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Nitrogen and phosphorous support the ecosystem by supplying nutrients to algae and aquatic plants. Having them in excess results in the eutrophication of waters creating quality problems. In the past, nitrogen has been widely investigated for wells in the context of groundwater flow. However, a national-scale nitrogen assessment in rivers and streams has not received enough attention. In this study, the Wilcoxon rank-sum test, a non-parametric hypothesis testing method, has been applied to nitrogen concentration in the form of nitrate-nitrogen and nitrite-nitrogen in rivers and streams of the Contiguous United States. This approach was particularly chosen because of the non-normal and positively skewed nitrogen levels occurring in the surface flow. This method was able to identify the impaired body of waters as well as quantify the confidence, significance, and errors involved. The Northern Appalachians (NAP), Northern Plains (NPL), and Xeric (XER) ecoregions were identified as the ecoregions worsening in the nitrogen-nitrate condition with NAP, and XER needed immediate action. The nitrite-nitrogen condition did not pose an immediate threat, so mitigation efforts should focus more on nitrate-nitrogen remediation. It was shown that the method was superior to the two-sample t-test by yielding lower type II errors. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate the applicability of nitrogen microwave inductively coupled atmospheric pressure mass spectrometry (MICAP-MS) for Ca, Fe, and Se quantification in human serum using isotope dilution (ID) analysis. The matrix tolerance of MICAP-MS in Na matrix was investigated, revealing that high Na levels can suppress the signal intensity. This suppression is likely due to the plasma loading and the space charge effect. Moreover, 40Ca and 44Ca isotopic fractionation was noted at elevated Na concentration. Nine certified serum samples were analyzed using both external calibration and ID analysis. Overestimation of Cr, Zn, As, and Se was found in the results of external calibration, which might result from C-induced polyatomic interference and signal enhancement, respectively. Further investigations performed with methanol showed a similar enhancement effect for Zn, As, and Se, potentially supporting this assumption. The mass concentrations determined with ID analysis show metrological compatibility with the reference values, indicating that MICAP-MS combined with ID analysis can be a promising method for precise Ca, Fe, and Se determination. Moreover, this combination reduces the influence of matrix effects, broadening the applicability of MICAP-MS for samples with complex matrixes. [ABSTRACT FROM AUTHOR]

Nitrogen pollution in water environments has reached critical levels globally, primarily stemming from agricultural runoff, industrial discharges, and untreated sewage. The excessive presence of nitrogen compounds poses a significant threat to water quality, leading to adverse impacts on ecosystems and human health. Reaching a breakthrough in the technology of constructed wetlands (CWs) for mitigating nitrogen pollution is hindered by existing knowledge gaps regarding the mechanisms involved in the removal process. Reaching this understanding, we offer a comprehensive summary of current advancements and theories in this research field. Initially, bibliometric techniques were employed to identify yearly patterns in publications and areas of research focus. Subsequently, the chosen documents underwent statistical analysis using VOSviewer_1.6.20 to determine countries' annual productivity, significant publication years, influential authors, keyword clustering analysis, and more. Finally, a comprehensive overview is provided on the elimination of nitrogen through CWs, encompassing insights into microbial communities and structure types. This analysis aims to uncover potential strategies for optimizing the rate of nitrogen removal. Furthermore, this study elucidates the current research trend concerning the nitrogen removal performance of CWs and identifies challenges and future research directions in this field. [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]

Ammonia, a vital component in the synthesis of fertilizers, plastics, and explosives, is traditionally produced via the energy‐intensive and environmentally detrimental Haber–Bosch process. Given its considerable energy consumption and significant greenhouse gas emissions, there is a growing shift toward electrocatalytic ammonia synthesis as an eco‐friendly alternative. However, developing efficient electrocatalysts capable of achieving high selectivity, Faraday efficiency, and yield under ambient conditions remains a significant challenge. This review delves into the decades‐long research into electrocatalytic ammonia synthesis, highlighting the evolution of fundamental principles, theoretical descriptors, and reaction mechanisms. An in‐depth analysis of the nitrogen reduction reaction (NRR) and nitrate reduction reaction (NitRR) is provided, with a focus on their electrocatalysts. Additionally, the theories behind electrocatalyst design for ammonia synthesis are examined, including the Gibbs free energy approach, Sabatier principle, d‐band center theory, and orbital spin states. The review culminates in a comprehensive overview of the current challenges and prospective future directions in electrocatalyst development for NRR and NitRR, paving the way for more sustainable methods of ammonia production. [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]

This article discusses the absolute chronology of burials from the 3rd and 2nd millennia BC discovered under the mounds of three barrows in the Kordyshiv cemetery in western Ukraine. Its aim is to create a chronological model of the burials by modeling 27 AMS 14C dates obtained from 21 individuals buried in single and collective graves. Dietary analysis of stable carbon (δ13C) and nitrogen (δ15N) isotope values are presented. The Bayesian modeling of the 14C dates from the three Kordyshiv barrows revealed the extremely important role of these monuments as long-term objects used for ritual purposes. At the end of the 3rd millennium BC, the epi-Corded Ware Culture (epi-CWC) community erected a mound over the central burial in Barrow 2, then interred the graves of three additional deceased. After several hundred years Barrow 2 was reused by Komarów Culture (KC) communities from the Middle Bronze Age (MBA) who interred their deceased in the existing mound. The oldest monument with MBA burials was Barrow 3, in which the dead were buried in a two-stage sequence before and after the mid-2nd millennium BC. The youngest dated grave was Burial 1 in Barrow 1, comprising a collective burial that was interred between 1400 and 1200 BC. The additional analyses of carbon and nitrogen isotopes show significant differences in the diet of epi-CWC individuals buried in Barrow 2 from the individuals representing the KC. [ABSTRACT FROM AUTHOR]

Aiming for specific energy improvements, lithium‐ion battery (LIB) research explores Si based materials as potential alternatives for the negative electrode/anode. Si exhibits a high specific capacity when lithiated, accompanied by a large volumetric expansion. To mitigate expansion induced failures, composite materials with finely distributed Si inside a scaffold have been established. Potential scaffolds to create such Si composites are nano porous SiO2 materials, such as MCM‐41. MCM‐41 exhibits a fine nanostructure, and the synthesis allows precise tuning of the pore properties and thus, after filling with Si, of Si morphology and Si content in the composite. In this work, insights into relevant MCM‐41 synthesis parameters are acquired, with special attention towards specific pore volumes and pore sizes of the SiO2 powders. Materials characterization is performed using nitrogen sorption analysis, X‐ray scattering, electron microscopy and thermogravimetric analysis. Selected MCM‐41 scaffolds are processed to Si composites and integrated into LIB electrodes. The specific capacity and the stability of the Si−SiO2 composites are evaluated by PITT and galvanostatic cycling. They show capacities above 800 mAh g−1, i. e. more than twice the specific capacity of industry standard graphite, and last over 200 charge/discharge cycles before their capacity loss exceeds 25 %. [ABSTRACT FROM AUTHOR]

The acceleration of the nitrogen cycle and the nitrogen excess observed in some coastal waters has increased interest into understanding the biochemical and molecular basis of nitrogen metabolism in various microorganisms. To investigate nitrogen metabolism of a novel heterotrophic nitrification and aerobic denitrification bacterium Klebsiella aerogenes strain (B23) under nitrogen-rich conditions, we conducted physiological and transcriptomic high-throughput sequencing analyses on strain B23 cultured on potassium nitrate–free or potassium nitrate–rich media. Overall, K. aerogenes B23 assimilated 82.47% of the nitrate present into cellular nitrogen. Further, 1,195 differentially expressed genes were observed between K. aerogenes B23 cultured on potassium nitrate– free media and those cultured on potassium nitrate-rich media. Gene annotation and metabolic pathway analysis of the transcriptome were performed using a series of bioinformatics tools, including Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Non-Redundant Protein Database annotation. Accordingly, the nitrogen metabolism pathway of K. aerogenes B23 was analyzed; overall, 39 genes were determined to be involved in this pathway. Differential expression analysis of the genes involved in the nitrogen metabolism pathway demonstrated that, compared to the control, FNR, NarK/14945, fdx, gshA, proB, proA, gapA, argH, artQ, artJ, artM, ArgR, GAT1, prmB, pyrG, glnS, and Ca1 were significantly upregulated in the nitrogen-treated K. aerogenes B23; these genes have been established to be involved in the regulation of nitrate, arginine, glutamate, and ammonia assimilation. Further, norV, norR, and narI were also upregulated in nitrogen-treated K. aerogenes B23; these genes are involved in the regulation of NO metabolism. These differential expression results are important for understanding the regulation process of key nitrogen metabolism enzyme genes in K. aerogenes B23. Therefore, this study establishes a solid foundation for further research into the expression regulation patterns of nitrogen metabolism–associated genes in K. aerogenes B23 under nitrogenrich conditions; moreover, this research provides essential insight into how K. aerogenes B23 utilizes nutritional elements. [ABSTRACT FROM AUTHOR]

