 28 and 29. Through the comparison of several sets of experiments, the impact of mass discrimination effect, tin capsule consumables, isotope memory effect, and the quality of nitrogen on the results were assessed. The results showed that with a weight of 1/x2, the standard curve has a coefficient of determination (R2) of 0.9996. Compared to the traditional Kjeldahl method, the measured nitrogen content deviated less than 0.2 %, and the standard deviation (SD) was less than 0.2 %. Compared to the sodium hypobromite method, the 15N isotopic abundances differed less than 0.2 atom%15N, and the SD was less than 0.2 atom% 15N. The established method offers the advantages of being fast, simple, accurate, and high throughput, providing a novel approach for the simultaneous determination of nitrogen content and 15N isotope abundance in plant samples. [Display omitted] • Plant nitrogen content and 15N isotope abundance with mass spectrometry. • Plant nitrogen content analysis with weighted least squares regression. • Determination of nitrogen content and 15N abundance using peaks at m/z 28 and 29. • Simultaneous acquisition of two key parameters in a single sampling process. • Accurate and precise nitrogen content and 15N isotope abundance analysis method. [ABSTRACT FROM AUTHOR]

Livestock is often considered as a potential hub of circularity but evidence of circularity benefits for the sustainability of agro-food-waste systems (AFWS) is lacking in the literature. This study assessed the consequences of livestock based circularity on nutrient and carbon management in the AFWS of an isolated tropical island. A substance flow analysis of nitrogen (N), phosphorus (P), and carbon (C) cycles was conducted at the level of the AFWS of French Reunion Island. Eight livestock based circularity levers and their combinations, aimed at increasing recycling between sub-sectors, reducing losses at the sub-sector level, and adjusting inputs to needs at the sub-sector level, were compared to the baseline situation using four indicators: (i) N, P and C cycling indexes as circularity indicators, (ii) N and P use efficiency, (iv) N and P self-sufficiency and (iv) humified C inputs to cultivated soils as a proxy of potential additional C storage. Simulating livestock based scenarios improved the cycling index by from +0% to +17% depending on the substance and scenario considered. These increases in AFWS circularity were positively correlated with an increase in AFWS N and P use efficiency, but not necessarily with an increase in the humified C inputs to cultivated soils. The combination of all livestock based scenarios increased the AFWS N, P, and C cycling index by +12%, +17%, and +4% respectively, AFWS N and P use efficiency increased by respectively, +13% and +26%, and humified C inputs to cultivated soils by +6%. The study shows that the benefits of circularity levers differ with the substance and emphasizes the importance of considering multiple substances simultaneously to improve the accuracy of assessments of different management strategies. This study provides a reference method to compare circularity strategies within AFWS and to assess their consequences for food system sustainability. In particular, the proposed method can help determine (i) the most effective strategies and (ii) the potential co-benefits or trade-offs between different strategies, depending on the substances considered. [Display omitted] • Nitrogen, phosphorus, and carbon cycles decoupled in the agro-food-waste system of Reunion Island. • 8 livestock-based circularity levers modeled and grouped in 3 types. • All livestock based circularity levers improve AFWS nutrient use efficiency. • Only some of the levers also improve carbon return to cultivated soils. • The benefits of circularity depend on the substance and type of lever considered. [ABSTRACT FROM AUTHOR]

Pseudomonas sp. ZHL02, removing nitrogen via ammonia nitrogen (NH 4 +) → hydroxylamine (HN 2 OH) → nitrite (NO 2 −) → nitrate (NO 3 −) → NO 2 − → nitric oxide (NO) → nitrous oxide (N 2 O) pathway was employed for getting in-depth information on the heterotrophic nitrification-aerobic denitrification (HNAD) pathway from carbon oxidation, nitrogen conversion, electron transport process, enzyme activity, as well as gene expression while sodium succinate, sodium citrate, and sodium acetate were utilized as the carbon sources. The nitrogen balance analysis results demonstrated that ZHL02 mainly removed NH 4 +-N through assimilation. The carbon source metabolism resulted in the discrepancies in electron transport chain and nitrogen removal between different HNAD bacteria. Moreover, the prokaryotic strand-specific transcriptome method showed that, amo and hao were absent in ZHL02, and unknown genes may be involved in ZHL02 during the HNAD process. As a fascinating process for removing nitrogen, the HNAD process is still puzzling, and the relationship between carbon metabolism and nitrogen metabolism among different HNAD pathways should be studied further. [Display omitted] • Pseudomonas sp. ZHL02 mainly removed NH 3 through assimilation in the HNAD process. • Carbon metabolism was crucial for nitrogen removal of Pseudomonas sp. ZHL02. • Pseudomonas sp. ZHL02 via NH 4 +.→ HN 2 OH → NO 2 − → NO 3 − → NO 2 − → NO → N 2 O pathway conduct HNAD process. [ABSTRACT FROM AUTHOR]

The carbon‒oxygen balance has always been problematic in constructed wetlands (CWs), putting pressure on stable and efficient nitrogen removal. In this study, a novel partial siphon operational strategy was developed to further optimize the carbon and oxygen distributions of a partially saturated vertical flow CW (SVFCW) to enhance nitrogen removal. The removal performances of the partial siphon SVFCW (S-SVFCW) were monitored and compared with those of the SVFCWs at different partial siphon depths (15 cm, 25 cm and 35 cm) in both the warm and cold seasons. The results showed that the partial siphon operating strategy significantly facilitated the removal of ammonia and total nitrogen (TN) in both the warm and cold seasons. When the partial siphon depth was 25 cm, the S-SVFCWs had the highest TN removal efficiency in both the warm (71%) and cold (56%) seasons, with an average improvement of 46% and 52%, respectively, compared with those of the SVFCWs. The oxidation‒reduction potential (ORP) results indicated that richer OPR environments and longer hydraulic detention times were obtained in the S-SVFCWs, which enriched the denitrification bacteria. Microbial analysis revealed greater nitrification and denitrification potentials in the unsaturated zone with enriched functional genes (e.g., amo_AOA , amo_AOB , nxr A and nir K), which are related to nitrification and denitrification processes. Moreover, the strengthening mechanism was the intensified oxygen supply and carbon utilization efficiency based on the cyclic nitrogen profile analysis. This study provides a novel partial siphon operational strategy for enhancing the nitrogen removal capacity of SVFCWs without additional energy or land requirements. [Display omitted] • A partial siphon strategy created periodic redox conditions in partial-unsaturated zone. • A partial siphon strategy promoted oxygen supply and carbon utilization abilities in VFCWs. • A partial siphon strategy in VFCWs increased TN removal by 40 % compared to the control. • At low temperature, 25 cm siphon depth improved TN removal by 52 % compared to the control. • A partial siphon strategy enriched DNB population of the unsaturated zone from 17.6 % to 34.5 %. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two components of deformation density, including kinetic energy pressure and orbital relaxation have been analyzed. • The components of deformation density applied on nitrogen clusters N x (X = 4–14) to investigate the steric and attractive parts of intramolecular interaction in the context of depletion and accumulation of electron density. • Topological analysis of electron deformation density is performed to find steric paths and critical points responsible for intramolecular interactions in the nitrogen clusters. • It is shown that relaxation interaction dominates steric interaction via two languages: First, sum of eigenvalues of relaxation is more than that of steric interaction; and second, the total deformation density distribution is similar to relaxation rather than steric interaction. Electron deformation density analysis were performed for ten nitrogen clusters N X (X = 4–12,14), where multiple types of fragmentations were considered for each cluster as interaction between a single isolated nitrogen molecule and the rest of cluster. Two components of electronic deformation density including steric or kinetic energy pressure and orbital relaxation were analyzed to reveal deformation density distributions and the corresponding displaced charges as quantitative description. Results show dominance of relaxation over steric interaction from both qualitative and quantitative displaced charges standpoints. Topological analysis of deformation density is also accomplished and critical points and steric paths were identified. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar addition synchronously retained carbon and nitrogen during DGW composting. • The mechanism of biochar-enhanced carbon and nitrogen co-conservation is revealed. • Biochar inhibited CO 2 production and promoted carbon fixation to conserve carbon. • Nitrification and ammonia assimilation played vital roles in nitrogen retention. To elucidate the mechanism of biochar addition on carbon and nitrogen retention during distilled grain (DGW) composting, this study investigated the losses of carbon and nitrogen and functional genes related to carbon and nitrogen metabolisms between biochar-treated and control composts. The addition of biochar significantly increased carbon and nitrogen retention by 13.5% and 33.8%, respectively. The difference in core carbon metabolism genes indicated that biochar addition inhibited CO 2 release and promoted carbon fixation during the later composting phase, leading to improved carbon retention. Nitrogen metabolism analysis indicated that biochar addition suppressed early-phase ammoniation and late-phase denitrification and promoted nitrification and ammonia assimilation during the later stages of composting, thereby preserving nitrogen. During the later composting phase, biochar addition enhanced carbon–nitrogen coupling metabolism activity, leading to the synchronous retention of carbon and nitrogen. These findings elucidate the mechanism of biochar addition on carbon and nitrogen retention during DGW composting. [ABSTRACT FROM AUTHOR]

