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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]

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]

The study focused on litter processing efficiency of the sesarmid crab, Parasesarma plicatum under experimental conditions and its possible role in carbon structuring in the mangrove habitats. The feeding experiment of crab with different stages of leaves of diverse mangrove species revealed that senescent brown leaves were preferred the most, due to their lesser tannin content. The leaf consumption differed significantly with leaf state as well as mangrove species and highest was for Avicennia officinalis brown leaves. The ingestion-egestion assay of P. plicatum revealed that it assimilated an average of 65.75 ± 10.30% of mangrove litter. The experimental study also revealed that rather than already reported C/N ratio, the inhibiting factors such as tannin and lignin like substances control the palatability of leaves by the crab species. The analysis of carbon and nitrogen variants in the experimental water indicated that handling of leaves by the crab helps in leaching of nutrients to the substratum. Therefore, the findings of litter processing efficiency of this sesarmid crab from the present study highlights its significance in structuring the carbon in natural mangrove habitat. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the changes in food consumption patterns throughout the lives of five individuals (n=5), one subadult and four adults, found in archaeological sites of El Remate, Bajo los Cardones and Finca Cruz. All of them are associated with the Formative period (ca. 2500 - 1000 years B. P.) and are located in the Quebrada de Amaicha (Tucumán, Argentina). We propose an analysis of the carbon and nitrogen isotopic composition in the dentin of different sections of the same tooth and in different teeth of the five individuals. This approach sheds light on the way in which the characteristics of children's diets affect their adulthood, as well as providing a more inclusive perspective on consumption patterns in the agropastoralist societies of the study area by integrating young individuals into the analysis. Little intravariation and intervariation was found, with a predominance of food resources framed in the C4 photosynthetic pattern. The exception is an individual, probably female, whose diet was based on C3 resources during the first period of life. This could be the result of the existence of a "childhood diet" or of a change in geographic residence, with both areas being isotopically distinguishable. Finally, we illustrate the methodological steps required to reconstruct life histories through the serial study of human dental pieces. This is a novel approach, which has been applied to human remains from the Argentine Northwest for the first time. [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]

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]

For the first time, a direct non‐local thermodynamic equilibrium (NLTE) analysis of carbon and nitrogen lines in the spectra of nine RR Lyrae stars was carried out. We have determined the abundances of these elements together with oxygen, and have shown that the nitrogen content is increased in metallicity‐deficient program stars. We conclude that this is a sign of the first dredge up, which occurred at the previous stage of the red giant branch, and brought material processed in an incomplete carbon, nitrogen, oxygen (CNO) cycle to the surface of the star. This effect is significantly enhanced by thermohaline (extra‐) mixing, which is more effective for metal‐poor RR Lyrae stars. This is clearly seen in the plot showing that C/N ration in our sample of stars gradually decreases as metallicity decreases from about −0.2 to −2. Oxygen abundance depends on metallicity in a similar way to what we see in the Population II stars. [ABSTRACT FROM AUTHOR]

Rationale: The stable isotope analysis of carbon and nitrogen is a powerful tool in many ecological studies, but different sample treatments may affect stable isotope ratios and hamper comparisons among studies. The goal of this study was to determine whether treatments that are commonly used to prepare scleractinian coral samples for stable isotope analysis yield different δ15N and δ13C values, and to provide guidelines toward a standardised protocol. Methods: The animal tissues and Symbiodiniaceae of two symbiotic scleractinian coral species (Stylophora pistillata and Porites lutea) were divided into subsamples to test the effects of the drying method, lipid extraction, acidification treatment and water washing. All the subsamples were analysed for their δ15N and δ13C values, using continuous flow elemental analyser/isotope ratio mass spectrometry. Results: The drying method and lipid extraction treatment had no substantial effects on the δ15N and δ13C values of Symbiodiniaceae and animal tissues. Acid treatment did cause significant differences in δ13C values (mean differences ≤0.5‰, with individual samples becoming up to 2.0‰ more negative), whereas no ecologically significant differences were observed in δ15N values. Animal tissue δ13C values may vary depending on whether samples are washed or not. Conclusions: To move towards a standardised protocol in coral research, we recommend using an available drying method (as they are equally acceptable) for the stable isotope analysis of scleractinian corals, examining the need for lipid extraction on a case‐by‐case basis, performing a direct acidification of Symbiodiniaceae and animal tissues, and avoiding washing animal tissue with distilled water. [ABSTRACT FROM AUTHOR]

The Galápagos Penguin Spheniscus mendiculus, Flightless Cormorant Phalacrocorax harrisi, and Waved Albatross Phoebastria irrorata are endemic to Islas Galápagos. They are known to feed on different prey (including crustaceans, cephalopods, and/or several species of epipelagic and benthic fish), in accordance with different foraging strategies. In this work, we used stable-isotope analysis of carbon and nitrogen to corroborate available information on habitat use (δ13C) and trophic position (δ15N). Feather samples from the three species were collected in six different areas prior to the 2011 and 2012 breeding seasons. Results showed differences in foraging strategies between Galápagos Penguins and the other two species (δ13C and δ15N, P < 0.01). The Flightless Cormorant and Waved Albatross showed similar proportions of δ13C (P = 0.07), but they occupied different trophic levels (δ15N, P < 0.01). Isotopic signatures in Galápagos Penguins reflected differences based on their breeding areas (δ13C and δ15N, P < 0.01), which were subject to different environmental conditions. This information could be used to evaluate future ecological conditions among the feeding areas of these species. [ABSTRACT FROM AUTHOR]