The assessment of cropland carbon and nitrogen (C and N) balances plays a key role in identifying cost-effective mitigation measures to combat climate change and reduce environmental pollution. In this paper, a biogeochemical modelling approach is adopted to assess all C and N fluxes in a regional cropland ecosystem of Thessaly, Greece. Additionally, the estimation and quantification of the modelling uncertainty in the regional inventory are realized through the propagation of parameter distributions through the model, leading to result distributions for modelling estimations. The model was applied to a regional dataset of approximately 1000 polygons, deploying model initializations and crop rotations for the five major crop cultivations and for a time span of 8 years. The full statistical analysis on modelling results (including the uncertainty ranges given as ± values) yields for the C balance carbon input fluxes into the soil of 12.4 ± 1.4 t C ha -1 yr -1 and output fluxes of 11.9 ± 1.3 t C ha -1 yr -1 , with a resulting average carbon sequestration of 0.5 ± 0.3 t C ha -1 yr -1. The averaged N influx was 212.3 ± 9.1 kg N ha -1 yr -1 , while outfluxes of 198.3 ± 11.2 kg N ha -1 yr -1 were estimated on average. The net N accumulation into the soil nitrogen pools was estimated to be 14.0 ± 2.1 kg N ha -1 yr -1. The N outflux consists of gaseous N fluxes composed of N 2 O emissions of 2.6 ± 0.8 kg N 2 O–N ha -1 yr -1 , NO emissions of 3.2 ± 1.5 kg NO–N ha -1 yr -1 , N 2 emissions of 15.5 ± 7.0 kg N 2 –N ha -1 yr -1 and NH 3 emissions of 34.0 ± 6.7 kg NH 3 –N ha -1 yr -1 , as well as aquatic N fluxes (only nitrate leaching into surface waters) of 14.1 ± 4.5 kg NO 3 –N ha -1 yr -1 and N fluxes of N removed from the fields in yields, straw and feed of 128.8 ± 8.5 kg N ha -1 yr -1. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are porous organic materials with well‐defined and uniform structure. The material is an excellent candidate as a solid adsorbent for iodine adsorption. In the present study, we report the synthesis of COF with porphyrin moiety, TF‐TA‐COF, by solvothermal reaction, which was characterized by XRD, solid‐state 13C NMR, IR, TGA, and nitrogen adsorption‐desorption analysis. TF‐TA‐COF showed a high specific surface area of 443 m2 g−1, and exhibited good adsorption performance for iodine vapor, with an adsorption capacity of 2.74 g g−1. XPS and Raman spectrum indicated that a hybrid of physisorption and chemisorption took place between host COF and iodine molecules. The electric properties of iodine‐loaded TF‐TA‐COF were also studied. After doped with iodine, the conductivity of the material increased by more than 5 orders of magnitude. The photoconductivity of I2‐doped COF was also studied and TF‐TA‐COF showed doping‐enhanced photocurrent generation. [ABSTRACT FROM AUTHOR]

Purpose: Diet-related diseases are advancing as the leading cause of death globally. As self-reporting of diet by patients can be associated with errors, stable isotopes of human tissues can be used to diagnose diseases, understand physiology, and detect change in diet. This study investigates the effect of type and amount of food on the nitrogen and carbon concentration (Nconc and Cconc) and isotopic composition (δ15N and δ13C) in human scalp hair and fingernails. Methods: A total of 100 residents participated in the study whereas only 74 individuals provided complete diet history. Sixty-six food items majorly available to them were also collected. The Nconc, Cconc, δ15N and δ13C values of human hair, nails and food items were determined. Results: The Nconc, Cconc, δ15N and δ13C values between plant-sourced and animal-sourced food items, as well as human hair and nail tissue were significantly different (p < 0.05). The δ15N value of human tissues was distinct between lacto-vegetarians and omnivores by 0.9‰. The δ15N and δ13C values of human tissues increased by 0.4–0.5‰ with every 5% increase in the consumption of animal protein. Conclusions: The study helps to demarcate lacto-vegetarians from omnivores, and estimate the percentage of animal protein in diet based on the dual isotope values of human tissues. It also acts as a reference to determine isotopic composition of hair tissue provided the isotope value of nail tissue is known and vice versa. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is abundant in the atmosphere as N2, which is converted into reactive forms (Nr) for plant assimilation. In pre-industrial times, atmospheric N2 conversion to Nr balanced Nr reconversion to N2, but 20th-century human activity intensified this conversion via synthetic fertilizers, biological N2 fixation, and fossil fuel burning. The surplus of Nr detrimentally impacts ecosystems and human well-being. This study aimed to assess the N use efficiency in the soil–plant system of the soybean-corn succession ( S P S S , C ) in Mato Grosso and Mato Grosso do Sul, Brazil's midwest. We estimated N macrofluxes in S P S S , C and identified key agro-environmental indicators. Between 2008 and 2020, the yearly sowed area for the S P S S , C increased by 3.3-fold (currently 7.3 million ha). The average annual input of net anthropogenic Nr, average annual N balance, and N loss in S P S S , C was estimated to be ~204 kg [N] ha−1, 57 kg [N] ha−1, and 30 kg [N] ha−1, respectively, indicating persistent N accumulation and loss. The average results of the agronomic efficiency and N retention indicator in the S P S S , C was 0.71 and 0.90, respectively. Modest N use efficiency results reflect N loss effects. Despite these limitations, there are opportunities in S P S S , C for management strategies to reduce N loss and enhance efficiency. [ABSTRACT FROM AUTHOR]

Large predators are essential in maintaining ecosystem functioning, and comprehending how their feeding habits change across natural and human-dominated landscapes is crucial to preserve biodiversity. In this study, the diet of Iberian wolves (Canis lupus signatus) during pup rearing season (July to September) has been studied in relation to prey abundance and putting emphasis in the analysis of the differences between zones, wolf groups and individual factors (age, sex and social status). For this, non-invasive monitoring was carried out in three zones of Spain where nine different wolf breeding groups were detected (Galicia, n = 4; Zamora, n = 4 and Valladolid, n = 1). Faecal samples were collected near breeding sites for dietary and genetic analyses, registering if it was or not a scent mark to know the social status of the individuals. Prey availability was determined by camera trapping or requesting the official census of wild prey in the study areas. We found differences in wolf’s diet depending on the zone and the breeding group however, the diet did not vary depending on the age, sex and social status. In general, Iberian wolves mainly fed on wild ungulates (wild boar, roe deer and red deer), feeding on the most abundant prey, except for Baldriz group in Galicia which seems to be specialized in hunting roe deer. Domestic animals’ consumption (sheep, goat, donkey, pig) was not high, but it occurred specially in agriculture and livestock areas (Ferreras in Zamora and Valladolid) where wild prey were less available. Significance statement: In this study, we shed light on the vital role of Iberian wolves in the ecosystem by investigating the dietary preferences during pup rearing season across different landscapes. Our research revealed differences in wolf diets based on geographic location and breeding groups, emphasizing their adaptability. We found that age, sex, and social status did not significantly influence their dietary preferences. Iberian wolves predominantly target wild ungulates, except for a specialized group in Galicia. Our study introduces a novel approach as it is the first to analyse wolf diet based on individual factors and using nitrogen analysis. Additionally, the study highlights previously overlooked dietary patterns of the Iberian wolf subspecies, despite its critical role in the ecosystem as a top predator. Furthermore, we emphasize the necessity of conserving wild ungulate populations to reduce livestock attacks by ensuring a stable supply of wild prey, promoting coexistence between humans and wolves. [ABSTRACT FROM AUTHOR]