• An autotrophic system was built by integrating anammox and SCN--denitrification. • The one-stage coupled system could simultaneously remove SCN- and nitrogen. • The concentration of SCN- in the one-stage coupled system could reach 100 mg/L. • Thiobacillus_denitrificans was responsible for SCN- degradation. • The degradation pathway of SCN- was the cyanate pathway. The coupled process of anammox and reduced-sulfur driven autotrophic denitrification can simultaneously remove nitrogen and sulfur from wastewater, while minimizing energy consumption and sludge production. However, the research on the coupled process for removing naturally toxic thiocyanate (SCN-) is limited. This work successfully established and operated a one-stage coupled system by co-cultivating mature anammox and SCN--driven autotrophic denitrification sludge in a single reactor. In this one-stage coupled system, the average total nitrogen removal efficiency was 89.68±3.33 %, surpassing that of solo anammox (81.80±2.10 %) and SCN--driven autotrophic denitrification (85.20±1.54 %). Moreover, the average removal efficiency of SCN- reached 99.50±3.64 %, exceeding that of solo SCN--driven autotrophic denitrification (98.80±0.65 %). The results of the 15N stable isotope tracer labeling experiment revealed the respective reaction rates of anammox and denitrification as 106.38±10.37 μmol/L/h and 69.07±8.07 μmol/L/h. By analyzing metagenomic sequencing data, Thiobacillus_denitrificans was identified as the primary contributor to SCN- degradation in this coupled system. Furthermore, based on the comprehensive analysis of nitrogen and sulfur metabolic pathways, as well as the genes associated with SCN- degradation, it can be inferred that the cyanate (CNO) pathway was responsible for SCN- degradation. This work provided a deeper insight into coupling anammox with SCN--driven autotrophic denitrification in a one-stage coupled system, thereby contributing to the development of an effective approach for wastewater treatment involving both SCN- and nitrogen. [Display omitted] [ABSTRACT FROM AUTHOR]

Marine microplastics (MPs) pollution, with rivers as a major source, leads to MPs accumulation in estuarine sediments, which are also nitrogen cycling hotspots. However, the impact of MPs on nitrogen cycling in estuarine sediments has rarely been documented. In this study, we conducted microcosm experiment to investigate the effects of commonly encountered polyethylene (PE) and polystyrene (PS) MPs, with two MPs concentrations (0.3% and 3% wet sediment weight) based on environmental concentration considerations and dose-response effects, on sediment dissolved oxygen (DO) diffusion capacity and microbial communities using microelectrode system and metagenomic analysis respectively. The results indicated that high concentrations of PE-MPs inhibited DO diffusion during the mid-phase of the experiment, an effect that dissipated in the later stages. Metagenomic analysis revealed that MP treatments reduced the relative abundance of dominant microbial colonies in the sediments. The PCoA results demonstrated that MPs altered the microbial community structure, particularly evident under high concentration PE-MPs treatments. Functional analysis related to the nitrogen cycle suggested that PS-MPs promoted the nitrification, denitrification, and DNRA processes, but inhibited the ANRA process, while PE-MPs had an inhibitory effect on the nitrate reduction process and the ANRA process. Additionally, the high concentration of PE-MPs treatment significantly stimulated the abundance of genus (Bacillus) by 34.1% and genes (lip , pnbA) by 100–187.5% associated with plastic degradation, respectively. Overall, in terms of microbial community structure and the abundance of nitrogen cycling functional genes, PE- and PS- MPs exhibit both similarities and differences in their impact on nitrogen cycling. Our findings highlight the complexity of MP effects on nitrogen cycling in estuarine sediments and high concentrations of PE-MP stimulated plastic-degrading genus and genes. [Display omitted] • High PE-MP inhibited DO diffusion first and then the effect dissipated later. • MPs reduced the relative abundance of dominant microbial colonies. • Different MPs had complex effects on nitrogen cycle sub-processes. • High PE-MP exposure stimulated plastic-degrading genus and genes. [ABSTRACT FROM AUTHOR]

In this study, graphitic carbon nitride (GCN) material obtained from urea was hydrothermally doped with fluorine atoms (F-doped GCN). The resulting F-doped GCN material was designed as an electrode material for supercapacitors. Characterization of these samples was carried out by XRD, EDS, SEM, nitrogen adsorption and FTIR analyses. EDS and FTIR analyses confirmed the doping of fluorine atoms onto GCN. Nitrogen adsorption analyses supported the formation of a significant mesoporous structure with fluoride doping on GCN. The specific capacitance values of the GCN and F-doped GCN supercapacitors were calculated as 39.75 F/g and 305.72 F/g at a frequency of 0.01 Hz. A significant increase of about 7-fold in capacitance value was obtained by fluorine doping on GCN. Cycling trials of the F-doped GCN supercapacitor for up to 1000 cycles at a current density of 0.4 A/g maintain an efficiency of 86.72 %. For the supercapacitor designed from F-doped GCN material, the maximum energy density and power density were calculated as 4.26 Wh/kg and 1792 Wh/kg, respectively. [Display omitted] • The fluorine doped GCN material was designed as an electrode material for supercapacitors. • A significant increase of about 7-fold in capacitance value by fluorine doping was obtained. • The specific capacitance values of GCN and F-doped GCN were 39.75 F/g and 305.72 F/g. • Cycling trials of the supercapacitor for up to 1000 cycles maintain an efficiency of 86.72 %. • The maximum energy density and power density were 4.26 Wh/kg and 1792 Wh/kg. [ABSTRACT FROM AUTHOR]

The strain Ralstonia pickettii J4 was isolated as a novel heterotrophic nitrification - aerobic denitrification (HN-AD) and its potential in removing nitrogen was assessed. Results indicated that the optimal HN-AD efficiencies by strain J4 were 98.99 % for ammonium nitrogen (NH 4 +-N) and 88.86 % for total nitrogen, when using glucose as the optimal carbon source at 30 °C and under conditions of carbon/nitrogen ratio of 15, pH of 7, shaking speed of 100 rpm, and initial NH 4 +-N concentration of 50 mg/L. Analysis results of nitrogen balance and functional genes revealed the possible HN-AD pathway of J4: NH 4 +-N→ hydroxylamine→ nitrite nitrogen→ nitric oxide→ nitrous oxide→ nitrogen gas, without nitrite accumulation. Strain J4 significantly enhanced the nitrogen removal performance of a sequencing biofilm batch reactor by enriching the functional bacterial community involved in nitrogen removal, for instance, Thauera , Hydrogenophaga , and Flavobacterium. These findings are important for providing bioaugmentation sources regarding nitrogen removal of wastewater treatment. [Display omitted] • A novel HN-AD bacterium was isolated and identified as Ralstonia pickettii J4. • J4 could perform a short-cut nitrification and aerobic denitrification in wastewater. • The functional genes nap A, nir S, nor B, and nos Z were successfully amplified by PCR. • J4 has efficient potential for nitrogen removal without NO 2 --N accumulation. • J4 facilitated the enrichment of functional microbes involving in HN-AD in SBBR. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnetic molecularly imprinted sorbent specific towards 2-phenethylamine was proposed. • Morphology and structure of magnetic molecularly imprinted sorbent were characterized. • Effective analytical strategy for cocoa products analysis was elaborated. • Levels of 2-phenethylamine were determined in eighteen cocoa and chocolate samples. • Adsorption mechanism was explained by computational and isotherm studies. The main aim of this study was to design, develop, and apply magnetic molecularly imprinted polymer (MMIP) during sample pretreatment before liquid chromatography tandem mass spectrometry (LC-MS/MS) 2-phenylethylamine determination in cocoa powder and chocolate samples. The morphology and structure of MMIP , obtained from methacrylic acid (monomer) and trimethylolpropane trimethacrylate (cross-linker) were characterized using scanning electron microscopy, nitrogen sorption analyses, infra-red spectroscopy, X-ray diffraction measurements, vibrating-sample magnetometry, and thermogravimetry analyses. The analyte adsorption mechanism on MMIP was studied using computational simulation. The magnetic solid phase extraction procedure on MMIP was optimized, resulting in a relative matrix effect of 6.2 % for cocoa powder and 2.8 % for chocolate. The LC-MS/MS quantified the 2-phenethylamine in eighteen cocoa powder and chocolate samples, showing a concentration range between 2.4 and 8.7 μg g−1. [ABSTRACT FROM AUTHOR]