Carbon‐and‐oxygen‐doped AlN specimens were prepared by combustion synthesis using Al, graphite, and AlN. Graphite addition changed the product color from white to blue. By XRD, the lattice constant increased slightly with increasing carbon content. Blue AlN powder was synthesized with a molar ratio of the diluent AlN of 0.2‐0.5 with a fixed graphite content of 0.05. At an AlN molar ratio exceeding 0.6, carbon was not successfully incorporated due to the lower reaction temperature. Calcination at 800°C in air removed residual graphite without changing the crystal structure or product color. Oxygen, nitrogen, and carbon analyses revealed that blue AlN powders contained 0.45‐0.54 mass% carbon and 1.4‐1.6 mass% oxygen, while the undoped AlN contained 0.021 mass% carbon and 0.94 mass% oxygen. The origin of the white‐to‐blue color change was investigated via reflection measurements. Blue AlN exhibits an absorption peak at 634 nm (1.96 eV). From first‐principles electronic structure calculations, the C‐doped AlN and carbon‐and‐oxygen‐doped AlN with a 1:1 ratio could be classified as p‐type, whereas the O‐doped AlN and 1:3 carbon‐and‐oxygen‐doped AlN were n‐type. One reason for the absorption peak at 634 nm may be a transition from the conduction band to an upper unoccupied state. These results suggest the possible control of optical and electronic properties of AlN via carbon‐and‐oxygen doping. [ABSTRACT FROM AUTHOR]

Highlights • Adding fertilizers had no adverse effects on the compost fermentation process. • Organic-inorganic aerobic co-composting increased compost nutrients contents. • Adding biochar contributed to the decomposition of stubborn carbonaceous matter. • Biochar improved nitrogen transformation and reduced nitrogen loss. • The 10–15% addition dose of biochar by weight is optimum in this study. Abstract In this article, the changes in carbon, nitrogen components, and humic substances during organic-inorganic aerobic co-composting, with adding biochar as an additive or not, were studied. Results showed that adding a certain amount of inorganic fertilizers had no adverse effects on the compost fermentation process. Biochar enhanced the temperature, pH, oxygen content in the compost piles and ultimately hastened the fermentation process. Biochar contributed to the decomposition of hemicellulose, cellulose, lignin and promoted compost humification. Adding biochar increased the contents of acid hydrolysis nitrogen, amino acid nitrogen, amino sugar nitrogen, unidentified organic nitrogen and decreased the content of ammonia organic nitrogen thus improved nitrogen transformation and reduced nitrogen loss. The addition of biochar increased the nutrients contents in mature composts. The amendment of 10–15% biochar by weight as an additive would be optimum for the co-composting of organic-inorganic materials. These results contributed to produce value-added composting fertilizers. [ABSTRACT FROM AUTHOR]

Decomposing vertebrate cadavers release large, localized inputs of nutrients. These temporally limited resource patches affect nutrient cycling and soil organisms. The impact of decomposing cadavers on soil chemistry is relevant to soil biology, as a natural disturbance, and forensic science, to estimate the postmortem interval. However, cadaver impacts on soils are rarely studied, making it difficult to identify common patterns. We investigated the effects of decomposing pig cadavers (Sus scrofa domesticus) on soil chemistry (pH, ammonium, nitrate, nitrogen, phosphorous, potassium and carbon) over a one-year period in a spruce-dominant forest. Four treatments were applied, each with five replicates: two treatments including pig cadavers (placed on the ground and hung one metre above ground) and two controls (bare soil and bags filled with soil placed on the ground i.e. "fake pig" treatment). In the first two months (15-59 days after the start of the experiment), cadavers caused significant increases of ammonium, nitrogen, phosphorous and potassium (p<0.05) whereas nitrate significantly increased towards the end of the study (263-367 days; p<0.05). Soil pH increased significantly at first and then decreased significantly at the end of the experiment. After one year, some markers returned to basal levels (i.e. not significantly different from control plots), whereas others were still significantly different. Based on these response patterns and in comparison with previous studies, we define three categories of chemical markers that may have the potential to date the time since death: early peak markers (EPM), late peak markers (LPM) and late decrease markers (LDM). The marker categories will enhance our understanding of soil processes and can be highly useful when changes in soil chemistry are related to changes in the composition of soil organism communities. For actual casework further studies and more data are necessary to refine the marker categories along a more precise timeline and to develop a method that can be used in court. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we examined the impact of temperature on the carbon and nitrogen trophic transfers from a macroalga to a macro‐grazer by the use of dual 13C‐ and 15N‐labeling. Using an experimental approach in mesocosms, individuals of the urchin Psammechinus miliaris were maintained for 1 month at 17°C (mean summer temperature in the Bay of Brest) and at 20°C (maximum summer temperature) and fed with 13C‐ and 15N‐labeled Solieria chordalis. The results showed that the urchins’ 13C uptake was 0.30 µg13C g dry weight (DW)−1 at 17°C and 0.14 µg13C g DW−1 at 20°C at the end of the experiment. The lower uptake at the higher temperature may be attributed to a decrease in metabolic activity at 20°C, involving lower feeding and/or respiration rates. Conversely, no significant effect of temperature was detected on 15N uptake. At the end of the experiment, the urchins’ 15N uptake was 0.04 µg15N g DW−1 at 17°C and 0.03 µg15N g DW−1 at 20°C. This suggests that temperature may affect carbon and nitrogen trophic fluxes differently. The use of dual isotope labeling offers interesting prospects and needs to be further extended in order to better understand trophic interactions in marine communities and the consequences of current environmental changes, such as global warming. [ABSTRACT FROM AUTHOR]