As a biological alternative to the antimicrobial action of SO2, bioprotection has been proposed to winemakers as a means to limit or prevent grape musts microbial alteration. Competition for nitrogenous nutrients and for oxygen are often cited as potential explanations for the effectiveness of bioprotection. This study analyses the effect of a bioprotective M. pulcherrima strain on the growth of one H. valbyensis strain and one H. uvarum strain. Bioprotection efficiency was observed only against H. valbyensis inoculated at the two lowest concentrations. These results indicate a potential species-dependent efficiency of the bioprotective strain and a strong impact of the initial ratio between bioprotective and apiculate yeasts. The analysis of the consumption of nitrogen compounds revealed that leucine, isoleucine, lysine and tryptophan were consumed preferentially by all three strains. The weaker assimilation percentages of these amino acids observed in H. valbyensis at 24 h growth suggest competition with M. pulcherrima that could negatively affects the growth of the apiculate yeast in co-cultures. The slowest rate of O2 consumption of H. valbyensis strain, in comparison with M. pulcherrima, was probably not involved in the bioprotective effect. Non-targeted metabolomic analyses of M. pulcherrima and H. valbyensis co-culture indicate that the interaction between both strains particularly impact lysin and tryptophan metabolisms. [ABSTRACT FROM AUTHOR]

The so-called man-eating wolves of Turku, a pack of three wolves, reportedly killed 22 children in South-Western Finland in 1880–1881. Enormous efforts were carried out to eradicate them. In January 1882 the last remaining wolf was killed. Since then, there has been considerable debate regarding the validity and extent of the man-eating behaviour. This study aims to clarify whether man-eating behaviour can be observed from the remains of these wolves. One of the wolves was mounted in 1882 and is on display at St. Olaf's school in Turku, enabling us to collect hair keratin samples. Additionally, hair keratin was collected from two other suspected man-eaters. We analysed carbon (δ13C) and nitrogen (δ15N) stable isotope values to study the wolf's diet during the last months of its life. Samples from seven temporally concurrent wolves were used to construct reference values. Our analyses indicated that δ15N values of suspected man-eaters were relatively low compared to the reference sample. We could not detect clear trends in isotope ratios associated with potential man-eating behavior. We believe that this lack of distinctive patterns can be explained by the relatively minor role that man-eating played in their overall diet. [ABSTRACT FROM AUTHOR]

Background: Mungbean is a versatile legume crop grown in various cropping systems. Despite its adaptability, the yield is hindered by the low yielding capacity of undifferentiated varieties and their limited ability to fix nitrogen. The current study aims to identify stable genotypes through continuous cultivation in eight different environments over two years. Methods: To assess the stability for BNF and seed yield, twenty-five mungbean genotypes were measured at eight diverse agroecological conditions, represented as two different seasons during spring and summer in two consecutive years (2016 and 2017) at two locations - TCA, Dholi, Muzaffarpur and Pusa Farm, RPCAU, Pusa, Samastipur, Bihar. To evaluate the most stable and superior genotypes, three parameters, viz., xi, bi and S²di were calculated. Result: There is a substantial amount of variability across genotypes and environments, as shown by the pooled analysis of variance. The genotype, Pusa 11-31 had shown regression near to unity, comprised with non-significant standard deviation along with higher mean seed yield and biological nitrogen fixation indicates that this is the most stable genotypes for the above traits. [ABSTRACT FROM AUTHOR]

Moderate control of rice tillering and the development of rice varieties with large panicles are important topics for future high-yield rice breeding. Herein, we found that low-tillering rice varieties stopped tillering earlier and had a larger leaf area of the sixth leaf. Notably, at 28 days after sowing, the rice seedlings of the low-tillering group had an average single-culm above-ground biomass of 0.84 g, significantly higher than that of the multi-tillering group by 56.26%, and their NSC (non-structural carbohydrate) and starch contents in sheaths were increased by 43.34% and 97.75%, respectively. These results indicated that the low-tillering group of rice varieties had a stronger ability to store photosynthetic products in the form of starch in their sheaths, which was thus more beneficial for their large panicle development. The results of carbon and nitrogen metabolism analyses showed that the low-tillering group had a relatively strong carbon metabolism activity, which was more favorable for the accumulation of photosynthesis products and the following development of large panicles, while the multi-tillering group showed relatively strong nitrogen metabolism activity, which was more beneficial for the development and formation of new organs, such as tillers. Accordingly, in the low-tillering rice varieties, the up-regulated genes were enriched in the pathways mainly related to the synthesis of carbohydrates, while the down-regulated genes were mainly enriched in the nitrogen metabolism pathways. This study provides new insights into the mechanism of rice tillering regulation and promotes the development of new varieties with ideal plant types. [ABSTRACT FROM AUTHOR]

The analysis of the nitrogen (N) isotopic composition of organic matter bound to fossil biomineral structures (BB‐δ15N) using the oxidation–denitrifier (O–D) method provides a novel tool to study past changes in N cycling processes. Methods: We report a set of methodological improvements to the O–D method, including (a) a method for sealing the reaction vials in which the oxidation of organic N to NO3− takes place, (b) a recipe for bypassing the pH adjustment step before the bacterial conversion of NO3− to N2O, and (c) a method for storing recrystallized dipotassium peroxodisulfate (K2S2O8) under Ar atmosphere. Results: The new sealing method eliminates the occasional contamination and vial breakage that occurred previously while increasing sample throughput. The protocol for bypassing pH adjustment does not affect BB‐δ15N, and it significantly reduces the processing time. Storage of K2S2O8 reagent under Ar atmosphere produces stable oxidation blanks over more than 3.5 years. We report analytical blanks, accuracy, and precision for this methodology from eight users over the course of ~3.5 years of analyses at the Max Planck Institute for Chemistry. Our method produces analytical blanks characterized by low N content (0.30 ± 0.13 nmol N, 1σ, n = 195) and stable δ15N (−2.20 ± 3.13‰, n = 195). The analysis of reference amino acid standards USGS 40 and USGS 65 indicates an overall accuracy of −0.23 ± 0.35‰ (1σ, n = 891). The analysis of in‐house fossil standards gives similar analytical precision (1σ) across a range of BB‐δ15N values and biominerals: zooxanthellate coral standard PO‐1 (6.08 ± 0.21‰, n = 267), azooxanthellate coral standard LO‐1 (10.20 ± 0.28‰, n = 258), foraminifera standard MF‐1 (5.92 ± 0.28‰, n = 243), and tooth enamel AG‐Lox (4.06 ± 0.49‰, n = 78). Conclusions: The methodological improvements significantly increase sample throughput without compromising analytical precision or accuracy down to 1 nmol of N. [ABSTRACT FROM AUTHOR]

Nanostructured scaffolds based on cellulose with advanced performances and personalized morphologies for bone tissue engineering are under technological development. 3D-printing and supercritical carbon dioxide (scCO2) technologies are innovative processing strategies that, when combined, allow the precise fabrication of highly porous aerogel scaffolds. Novel sterile cellulose-in-cellulose aerogels decorated with superparamagnetic iron oxide nanoparticles (SPIONs) are synthesized in this work by an integrated technological platform based on 3D-printing and scCO2. Methylcellulose (MC) and bacterial nanocellulose (BC) are two versatile cellulosic polysaccharides with remarkable physicochemical and biological performances, whereas SPIONs are commonly used to functionalize biomaterials aimed at tissue engineering. Aerogels with hierarchical porosity and high structural resolution were obtained according to nitrogen adsorption–desorption analysis, confocal, scanning and transmission microscopies (SEM and TEM). The magnetic properties of SPIONs-doped aerogels confirmed the correct functionalization of the nanostructures. Finally, NIH/3T3 fibroblast cell viability, hemocompatibility with human blood and safety tests (in ovo with HET-CAM and in vivo with Artemia salina) indicate the biocompatibility of the cellulose-in-cellulose aerogels. [ABSTRACT FROM AUTHOR]

