Adsorption of Industrial Pollutants by Natural and Modified Aluminosilicates

The adsorption ability of natural clay minerals and zeolites is a structurally caused distinguished feature, which determines their physical–chemical properties and almost each area of application. The type of surface active sites responsible for adsorption behavior differs for various structural types of aluminosilicates and varies under modifying agents. The present chapter illustrates the effect of the acid and base modification of natural aluminosilicates on their adsorption behavior in respect to a number of pollutants present in aqueous media. For this, the change of adsorption-structural characteristics of natural clay samples containing representatives of the main groups of clay minerals under activation is considered. Further, the chapter focuses on characterization of surface active sites by means of a new method of a catalytic conversion of 2-methylbut-3-yn-2-ol. The presence of both acid and basic sites on the aluminosilicates surface as well as variations of surface acidity and basicity for different structural types of aluminosilicates under varying conditions of modification is discussed. The third highlight of the chapter encompasses adsorption processes taking place in aqueous solutions of formaldehyde, acetic acid, and ammonium chloride on the surface of natural and activated aluminosilicates. The activating effect of a number of inorganic acids and bases on adsorption equilibrium is compared. The considered mechanism of the adsorption of electrolytes and polar molecules from aqueous media may comprise hydrogen bonding, chemisorptions, or ion-exchange reactions

Zemstvo severnoi oblasti v epokhu rossiiskoi grazhdanskoi voiny

Basé sur les archives de la province (gubernija) septentrionale d’Arhangel´sk, cet article étudie l’activité politique et administrative des zemstva (sing. zemstvo) pendant la guerre civile. Liquidés après l’arrivée au pouvoir des bolcheviks, les zemstva ont repris leurs fonctions avec le gouvernement des Blancs du Nord (mi‑1918 à 1920). L’article souligne que dans les conditions d’un lourd conflit armé et, indépendamment du soutien manifesté par la population, les zemstva n’étaient plus ces lieux de discussion et de prise de décision dédiés à la gestion des problèmes locaux : ils s’étaient transformés en instrument du pouvoir pour mobiliser populations et ressources pour la guerre. La centralisation de l’administration autonome du zemstvo reflétait la consolidation de l’appareil du parti soviétique qui s’était produite du côté rouge du front pendant les années de la guerre civile.The article examines the political and administrative functions of the zemstvos in Arkhangel´sk province in northern Russia during the Civil War. Zemstvos were liquidated in the province in early 1918 after the Bolsheviks’ seizure of power, but later resumed their work under the anti‑Bolshevik Provisional Government of Northern Russia between mid‑1918 and 1920. The reinstated zemstvos enjoyed significant popular support in the North. Still, in the conditions of the Civil War, they abandoned their role as public forums for debating and solving local problems, and instead became an instrument in the government’s policies aimed at mobilizing people and resources for the war. The centralization of the zemstvo self‑government closely mirrored the consolidation of the Bolshevik and Soviet party apparatus that took place at the same time on the other side of the Civil War front

Chitosan polyplex mediated delivery of miRNA-124 reduces activation of microglial cells in vitro and in rat models of spinal cord injury

AbstractTraumatic injury to the central nervous system (CNS) is further complicated by an increase in secondary neuronal damage imposed by activated microglia/macrophages. MicroRNA-124 (miR-124) is responsible for mouse monocyte quiescence and reduction of their inflammatory cytokine production. We describe the formulation and ex vivo transfection of chitosan/miR-124 polyplex particles into rat microglia and the resulting reduction of reactive oxygen species (ROS) and TNF-α and lower expression of MHC-II. Upon microinjection into uninjured rat spinal cords, particles formed with Cy3-labeled control sequence RNA, were specifically internalized by OX42 positive macrophages and microglia cells. Alternatively particles injected in the peritoneum were transported by macrophages to the site of spinal cord injury 72h post injection. Microinjections of chitosan/miR-124 particles significantly reduced the number of ED-1 positive macrophages in the injured spinal cord. Taken together, these data present a potential treatment technique to reduce inflammation for a multitude of CNS neurodegenerative conditions.From the Clinical EditorThe treatment of spinal cord injury remains an unresolved problem. Secondary damage is often the result of inflammation caused by activated microglia and/or macrophages. In this article, the authors developed their formulation of chitosan/miR-124 polyplex particles and investigated their use in the suppression of neuronal inflammation. This exciting data may provide a new horizon for patients who suffer from spinal cord injury