Abstract: The environmentally friendly synthesis of highly active Fe‐N‐C electrocatalysts for proton‐exchange membrane fuel cells (PEMFCs) is desirable but remains challenging. A simple and scalable method is presented to fabricate FeII‐doped ZIF‐8, which can be further pyrolyzed into Fe‐N‐C with 3 wt % of Fe exclusively in Fe‐N4 active moieties. Significantly, this Fe‐N‐C derived acidic PEMFC exhibits an unprecedented current density of 1.65 A cm−2 at 0.6 V and the highest power density of 1.14 W cm−2 compared with previously reported NPMCs. The excellent PEMFC performance can be attributed to the densely and atomically dispersed Fe‐N4 active moieties on the small and uniform catalyst nanoparticles. [ABSTRACT FROM AUTHOR]

Precipitation behavior and tensile properties have been investigated for 15Cr-15Mn-4Ni austenitic steels containing 0.2 wt% carbon and/or 0.2 wt% nitrogen. During aging at 600–1000 °C, precipitates such as σ, M 23 C 6 , and Cr 2 N were formed and time-temperature-precipitation diagrams were constructed. The type, size, and density of precipitates depended on the carbon and nitrogen contents. The nitrogen addition suppressed carbide formation while the effect of carbon addition on nitride precipitation was comparatively small. The evolution of tensile properties after aging is explained by the changes in solid solution strengthening and deformation modes caused by the precipitation. The precipitation of M 23 C 6 slightly decreased yield strength and elongation while it increased ultimate tensile strength. On the other hand, the precipitation of Cr 2 N hardly affected tensile properties due to its low volume fraction. [ABSTRACT FROM AUTHOR]

Herein, the multiporous MnO/N-doped carbon (MnO/NC) composite based on the abundant and inexpensive electrolytic manganese dioxide were fabricated through a facile microwave-assisted carbonthermal reduction, combined with a subsequent in-situ polymerization of polydopamine onto MnO along with thermal treatment. As an anode material, it retains a reversible capacity of 770.5 mAh g −1 at 300 mA g −1 and high Coulombic efficiency of 99% over 500 cycles, superior than those values of the pure multiporous MnO alone. The impressive performance is attributed to the splendid structure stability contributed by well-connected three-dimensional porous configuration and the enhanced reaction kinetics as well as electrical conductivity incurred by N-doped carbon layer with multiple type nitrogen. [ABSTRACT FROM AUTHOR]

Soil samples from the Forensic Anthropology Research Facility (FARF) at Texas State University, San Marcos, TX, were analyzed for multiple soil characteristics from cadaver decomposition islands to a depth of 5centimeters (cm) from 63 human decomposition sites, as well as depths up to 15cm in a subset of 11 of the cadaver decomposition islands plus control soils. Postmortem interval (PMI) of the cadaver decomposition islands ranged from 6 to 1752 days. Some soil chemistry, including nitrate-N (NO3-N), ammonium-N (NH4-N), and dissolved inorganic carbon (DIC), peaked at early PMI values and their concentrations at 0-5cm returned to near control values over time likely due to translocation down the soil profile. Other soil chemistry, including dissolved organic carbon (DOC), dissolved organic nitrogen (DON), orthophosphate-P (PO4-P), sodium (Na+), and potassium (K+), remained higher than the control soil up to a PMI of 1752days postmortem. The body mass index (BMI) of the cadaver appeared to have some effect on the cadaver decomposition island chemistry. To estimate PMI using soil chemistry, backward, stepwise multiple regression analysis was used with PMI as the dependent variable and soil chemistry, body mass index (BMI) and physical soil characteristics such as saturated hydraulic conductivity as independent variables. Measures of soil parameters derived from predator and microbial mediated decomposition of human remains shows promise in estimating PMI to within 365days for a period up to nearly five years. This persistent change in soil chemistry extends the ability to estimate PMI beyond the traditionally utilized methods of entomology and taphonomy in support of medical-legal investigations, humanitarian recovery efforts, and criminal and civil cases. [ABSTRACT FROM AUTHOR]