Leaf senescence is an important developmental process for deciduous trees during which part of leaf nitrogen is remobilized to branches, thus being beneficial for nitrogen conservation. However, the associated regulatory mechanism remains largely unknown in deciduous trees. In this study, nitrogen dynamics and transcriptomic activity in senescing leaves were measured during autumnal senescence in hybrid poplar. Both concentrations of leaf total nitrogen (N) and amine compounds were found to decline from the pre-senescence (PRE) to the middle-senescence (MS) stage. Although the total N concentration decreased further from MS to the late-senescence (LS) and leveled off to abscission (ABS) stage, amine compound concentration increased continuously from MS to ABS, suggesting that translocation of amine compounds underperformed production of amine compounds in leaves during this period. L-glutamate, L-glutamine and α-aminoadipic acid were the top three amine compounds accumulated in senescent leaves. RNA-Seq profiling identified thousands of differentially expressed genes (DEGs) with functional association with a metabolic transition towards disassimilation. Many genes encoding amino acid metabolism enzymes and amino acid transporters (AATs) were up-regulated. Comparison of expression trend with leaf N dynamics and phylogenetic analysis identified several PtAATs which exhibited down-regulation from MS to LS stage and putatively limited leaf N remobilization. This study can serve as a primary basis to further elucidate the molecular mechanisms of nitrogen remobilization in poplar senescing leaves. [ABSTRACT FROM AUTHOR]

Litchi downy blight, caused by Peronophythora litchii, is one of the most serious diseases in major litchi-producing regions worldwide. The ankyrin (ANK) repeat is one of the most common protein-protein interaction motifs found in all kingdoms of life proteins. ANK-containing proteins have been demonstrated to regulate various biological processes in animals, plants, and fungi. However, their functions in phytopathogenic oomycetes remain unknown. Here, we identified 284 non-redundant genes that encode ANK-containing proteins in P. litchii and classified them into 11 subfamilies. Among them, PlANK1 was found to be highly up-regulated in oospores and from zoospores to the infection process. Loss of PlANK1 in P. litchii resulted in impaired mycelial growth and cyst germination, accelerated zoospore encystment, and increased sensitivity to hyperosmotic stresses and Congo red. Furthermore, PlANK1 deletion mutants were defective in oospore formation and development. Inoculation assays showed that the absence of PlANK1 severely diminished the pathogen's virulence on litchi leaf and fruit. Through transcriptome analysis and nitrogen source utilization assays, we demonstrated that PlANK1 modulates the pathogen's nitrogen metabolism. Altogether, our findings indicate that PlANK1 is a key regulator of sexual and asexual development, and virulence in P. litchii. [ABSTRACT FROM AUTHOR]

Vanadium (IV) chalcogenide materials are of increasing interest for use in catalysis and energy conversion-related applications. Since no ternary compounds are yet known in the V–Se–Te system, we studied ternary VwSeyTe2−y (w = 1.10, 1.13; y = 0.42, 0.72) phases crystallizing in space group P 3 ¯ m1 (no. 164). Two single-crystal specimens with differing compositions of a solid solution were obtained using the ceramic method. All products were characterized by either single-crystal or powder X-ray diffraction. The lattice parameters increase with rising tellurium content in accordance with the larger ionic radius of the tellurium anion compared to selenium. The chemical compositions were confirmed by energy-dispersive X-ray spectroscopy. Furthermore, magnetic measurements mostly revealed antiferromagnetic properties. Simultaneous differential scanning calorimetry/thermogravimetric analyses in a nitrogen atmosphere showed endothermic decomposition accompanied by the formation of VN. The decomposition of VSe and VTe was observed in an argon atmosphere. The results of this work can serve as a basis for the synthesis of new phases in the V–Se–Te and related vanadium chalcogenide systems. [ABSTRACT FROM AUTHOR]

In this study, the production of two-stage metal-free catalysts from pistachio shells, which are abundant in Turkey and the world, is designed. The first stage of the study includes activated carbon(AC) production, and the second stage includes the production of heteroatom-doped catalysts as a result of hydrothermal heating of the obtained activated carbon with nitric acid. These metal-free catalysts obtained were used for the production of hydrogen (H2) from sodium borohydride (NaBH4) in methanol. In H2 production experiments, the NaBH4 concentration effect, temperature effect and catalyst amount effect and catalyst reusability parameters were investigated. HGR values obtained from the methanolysis using metal-free catalysts treated by the nitric acid/water ratio: 1:2, 1:3, 1:4, 1:5 are 8041, 8955, 10600 and 8333 ml min−1 g−1, respectively. The activation energy (Ea) of the production of H2 from NaBH4(NaBH4–H2–P) in methanol by the metal-free catalyst was 18.19 kJ mol−1. Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), CHNS elemental analysis, scanning electron microscopy (SEM), and nitrogen adsorption analyses were performed for the characterization of the metal-free catalysts obtained. In addition, the mechanism of the obtained metal-free catalysts on the NaBH4–H2–P in methanol is discussed. [ABSTRACT FROM AUTHOR]

The Lower Laguna Madre of Texas (LLM) is a subtropical, hypersaline lagoon dominated by lush seagrass beds and characterized by a historically low freshwater inflow (FWI) regime. From 1998 to 2012, a net 8.8% seagrass decrease occurred in the LLM, primarily Syringodium filiforme and Thalassia testudinum, despite the concomitant expansion of Halodule wrightii. In the middle region of the LLM affected by a major FWI source, the Arroyo Colorado, the decrease was > 20%. We proposed that Thalassia and Syringodium decrease was largely due to high FWI pulses and N loading from an increasingly modified LLM watershed. Salinity modeling studies showed that FWI pulses lowered salinities for months in this region potentially associated with non-point source nutrient (viz. ungauged) inputs. At a site near the Arroyo Colorado, Thalassia biomass and shoot density were lower 319.3 g/m2 and 567 shoots/m2, respectively versus 1296 g/m2 and 3382 shoots/m2 for the most productive LLM site. Targeted sampling in four subwatersheds adjacent to the LLM demonstrated high dissolved N loadings (nitrate and organic nitrogen) to the lagoon. Nitrogen isotope analysis of LLM seagrass further indicated that nitrogen was likely from inland wastewater runoff from the Arroyo Colorado. We concluded that freshwater pulses to the lagoon produce hyposaline conditions and high nutrient loading, stressing seagrasses and resulting in diminished resilience and reduced distribution of Thalassia and Syringodium. With climate change, coastal population growth, and enhanced watershed drainage, episodes of hyposalinity, and enriched nutrient runoff are likely to increase in frequency and duration, altering seagrass resilience and diversity in the LLM. [ABSTRACT FROM AUTHOR]

Adsorption-based atmospheric water harvesting has emerged as a compelling solution in response to growing global water demand. In this context, Metal–organic frameworks (MOFs) have garnered considerable interest due to their unique structure and intrinsic porosity. Here, MOF 801 was synthesized using two different methods: solvothermal and green room temperature synthesis. Comprehensive characterization indicated the formation of MOF-801 with high phase purity, small crystallite size, and excellent thermal stability. Nitrogen adsorption–desorption analysis revealed that green-synthesized MOF-801 possessed an 89% higher specific surface area than its solvothermal-synthesized counterpart. Both adsorbents required activation at a minimum temperature of 90 °C for optimal adsorption performance. Additionally, green-synthesized MOF-801 demonstrated superior adsorption performance compared to solvothermal-synthesized MOF-801, attributed to its small crystal size (around 66 nm), more hydrophilic functional groups, greater specific surface area (691.05 m2/g), and the possibility of having a higher quantity of defects. The maximum water adsorption capacity in green-synthesized MOF-801 was observed at 25 °C and 80% relative humidity, with a value of 41.1 g/100 g, a 12% improvement over the solvothermal-synthesized MOF-801. Remarkably, even at a 30% humidity level, green-synthesized MOF-801 displayed a considerable adsorption capacity of 31.5 g/100 g. Importantly, MOF-801 exhibited long-term effectiveness in multiple adsorption cycles without substantial efficiency decline. [ABSTRACT FROM AUTHOR]

Lanthanum-doped titanium (La/TiO2) nano-photocatalysts were prepared using the sol-gel method and characterized by X-ray diffraction (XRD), zeta potential, and low-temperature nitrogen adsorption analyses. Ester-105, a flotation collector from beneficiation wastewater, was chosen as the target pollutant. The influence of the initial ester-105 concentration, pH, and photocatalyst dosage on the photocatalytic degradation of ester-105 was investigated. To examine the kinetics of the adsorption and photocatalytic degradation of ester-105, a Langmuir adsorption model and Langmuir-Hinshelwood kinetic models were established and discussed. The synthesized photocatalyst comprised anatase-phase TiO2, with an isoelectric point of pH = 6.5, specific surface area of 56.1626m²•g-1, and average pore size of 7.78 nm. The maximum adsorption and the adsorption equilibrium constant of La/TiO2 for ester-105 were determined as 0.338mg²•g-1 and 1.008 L²•g-1, respectively. The first-order kinetic reaction rate constant (k) exhibited a linear relationship with the initial ester-105 concentration. The optimal pH for ester degradation was theoretically determined to be 6.95, and the optimum photocatalyst dosage was found to be 0.2739 g•L-1. Experiments confirmed that the photocatalytic degradation of ester-105 using La/TiO2 followed the Langmuir-Hinshelwood kinetics model, thereby providing a theoretical foundation for the photocatalytic degradation of ester-105 for industrial application. [ABSTRACT FROM AUTHOR]