Dendritic mesoporous silica nanoparticles (DMSN) provide a high diversity and complexity regarding their pore structure. Herein, we present results related to electron tomographic reconstruction and nitrogen sorption analysis of DMSNs with different pore structures obtained through variation of the surfactant concentration in the synthesis. The tomograms revealed that at all DMSNs exhibit a highly porous shell structure and a denser porous core with smaller pores. The shell generally consists of dendritic silica walls forming a disordered pore system of center radially aligned mesopores. At the highest surfactant concentration these mesopores had a roughly conical geometry, providing a highly accessible pore network. Nitrogen sorption revealed a broad pore size distribution, in agreement with this conical mesopore shape. The mesopore dimensions obtained through reconstruction were in good agreement with the pore size distribution obtained by nitrogen sorption. For intermediate and low surfactant concentrations, different pore geometries were observed in the reconstruction with increasing restriction of the pore volume towards the outer surface of the particles by branching of large pores into smaller ones. Nitrogen sorption analyses support these observations by featuring an increasing hysteresis with decreasing surfactant concentration in the synthesis, which indicates that the accessible pore volume is restricted by smaller mesopores towards the rim of the particles. [Display omitted] • The influence of surfactant concentration on the pore structure of dendritic, mesoporous silica nanoparticles has been detailed through TEM tomography. • The mesopore structure and size at the particle rim is defined by the surfactant concentration. • The adsorption NLDFT kernel as well as the BJH model applied to the adsorption isotherm give a good estimate of the mesopore size distribution of DMSN. [ABSTRACT FROM AUTHOR]

Despite of several decades lasting extensive research of bioactive and bioresorbable glasses the systematic parametrization and determination of the key factors affecting porosity and thermomechanical characteristics still remains challenging. Here, we present silica-phosphate glasses, with the composition 70SiO 2 –20P 2 O 5 –(10- x)CaO– x TiO 2 (mol%; x = 0, 2.5, 5, and 7.5), prepared by sol-gel method and reinforced by titanium dioxide via titanium isopropoxide (TTIP) incorporation which demonstrated tunable variation of porosity from micro-to macro-region and superb mechanical integrity during the calcination process. The presence of 7.5 mol% TiO 2 promotes dimensional stability up to 1000 °C as investigated by thermomechanical analysis. The XRD showed the dominant presence of silicon phosphate [Si(P 2 O 7)], titanium phosphate [Ti(P 2 O 7)] and calcium phosphates [β-Ca(P 2 O 6) and γ- Ca 2 (P 2 O 7)]. The effect of TiO 2 doping on the multiscale morphology and porosity was investigated by means of SEM, MIP, μCT, N 2 adsorption and USAXS/SAXS. Increasing TiO 2 content leads to the formation of open porosity up to 70 vol% and drives the formation of a refined interconnected macroporosity of 2–30 μm. In contrast, mesoporosity with a dominance of 3–6 nm pores decreases in all samples with increasing TiO 2 content. USAXS/SAXS revealed an increase in primary particle size with increasing TiO 2 content which is in good agreement with the nitrogen physisorption analysis showing that microporosity decreases with increasing TiO2 content. [Display omitted] • The reinforcement of silica-phosphate glass with titanium dioxide via titanium isopropoxide. • The increasing TiO 2 content led to the formation of open porosity 70 vol%. • The presence of TiO 2 drives a formation of a fully interconnected framework at a macroscale. • Micro-/mesoporosity decreases with increasing TiO 2 content. • USAXS/SAXS profiles indicated the hierarchical morphology of sol-gel glasses. [ABSTRACT FROM AUTHOR]

• MABRs were exposed to different aeration patterns and scouring frequencies. • Oxygen dynamics were analyzed at different depths during intermittent aeration. • Aeration and scouring had a major impact on the oxygen profiles within the biofilms. • N 2 O emissions differed between the different MABR operation strategies. This study investigated the effects of aeration and scouring strategies on the performance of Membrane Aerated Biofilm Reactors (MABRs) and the distribution of oxygen and nitrous oxide in the biofilm. Four flat sheet MABRs were operated with synthetic feed under different conditions: two with intermittent aeration (iMABR) and two with continuous aeration (cMABR). Scouring was induced by bubbling dinitrogen gas through the reactor bulk at low and high frequencies (LF and HF). In the iMABRs, a partial nitritation biofilm initially developed, but the biofilm adapted to the aeration strategy over time and became nitrifying. The cMABRs directly developed a nitrifying biofilm without a significant phase of partial nitritation. Limiting oxygen availability improved the overall performance with regards to total nitrogen (TN) removal by providing a better environment for anaerobic ammonium oxidation (Anammox) while limiting complete nitrification. Oxygen profiles were measured in the iMABR over time at different biofilms depths, showing that intermittent aeration led to various oxygen concentrations and temporal variations in the oxygen availabilities at different depths of the biofilm. Also, N 2 O emissions from the MABRs differed greatly between the different systems, but still remained lower compared to other reactor configurations for nitrogen removal, making the MABR technology a worthy alternative. The results showed large differences between the operating strategies of the MABRs and can help to gain more insight into the specific properties of MABRs for nitrogen removal. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Mn-N co-doped biochar for removing BPA (351 mg/g) was prepared. • High specific surface area was helpful to reveal more Mn-N adsorption sites. • The main mechanisms were pore filling, hydrophobic effect and π-π-EDA interaction. • DFT proved that nitrogen configurations and manganese promoted adsorption. A novel porous manganese and nitrogen co-doped biochar (Mn-N@SBC) was synthesized via one-step pyrolysis, utilizing loofah agricultural waste as the precursor and NaHCO 3 as the activator. The behavior of bisphenol A adsorbed on Mn-N@SBC was evaluated using static batch adsorption experiments. Compared to direct manganese-nitrogen co-doping, co-doping based on NaHCO 3 activation significantly increased the specific surface area (231 to 1027 m2·g−1) and adsorption capacity (15 to 351 mg·g−1). Wide pH (2–10) and good resistance to cation/anion, humic acid and actual water demonstrated the robust adaptability of Mn-N@SBC to environmental factors. The significantly reduced specific surface area after adsorption, adverse effects of ethanol and phenanthrene on the removal of bisphenol A, and theoretically predicted interaction sites indicated the primary adsorption mechanisms involved pore filling, hydrophobicity, and π-π-electron-donor–acceptor interaction. This work presented an approach to create high-efficiency adsorbents from agricultural waste, offering theoretical and practical guidance for the removal of pollutants. [ABSTRACT FROM AUTHOR]

Panax notoginseng often faces varying levels of light stress during its growth, which can hinder efforts to improve its yield and quality. Nitrogen (N) and potassium (K) are known play important role in photosynthesis, while the synergistic effect and mechanism in enhancing the resistance to light stress of P. notoginseng have yet to be well understood. In this study, field experiments and pot trials were conducted to investigate the regulatory effects of the combined application of N and K on N allocation in P. notoginseng leaves under light stress, as well as on metabolic products of photosynthesis and the accumulation of saponin. Results showed that compared with medium light (ML: optimal light intensity, 450 μmol/m2/s), both low light (LL: 60 μmol/m2/s) and high light (HL: 800 μmol/m2/s) stress significantly reduced the net photosynthetic rate (Pn) (32.45% and 12.23%, respectively) and photosynthetic nitrogen use efficiency (PNUE) (10.01% and 19.21%, respectively) of P. notoginseng leaves. Compared with N0K0 (N: K=0.0045:0.0045 kg/m2), N1K2 (N: K=0.0225:0.045 kg/m2) treatment significantly increased Pn and PNUE under LL or HL stress in P. notoginseng , with an average increase of 52.80% and 31.61%, respectively. The allocation of carboxylation nitrogen (Ncb) and electron transport nitrogen (Net) were identified as the main limiting factors for PNUE under light stress. However, compared with N0K0, N1K2 treatment mitigated these limitations by increasing Rubisco content at an average of 0.29 ng/g FW, and adjusting the Ncb ratio by 7.31% to 21.11%, primarily through conversion of non-protein nitrogen (N np) to photosynthetic nitrogen (N psn). In addition, compared with N0K0, N1K2 regulated the activity of carbohydrate metabolism enzymes, resulting in an average increase of 25.72% in starch content and a mean decrease of 6.48% in sucrose content under LL or HL stress, ultimately promoting the accumulation of total saponins in P. notoginseng (11.95% to 29.67%). In summary, under light stress, N1K2 synergy improves LL or HL stress resistance of P. notoginseng by expanding and supplementing the N psn pool in its leaves, thereby promoting the accumulation of carbohydrate and saponins. [Display omitted] • N1K2 mitigates Pn, WUE, and Rubisco decline in light-stressed P. notoginseng. • N1K2 increases the capacity and proportion of N psn in P. notoginseng. • N1K2 promotes the conversion of N np to N psn in P. notoginseng. • There is a significant correlation between PNpsn and PNUE. • N1K2 improves P. notoginseng 's stress resistance, enhancing yield and quality. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen removal efficiencies by zeolite wetland was better than ceramists and lava. • Selective inhibition of amo B and hao gene abundance on different substrates. • Denitrification is a key pathway for nitrate removal in constructed wetland (CW) • Dissimilatory nitrate reduction process was enhanced in CW- zeolite. This study conducted an analysis of the variations in nitrogen metabolism pathways within constructed wetlands (CWs) using zeolite (CW-Z), ceramsite (CW-C), and lava (CW-L) under high concentration sulfamethoxazole (SMX) stress. The introduction of SMX hindered the formation of hydrogen bonds on the substrate surfaces; however, these surfaces still maintained a dense and thick biofilm. CW-Z exhibited superior removal efficiencies for ammonium nitrogen (NH 4 +-N) and nitrate nitrogen (NO 3 –-N) compared to CW-C and CW-L, with removal rates of 92.54 ± 2.88 % and 89.39 ± 6.74 %, respectively. Interestingly, the proportion of genes involved in nitrification, denitrification and nitrate reduction genes in CW-C (36.05 %) were higher than that in CW-C (29.81 %) and CW-L (29.70 %) but the interactions among nitrogen functional bacteria in CW-Z were much more complex. Further analysis of the nitrogen metabolism pathway indicated that under CW-Z enhanced dissimilatory nitrate reduction SMX stress, while CW-L enhanced assimilatory nitrate reduction process compared to CW-C. [ABSTRACT FROM AUTHOR]