This study cultivated denitrifying granular sludge in three UASB reactors by the semi-starvation fluctuation C/N ratio strategy (reactor 1 (R1): constant C/N ratio; R2: regular fluctuation C/N ratio; and R3: semi-starvation fluctuation C/N ratio (SSF)). Microbial aggregates appeared in R1, R2 and R3 on days 28, 14 and 6, respectively. Compared with the results in R1 and R2, the guanosine tetraphosphate (ppGpp) concentration was highest, the acyl homoserine lactones (AHLs) concentration quickly reached a certain threshold, and more protein (PN) of extracellular polymeric substances (EPS) secretion resulted in the rapid formation of denitrifying granular sludge in R3. The SSF strategy enhances microbial diversity, and denitrifying granular sludge has a better nitrogen removal performance. The result demonstrates that ppGpp, AHLs, EPS and the denitrifying sludge granulation process are associated. A mechanism for denitrifying sludge granulation with SSF strategy was proposed from the aspect of quorum sensing (QS). [ABSTRACT FROM AUTHOR]

Parts of the Fe-C-N system were studied in experiments at 7.8 GPa and 1350°C. It was shown that the admixture of nitrogen extends considerably the domain of melt stability in the system at temperatures close to the Fe-FeC eutectic temperatures. Nitrogen solubility in cementite in equilibrium with the nitrogen- rich melt is below the detection limit of the EMPA technique applied. The metal melt is the only nitrogen concentrator (up to 4 wt % of N) in the range of compositions considered. The data obtained permit the conclusion that, in the case of complete dissolution of carbon and nitrogen, which might occur in the enriched mantle, native iron at ~250 km depth should either be completely molten or consist of a melt and carbide of iron. [ABSTRACT FROM AUTHOR]

In the present study, a relationship is proposed that is capable of predicting the output of the plate dent test. It is shown that the initial density; condensed phase heat of formation; the number of carbon (C), nitrogen (N), oxygen (O); and the composition molecular weight (MW) are the most important parameters needed in order to accurately predict the absolute dent depthproduced on 1018 cold-rolled steel by a detonating organic explosive. The estimatedvalues can be used to predict the detonation pressure (P) of high explosives; furthermore, we show that a correlation exists betweenand the Gurney velocityparameter. The new correlation is used to accurately estimatefor several C-H-N-O explosive compositions. [ABSTRACT FROM PUBLISHER]

We report an eco-friendly strategy for fabrication of nitrogen-doped carbon nanodots (N-CDs) and demonstrate their applications for multicolor cell imaging, patterning, and biosensing. N-CDs have been synthesized using wool as raw material via pyrolysis and microwave treatment, providing a green way for the production of N-CDs without the use of toxic/expensive solvents and starting materials. The prepared N-CDs exhibit exceptional advantages including high fluorescent quantum yield (22.5%), excellent biocompatibility, low toxicity, and satisfactory chemical stability. Depending on these superior properties, the N-CDs have been applied in multicolor bioimaging, patterning, and biosensing. Imaging of living cells has been observed with high resolution using N-CDs as a probe, which validates their use in imaging applications and their multicolor property in the living cell system. Additionally, the obtained N-CDs have been used as fluorescent inks for drawing luminescent patterns, showing favorable application in anti-counterfeit and optoelectronic dimensions. Most strikingly, the as-prepared N-CDs could visualize Fe 3+ fluctuations in living cells with negligible autofluorescence based on their high sensitivity and selectivity detection for Fe 3+ ions with a linear range of 0.1–10 μM and a detection limit of 10 nM. [ABSTRACT FROM AUTHOR]

In the presence of ( R )-SEGPHOS-PdCl 2 catalyst, 5- endo -hydroaminocyclization of various 2-( tert -butyl)- N -(2-ethynylphenyl)anilines proceeds enantioselectively to afford optically active N–C axially chiral N -(2- tert -butylphenyl)indole derivatives in good yields. The enantioselectivity depends strongly on the bulkiness of ortho -substituents and the electron density on the arylethynyl group, and it is explained by the dynamic axial chirality generated by the twisting of the aryl substituent. [ABSTRACT FROM AUTHOR]

Axially chiral N -arylindoles and realated compounds were stereoselectively synthesized using the following three protocols; 1) diastereoselective nucleophilic aromatic substitution, 2) desymmetrization via a stereoselective Cr(CO) 3 migration reaction, and, 3) catalytic enantioselective synthesis via asymmetric ring-closing metathesis. Arene chromium tricarbonyls were utilized as key building blocks, and all of these methods induced extremely high stereoselectivities. Moreover, Cr(CO) 3 fragments were easily removed via air oxidation condition to afford Cr-free N -arylindoles with axially chiral N–C bonds. [ABSTRACT FROM AUTHOR]