A newly produced silk fibroin (SF) aerogel particulate system using a supercritical carbon dioxide (scCO2)-assisted drying technology is herein proposed for biomedical applications. Different concentrations of silk fibroin (3%, 5%, and 7% (w/v)) were explored to investigate the potential of this technology to produce size- and porosity-controlled particles. Laser diffraction, helium pycnometry, nitrogen adsorption–desorption analysis and Fourier Transform Infrared with Attenuated Total Reflectance (FTIR-ATR) spectroscopy were performed to characterize the physicochemical properties of the material. The enzymatic degradation profile of the SF aerogel particles was evaluated by immersion in protease XIV solution, and the biological properties by cell viability and cell proliferation assays. The obtained aerogel particles were mesoporous with high and concentration dependent specific surface area (203–326 m2/g). They displayed significant antioxidant activity and sustained degradation in the presence of protease XIV enzyme. The in vitro assessment using human dermal fibroblasts (HDF) confirm the particles' biocompatibility, as well as the enhancement in cell viability and proliferation. [ABSTRACT FROM AUTHOR]

Nitrogen (N) limits crop production, yet more than half of N fertilizer inputs are lost to the environment. Developing maize hybrids with improved N use efficiency can help minimize N losses and in turn reduce adverse ecological, economical, and health consequences. This study aimed to identify single nucleotide polymorphisms (SNPs) associated with agronomic traits (plant height, grain yield, and anthesis to silking interval) under high and low N conditions. A genome-wide association study (GWAS) was conducted using 181 doubled haploid (DH) lines derived from crosses between landraces from the Germplasm Enhancement of Maize (BGEM lines) project and two inbreds, PHB47 and PHZ51. These DH lines were genotyped using 62,077 SNP markers. The same lines from the per se trials were used as parental lines for the testcross field trials. Plant height, anthesis to silking interval, and grain yield were collected from high and low N conditions in three environments for both per se and testcross trials. We used three GWAS models, namely, general linear model (GLM), mixed linear model (MLM), and Fixed and Random model Circulating Probability Unification (FarmCPU) model. We observed significant genetic variation among the DH lines and their derived testcrosses. Interestingly, some testcrosses of exotic introgression lines were superior under high and low N conditions compared to the check hybrid, PHB47/PHZ51. We detected multiple SNPs associated with agronomic traits under high and low N, some of which colocalized with gene models associated with stress response and N metabolism. The BGEM panel is, thus, a promising source of allelic diversity for genes controlling agronomic traits under different N conditions. [ABSTRACT FROM AUTHOR]

A new pilot plant equipment with application of the ammonium fluorine technology for processing silicon-containing raw materials using the physical effects of sublimation and desublimation has been developed and manufactured. It is shown that the usage of the created device for the processing of metallurgical waste makes it possible to separate amorphous silicon dioxide in the form of a dispersed powder from slags, extract iron oxide, and obtain a collective concentrate of valuable components. The synthesized silicas have been studied by inductively coupled plasma (ICP) mass-spectrometry, scanning electron microscopy, X-ray diffraction, small angle X-ray scattering, laser correlation spectroscopy, and low-temperature nitrogen adsorption–desorption analysis. It has been shown that an increase in hexafluorosilicate concentration by 10 times during the silica synthesis led to increasing effective diameter of silica particles more than four times, and a decrease in the SiO2 yield by ~ 25%. The silica samples have amorphous structure and purity ≥ 99.97%. The specific surface area is equal to 58 m2/g for silica synthesized using copper melting slag and SBET = 10 m2/g for silica synthesized from microsilica prepared using ferrosilicon production waste. The total pore volume is 0.22 cm3/g and 0.08 cm3/g for these silica samples, respectively. There is a fraction of pores inaccessible (closed) for nitrogen molecules that can be detected with the SAXS method since there is a relation SSAXS > SBET. Thus, the use of waste from metallurgical industries allows one to implement a resource-saving technology for producing highly disperse silica with appropriate textural characteristics. [ABSTRACT FROM AUTHOR]

NaBi(MoO4)2 mesoporous material was prepared by a simple solvothermal method. Co3O4 and CuO doped NaBi(MoO4)2 composites were prepared by sintering NaBi(MoO4)2 nanoparticles covered with the corresponding nitrate. The NaBi(MoO4)2 and the composites were characterized by XRD, SEM, TEM and nitrogen adsorption–desorption analysis. The results show that NaBi(MoO4)2 was mesoporous structures assembled by random aggregation of nanoparticles with an average grain size of about 31 nm. In the composite, the Co3O4 was obtained and uniformly distributed on the surfaces of NaBi(MoO4)2 nanoparticles to form heterojunctions. The sensor based on pure NaBi(MoO4)2 mesoporous material showed a response value of up to 44.8 for 100 ppm n-butanol at an optimum operating temperature of 260 °C with a fast response and recovery time. The Co3O4-doped NaBi(MoO4)2 composite exhibited superior gas-sensitive properties over the pure NaBi(MoO4)2 mesoporous material. The sensor based on 1.0 wt% Co3O4-doped NaBi(MoO4)2 showed a response value of 63 for 100 ppm n-butanol at 260 °C. [ABSTRACT FROM AUTHOR]

In this article, for the first time, TG-DSC and TG-FTIR investigations of potential pharmaceutics, i.e., analgesic and anticancer active annelated triazinones (1–9) have been presented. The thermal behaviour of these molecules was established in oxidative and inert conditions. The solid–liquid phase transition for each compound (1–9) was documented by one sharp DSC peak confirming the high purity of each sample studied. All the molecules were characterised in terms of calorimetric changes and mass changes during their heating. They revealed high thermal stability in oxidative and inert conditions. The observed tendency in thermal stability changes in relation to a substituent present at the phenyl moiety was found to be similar in air and nitrogen. It was confirmed that annelated triazinones 1–9 were stable up to a temperature range of 241–296 °C in air, and their decomposition process proceeded in two stages under oxidative conditions. In addition, it was established that their thermal stability in air decreased in the following order of R at the phenyl moiety: 4-Cl > 3,4-Cl2 > H > 3-Cl > 4-CH3 > 2-CH3 > 3-CH3 > 2-Cl > 2-OCH3. The volatile decomposition products of the investigated molecules were proposed by comparing the FTIR spectra collected during their thermogravimetric analysis in nitrogen with the spectra from the database of reference compounds. None of annelated triazinones 1–9 underwent any polymorphic transformation during thermal studies. All the compounds proved to be safe for erythrocytes. In turn, molecules 3, 6, and 9 protected red blood cells from oxidative damage, and therefore may be helpful in the prevention of free radical-mediated diseases. [ABSTRACT FROM AUTHOR]

Rationale: Isolation of underivatized amino acids (AAs) using high‐performance liquid chromatography (HPLC) is becoming a popular method for carbon (δ13C) and nitrogen isotope (δ15N) analyses of AAs because of the high analytical precision and for performing dual‐isotope analysis. However, some AAs in natural samples, especially small, hydrophilic AAs, are not suitably separated using reversed‐phase columns (e.g., C18) and ion‐exchange columns (e.g., Primesep A). Methods: We developed a new method for HPLC using a porous graphitic carbon column for the separation of nine hydrophilic AAs. After purification, δ13C and δ15N values of AAs were determined using elemental analyzer/isotope ratio mass spectrometry (EA/IRMS). We demonstrated the application of this method by determining δ13C and δ15N values of individual hydrophilic AAs in a biological sample, the muscle of blue mackerel (Scomber australasicus). Results: Chromatographically, the baseline separation of hydrophilic AAs was achieved in both the standard mixture and the biological sample. We confirmed that δ13C and δ15N values of AA standards remained unchanged during the whole experimental procedure. The δ13C values of AAs in mackerel muscle are also in good agreement with the values obtained using another verified method for δ13C analysis. Conclusions: The good separation performance of hydrophilic AAs and the reliability of δ13C and δ15N analyses of individual AAs using the porous graphite column offer a significant advantage over conventional settings. We suggest that, in the future, the HPLC × EA/IRMS method can be used for reliable δ13C and δ15N analyses of AAs in natural samples. [ABSTRACT FROM AUTHOR]