Mesoporous γ-alumina is widely used as catalyst support in various catalytic reactions of industrial interest. However, due to the instability of γ-alumina at elevated temperatures, many efforts have been reported to inhibit the α-alumina phase transition through doping with suitable metalloids, as well as transition, post-transition, or rare-earth elements. In the present study, undoped and La-, Sn-, and B-doped alumina granules were synthesized via sol-gel/oil drop method with the aim to clarify the role of the additives and their content on the porous structure as well as on the chemical, structural, and microstructural behavior of γ-alumina. XRD and DTA/TG results demonstrated that thermal stability of transition aluminas increases more than 100 °C by 3 wt% lanthanum and tin doping; however, boron doping seems to have only negligible effect on the thermal stability. On the other hand, based on nitrogen adsorption-desorption analysis, tin and boron-doped aluminas showed a higher surface area at 750 °C (between 214.74 m2/g to 245.97 m2/g) but higher loss in the surface area after calcination at 1200 °C (between 25.45 m2/g to 8.57 m2/g). On the contrary, the 3 wt% La-doped alumina sample, with a relatively high surface area at 750 °C (227.17 m2/g), exhibited the highest surface area after calcination at 1200 °C (53.07 m2/g). 27Al MAS NMR and HRTEM studies indicated that the presence of 3 wt% La in alumina structure leads to thermal and mesoporous structure stability up to 1200 °C by inhibiting oxygen lattice restructuring. These results provide a comparative perspective of La, B, and Sn additives' behavior in γ-alumina. [ABSTRACT FROM AUTHOR]

In the present study, metal-free catalysts for efficient H 2 generation from NaBH 4 methanolysis was produced for the first time from apricot kernel shells with two-step activation. The first stage of the two-stage activation includes the production of activated carbon with the KOH agent (AKOH), and the second stage includes hydrothermally HNO 3 activation with oxygen doping (O doped AKOH + N). The hydrogen production rate (HGR) and the activation energy (Ea) of the reaction with the obtained metal-free catalyst (10 mg) were determined as 14,444 ml min−1 g−1 and 7.86 kJ mol−1, respectively. The structural and physical-chemical properties of these catalysts were characterized by XRD (X-ray diffraction), SEM (scanning electron microscopy), elemental CHNS analysis, FT-IR (Fourier transform infrared spectroscopy), and nitrogen adsorption analysis. Also, the reusability results of this metal-free catalyst for H 2 production are promising. [Display omitted] • O doped metal-free catalysts based on carbonaceous sample was prepared. • Metal-free catalysts were used to obtain H 2 from NaBH 4 methanolysis. • HGR obtained with O doped metal-free catalysts was 14,444 ml min−1g−1. • Ea value was 7.86 kJ mol−1. [ABSTRACT FROM AUTHOR]

Background Emerging evidence suggests that a dietary protein intake higher than the current recommended dietary allowance of 0.8 g/kg body weight (BW)/d may be needed to maintain optimal muscle mass, strength, and function in older adults. However, defining optimal protein intake in this age group remains a challenge. Objective In this study we sought to describe the dietary protein intake in frail, prefrail, and robust older Taiwanese adults Methods Data for 1920 older adults were collected from the Nutrition and Health Survey in Taiwan from 2014 to 2017. Dietary intake was assessed using the 24-h recall method. Frailty was determined using the modified Fried's criteria. Body composition was assessed using DXA. Sex-specific dietary protein intakes, measured as values/kg of BW, fat-free mass (FFM), and lean mass (LM), were estimated for the 3 age groups (65–69, 70–79, and ≥80y) and the 3 frailty levels. Results In both males (P for trend = 0.034) and females (P for trend = 0.015), there were significant downward trends for protein intake/kg of BW with the severity of frailty. The age-adjusted protein intake/kg of BW was still significant in males (P for trend = 0.009), but no longer in females. This phenomenon was also seen for protein intake at lunch and dinner but not at breakfast. Age-adjusted trends for protein intake/kg FFM or LM were not significant in either sex. The median protein intake in robust older males and females was 1.21 and 1.19 g/kg BW/d, respectively, and the mean intakes were even higher. Conclusion Median protein intake in robust Taiwanese older adults was approximately 1.2 g/kg BW/d, with higher mean values. The protein adequate intake in Taiwanese older adults was higher than the current recommended daily allowance (RDA) level but within the RDA range derived from the state-of art indicator amino acid oxidation technique. [ABSTRACT FROM AUTHOR]

Nitrogen balance (NB) experiments allow calculation of N retention in the body by subtracting N excreted in feces (NF), urine (NU) and milk (NM) from N intake (NI). In a previous study, we found that NB data from experiments with lactating dairy cows were generally high and, in the current meta-analysis, we update our earlier study with experiments from the last 2 decades and investigate probable causes of error. A total of 83 publications, with 86 experiments and 307 dietary treatments, were selected from top-ranked scientific journals that reported all NB components. The NB and NB components were analyzed by linear regression with a model that used NI as an independent variable and experiment as a random effect. The NF, NU and NM each represented 27 to 34% of NI, and the remaining N accumulated in the body was equal to 38.5 g/d (overall SD = 43.2 g/d). Retained N (as g/d or % of NI) increased linearly with NI, and this led to unlikely high N retentions, especially at high NI. Both NF and NU (g/d) increased with increasing NI, and we assume that some N in feces and urine were unaccounted. Only ~22% of experiments measured N in wet feces samples and, when analysis used dry samples, no mention of corrections due to potential volatile N losses during drying were reported. No experimentalists preserved feces immediately to prevent volatilization during collection. Moreover, ~27% of experiments estimated urine volumes by concentration of creatinine in spot samples, and in these experiments, NU was ~12% lower than those where total urine was collected (168 vs. 191 g/d). Only 40 experiments reported the volume and concentration of acids used for urine preservation, 33 furnished incomplete information, and the remainder did not describe the urine preservation method. In conclusion, the results of NB experiments using lactating dairy cows overestimate N retention, and the losses of N from feces and urine are the most probable reason. [ABSTRACT FROM AUTHOR]

Sebacate (SB) molecules were incorporated into Ca Al layered double hydroxides (CaAL-LDH) using a hydrothermal method. The resulting products underwent characterization through X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. To investigate the release kinetics and thermodynamics of the corrosion inhibitor, total organic carbon analysis (TOC) was employed. A comparison was made with CaAl-LDH prepared without corrosion inhibitors, in which nitrates were the primary anions within the layered clay structure. An assessment of anion exchange between nitrates and chlorides was conducted using total nitrogen analysis (TN). The SB anion comprised approximately 49.2% of the total dried powder synthesized, with a maximum release efficiency of around 86.7% fitting a Langmuir model. For the evaluation of the corrosion inhibition effect on steel surfaces, electrochemical impedance spectroscopy, potentiodynamic polarization, and scanning vibrating electrode technique were employed. The corrosion inhibition impact was ascribed to the liberation of SB anions from the CaAl-LDH pigments, accompanied by alkalinization stemming from partial particle dissolution. Additionally, the incorporation of organic molecules notably enhanced the stability of pigments in aqueous solutions compared to similar ones hosting nitrates. These findings suggested that CaAl-LDH pigments have potential as nanocontainers for organic inhibitors, showing promising prospects in the field of corrosion research. [Display omitted] • Synthesis of CaAl-LDHs particles with sebacate intercalated. • Sebacate anionic exchange with chlorides is efficient at 86.7%. • Organic molecule intercalation gives improved stability in water. • Steel corrosion protection is provided by chloride trapping and inhibitor release. [ABSTRACT FROM AUTHOR]