The development of efficient and durable catalyst for oxygen reduction reaction (ORR) is critical for the practical application of proton exchange membrane fuel cell (PEMFC). A novel imidazole based ionic liquid is synthesized in this study and used subsequently for the preparation of a N and S co-doped metal-free catalyst with three dimensional ordered microstructure. The catalyst prepared at 1100 °C showed improved ORR catalytic performance and stability compared to commercial Pt/C catalyst. We demonstrate that the high graphitic N content and high degree of graphitization of the synthesized catalyst is responsible for its superb ORR activity. Our results suggest that the N and S co-doped metal-free catalyst reported here is a promising alternative to traditional ORR catalyst based on noble metal. Furthermore, the current study also demonstrate that importance of morphology engineering in the development of high performance ORR catalyst. [ABSTRACT FROM AUTHOR]

The compounds N-(benzylidene)-anilines XArCH=NArY (XBAY), N-(phenyl-ethylene)-anilines XArC(CH3)=NArY (XPEAY) and N-phenyl-α-phenylnitrones XArCH=N(O)ArY (XPNY) have bridging group CH=N, C(CH3)=N and CH=N(O) respectively, in which the C(CH3)=N has a side-group methyl CH3 at carbon end and the CH=N(O) has a side-group O atom at nitrogen end. In this work, a series of XPEAY and XPNY were synthesized, and their longest wavelength maximum λmax (nm) of ultraviolet absorption spectra were measured. Then the change regularity of the νmax (cm-1, νmax=1/λmax) of XPEAY and XPNY were investigated, and they were compared with that of XBAY (reported by ref.26). The results indicate: (1) There are no good linear relationships between the νmax of XBAYs and XPEAYs or XPNYs. (2) In case of a same set of X-Y group couples, the distribution of λmax of XPEAYs is larger than that of XPNYs. (3) The side-group CH3 makes the effect of σ(X) larger than that of σ(Y) on the νmax of XPEAYs, whereas the O atom makes the effect of σ(Y) larger than that of σ(X) on the νmax of XPNYs. (4) The cross-interaction between X and Y has important effect on the all νmax. However, the cross-interaction between CH3 and X/Y has not important effect on the νmax of XPEAY, and the cross-interaction between O and X/Y has not important effect on the νmax of XPNY. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5) significantly impacts global air quality and human health due to its smaller particle size and larger specific surface area. Nitrogen and carbon aerosols, as the main components of PM 2.5 , play key roles in air pollution. This study identified the sources and seasonal variation of nitrogen and carbon aerosols in PM 2.5 in typical cities of Zhejiang. The annual average PM 2.5 concentrations of Hangzhou (HZ), Ningbo (NB), and Huzhou (HUZ) were 39.8 ± 19.1 μg m−‍3, 40.0 ± 21.5 μg m−3, and 50.1 ± 22.6 μg m−3, respectively, which exceeded the Chinese air quality limit of 35.0 μg m−3. The results showed that the concentrations of nitrogen aerosols (NO 3 − and NH 4 +) in water-soluble inorganic ions were higher at 9.6 ± 4.6 μg m−3, 9.0 ± 4.5 μg m−3 and 11.5 ± 5.4 μg m−3 in HZ, NB and HUZ, respectively, especially in winter, accounting for over 60% of the total. The annual average δ15N values of PM 2.5 were 6.2 ± 1.9‰, 6.4 ± 2.2‰ and 6.7 ± 1.9‰ in HZ, NB and HZ, respectively; the δ15N values in winter were relatively low. A Bayesian isotopic mixing model was employed to analyse the sources of nitrogen aerosols in winter; the results showed that nitrogen concentration was mainly affected by NH 3 and NO X emitted by motor vehicle exhaust, coal combustion, biomass combustion, biogenic soil emissions, animal wastes and ocean evaporation (NB). In addition, the carbon component analysis of PM 2.5 showed that the annual average mass concentration of TC accounted for 18.7%, 16.4% and 20.1% of PM 2.5 in HZ, HUZ and NB, respectively. The same isotope model was used to analyse the sources of carbon aerosols; the results showed that carbon aerosols were mainly affected by the sources of motor vehicle exhaust, coal combustion, biomass combustion and dust. In the PM 2.5 in Zhejiang, the most contributory sources of nitrogenous aerosols and carbon aerosols were motor vehicle exhaust sources. [Display omitted] • The fractionation coefficients for nitrogen aerosol conversions are different in Hangzhou, Ningbo, and Huzhou. • The NO X and NH 3 sources of aerosol NO 3 − and NH 4 + in Hangzhou, Ningbo, and Huzhou were identified. • The stable carbon and nitrogen isotope values of dust sources in Hangzhou, Ningbo and Huzhou are significantly different. • The main sources of carbon aerosol are motor vehicle exhaust in Hangzhou, Ningbo and Huzhou. [ABSTRACT FROM AUTHOR]

We could access for the first time a 5-phosphasemibullvalene derivative via quantitative and selective photochemical di-π-methane rearrangement from the corresponding phosphabarrelene. Due to the striking analogy between phosphorus and carbon, this hitherto unknown transformation of vinyl-phosphorus species provides the possibility to prepare novel, chiral and conformationally rigid organophosphorus cage compounds in a straightforward manner. [ABSTRACT FROM AUTHOR]

