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Crinoids of the Order Comatulida are renowned for harboring a remarkable diversity of symbiotic organisms within echinoderms, including polychaetes, myzostomids, gastropods, crustaceans, brittle stars, or fish. Crinoids provide essential services to their symbionts, such as shelter, access to food resources, mating areas, nesting grounds, and nurseries. Symbionts within crinoids developed a variety of strategies, including foraging in the arm ambulacral grooves, preying upon other symbionts, living within galls, or accessing suspended food particles from the water column. In this work, we focused on the Great Reef of Toliara, where we collected specimens from seven crinoid species. Among the 84 crinoids examined, a total of 285 symbiotic organisms were retrieved. These symbionts were either moving freely on their host or found within cysts. Stable isotope analyses of carbon and nitrogen for both hosts and symbionts have shown that (a) all crinoids shared a common trophic niche; (b) a community-based approach indicated that crinoids initiated trophic networks primarily based on suspended particulate organic matter; (c) non-specific symbionts exhibited consistent dietary preferences regardless of their host; (d) myzostomids inhabiting cysts were found to feed on their host tissues; and (e) free-moving symbionts displayed divergent trophic niches linked to their predatory, kleptoparasitic, or filter-feeding behaviors. This research underscores the role of crinoids, particularly comatulid species, as key components of tropical ecosystems in the Western Indian Ocean, inhabited by a hidden biodiversity with complex trophic networks. Their intricate morphology accommodates a range of feeding strategies, supporting a diverse associated fauna. [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]

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]

Imidazolinium l-tartrate (IMLT) crystals and l-histidine-doped IMLT crystals were grown by slow evaporation technique at room temperature. The powder x-ray diffraction technique confirms the lattice parameters and shifts in the peak positions attributed to the dopant l-histidine. The Fourier transform infrared (FTIR) spectrum reveals the assignments of characteristic bondings present in the grown crystals. The frequency-dependent dielectric constant and dielectric loss of pure and l-histidine-doped IMLT crystals have been investigated by the dielectric measurements. Doping has improved the optical parameters and was studied using UV–Vis-near infrared (NIR) spectral studies. The cut-off wavelengths of pure and 1 mol.% l-histidine-doped IMLT crystals were observed at 234 nm and 229 nm, respectively. The etching study examines the growth mechanism and surface morphology of the pure and l-histidine-doped IMLT crystals. The carbon-hydrogen-nitrogen (CHN) analysis conveys the percentage of carbon, hydrogen and nitrogen elements present in pure and l-histidine-doped IMLT crystals. The consequences of doping l-histidine in IMLT single crystal and their dominance in various properties of the crystal grown in aqueous solution by slow evaporation technique have been explored. [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]

The present study focuses on comparison of accuracy of Johnson-Cook, modified Johnson-Cook, and modified Zerilli-Armstrong constitutive models to predict flow behavior of a nitrogen-alloyed ultralow carbon stainless steel at evaluated temperature. True strain-true stress data obtained from hot compression experiments performed with temperatures of 1223-1423 K and strain rates of 0.001-10 s on a Gleeble-3500 thermal-simulator were employed to develop these three models. Furthermore, the ability of the three models to predict the outcomes was evaluated by comparing the correlation coefficient, absolute average related error, ability to track the experimental flow stress, numbers of material constants, and computational time required to develop models. The results show that the modified Johnson-Cook has a better description of the flow behaviors of the studied steel than the other two models. However, under certain conditions, the modified Zerilli-Armstrong model has accuracy comparable to the modified Johnson-Cook model. [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]