• We present a two-step BN based GSA for NRTM to identify its dominant process. • A real modeling case of EPIC-Nitrogen2D was used for demonstration. • The results show that the dominant processes were diverse for different outputs. Process-based nitrogen reactive transport models (NRTMs) are vital tools for simulating complex nitrogen reactive transport processes in soils and groundwater to reduce nutrient loss and contamination risk. To develop and improve these models, global sensitivity analysis (GSA) is used to identify key model parameters and processes. Because existing GSA approaches focus mainly on model parameters and not model processes, in this study, we developed a two-step GSA method to improve our understanding of model processes. First, we applied the Morris method to identify less influential parameters. Then, we developed a Bayesian network (BN)-based GSA method to identify the dominant processes for different model predictions. The BN-GSA method accounts for the hierarchical uncertainty in the structure of the model system and flexibly groups uncertain inputs into processes based on their characteristics. The two-step GSA method was applied to a real-world nitrogen reactive transport model with 68 uncertain parameters in three different climate scenarios. The results show that the dominant processes differed for various nitrogen and agricultural outputs; thus, different processes should be emphasized based on specific modeling purposes. [ABSTRACT FROM AUTHOR]

Epiphytic orchids acquire nutrients elements, including nitrogen, from the atmosphere. However, the nitrogen form preferred by epiphytic orchids Cymbidium tracyanum and adaptive mechanisms that underlie nitrogen metabolism remain unclear. In this study, we determined which nitrogen form the C. tracyanum prefers, and identified adaptive strategies and molecular pathways activated during nitrogen metabolism. For this purpose, we measured the physiological and morphological responses to different ratios of nitrate and ammonium (NO 3 −/NH 4 + = 1:0, 3:1, 1:1, 1:3, 0:1) and used transcriptome analysis to identify genes differentially expressed in response to these nitrogen forms. Physiological and morphological measures of plant growth (i.e., net photosynthetic rate, biomass accumulation, leaf area, root elongation and branching) were highest in plants treated with nitrate. Furthermore, C. tracyanum plants treated with nitrate had a higher root/mass ratio and a lower leaf/mass ratio. Transcriptome analysis identified that several key genes (NRT1.1–2 , NRT1.4–4 , NRT1.7–2 , and CLC-G-2) highly expressed in plants treated with pure nitrate. These genes may be involved in the absorption and transportation of nitrate, and in auxin transportation from leaf to root in C. tracyanum. Our findings suggest that the nitrogen form preferred by C. tracyanum is nitrate and that nitrate alters both root and leaf traits via several molecular pathways, including the plant hormone signal transduction pathway and MAPK signaling pathway. We speculate that the preference of C. tracyanum for nitrate as a nitrogen form may be a result of long-term adaptation to epiphytic habitat via the regulation of leaf and root traits. • Cymbidium tracyanum prefer nitrate during plant vegetative growth. • Plants treated with nitrate had higher net photosynthetic rate, biomass accumulation, leaf area, and root development. • Plants treated with nitrate had a higher root/mass ratio and a lower leaf/mass ratio. • NRT1.1-2 , NRT1.4-4 , NRT1.7-2 , and CLC-G-2 may be involved in the absorption and transportation of nitrate. • We speculate that the preference of C. tracyanum for nitrate may be a result of long-term adaptation to epiphytic habitat. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHA) are bioplastics which are well known as intracellular energy storage compounds and are produced in a large number of prokaryotic species. These bio-based inclusions are biodegradable, biocompatible and environmental friendly. Industrial production of, short chain and medium chain length PHA, involves the use of microorganisms and their enzymes. Priestia megaterium previously known as Bacillus megaterium is a well-recognized bacterium for producing short chain length PHA. This study focuses to characterize this bacterium for the production of medium chain length PHA, and a novel blend of both types of monomers having enhanced properties and versatile applications. Statistical analyses and simulations were used to demonstrate that cell dry weight can be derived as a function of OD 600 and PHA content. Optimization of growth conditions resulted in the maximum PHA production as: 0. 05 g. g-x. H−1, where the rate of PHA production was 0.28 g L−1. H−1 and PHA concentration was 4.94 g. L−1. This study also demonstrated FTIR to be a semi quantitative tool for PHA production. Moreover, conversion of scl-PHA to mcl-PHA with reference to time intermissions using GC-FID are shown. • Priestia megaterium showed metabolic shift in PHA production by converting PHB into mcl-PHA using two different media. • Statistical analysis optimized the C/N ratio, and concentrations of growth constituents to enhance the mcl-PHA production. • Electron microscopy evaluated the size, structure and shape of PHA granules with respect to time intervals. [ABSTRACT FROM AUTHOR]

To overcome the drawbacks of pure mesostructured titania and in particular the low thermal stability, in this study we have investigated in detail the effect of Si4+ addition on the properties of mesostructured TiO 2 prepared by combining the sol-gel process and the surfactant templating mechanism. Obtained materials have also been tested for the photodegradation of methyl orange, used as a model dye. From the SAXS and the manometry nitrogen adsorption-desorption analyses, it can be concluded that the presence of Si4+ delays the collapse of the mesopores network. Compared to the bare mesostructured TiO 2 , the XRD and Raman results show that the anatase and the rutile phases appear at higher temperature. The higher the Si4+ content, the higher the amorphous-anatase and rutile anatase-phase transition temperatures. The delay in the crystallization also allows the detection of the TiO 2 -β phase, which is an anatase phase with oxygen vacancies. These phenomena have been attributed to the « glass effect ». In that case, amorphous SiO 2 , which is formed during the synthesis, surrounds the titania particles and inhibits their growth, when the heating temperature is increased. By this way, the thermal stability of the mesostructured titania containing Si4+ is enhanced. Photocatalytic experiments highlight the importance of the presence of the anatase phase for the discoloration efficiency of the dye solution. Indeed, the increase of Si4+ leads to a clear decrease of the photodegradation efficiency. [Display omitted] • Presence of SiO 2 involves an enhancement of thermal stability. • Protector role of amorphous SiO 2 surrounding TiO 2 particles. • Stabilization of TiO 2 -β and inhibition of rutile occur in the presence of SiO 2. • Partial substitution of Ti4+ by Si4+. • Discoloration rate of the dye solution correlated to the size of the anatase crystallites. [ABSTRACT FROM AUTHOR]

Investigation of surface recombination activity of nitrogen on certain materials is crucial in the design of hypersonic re-entry vehicles. In the present work, an experimental study using a conventional shock tube facility has been conducted to investigate the phenomena of nitrogen recombination. Stagnation heat-transfer measurements were conducted behind reflected shock waves in a dissociated shock-tube flow for a mixture of 20% nitrogen and 80% argon. A platinum thin-film gauge was used to measure the stagnation heat-transfer in a shock heated gas mixture under a well-defined test condition. The surface of the heat-transfer gauge was coated with silicon dioxide (SiO 2), the principal material used in thermal protection systems (TPS) for the hypersonic vehicles. Spectroscopic analyses were performed for in-depth characterization of the initial surface condition of the test specimen. Recombination activity behavior of nitrogen was evaluated by combining the heat-transfer data with catalytic heat transfer theories. The nitrogen recombination efficiency of silicon dioxide is found to be from 0.0026 to 0.035 at surface roughness factors of 1.01 to 1.10. Compared to the oxygen recombination activity, the nitrogen recombination activity showed a more than five times higher sensitivity to the roughness factor of the SiO 2 -coated surface. • Recombination activity behavior of nitrogen on SiO 2 surface is evaluated. • Stagnation heat-transfer data are analyzed using catalytic heat-transfer theories. • Initial surface conditions of test specimen are examined by spectroscopic analysis. • Nitrogen catalytic efficiency of SiO 2 surface is deduced to be from 0.0026 to 0.035. • Nitrogen recombination is more favorable to change in SiO 2 roughness than oxygen. [ABSTRACT FROM AUTHOR]