As electrical energy storage and delivery devices, carbon-based supercapacitors have attracted much attention for advancing the energy-efficient economy. It is important to develop a facile, low-cost and environmentally friendly method of producing novel carbon materials. In this study, we report a scalable synthesis of phosphorus- and nitrogen-co-doped porous carbons using lamellar-structured fish scale. The special lamellar structure of fish scale allows the production of porous carbons with large specific surface areas (up to 1300 m2 g−1) and a high level of mesoporosity. Their inherent organic composition could be adapted with abundant N and P functional groups on the final carbons. Their high levels of porosity and rich surface functionality permit the carbons to exhibit excellent electrochemical performance as electrode materials for supercapacitors. The energy densities of supercapacitors approach 11.7 and 33.1 W h kg−1 in aqueous and IL electrolytes, respectively. [ABSTRACT FROM AUTHOR]

Phenylnitreniumion (PhNH+) may bind to nucleophiles through nitrogen aswell as through C2 or C4 carbons. However, only adducts of the formertype have been hitherto reported after its reaction with purine nucleosides.In this study, reactions of N-acetoxyaniline (PhNHOAc),a precursor to PhNH+, with 2′-deoxyadenosine (dA),2′-deoxyguanosine (dG), and with DNA in vitroat physiological conditions are described. The reaction of PhNHOAcwith dA followed by a hydrolytic deribosylation afforded 8-phenylaminoadenine(C8-PhNHA) together with a smaller amount of N6-(4-aminophenyl)adenine (N6-4APA). A similar reactionwith dG afforded 8-phenylaminoguanine (C8-PhNHG) together with tracesof 7-(4-aminophenyl)guanine (N7-4APG). The same adducts were foundalso in the DNA treated with PhNHOAc, and all of them were identifiedby comparison of their HPLC retention times and MS2spectrawith a set of synthesized authentic adenine adducts at C2, C8, N7, and N6positions and guanineadducts at C8, N7, and N2positions. The newly identified minor adduct, N7-4APG, representsthe first proof of arylnitrenium adduction at the N7 position of dG, which is the prominent site of attack by most C-electrophiles. [ABSTRACT FROM AUTHOR]

The reactivity of new biologically active thymine derivatives substituted with 2-(arylsulfonamidino)ethyl group at N1 and N3 position was investigated in the gas phase using CID experiments (ESI-MS/MS) and by density functional theory (DFT) calculations. Both derivatives show similar chemistry in the negative mode with a retro-Michael addition (Path A) being the most abundant reaction channel, which correlate well with the fluoride induced retro-Michael addition observed in solution. The difference in the fragmentation of N-3 substituted thymine 5 and N-1 substituted thymine 1 in the positive mode relates to the preferred cleavage of the sulfonyl group ( m/z 155, Path B) in N-3 isomer and the formation of the acryl sulfonamidine 3 ( m/z 309) via Path A in N-1 isomer. Mechanistic studies of the cleavage reaction conducted by DFT calculations give the trend of the calculated activation energies that agree well with the experimental observations. A mechanism of the retro-Michael reaction was interpreted as a McLafferty type of fragmentation, which includes H proton shift to one of the neighboring oxygen atoms in a 1,5-fashion inducing N1(N3)-C bond scission. This mechanism was found to be kinetically favorable over other tested mechanisms. Significant difference in the observed fragmentation pattern of N-1 and N-3 isomers proves the ESI-MS/MS technique as an excellent method for tracking the fate of similar sulfonamidine drugs. Also, the observed N-1 and/or N-3 thymine alkylation with in situ formed reactive acryl sulfonamidine 3 as a Michael acceptor may open interesting possibilities for the preparation of other N-3 substituted pyrimidines. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new isolated Schizochytrium sp. LU310 from the mangrove forest of Wenzhou, China, was found as a high producing microalga of docosahexaenoic acid (DHA). In this study, the significant improvements for DHA fermentation by the batch mode in the baffled flasks (i.e. higher oxygen supply) were achieved. By applied the nitrogen-feeding strategy in 1000 mL baffled flasks, the biomass, DHA concentration and DHA productivity were increased by 110.4%, 117.9% and 110.4%, respectively. Moreover, DHA concentration of 21.06 g/L was obtained by feeding 15 g/L of glucose intermittently, which was an increase of 41.25% over that of the batch mode. Finally, an innovative strategy was carried out by intermittent feeding carbon and simultaneously feeding nitrogen. The maximum DHA concentration and DHA productivity in the fed-batch cultivation reached to 24.74 g/L and 241.5 mg/L/h, respectively. [ABSTRACT FROM AUTHOR]