Simple Summary: Oral squamous cell carcinomas (OSCCs) pose significant therapeutic challenges. Despite the advancement of treatment methods, they are still characterised by a poor prognosis. The isotopic abundance of oral cancers reflects their biology. A better understanding of OSCC biology may improve treatment outcomes. In this study, the isotopic compositions of the nitrogen and carbon of OSCC tissue samples were investigated across different oral cancer localisations. The correlations between the isotopic composition and clinical and histological advancement were established. The results suggest that assessment of the isotopic composition might serve as a valuable tool for determining tumour biology and behaviour. The aim of this paper was to characterise the isotopic composition of oral squamous cell carcinoma (OSCC) specimens of different areas of the oral cavity. Secondly, we assessed whether there was a correlation between clinical stages of OSCC and isotopic abundance. The IRMS procedure was performed on 124 samples derived from 31 patients with OSCC of 15 N and 13 C to assess the isotopic composition. From each individual, four samples from the tumour, two from the margins, and two samples of healthy oral mucous membranes were derived. The two samples from the tumour and two samples from the margin were additionally subjected to histopathological assessment. Then, statistical analysis was conducted. Tumour infiltration tissues of the lower lip were characterised by higher mean δ13C values compared to samples derived from cancers of the other oral cavity regions (−23.82 ± 1.21 vs. −22.67 ± 1.35); (p = 0.04). The mean percentage of nitrogen content in tumour tissues was statistically higher in patients with the most advanced cancers (11.89 ± 0.03%) versus the group of patients with II and III stage cancers (11.12 ± 0.02%); (p = 0.04). In patients at stage IV, the mean δ13C value in the cancer samples equalled −22.69 ± 1.42 and was lower than that in patients at less severe clinical stages (p = 0.04). Lower lip cancer tissues differed in the isotopic abundance of carbon in comparison with tissues derived from the group of combined samples from other locations. Values of δ13C observed in specimens derived from lower lip cancers were similar to those observed in healthy oral mucous membranes. Cancer tissues obtained from patients in the last stage of OSCC had a different isotopic composition in comparison with those obtained from earlier stages. To confirm these observations, further research on larger groups of patients is needed. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoate (PHA) is one of the most promising materials for replacing petroleum-based plastics, and it can be produced from various renewable biomass sources. In this study, PHA production was conducted using Halomonas sp. YLGW01 utilizing mixed volatile fatty acids (VFAs) as carbon sources. The ratio and concentration of carbon and nitrogen sources were optimized through mixture analysis and organic nitrogen source screening, respectively. It was found that the highest cell dry weight (CDW) of 3.15 g/L and PHA production of 1.63 g/L were achieved when the ratio of acetate to lactate in the mixed VFAs was 0.45:0.55. Furthermore, supplementation of organic nitrogen sources such as soytone resulted in a ninefold increase in CDW (reaching 2.32 g/L) and a 22-fold increase in PHA production (reaching 1.60 g/L) compared to using inorganic nitrogen sources. Subsequently, DO-stat, VFAs consumption rate stat, and pH–stat fed-batch methods were applied to investigate and evaluate PHA productivity. The results showed that when pH–stat-based VFAs feeding was employed, a CDW of 7 g/L and PHA production of 5.1 g/L were achieved within 68 h, with a PHA content of 73%. Overall, the pH–stat fed-batch strategy proved to be effective in enhancing PHA production by Halomonas sp. YLGW01 utilizing VFAs. [ABSTRACT FROM AUTHOR]

Particulate organic matter settling out of the euphotic zone is a major sink for atmospheric carbon dioxide and serves as a primary food source to mesopelagic food webs. Degradation of this organic matter encompasses a suite of mechanisms that attenuate flux, including heterotrophic metabolic processes of microbes and metazoans. The relative contributions of microbial and metazoan heterotrophy to flux attenuation, however, have been difficult to determine. We present results of compound specific nitrogen isotope analysis of amino acids of sinking particles from sediment traps and size‐fractionated particles from in situ filtration between the surface and 500 m at Ocean Station Papa, collected during NASA EXPORTS (EXport Processes in the Ocean from RemoTe Sensing). With increasing depth, we observe: (1) that, based on the δ15N values of threonine, fecal pellets dominate the sinking particle flux and that attenuation of downward particle flux occurs largely via disaggregation in the upper mesopelagic; (2) an increasing trophic position of particles in the upper water column, reflecting increasing heterotrophic contributions to the nitrogen pool and the loss of particles via remineralization; and (3) increasing δ15N values of source amino acids in submicron and small (1–6 μm) particles, reflecting microbial particle solubilization. We further employ a Bayesian mixing model to estimate the relative proportions of fecal pellets, phytodetritus, and microbially degraded material in particles and compare these results and our interpretations of flux attenuation mechanisms to other, independent methods used during EXPORTS. [ABSTRACT FROM AUTHOR]

Marine flatfishes have a low metabolic rate and routinely encounter large fluctuations in salinity, and are therefore of interest in the study of diffusive water flux (a proxy for transcellular water permeability), oxygen consumption (ṀO2), ammonia excretion and urea-N excretion as a function of salinity and seawater [Ca2+]. These parameters were measured in two coastal marine flatfishes, Pacific sanddab and Rock sole acclimated to 31 ppt and exposed acutely (for up to 3 h), to environmentally relevant salinities of 45, 15.5, or 7.5 ppt. In both species, diffusive water flux and ammonia excretion rates increased as salinity decreased. ṀO2 and urea-N excretion rates remained relatively unchanged. Nitrogen quotient analysis indicated increased oxidation of protein at lower salinity. A second experimental series was performed on Rock sole to separate the effects of salinity from those of ambient [Ca2+]. In direct contrast to the significant increase seen at 7.5 ppt, reducing salinity from 31 ppt to 7.5 ppt while maintaining [Ca2+] at 10 mM or increasing it to 20 mM resulted in no change in diffusive water flux rate, demonstrating that reduced [Ca2+], rather than reduced salinity itself, is the primary cause for the increases in diffusive water flux. However, ammonia excretion rate increased when salinity was decreased and [Ca2+] was increased compared to 31 ppt with added [Ca2+]. Our results demonstrate that both diffusive water flux and ammonia excretion rates are a function of salinity, that neither are coupled to ṀO2, and that ambient [Ca2+] also plays a role in these rates. [ABSTRACT FROM AUTHOR]

Hawksbill turtles (n = 56) in a foraging ground around Isla San Jose, Gulf of California, Mexico, were caught, measured, and their skin and scutes sampled. Tissue samples from putative prey species were collected from observed hawksbill feeding areas in the foraging ground.Measurements of each turtle's straight carapace length were used to estimate the average life stage of the population. Tissue samples were processed for stable carbon and nitrogen isotope analysis to estimate foraging habits of turtles in this location.The majority (96.4%) of measured individuals' straight carapace length fell in the size range considered to be juveniles.A Bayesian mixing model analysis of the δ13C and δ15N values of hawksbill skin and potential prey indicated that hawksbills consume primarily invertebrates and algae, with lesser contributions from seagrass and mangrove material.There was a positive linear relationship between turtle size and the δ13C values from scute samples, and an increase in the δ13C values of five individuals recaptured in subsequent years suggested a potential location shift from a pelagic habitat in the turtles' post‐hatching, earliest juvenile years to the nearshore foraging area around Isla San Jose in their later juvenile years. [ABSTRACT FROM AUTHOR]

As environmentally friendly materials, cellulose cryogels are good choices due to their biodegradability and ease of use. However, the most crucial issue concerning cellulose cryogels is their weakness in terms of mechanical properties. In this study, two types of Polyamide-Epichlorohydrine resins, named PAE1 and PAE2, and Polyamide-Glutaraldehide-Epichlorohydrine resin (PGE) were synthesized; they were utilized to reinforce cellulose nanofiber gel (CNFG), and this was followed by the freeze-drying process. The density and porosity of the cryogels were improved and evaluated using mathematical equations. The mechanical behavior of the fabricated specimens was examined to obtain the optimized values of processing time and temperature, as well as the resin weight fraction, which yielded the improvement of compressive modulus, yield strength, and the stress at 60% strain (S60) to 2 (MPa), 50 (kPa), and 1.8 (MPa) respectively. Also, attenuated total reflection (ATR) analysis was conducted to study the effect of resins on the cross-linking of cellulose nanofibers (CNF)s; further, nitrogen adsorption–desorption analysis was performed to investigate the specific surface area and mesopore diameter distribution of cryogels using Brunauer–Emmett–Teller (BET) and Barrett-Joyner-Halenda (BJH) methods, respectively. [ABSTRACT FROM AUTHOR]

