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The Kagome antiferromagnet Mn 3 Sn has garnered much attention due to the presence of exciting properties such as anomalous Hall and Nernst effects. This paper discusses the synthesis of crystalline Mn 3 Sn thin films, prepared on Al 2 O 3 (0001) substrates at 453 ± 5 ° C using molecular beam epitaxy. The growth is monitored in situ using reflection high energy electron diffraction and measured ex situ using x-ray diffraction, Rutherford back-scattering, and cross-sectional scanning transmission electron microscopy. Our analysis shows the in-plane lattice constants of a 1 , M = 4.117 ± 0.027 Å and a 2 , M = 4.943 ± 0.033 Å, which is a very unexpected result when compared to the bulk a -plane Mn 3 Sn. This indicates a strain in the film and makes it challenging to provide a straightforward explanation. In an effort to explain our results, we discuss two possible orientation relationships between the Mn 3 Sn films and the sapphire substrates. Samples prepared under these conditions appear to have smooth surfaces locally, but overall the film has a 3D island morphology. First-principles calculations provide atomic models of the Mn 3 Sn (11 2 ¯ 0) lattice on Al 2 O 3 (0001) high symmetry sites, indicating that the L3-R90 ° is the most stable configuration. A detailed discussion of the experimental data and theoretical results, as well as strain effects, is provided. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to determine the uptake and distribution of zinc ions (Zn2+) in two freshwater organisms, Moina macrocopa and Rheocricotopus larvae using a high-affinity low-molecular-weight Zn2+-ion-selective fluorescence probe. Methods: M. macrocopa and Rheocricotopus larvae were exposed separately to dissolved Zn2+ (0.1 and 1 mg/L) for 12, 24, and 48 h in three replicates along with a control. Later, the organisms were incubated with the fluorescence probe in six-well plates in the dark at room temperature. At the end of the incubation period, the organisms were washed with a phosphate buffer solution (0.01 M). The live organisms were then imaged using a fluorescence microscope and the fluorescence intensities of the images were determined. Results: The results revealed that the Zn2+ ions are uptaken and internalized into the bodies of the organisms exposed to Zn2+ ion concentrations, as indicated by a significant increase in the fluorescence intensities of the fluorescence images of the organisms. According to the fluorescence images, the Zn2+ ions were mainly localized in the lower gut region of M. macrocopa at the end of 48 h. However, in Rheocricotopus larvae, the Zn2+ ions were detected in the midgut region of the digestory tube after 48 h of exposure. Therefore, this was dependent upon both the Zn2+ concentration in the exposure media and the exposure duration. Conclusion: Taken together, the distribution of Zn2+ ions in different aquatic species is species-specific. Furthermore, the present study provides insight into the potential use of high-affinity low-molecular-weight Zn2+-ion-selective fluorescence probes to detect labile Zn2+ in aquatic organisms and the toxicological implications of zinc pollution in aquatic environments. [ABSTRACT FROM AUTHOR]

Stinging nettle ( Urtica dioica. L) is a wild, unique herbaceous perennial flowering plant with Stinging hairs. It has a long history of use as a food sources as a soup or curries, and also used as a fiber as well as a medicinal herb. The current aim was to analyze the composition and bioactive compounds in Nepalese Stinging nettle. Chemical analysis showed the relatively higher level of crude protein (33.8%), crude fiber (9.1%), crude fat (3.6%), total ash (16.2%), carbohydrate (37.4%), and relatively lower energy value (307 kcal/100 g) as compared to wheat and barley flours. Analysis of nettle powder showed significantly higher level of bioactive compounds: phenolic compounds as 129 mg Gallic acid equivalent/g; carotenoid level 3497 μg/g; tannin 0.93 mg/100 g; anti-oxidant activity 66.3 DPPH inhibition (%), as compared to wheat and barley. This study further established that nettle plants as very good source of energy, proteins, high fiber, and a range of health benefitting bioactive compounds. [ABSTRACT FROM AUTHOR]