In many arid and semi-arid regions, irrigated vegetable production leads to major carbon (C) and nitrogen (N) losses owing to high turnover rates. The goal of this experiment was therefore to test two amendments, activated charcoal and quebracho tannins, in their ability to stabilize soil organic carbon (SOC) from goat manure application in order to enhance nutrient and water retention. To this end, a 2-year field experiment was conducted on a sandy alluvial soil in Northern Oman investigating the effects of the two amendments either by mixing them with goat manure in the soil (MC and MT) or by applying manure from goats fed 2.5 % charcoal (MC) or 3.6 % tannin (MT) of their daily diet. Mineral fertilizer (NPK) and pure goat manure (M) served as controls. Application rates amounted to 335 kg N ha year and 6.4-8.2 t C ha year (depending on C and N concentrations) and 2.0 and 1.4 t activated charcoal ha year and 2.8 and 1.7 t quebracho tannin ha year (in 2010 and 2011, respectively). Goat manure applications, in general, increased SOC, total N, and basal respiration compared with mineral fertilizer. Mineral fertilizer reduced SOC by −25.5 % and total N by −20 %, whereas organic treatments increased SOC by up to 21 % and total N by 19 to 48 %. Basal respiration ranged between 4.1 and 8.5 μg CO-C day g and was only affected by mineral fertilizer with an average reduction of 25 and 40 % in 2010 and 2011, respectively, compared with organic treatments. The metabolic quotient was not significantly altered by any of the treatments. Charcoal amendments increased SOC by 10.6 % when charcoal was fed to goats and by 21.3 % when charcoal was mixed with manure and reduced net C losses, whereas pure goat manure did not change it significantly. Tannins mixed with manure did not affect soil parameters, whereas tannins fed to goats showed opposite effects to the other goat manure treatments on pH and SOC. [ABSTRACT FROM AUTHOR]

An analytical method for 14 C in environmental water based on a wet-oxidation process was developed. The method can be used to determine the activity concentrations of organic and inorganic 14 C in environmental water, or total 14 C, including in drinking water, surface water, rainwater and seawater. The wet-oxidation of the organic component allows the conversion of organic carbon to an inorganic form, and the extraction of the inorganic 14 C can be achieved by acidification and nitrogen purging. Environmental water with a volume of 20 L can be used for the wet-oxidation and extraction, and a detection limit of about 0.02 Bq/g(C) can be achieved for water with carbon content above 15 mg(C)/L, obviously lower than the natural level of 14 C in the environment. The collected carbon is sufficient for measurement with a low level liquid scintillation counter (LSC) for typical samples. Extraction or recovery experiments for inorganic carbon and organic carbon from typical materials, including analytical reagents of organic benzoquinone, sucrose, glutamic acid, nicotinic acid, humic acid, ethane diol, et cetera ., were conducted with excellent results based on measurement on a total organic carbon analyzer and LSC. The recovery rate for inorganic carbon ranged tween 98.7%–99.0% with a mean of 98.9(±0.1)%, for organic carbon recovery ranged between 93.8% and 100.0% with a mean of 97.1(±2.6)%. Verification and an uncertainty budget of the method are also presented for a representative environmental water. The method is appropriate for 14 C analysis in environmental water, and can be applied also to the analysis of liquid effluent from nuclear facilities. [ABSTRACT FROM AUTHOR]

Under present experiments, EPS and IPS production, monosaccharide composition, and antioxidant activities of C. gracilis were studied for the first time under submerged culture conditions. Effect of different factors on polysaccharides production was studied by orthogonal experiments using one-factor-at-a-time method. Incubation of culture in the medium with capacity 200 mL (675.12 ± 5.01 and 385.20 ± 5.01 mg/L), rotation speed 150 rpm (324.62 ± 3.32 and 254.62 ± 4.62 mg/L), 6-day culture incubation time (445.24 ± 1.11, 216.60 ± 1.71 mg/L), pH 6.0 (374.81 ± 2.52 and 219.45 ± 2.59 mg/L), and temperature 23°C (405.24 ± 1.11 and 215.60 ± 1.71 mg/L) produced higher EPS and IPS, respectively. Maximum EPS and IPS production was observed in the medium supplemented with glucose as a carbon source (464.82 ± 2.12 and 264.42 ± 2.62 mg/L) and yeast extract as a nitrogen source (465.21 ± 3.11 and 245.17 ± 3.24 mg/L), respectively. Carbon to nitrogen ratio for maximum EPS and IPS production was observed as 10 : 1 (395.29 ± 2.15 and 235.62 ± 1.40 mg/L), respectively. Glucose was found to be the major monosaccharide (62.15 ± 7.33%). Both EPS and IPS of C. gracilis showed significant DPPH radical scavenging activity, ABTS radical scavenging activity, reducing power, and iron chelating activity. [ABSTRACT FROM AUTHOR]

The article discusses comb jelly, Mnemiopsis leidyi, an invasive species in northern Europe. Topics include the reproduction potential, fecundity, and formation of bloom abundances by comb jelly. The production rates of its eggs, measurement of carbon and nitrogen content of the eggs and egg cleavage stages, along with its ecological analysis are also mentioned.

Diet is a leading modifiable risk factor for chronic disease, but it remains difficult to measure accurately due to the error and bias inherent in self-reported methods of diet assessment. Consequently, there is a pressing need for more objective biomarkers of diet for use in health research. The stable isotope ratios of light elements are a promising set of candidate biomarkers because they vary naturally and reproducibly among foods, and those variations are captured in molecules and tissues with high fidelity. Recent studies have identified valid isotopic measures of short- and long-term sugar intake, meat intake, and fish intake in specific populations. These studies provide a strong foundation for validating stable isotopic biomarkers in the general US population. Approaches to improve specificity for specific foods are needed; for example, by modeling intake using multiple stable isotope ratios or by isolating and measuring specific molecules linked to foods of interest. [ABSTRACT FROM AUTHOR]

The article discusses the preservation of ancient soil in basal ice for millions of years at the center of the Greenland Ice Sheet. Topics include the authors' analyses of geochemical data from the second Greenland Ice Sheet Project (GISP2), including cosmogenic beryllium-10 (10Be), carbon (C), and nitrogen (N), ice sheet stability through the Pleistocene, and what the preservation of this soil implies about the behavior of the ice.