• Acidity of HZSM-5 is controlled by mixing HZSM-5 and Na-modified HZSM-5. • Na-modification of HZSM-5 change only acidity without change textural properties. • Mixing HZSM-5 and Na-modified HZSM-5 decreases strong acid sites of catalyst with minimizing reduction of weak acid sites. • Catalyst prepared with 50 wt% HZSM-5 and 50 wt% Na-modified HZSM-5 has higher catalytic activity than conventional HZSM-5. In this study, Zeolite Socony Mobil–5 (ZSM-5) was modified by ion exchange with sodium ion to control the strong acid sites of catalyst, and the specific control of strong acid sites was carried out by mixing HZSM-5 and NaZSM-5. The characteristics of the catalyst were analyzed using X-ray diffraction, NH 3 -temperature programmed desorption, pyridine adsorption Fourier transform infrared spectroscopy, and nitrogen adsorption-desorption analysis. The catalysts were used for the catalytic reaction with methylcyclohexane under supercritical condition (500 °C and 5.0 MPa). After reaction, the liquid product was analyzed using gas chromatography-mass spectrometry, and the spent catalyst was analyzed using thermogravimetric analysis to measure coke formation. In the catalytic reaction, conventional HZSM-5 was deactivated quickly with time (59.6 % of deactivation rate), but the mixed catalyst with NaZSM-5 was deactivated more slowly than HZSM-5. In addition, the mixed catalyst having the same mass ratio for HZSM-5 and NaZSM-5 showed the lowest deactivation rate of 37.4 % after 60 min. The mixed catalyst produced 10.1 wt% coke and it was lower than HZSM-5 (12.5 wt%). The catalytic robustness of HZSM-5 could be enhanced by mixing with NaZSM-5. [ABSTRACT FROM AUTHOR]

Background Naturally occurring carbon and nitrogen stable isotope ratios [13C/12C (CIR) and 15N/14N (NIR)] are promising dietary biomarkers. As these candidate biomarkers have long tissue residence times, long-term feeding studies are needed for their evaluation. Objective Our aim was to evaluate plasma, RBCs, and hair CIR and NIR as biomarkers of fish, meat, and sugar-sweetened beverage (SSB) intake in a 12-wk dietary intervention. Methods Thirty-two men (aged 46.2 ± 10.5 y; BMI: 27.2 ± 4.0 kg/m2) underwent a 12-wk inpatient dietary intervention at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) in Phoenix, Arizona. The effects of fish, meat, and SSB intake on CIR and NIR were evaluated using a balanced factorial design, with each intake factor at 2 levels (present/absent) in a common, background diet (50% carbohydrate, 30% fat, 20% protein). Fasting blood samples were taken biweekly from baseline, and hair samples were collected at baseline and postintervention. Data were analyzed using multivariable regression. Results The postintervention CIR of plasma was elevated when diets included meat (β = 0.89, 95% CI: 0.73,1.05) and SSBs (β = 0.48, 95% CI: 0.32, 0.64). The postintervention NIR of plasma was elevated when diets included fish (β = 0.85, 95% CI: 0.64, 1.05) and meat (β = 0.61, 95% CI: 0.42, 0.8). Results were similar for RBCs and hair. Postintervention RBC CIR and NIR had strong associations with baseline, suggesting that turnover to the intervention diets was incomplete after 12 wk. Estimates of isotopic turnover rate further confirmed incomplete turnover of RBCs. Conclusions CIR was associated with meat and SSBs, and more strongly with meat. NIR was associated with fish and meat, and more strongly with fish. Overall, CIR and NIR discriminated between dietary fish and meat, and to a lesser extent SSBs, indicating their potential utility as biomarkers of intake in US diets. Approaches to make these biomarkers more specific are needed. This trial was registered at clinicaltrials.gov as NCT01237093. [ABSTRACT FROM AUTHOR]

• The synthesis of promising multifunctional material ZnIn 2 S 4 using hydrothermal method has been proposed. • Photocatalytic dye degradation and photoelectrochemical measurements revealed the photocatalytic activity of the material. • Charge storage capacity of the material has been explored for the first time to the best of our knowledge. ZnIn 2 S 4 is an important mixed metal sulfide semiconductor with multifunctional properties, endowed upon by its hierarchical structure, large surface area and porosity. In this work, hierarchical ZnIn 2 S 4.1 (ZnInS) microflowers made up of petal like nanostructures are synthesized using a simple and facile hydrothermal method. Nitrogen adsorption-desorption analysis of these microflowers showed porous structures with pores ~3 nm. This material shows a photocurrent density of 3.1 μA cm−2 and activity towards methylene blue (MB) dye degradation under direct sunlight. The sample also shows pseudocapacitive behavior with specific capacitance value of 131 F g−1 at a scan rate of 10 mV s−1. The pseudocapacitive behavior of polycrystalline ZnInS has been explored for the first time to the best of our knowledge. This study demonstrates that the single phase ZnInS is a multifunctional material for photocatalysis and electrochemical charge storage applications. [ABSTRACT FROM AUTHOR]

• Inspiration from morphogenesis to design synthetic porous silica materials. • Biomimetics combining sol–gel process and surfactant-system templating pathway. • Oil incorporation into biocompatible Kolliphor surfactant systems: control of porosity. • Swollen micelles and fine emulsions template for large mesoporous silica. • Macropores imprints of the oil droplets of the concentrated emulsions. Taking inspiration from morphogenesis, synthetic porous silica materials have been synthesized through rational designs combining the sol–gel process and the surfactant templating method. Materials have been prepared from biocompatible systems using kolliphor as surfactant. The effect of Miglyol and Myristate solubilization in the Kolliphor/water system was first investigated in detail. The phase diagram proved that only a weak fraction of these oils (≈1 wt.%) can be incorporated into the hydrophobic core of the micelles (L 1). Results also show that whatever the liquid crystal phases [direct hexagonal (H 1) and lamellar (L α)] the swelling effect take place upon addition of oil. Moreover, at low oil concentration oil-in-water fine emulsions are formulated, while at high oil concentration, oil-in-water concentrated emulsion are formulated. Starting from the various systems, porous silica materials were then synthesized. Results obtained by SAXS and nitrogen adsorption–desorption analysis show that Miglyol and Myristate can expand the mesopore size. The variations of the pore diameter have been related to the solubilization properties of the oil in the surfactant. In addition, macroporous silica could be design by using concentrated emulsions as template. This work demonstrates that synthetic silica materials can be obtained by mimic of natural processes. [ABSTRACT FROM AUTHOR]

Background: The nitrogen isotope ratio (NIR) is a promising index of traditional food intake for an Alaska Native (Yup'ik) population, which can be measured in blood and hair. However, the NIR has not been calibrated to high-quality measures of Yup'ik traditional food intake.Objectives: Our primary objective was to examine associations between intakes of Yup'ik traditional food groups, including fish, marine mammals, birds, land mammals, berries, greens, and total traditional foods, and the NIR. In an exploratory analysis, we also examined whether NIR analyzed sequentially along hair could reflect dietary seasonality.Methods: We recruited 68 participants from 2 Yup'ik communities in the Yukon Kuskokwim region of Southwest Alaska (49% female, aged 14-79 y). Participants completed 4 unscheduled 24-h food recalls over the period peak of RBC and hair synthesis preceding a specimen collection visit. The NIR was measured in RBCs ( n = 68), a proximal hair section (n = 58), and sequential segments of hair from individuals in the upper 2 quartiles of traditional food intake having hair >6 cm in length, plus 2 low subsistence participants for reference (n = 18). Diet-biomarker associations were assessed using Pearson's correlation and linear regression.Results: Intakes of fish, marine mammals, berries, and greens were significantly associated with the NIR. The strongest dietary association was with total traditional food intake (R2 = 0.62), which indicated that each 1‰ increase in the RBC NIR corresponded to 8% of energy from traditional foods. Hair NIR appeared to fluctuate seasonally in some individuals, peaking in the summertime.Conclusions: Findings support the use of the RBC and hair NIR to assess total traditional food intake in a Yup'ik population. Analyses of sequential hair NIR provided evidence of seasonality in traditional food intake, although seasonal variations were modest relative to interindividual variation. [ABSTRACT FROM AUTHOR]

