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Ternary eutectic Mg 76.87 Ni 12.78 Y 10.35 (at. %) ribbons with mixed amorphous and nanocrystalline phases were prepared by melt spinning. The microstructures of the melt-spun, hydrogenated and dehydrogenated samples were examined and compared by X-ray diffraction and transmission electron microscopy. The amorphous structure transforms into a thermally stable nanocrystalline structure with a grain size of about 5 nm during hydrogen ab/desorption cycles. The Mg, Mg 2 Ni and phases with Y in the melt-spun state transform into MgH 2 , Mg 2 NiH 4 , Mg 2 NiH 0.3 , YH 2 and YH 3 after hydrogenation, and transform back to Mg, Mg 2 Ni and YH 2 upon subsequent dehydrogenation. The reaction enthalpy (ΔH) and entropy (ΔS) of the higher plateau pressure corresponding to Mg 2 Ni hydride formation are −53.25 kJ mol−1 and −107.74 J K−1 mol−1, respectively. The amorphous/nanocrystalline structure effectively reduces the enthalpy and entropy of Mg 2 Ni hydride formation, but has little effect on Mg. The activation energy for dehydrogenation of the hydrogenated ribbons is 69 kJ mol−1. This suggests that Mg–Ni–Y with ternary eutectic composition can form an amorphous/nanocrystalline structure by melt spinning, and this nanostructure efficiently improves the thermodynamics and kinetics for hydrogen storage. • Ternary eutectic Mg–Ni–Y and melt spinning are used to maximize the amorphous. • Amorphous Mg–Ni–Y becomes nanocrystalline structure with a grain size of only 5 nm. • Nanocrystalline structure is stable in hydrogenation and dehydrogenation processes. • Low enthalpy and activation energy are achieved in this nanostructured alloy. [ABSTRACT FROM AUTHOR]

Abstract: Exposure to chronic stress in rodents and psychosocial stress in humans has been shown to alter cognitive functions and has been linked to the pathophysiology of mood disorders. The purpose of the present study was to investigate effects and possible mechanisms of a chronic mild stress (CMS) procedure on cognitive behaviors in Swiss albino mice using the object recognition test (ORT) and object location test (OLT). Results showed that CMS exposure impaired cognitive performance and produced amnesia of acquired information in both ORT and OLT. Furthermore, the cognitive impairment was coexistent with increased plasma levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), as well as with enhanced plasma levels of corticosterone (CORT), corticotrophin-releasing hormone (CRH) and adrenocorticotrophic hormone (ACTH). In addition, severe neuronal cell damage was found, as bromodeoxyuridine (BrdU) positive cells and the expression of brain derived neurotrophic factor (BDNF) in dentate gyrus (DG) of hippocampus were decreased after 5 weeks CMS procedure. Taken together, these findings indicated that CMS exposure-induced impairment of cognitive behaviors might be attributed to the stress-related alterations in brain homeostasis that were reflected in changes in the neuroimmune and neuroendocrine systems as well as in neurogenesis. [Copyright &y& Elsevier]