Codonopsis pilosula is a traditional Chinese herbal medicinal plant and contains various bioactive components, such as C. pilosula polysaccharides (CPPs) and lobetyolin (Lob). Hydrogen peroxide (H 2 O 2) and nitric oxide (NO) are gaseous molecule and have been well known for their ability to relieve some adverse influences on plant from abiotic stress. Endophytic fungus is non-pathogenic plant-associated fungus that could play a significant role in improving plant tolerance by signal molecule. In this work, we determined how inoculation of Trichoderma strain RHTA01 with C. pilosula changed the plant's growth, metabolite accumulation, and related enzyme activity. Results demonstrated that application of Trichoderma strain RHTA01 significantly improved the growth of C. pilosula. Moreover, it noticeably decreased antioxidant enzyme superoxide dismutase (SOD) and catalase (CAT) activity in C. pilosula leaves, reduced the content of H 2 O 2 and malondialdehyde (MDA), and weakened the peroxidation of cell membrane lipids, which reduced the damage of abiotic stress to C. pilosula. Research has shown that it had obvious effects on levels of nitrogen and carbon metabolic enzymes. For example, sucrose synthase (SS) and acid invertase (AI) levels in C. pilosula roots were nearly 1.43 and 1.7 times higher, respectively, than those in the control (CK) group. In addition, it was notable that the production of CPPs and Lob, the most significant secondary metabolites in C. pilosula , were influenced by Trichoderma strain RHTA01. The obtained results indicate that inoculating C. pilosula with Trichoderma stimulates the carbon and nitrogen metabolism of the plant, and helps to increase the content of CPPs and Lob in the root of the plant. [Display omitted] • Application of FG (Trichoderma) can improve the growth of C. pilosula. • With FG applied, it improved the antioxidant properties of C. pilosula. • The FG improves the content of CPPs and Lob of C. pilosula. • The possible mechanisms are explored between Trichoderma and C. pilosula. [ABSTRACT FROM AUTHOR]

The major and minor constituents of cholesterol gallstones were investigated by Laser-induced breakdown spectroscopy. The elements detected in the center and in the shell part were calcium (Ca), carbon (C), copper (Cu), hydrogen (H), magnesium (Mg), nitrogen (N), sodium (Na), oxygen (O) and potassium (K), but Cu was absent from the surface of the cholesterol gallstones. Our experimental results revealed that calcium was a major constituent of cholesterol gallstones. Our results also showed that the concentration of Ca, Cu and Mg were large in the center in comparison with the shell. Laser-induced breakdown (LIB) spectra of both portions of the surface (colored part and discolored part) of the cholesterol gallstones were recorded. The concentrations of sodium and potassium were higher in the non-pigmented (colored) part than in the pigmented part (discolored/pigment), which showed that the deficiency of sodium and potassium was playing a key role in the formation of discoloration at the different locations on the outer surfaces of the cholesterol gallstones. Thus, laser-induced breakdown spectroscopy (LIBS) is a suitable technique for the analysis of cholesterol gallstones without any sample preparation. [ABSTRACT FROM AUTHOR]

C24H18N2O, monoclinic, P21/ n (no. 14), a = 5.9227(7) Å, b = 16.462(2) Å, c = 18.150(2) Å, β = 98.372(2)°, V = 1750.8(4) Å3, Z = 4, Rgt( F) = 0.0353, wRref( F2) = 0.0942, T = 100(2) K. [ABSTRACT FROM AUTHOR]

We studied the energetic behaviors of interstitial and substitution carbon (C)/nitrogen (N) impurities as well as their interactions with the vacancy in vanadium by first-principles simulations. Both C and N impurities prefer the octahedral site (O-site). N exhibits a lower formation energy than C. Due to the hybridization between vanadium-d and N/C-p, the N-p states are located at the energy from −6.00 eV to −5.00 eV, which is much deeper than that from −5.00 eV to –3.00 eV for the C-p states. Two impurities in bulk vanadium, C–C, C–N, and N–N can be paired up at the two neighboring O-sites along the 〈111〉 direction and the binding energies of the pairs are 0.227 eV, 0.162 eV, and 0.201 eV, respectively. Further, we find that both C and N do not prefer to stay at the vacancy center and its vicinity, but occupy the O-site off the vacancy in the interstitial lattice in vanadium. The possible physical mechanism is that C/N in the O-site tends to form a carbide/nitride-like structure with its neighboring vanadium atoms, leading to the formation of the strong C/N–vanadium bonding containing a covalent component. [ABSTRACT FROM AUTHOR]