The subduction of sediment connects the surface nitrogen cycle to that of the deep Earth. To understand the evolution of nitrogen in the atmosphere, the behavior of nitrogen during the subduction and melting of subducted sediments has to be estimated. This study presents high-pressure experimental measurements of the partitioning of nitrogen during the melting of sediments at sub-arc depths. For quantitative analysis of nitrogen in minerals and glasses, we calibrated the electron probe micro-analyzer on synthetic ammonium feldspar to measure nitrogen concentrations as low as 500 μg g−1. Nitrogen abundances in melt and mica are used together with mass balance calculations to determine D N(Mica/Melt) , D N(Fluid/Mica) , and D N(Fluid/Melt). Calculated partition coefficients correspond to expected values for NH 4 +, which behaves similarly to Rb+ due to its nearly identical size. Nitrogen partitioning between fluid and melt (D N(Fluid/Melt)) and fluid and bulk residue (melt+mica) (D N(Fluid/Bulk)) increase linearly with temperature normalized to pressure. This linear relationship can be used to calculate D N(Fluid/Melt) and D N(Fluid/Bulk) for slab melts from 800 to 1200 °C following: D N Fluid / Melt = 0.012 × T ° C P GPa − 2.02 and D N Fluid / Bulk = 0.04 × T ° C P GPa − 8.48. We used these partition coefficients to quantify the amount of N recycled into the mantle as 50 ± 6% of today's atmospheric N. Depending on the rate of mantle N degassing we calculated 4 different scenarios for atmospheric pN 2 evolution. All 4 scenarios estimate pN 2 to be 8–12% higher at the beginning of the Phanerozoic. These estimates diverge towards the past due to uncertainties in the mechanism and magnitude of N degassing from the mantle. Assuming degassing of N in the past was close to modern degassing rates from MORB, pN 2 was up to 40% higher at the onset of plate tectonics at 3–4 Ga. However, degassing rates were probably higher than this: assuming 10× and 20× times higher rates at the onset of plate tectonics leads to pN 2 within 20% of modern values. If N degassing from the mantle is increased to 40× the modern MORB rate, pN 2 in the Archean would have been 50% lower than today's, which is in accordance with observations from paleoatmospheric studies. [ABSTRACT FROM AUTHOR]

• A hydroxypropyl-β-cyclodextrin functionalized monolith was prepared by a simple and efficient one-pot sequential strategy. • Enantiomer separations of various kinds of chiral analytes were achieved. • This prepared monolith exhibited good reproducibility and stability. In this study, a hydroxypropyl-β-cyclodextrin (HP-β-CD) functionalized monolithic capillary column was prepared by one-pot sequential reaction for the first time. The preparation of the HP-β-CD functionalized monolithic column involves two sequential reactions in one pot: (1) the ring opening reaction between HP-β-CD and glycidyl methacrylate (GMA) catalyzed by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU); (2) the copolymerization of GMA-HP-β-CD, ethylene dimethacrylate (EDMA) and 2-acrylamido-2-methyl propane sulfonic acid (AMPS). A series of monolithic columns were successfully prepared by varying the temperature of the ring opening reaction or several copolymerization parameters (the type and composition of porogenic solvents, ratio of GMA-HP-β-CD to EDMA and polymerization temperature). Then, the morphologies and structures of the resulting monolithic stationary phases were characterized by optical microscopy, scanning electron microscopy (SEM) and nitrogen adsorption analysis. Raman spectroscopy clearly indicated the successful bonding of HP-β-CD onto the monolith. When the prepared chiral stationary phase (CSP) was applied for the separation of a set of racemic compounds by capillary electrochromatography (CEC), including racemic anticholinergic drugs, β-adrenergic drugs, meptazinol and its intermediates, satisfactory separation selectivities were obtained. Additionally, the column also showed excellent separation abilities towards four flavanone glycosides epimers. Furthermore, the prepared monolithic columns exhibited satisfactory stability and reproducibilities of retention time, resolution and column efficiency. These results demonstrated the potential and usefulness of the developed one-pot sequential strategy in the preparation of other derivatized CD functionalized monolithic columns. [ABSTRACT FROM AUTHOR]

The elemental analyzer-isotope ratio mass spectrometer (EA-IRMS) technique is widely utilized to measure the nitrogen isotope ratio (δ15N) in various environmental samples. However, this method has limitations when analyzing samples with low nitrogen content (e.g., soils, rocks and atmospheric deposition) due to significant sample dilution (>99%) before entering the ion source. To reduce sample size requirement and increase sensitivity, modifications can be made to the elemental analyzer and analytical conditions to transfer more sample gas to the ion source. In this study, we presented four modifications to the EA-IRMS instrument, including the reaction tube, water trap, gas chromatography (GC) column, and inlet splitter connected to ConFlo, along with the analytical conditions of the GC column, carrier gas flow rate, and split ratio for improving sensitivity. The results show that reducing the carrier gas flow rate from 80 to 30 mL/min increased the sensitivity of the EA-IRMS system by twofold. By increasing the split ratio from 3:2 to 3:1, the sensitivity increased from 2.32 Vs/μg N to 3.93 Vs/μg N. The optimized EA-IRMS has a sample size requirement of at least 12 μg N and a standard deviation of <0.2‰ for δ15N analysis. We found that the modifications of the GC column and water trap had a negligible influence on sample peak and measurement and thus were deemed unnecessary. The effective modifications in the study were reducing the carrier gas flow rate and increasing split ratio, which increased the concentration of the analyte gas per unit volume and more efficient sample transfer to the ion source. This upgraded method can provide crucial technical support for environmental samples with low nitrogen content. • New modified EA-IRMS method was developed for trace nitrogen isotope analysis. • The minimum nitrogen requirement was reduced from 28 μg to 12 μg. • New method can improve analysis accuracy and decrease analysis costs. • Nitrogen isotope of varied mass of standards and actual samples are consistent. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicle (UAV) hyperspectral data can provide accurate and detailed spectral information on the surface of features, leading to a better understanding of the physiological characteristics and optical properties of objects. Compared to satellite hyperspectral, UAV hyperspectral has a greater image spatial resolution, but it also collects more impurity information along with more image detail information. The nitrogen (N) content in shallow soils is of great significance for crop growth, and most of its remote sensing inversions are currently based on satellite images, whereas relatively few studies have used hyperspectral UAV images in the near-infrared band for inversions. Based on this, we propose a high-accuracy inversion model based on UAV hyperspectral imagery using an elastic net (EN) dimensionality reduction algorithm combined with a decision tree (DT) model. In this study, a hyperspectral imager carried by a drone was used to acquire the surface soil spectral data of winter wheat in the study area after sowing and fertilizing, and the measured N content of the sampled soil was determined by chemical analysis methods. We used various pre-processing methods to denoise and reduce the dimensionality of the original hyperspectral images and utilized a DT regression model to construct an inversion model of N content with different preprocessing results. Then we compared the accuracy of the models and used the optimal model to obtain the spatial distribution map of soil N content in the study area. The results show that (1) the dimensionality reduction of hyperspectral data can effectively remove redundant information and prevent data overfitting. Among them, the successive projections algorithm and correlation analysis method are more suitable for analyzing pre-processed spectral data, whereas the Lasso and EN algorithms are more suitable for processing original spectral data. (2) For the original spectral images, the EN dimensionality reduction algorithm (R2 of the EN-Unt-DT inversion model is 0.930, RMSE is 0.045) performed better than the other three algorithms. For the pre-processed spectral images, the successive projections algorithm (R2 of the SPA-Pre-DT inversion model is 0.906, RMSE is 0.055) performed better than the other three algorithms. The constructed EN-Unt-DT inversion model had the highest fitting accuracy. The research results provide a corresponding technical reference for the inversion of soil N content using UAV NIR hyperspectral data. • The FD-SNV-SG pretreatment method was chosen based on the features of the spectral curves. • Hyperspectral data were dimensionally reduced to reduce data redundancy and avoid overfitting. • Eight inversion models were built, among which the best model was EN-Unt-DT, R2 = 0.93, RMSE = 0.045. [ABSTRACT FROM AUTHOR]

• Wood was modified via controlled in-situ self-assembly Ag-PW nanospheres. • Excellent flame retardancy and durability with leach test was achieved. • Antimicrobial property was achieved via in-situ self-assembly Ag-PW nanospheres treatment. • The catalytic mechanism of Ag-PW on depolymerization route of conversion of LGO to HMF was verified by DFT calculation. • The possible adsorption mechanism of Ag-PW on wood was proposed. In this work, we present a simple and effective approach to enhance the fire safety and anti-corrosion performance of wood by forming in-situ self-assembled amphiphilic Ag-PW nanospheres (NSP) at room temperature. The morphology and acid capacity of the NSP were optimized by changing the ratio of phosphotungstic acid (HPW) and silver nitrate. The Ag-PW NSP were successfully integrated into the bulk of the wood, resulting in a durable treatment with minimal leaching. Comprehensive characterization techniques, including FTIR, XPS, XRD, SEM, TEM, and nitrogen adsorption–desorption analysis, confirmed the in-situ formation of Ag-PW NSP in the wood. The treatment exhibited low-leaching properties with only 5.89% of Ag-PW1a leaching out. The treated wood demonstrated excellent flame-retardant (FR) properties, as evidenced by a limiting oxygen index value > 28% and easy passage of the UL-94 test, with the formation of a high-density char layer. The flammable pyrolysis products released during combustion were found to be significantly altered, with a change in the depolymerization route of conversion of LGO under acid conditions to HMF, which was verified by DFT calculations. The treated wood also exhibited outstanding anti-corrosion properties, with a mass loss rate of less than 1%, compared to at least 32.3% for bare wood after the anti-white or brown-rot fungus tests. Moreover, the treated wood samples maintained their excellent FR properties even after leaching. Our study provides valuable insights for the rational design of nano-material additives for wood protection, thereby improving the usage of wood resources while mitigating health and environmental hazards. [ABSTRACT FROM AUTHOR]

