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The reusability of spent adsorbents is the most important characteristic for their practical application. The process of MgFe2O4 regeneration after methylene blue (MB) adsorption was studied. The effect of the nature (HCl, HNO3, and MgCl2) and the concentration (10-3-10-1 M) of regeneration agents was established. All the regeneration agents at 10-3 and 10-2 M had high efficiency and adsorption capacity recovery reached 80-90%, whereas for 10-1 M concentration the adsorption efficiency was in the range of 4.5-36.2%. It was shown that the concentration of desorbed MB was much less than what had been previously adsorbed and did not correlate with regeneration efficiency. The unusual behavior of MgFe2O4 during regeneration could be due to different mechanisms of regeneration by OH3 þ and Mg2+ ions: (i) for acidic regeneration the main process was the non-specific adsorption of OH3 þ ions in a diffusion layer and the substitution of adsorbed MB due to electrostatic forces; (ii) in the case of Mg2+ as a regeneration agent, there was specific adsorption due to the completion of a crystal lattice of MgFe2O4 nanoparticles by Mg2+ ions (according to the rules of Fayans-Pannet) with the formation of new Mg-OH adsorption sites and the super-equivalent adsorption of Mg2+ ions (according to DLVO (Derjaguin, Landau, Verwey, and Overbeek) theory) accompanied by a recharge of the MgFe2O4 surface. These phenomena of MgFe2O4 regeneration using Mg2+ ions must be taken into account in the theory and practice of adsorption. [ABSTRACT FROM AUTHOR]

The development of rapid, accurate and reliable methods to detect mold in medicinal products is an important challenge, especially for sterility testing. The objective of this study was to optimise fungal detection using the BacT/ALERT 3D DUAL-T microbial detection system with a maximum of 7 days of incubation. The influence of incubation temperature and culture medium was investigated. A total of four Aspergillus spp. and one Penicillium spp. were used in this study. The comparison of parameters, such as limit of detection (LOD), time to detection (TTD) and inoculation techniques, was carried out. The data demonstrated that the BacT/ALERT 3D DUAL-T system and the compendia method revealed similar LOD. The most appropriate culture medium bottle was iLYM. Venting of this medium prior to use decreased the TTD although this difference was not significant. The length of venting time had no effect on fungal growth. [ABSTRACT FROM AUTHOR]

Abstract: Optical coupling between a single, individually addressable neuron and a properly designed optical fiber is demonstrated. Two‐photon imaging is shown to enable a quantitative in situ analysis of such fiber–single‐neuron coupling in the live brain of transgenic mice. Fiber‐optic interrogation of single pyramidal neurons in mouse brain cortex is performed with the positioning of the fiber probe relative to the neuron accurately mapped by means of two‐photon imaging. These results pave the way for fiber‐optic interfaces to single neurons for a stimulation and interrogation of individually addressable brain cells in chronic in vivo studies on freely behaving transgenic animal models, as well as the integration of fiber‐optic single‐neuron stimulation into the optical imaging framework. [ABSTRACT FROM AUTHOR]

Up to date, rodent fear conditioning is the most commonly used model of mammalian associative memory in neurobiology. Since the mechanisms of associative memory in this model are mainly studied using audi tory fear conditioning, the question about the generality of this mechanisms in respect to other conditioned stimuli remains open. The aim of this work-was to compare dynamics of visual-and auditory fear memory for- mation and retrieval. We showed that acquisition of freezing in response to visual conditioned stimulus is significantly slower in comparison with the. auditory conditioned stimulus. Moieover, the dynamics of memory retrieval was different in animals, trained to these stimuli, being slower in response to visual conditioned stim- ulus. This may reflect distinct mechanisms of visual and auditory associative memory consolidation or re- trieval in this Model. Our results impose constraints on the generality of conclusiois about the dynamics as- sociative memory formation obtained solely from classical auditory fear conditioning model in mice.