Zeolites in powder form have the potential to agglomerate, lowering access to active sites. Furthermore, a suspension of fine zeolite powder in liquid media is difficult to separate. Such drawbacks could be improved by dispersing zeolite crystals on support materials. This work demonstrates the dispersion of zeolite NaY crystals on bamboo wood by mixing the wood with zeolite gel before hydrothermal treatment. The syntheses were performed with acid-refluxed and non–refluxed wood. The phase of zeolites, particle distribution and morphology, zeolite content in the wood, and zeolite–wood interaction were investigated using X-ray diffraction, X-ray tomography, scanning electron microscopy, thermogravimetric analysis, nitrogen sorption analysis, and X-ray photoelectron spectroscopy. Higher zeolite content and better particle dispersion were obtained in the synthesis with the acid–refluxed wood. The composite of NaY on the acid-refluxed wood was demonstrated to be an effective adsorbent for Ni(II) ions in aqueous solutions, providing a higher adsorbed amount of Ni(II) per weight of NaY. [ABSTRACT FROM AUTHOR]

Medicago truncatula has been selected as one of the model legume species for gene functional studies. To elucidate the functions of the very large number of genes present in plant genomes, genetic mutant resources are very useful and necessary tools. Fast Neutron (FN) mutagenesis is effective in inducing deletion mutations in genomes of diverse species. Through this method, we have generated a large mutant resource in M. truncatula. This mutant resources have been used to screen for different mutant using a forward genetics methods. We have isolated and identified a large amount of symbiotic nitrogen fixation (SNF) deficiency mutants. Here, we describe the detail procedures that are being used to characterize symbiotic mutants in M. truncatula. In recent years, whole genome sequencing has been used to speed up and scale up the deletion identification in the mutant. Using this method, we have successfully isolated a SNF defective mutant FN007 and identified that it has a large segment deletion on chromosome 3. The causal deletion in the mutant was confirmed by tail PCR amplication and sequencing. Our results illustrate the utility of whole genome sequencing analysis in the characterization of FN induced deletion mutants for gene discovery and functional studies in the M. truncatula. It is expected to improve our understanding of molecular mechanisms underlying symbiotic nitrogen fixation in legume plants to a great extent. [ABSTRACT FROM AUTHOR]

In-home pet food testing has the benefit of yielding data which is directly applicable to the pet population. Validated and standardised in-home test protocols need to be available, and here we investigated key protocol requirements for an in-home canine food digestibility protocol. Participants were recruited via an online survey. After meeting specific inclusion criteria, sixty dogs of various breeds and ages received, during 14 consecutive days, a relatively low and high digestible complete dry extruded food containing titanium (Ti) dioxide. Both foods were given for 7 d in a cross-over design. Owners collected faeces daily allowing daily faecal Ti concentrations and digestibility of nitrogen (N), dry matter (DM), crude ash, organic matter (OM), crude fat (Cfat), starch and gross energy (GE) to be determined. Faecal Ti and digestibility values for all nutrients were not different (P > 0·05) from the second day onwards after first consumption for both foods. One day of faecal collection yielded reliable digestibility values with additional collection days not reducing the confidence interval around the mean. Depending on the accepted margin of error, the food and the nutrient of interest, the minimal required sample size was between 9 and 43 dogs. Variation in digestibility values could in part be explained by a dog's neuter status (N, crude ash) and age (crude ash, Cfat) but not sex and body size. Future studies should focus on further identifying and controlling sources of variation to improve the in-home digestibility protocol and reduce the number of dogs required. [ABSTRACT FROM AUTHOR]

The overapplication of nitrogen to wheat reduces profits and has adverse environmental consequences. Machine learning techniques are employed to identify the factors that hold the most potential in improving nitrogen recommendations. The database used in our analysis consisted of a formula fertilization project, the second soil census of China, and cultivated land fertility evaluation. The results showed that the wheat nitrogen yield response was mainly concentrated around 1300–2400 kg/ha in Henan Province, with the highest values observed in the southern and eastern regions and the lowest in the northern region. The soil nitrogen content, nitrogen fertilizer, wet nitrogen deposition, dry nitrogen deposition, and soil nitrogen supply capacity were mainly concentrated around 0.65–1.30 g/kg, 173–203 kg N/ha, 15–39 kg N/(ha yr), 7–49 kg N/(ha yr), and 105–150 kg N/ha, respectively. When comparing the spatial distribution of the soil nitrogen content, nitrogen fertilizer, and nitrogen deposition, we found that the soil nitrogen supply capacity emerged as the predominant factor controlling wheat grain production. Soil types, precipitation, and temperature demonstrated a notable positive correlation with the soil nitrogen supply capacity. Given this background, it would be unreasonable to rely solely on the soil nitrogen content as the standard for fertilizer management. Particularly in high-yield fields, our focus should be on preserving optimal soil fertility by placing greater emphasis on the soil nitrogen supply capacity rather than simply reducing fertilizer application during wheat growth. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies indicated that air pollution plausibly increases the risk of adverse outcomes in inflammatory bowel disease (IBD) via proinflammatory mechanisms. However, there is scant epidemiological data and insufficient prospective evidence assessing associations between ambient air pollution and clinical outcomes of IBD. OBJECTIVES: We aimed to investigate the associations between ambient air pollution and clinical outcomes among individuals with IBD. METHODS: Leveraging data from the UK Biobank, we included 4,708 individuals with IBD recruited in the period 2006-2010 in this study. A land use regression model was used to assess annual mean concentrations of ambient air pollutants nitrogen including oxides (NOx), nitrogen dioxide (NO2), and particulate matter (PM) with aerodynamic diameter ≤10 μm (PM10) and PM with aerodynamic diameter ≤ 2.5 μm (PM2.5). Individuals with IBD were followed up for incident clinical outcomes of enterotomy, gastrointestinal cancer, and all-cause mortality, ascertained via death registry, inpatient, primary care, and cancer registry data. Cox proportional hazard model was used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for the magnitude of the associations. RESULTS: During a mean follow-up of 12.0 y, 265 enterotomy events, 124 incident gastrointestinal cancer, and 420 death events were documented among individuals with IBD. We found that each interquartile range (IQR) increase in exposure to PM2.5 was associated with increased risk of enterotomy (HR = 1.16; 95% CI: 1.00, 1.34, 푝 = 0.043), whereas an IQR increase in exposure to NOx (HR = 1.10; 95% CI: 1.01, 1.20, 푝 = 0.016), NO2 (HR = 1.16; 95% CI: 1.03, 1.29, 푝 = 0.010), PM10 (HR =1.15; 95% CI: 1.03, 1.30, 푝 = 0.015), and PM2.5(HR=1.14; 95% CI: 1.02, 1.28, 푝 = 0.019) was associated with increased risk of all-cause mortality among individuals with IBD. We did not observe any significant associations between air pollutants and gastrointestinal cancer in the primary analyses. Consistent results were observed in subgroup and sensitivity analyses. CONCLUSIONS: Ambient pollution exposure was associated with an increased risk of enterotomy and all-cause mortality among individuals with IBD, highlighting the important role of environmental health in improving the prognosis of IBD. [ABSTRACT FROM AUTHOR]