Current issues of the Russian language teaching XIV

Collection of papers “Current issues of the Russian language teaching XIV” is devoted to issues of methodology of teaching Russian as a foreign language, to issues of linguistics and literary science and includes papers related to the use of online tools and resources in teaching Russian. This collection of papers is a result of the international scientific conference “Current issues of the Russian language teaching XIV”, which was scheduled for 8–10 May 2020, but due to the pandemic COVID-19 took place remotely

L’Ukraine occupée, vue de l’intérieur et racontée de l’extérieur

La mémoire des grands événements historiques, et c’est le cas pour la Seconde Guerre mondiale, est façonnée par le lieu, le moment et le contexte dans lesquels ils sont remémorés. Plus l’on s’en éloigne, plus le cours de la vie politique et sociale influe sur les mémoires collective et individuelle. De ce point de vue, les entretiens réalisés dans le cadre du « projet Harvard » sont uniques, à la fois par leur proximité avec les événements, par le choix des thèmes abordés et par une façon par..

How efficiently combine sonochemistry and clay science?

International audienceClays are widespread materials of natural origin, possessing various surface active sites, exchangeable and structural cations, as well as micro- and mesoporous structures that allow their application in ion-exchange, adsorption and catalytic processes. A recent trend has been to combine clays to ultrasound irradiations (sonochemistry) in a range of different applications and the results demonstrate significant and occasionally surprising synergetic effects. Indeed, ultrasound can lead to significant changes in the properties and behaviors of clays depending on the choice of ultrasonic parameters. Here, the advantages and limitations of the clay science/sonochemistry combination have been critically highlighted in different applications, to understand how, and in which respects, ultrasound could become an essential and efficient tool of clay chemistry in the future

Non-thermal atmospheric plasma: Opportunities for the synthesis of valuable oligosaccharides from biomass

International audienc

Biodegradable fibrin conduit promotes long-term regeneration after peripheral nerve injury in adult rats

Peripheral nerve injuries are often associated with loss of nerve tissue and require autologous nerve grafts to provide a physical substrate for axonal growth. Biosynthetic neural conduits could be an alternative treatment strategy in such injuries. The present study investigates the long-term effects of a tubular fibrin conduit on neuronal regeneration, axonal sprouting and recovery of muscle weight following peripheral nerve injury and repair in adult rats. Sciatic axotomy was performed proximally in the thigh to create a 10-mm gap between the nerve stumps. The injury gap was bridged by using a 14-mm-long fibrin glue conduit, entubulating 2 mm of the nerve stump at each end. A reversed autologous nerve graft was used as a control. The regenerative response from sensory and motor neurones was evaluated following retrograde labelling with Fast Blue fluorescent tracer. In control experiments, at 16 weeks following peripheral nerve grafting, 5184 (±574 standard error of mean (SEM)) sensory dorsal root ganglion neurones and 1001 (±37 SEM) spinal motor neurones regenerated across the distal nerve-graft interface. The fibrin conduit promoted regeneration of 60% of sensory neurones and 52% of motor neurones when compared to the control group. The total number of myelinated axons in the distal nerve stump in the fibrin-conduit group reached 86% of the control and the weight of gastrocnemius and soleus muscles recovered to 82% and 89% of the controls, respectively. The present results suggest that a tubular fibrin conduit can be used to promote neuronal regeneration following peripheral nerve injury