A systematic first principles study is carried out to probe into the activity of graphyne supported Co 13 , Fe 13 and Ni 13 nano-clusters (NCs) towards the reduction of nitrogen (N 2) into ammonia (NH 3). Graphyne is found to highly stabilize the metal nano-clusters on its large pores through an exothermic chemisorption process. Adsorption of N 2 on the graphyne supported NCs are detected to be highly exothermic in both end-on and side-on mode configurations. N 2 becomes more activated via a higher amount of N-N bond stretching when adsorbed in side-on configuration. The activation of the N-N bond is shown to be directly proportional to the amount of charge transfer to the adsorbed N 2 molecule. Thorough analysis of the nitrogen reduction reaction (NRR) on each graphyne supported metal NC reveals that NRR starting from side-on mode N 2 adsorbed configuration prefers the enzymatic pathway though other pathways are possible at the cost of relatively higher overpotential. Only the distal pathway is energetically favoured following the end-on mode N 2 adsorbed configuration. Graphyne supported Co 13 , Fe 13 and Ni 13 NCs are shown to carry out NRR with substantially low overpotential values of 0.24 V, 0.28 V and 0.37 V respectively. The active sites located far from the graphyne substrate are found to be more selective towards NRR with low overpotential than hydrogen evolution reaction. The NCs maintain their structural stability on the graphyne surface throughout the whole reaction process via different pathways showing that graphyne is a potentially very promising substrate material to stabilize the NC electrocatalysts and to improve their electrocatalytic activities towards NRR. [Display omitted] • NRR is studied theoretically for graphyne supported Co 13 , Fe 13 and Ni 13 nano-clusters. • The interaction of the nano-clusters with the graphyne substrate is investigated. • Electronic properties of the adsorbed nano-clusters and N 2 molecules in explored. • The selectivity of the chosen electrocatalyst systems towards NRR is established. [ABSTRACT FROM AUTHOR]

In maize, nitrogen (N) stored in leaves is an important internal source for supporting subsequent growth and development. However, the regulation of N fluxes and photosynthesis and the molecular and genotypic regulations that modify them are less clear in source leaves during the vegetative stage. This knowledge is crucial for improving N use efficiency (NUE). By using 15N labeling and transcriptome methods, an analysis of the physiological and molecular basis of leaf N import and export processes and photosynthetic N use efficiency (PNUE) was conducted in two maize hybrids (XY335 and XY696) with different stay-green characteristics during the vegetative stage. Leaf N import and export in XY696 were 45% and 33% greater than those in XY335. However, the PNUE in XY335 was 17% greater than that in XY696 due to the higher net photosynthetic rate (A) and lower SLN. Correspondingly, the chlorophyll content and photosynthesis-related enzyme (PEPc, PEPck, PPDK) activities increased by 18∼30% in XY335. Transcriptome analysis indicated that the expression levels of several N and carbon metabolism-related genes encoding Rubisco, PEPc, Nir, GS and AS were significantly increased or decreased in XY696 in parallel with enzyme activities. Moreover, there was a large difference in the expression abundance of genes encoding nitrate/nitrite transporters and transmembrane proteins. Our results suggest that two hybrids modulate leaf N fluxes and photosynthesis differently by altering gene expression and enzyme activities. Our study contributes to understanding leaf N fluxes and PNUE regulation and serves as a crucial reference for NUE improvement in maize breeding research. [Display omitted] • Leaf N import and export in XY696 were greater compared to XY335. • XY335 showed a higher PNUE as results of high A and low SLN. • Photosynthetic enzyme activities and chlorophyll content were increased in XY335. • Rubisco, NiR, GS and AS changed in transcript level in parallel to activity level. [ABSTRACT FROM AUTHOR]

[Display omitted] • Significant removal capability of inorganic N was detected in strain DN3. • N assimilation dominated the NH 4 +-N, NO 3 −-N, and NO 2 −-N removal process. • Hetertrophic nitrification pathway of DN3 was revealed: NH 4 + → NH 2 OH → NO → N 2 O → N 2. • N eliminating assays under various conditions showed bacterial potential application. • A candidate for treatment of mariculture wastewater was provided by this work. Recently, the functional microorganisms capable of eliminating nitrogenous waste have been applied in mariculture systems. As a potential candidate for treating mariculture wastewater, strain DN3 eliminated 100% of ammonia and nitrate and 96.61%–100% of nitrite within 72 h, when single nitrogen sources at concentrations of 0–50 mg/L. Strain DN3 also exhibited the efficient removal performance of mixed-form nitrogen (ammonia, nitrate, and nitrite) at salinity 30 ‰, C/N ratio 20, and 180 rpm. The nitrogen assimilation pathway dominated inorganic nitrogen metabolism, with less nitrogen (14.23%-25.02% of TN) lost into the air via nitrification and denitrification, based on nitrogen balance analysis. Moreover, the bacterial nitrification pathway was explored by enzymatic assays and inhibition assays. These complex nitrogen assimilation and dissimilation processes were further revealed by bacterial genome analysis. These results provide important insight into nitrogen metabolism of Halomonas sp. and theoretical support for treating mariculture wastewater with strain DN3. [ABSTRACT FROM AUTHOR]

Producing enough food to simultaneously address food shortage and agro-environmental pollution problems attracts attention globally. To quantify the risks of nutrition crisis to food security and the agro-environment under current agricultural policies in China, this study evaluates and predict the spatiotemporal patterns of nitrogen (N) flows during 1949–2050 through material flow analysis (MFA) and spatial analysis methods. The results show that (1) the crop harvest (including grains, fruits and vegetables) in China increased by a factor of 8.12 from 1949 to 2019, accompanied by a large amount of N loss to the environment. Compared to 1949, N runoff increased 1.23 times in 1979 and 3.43 times in 1999 after which time agricultural pollution control policy achieved initial results, and the crop harvest increased steadily. (2) At the national average level, crop production will increase by 58.60% in 2050, which is higher than the food security threshold while N loss to the environment will be lower than the agro-environmental risk threshold. Under the current agricultural policy, the win-win goals of crop production increase and pollution control can be realized in China. (3) China has obvious temporal and spatial differences in N flows, for which four regions has been divided. Region II, mainly located in Yangtze River Economic Belt, is a high-risk area for N loss. By 2050, environmental pollution can be controlled under the current agricultural policies. However, crop production will only increase by 10% compared with its historical high value, lower than food security threshold. It is necessary to implement more targeted management of high-risk areas by adopting methods such as fallowing or construction of pollution buffer zones while improving N fertilizer use efficiency. For region III, the impact of N loss on the environment has always been at a low level, so there is still great room for increasing future crop production in this region. On average, China will be able to achieve green and sustainable development for agriculture nationally, but there are remaining food security risks in high N loss areas. More targeted N management strategies should be applied to achieve better goals in the future. [Display omitted] • Crop harvest increased by 8.12 times, accompanied by a large amount of N losses. • Compare to 2014, N runoff in 2019 reduced by 15% for the environmental policies. • Win-win goals for food security and pollution control can be reached in 2050. • To achieve better goals, 4 regions are divided to apply more targeted N management strategies. [ABSTRACT FROM AUTHOR]

Recovery of coalbed methane (CBM) is of great significance for environmental protection, safe production of coal mines, and clean energy supply. To reveal the efficiency difference of different nitrogen reverse Brayton cycles (N 2 -RBC) for recovering CBM and identify the most efficient N 2 -RBC in terms of energy consumption and economy, four typical N 2 -RBCs were studied numerically. Each process was optimized globally by performing genetic algorithm (GA) procedure, using specific power consumption (SPC) per unit product as the objective function. Pinch analysis approach was used to improve N 2 -RBC. All proposed processes were assessed comprehensively concerning efficiency, exergy loss, and economy. It is found that the slope of the hot/cold composite curve is greatly influenced by the material streams' mass flow rate while slightly affected by the specific heat except for the region near critical parameters. The parallel arrangement of expanders reaches a better match between hot and cold composite curves than the series. For the liquefaction capacity of 10 tons per day, the liquefaction process using parallel N 2 -RBC achieves the lowest SPC of 0.72 kWh·kg−1 and the highest figure of merit of 31.11%. It also has the lowest exergy loss of 180.1 kW and a total investment of 4047.76 k$, respectively. • Four typical N 2 -RBCs are assessed concerning efficiency, exergy loss, and economy. • Parallel N 2 -RBC is evaluated as the most profitable. • Factors affecting the shape of the composite curve are investigated. • Pinch analysis approach is used to guide improvement of N 2 -RBC for the first time. • Parallel N 2 -RBC achieves more excellent match between composite curves than series. [ABSTRACT FROM AUTHOR]