BACKGROUND: The distribution of nitrogen isotopes has important significance in paleoclimate, paleosedimentary and evolutionary characteristics. Nitrogen is one of the important heteroatomic elements in crude oil. The nitrogen content of crude oil is generally 0.1% to 2%, mainly in the non-hydrocarbon and asphaltene fractions, and can be divided into basic and non-basic nitrogenous fractions according to polarity. Due to the high carbon/nitrogen ratio of crude oils, accurate nitrogen isotope analysis results cannot be obtained from direct testing for most crude oils. As a result, the research on nitrogen isotopes in crude oil has been developed slowly, and the available data are few, while not being well applied in practice. OBJECTIVES: To determine the nitrogen isotopic distribution characteristics of different nitrogen-containing components in crude oil, and to address the problem of low nitrogen content in crude oil, which makes the direct determination of nitrogen isotopes less stable and reproducible. METHODS: A two-stage separation pre-treatment method was utilized to successively separate the nonhydrocarbon and asphaltene fractions of crude oil, and the basic and neutral nitrogen fractions were separated from the non-hydrocarbon fraction. The characteristics of nitrogen isotope distribution in different nitrogenous components of crude oil were determined by the Dumas combustion method. Multiple stable nitrogen isotope standards (USGS61, USGS62, USGS63) were selected for quality control of nitrogen isotope results. RESULTS: The nitrogen isotope data obtained by this method for each component of crude oil were of good quality, with the uncertainties less than ±0.4‰. By separating and measuring crude oil samples from marine and continental sedimentary environments, the results showed that the nitrogen isotope of crude oil samples in continental sedimentary environment was heavier than that in a marine sedimentary environment. The distribution of nitrogen isotopes of asphaltene fractions was heavier than that of non-hydrocarbon fractions. The distribution characteristics of the nitrogen isotopes of the different polar nitrogen-containing compounds also differed significantly. CONCLUSIONS: The technical dilemma that crude oil samples cannot accurately produce stable nitrogen isotopes due to the disparity in carbon to nitrogen ratios is solved and technical support for the practical application of a crude oil nitrogen isotope index is also obtained. [ABSTRACT FROM AUTHOR]

Four of the crosslinked sodium alginate and polyacrylic acid biopolymers based nanoscale metal natural polysaccharides, [M(AG-PAA)Cl(H2O)3], where M = Co(II), Cu(II), Mn(II) and Ni(II), AG = sodium alginate and PAA = polyacrylic acid, have been synthesized and structurally characterized. Because of their numerous biological and pharmacological activities of polysaccharides, including antimicrobial, immunomodulatory, antitumor, antidiabetic, antiviral, antioxidant, hypoglycemic and anticoagulant activities, polysaccharides are one of the near-promising candidates in the biomedical and pharmaceutical fields. The complexity of the polymeric compounds has been verified by carbon and nitrogen analysis, magnetic and conductance measurements, FT-IR spectra, electronic spectral analysis and thermal analysis (DTA, TG). All the synthesized complexes were non-electrolytes with magnetic moments ranging from 1.74 to 5.94 BM. The polymeric complexes were found to be of octahedral geometry. The developed coordination polymeric was found to be crystalline using X-ray powder diffraction examinations, which is confirmed by the SEM analysis. As a result, the crystallite size of all polymeric nanocrystals was in the range of 14 - 69 nm. The test of four compounds exhibits a broad spectrum of antimicrobial activity against both Gram-positive and Gram-negative bacteria and fungal Candida albicans. Using DPPH as a substrate, studies on radical scavenging tests are carried out. The findings demonstrated the antioxidant activities of each complex. In addition, results showed that the two chosen polymeric complexes had a good ability to kill cancer cells in a dose-dependent way. The copper(II) polymeric complex showed to its superior functionality as evidenced by microbial activity. After 72 h of interaction with the normal human breast epithelial cells (MCF10A), the synthesized polymeric compounds of Cu(II) and Co(II) showed exceptional cytocompatibility with the different applied doses. Compared to poly-AG/PAA/Co(II), poly-AG/PAA/Cu(II) exhibits a greater anticancer potential at various polymeric dosages. [ABSTRACT FROM AUTHOR]

This study aims to determine patterns of isotope discrimination between diet and blood and feathers in the common coot (Fulica atra) in Lake Tonga, North-eastern Algeria, the first time in Algeria on the aquatic avifauna. For this purpose, we investigate the trophic position of the species looking for the seasonal variations in the diet. The stable isotope analysis of nitrogen and carbon was carried out to provide a comprehensive evaluation of the feeding ecology. After plotting the isotopic composition of all potential food sources in the mixing plot, consumed by the coat, whether it is on feathers or blood, the results revealed that the main source of the coot diet in all seasons is Najas pectinata, followed by Gambusia affinis. Whereas, for Nymphaea alba a stable contribution was recorded during both seasons (breeding and reproduction). The food selection of a species is predetermined by its ability to exploit its trophic space, on one hand, and specific nutritional requirements are also essential to various biological functions of the species concerned. [ABSTRACT FROM AUTHOR]

Aiming at analyzing the contribution of every part of vegetation concrete system degrading ammonia nitrogen and exploring the nitrogen migration characteristics during denitrification process, 15NH4Cl tracer was used and added to six airtight glass containers in this study. Samples of concrete aggregate, Bahia grass (Paspalum notatum Flüggé), water and air were acquired on the 1std and 8thd. The results showed that the 15N Atom % of air samples had no obvious change. 15N tracer in each kind of samples taking up the percent of the initial dosing quantity were respectively, on the 1std: Bahia grass 3.8%~6.6%, aggregate 11.9%~17.2%, water 2.9%~80.5%, loss 3.3%~3.8%; on the 8thd: Bahia grass 65.3%~68.7%, aggregate 25.6%~26.2%, water 4.6%~4.8%, loss 0.8%~3.9%. Variance of the 15N abundance of each kind of samples indicate that 15NH4Cl tracer added in the culture solution was mainly absorbed by aggregate at early phase (1 d), while by plant assimilation at later phase (8 d). [ABSTRACT FROM AUTHOR]

Rice is an important target to improve crop nitrogen (N) use efficiency (NUE), and the identification and shortlisting of the candidate genes are still in progress. We analyzed data from 16 published N-responsive transcriptomes/microarrays to identify, eight datasets that contained the maximum number of 3020 common genes, referred to as N-responsive genes. These include different classes of transcription factors, transporters, miRNA targets, kinases and events of posttranslational modifications. A Weighted gene co-expression network analysis (WGCNA) with all the 3020 N-responsive genes revealed 15 co-expression modules and their annotated biological roles. Protein-protein interaction network analysis of the main module revealed the hub genes and their functional annotation revealed their involvement in the ubiquitin process. Further, the occurrences of G-quadruplex sequences were examined, which are known to play important roles in epigenetic regulation but are hitherto unknown in N-response/NUE. Out of the 3020 N-responsive genes studied, 2298 contained G-quadruplex sequences. We compared these N-responsive genes containing Gquadruplex sequences with the 3601 genes we previously identified as NUErelated (for being both N-responsive and yield-associated). This analysis revealed 389 (17%) NUE-related genes containing G-quadruplex sequences. These genes may be involved in the epigenetic regulation of NUE, while the rest of the 83% (1811) genes may regulate NUE through genetic mechanisms and/or other epigenetic means besides G-quadruplexes. A few potentially important genes/processes identified as associated with NUE were experimentally validated in a pair of rice genotypes contrasting for NUE. The results from the WGCNA and G4 sequence analysis of N-responsive genes helped identify and shortlist six genes as candidates to improve NUE. Further, the hitherto unavailable segregation of genetic and epigenetic gene targets could aid in informed interventions through genetic and epigenetic means of crop improvement. [ABSTRACT FROM AUTHOR]

The present study aimed at utilizing technically hydrolyzed lignin (THL), industrial biomass residue, derived in high-temperature diluted sulfuric acid hydrolysis of softwood and hardwood chips to sugars. The THL was carbonized in a horizontal tube furnace at atmospheric pressure, in inert atmosphere and at three different temperatures (500, 600, and 700 °C). Biochar chemical composition was investigated along with its HHV, thermal stability (thermogravimetric analysis), and textural properties. Surface area and pore volume were measured with nitrogen physisorption analysis often named upon Brunauer–Emmett–Teller (BET). Increasing the carbonization temperature reduced volatile organic compounds (40 ÷ 96 wt. %), increased fixed carbon (2.11 to 3.68 times the wt. % of fixed carbon in THL), ash, and C-content. Moreover, H and O were reduced, while N- and S-content were below the detection limit. This suggested biochar application as solid biofuel. The biochar Fourier-transform infrared (FTIR) spectra revealed that the functional groups were gradually lost, thus forming materials having merely polycyclic aromatic structures and high condensation rate. The biochar obtained at 600 and 700 °C proved having properties typical for microporous adsorbents, suitable for selective adsorption purposes. Based on the latest observations, another biochar application was proposed—as a catalyst. [ABSTRACT FROM AUTHOR]