Effect of Silver Nanoparticle Size on Antibacterial Activity.

The ubiquitous use of products containing AgNPs results in the entry of nanoparticles into the environment. Both nanoparticles and Ag released upon their oxidative dissolution have a toxic effect on living microorganisms. The antibacterial activity of spherical silver nanoparticles of 10.

Oxidative Dissolution and the Aggregation of Silver Nanoparticles in Drinking and Natural Waters: The Influence of the Medium on the Process Development.

Currently, there are quite a few data on the ways silver nanoparticles get into the aquatic environment, on their subsequent dissolution in water, and on the release of toxic Ag ions. Differences in the experimental conditions hinder the determination of the basic regularities of this process. In this study, the stages of oxidative dissolution of AgNPs were studied, starting from the formation of silver hydrosol in deaerated solution, the reaction of silver with oxygen and with drinking and natural waters, the analysis of intermediate species of the oxidized colloidal particles, and the subsequent particle aggregation and precipitation, by optical spectroscopy, DLS, TEM, STEM, and EDX.

[Artificial ventilation in patients with stroke: main results of the Russian multicenter observational clinical trial RETAS].

Objective: To analyze the relationship between the characteristics of respiratory support (RS) for patients with stroke and clinical factors with the number and structure of complications, deaths, and length of stay in the intensive care unit (ICU) and duration of artificial pulmonary ventilation (ALV).

Material And Methods: The Russian multicenter observational clinical study «Respiratory Therapy for Acute Stroke» (RETAS) that enrolled 1289 patients with stroke requiring RS was conducted under the auspices of the All-Russian public organization «Federation of Anesthesiologists and Resuscitators». Indications for ALV, the use of hyperventilation, the maximum level of positive end-expiratory pressure, starting modes of mechanical ventilation, timing of tracheostomy, the incidence of protein-energy malnutrition (PEM) and infectious complications were analyzed.

Quantitative assessment of soil condition, basic environmental factors and productivity of Linum usitatissimum in the steppe zone of Kazakhstan using the remote sensing method.

The influence of environmental factors, such as lack of water and uneven rainfall, depletion of nutrients in the soil and reduced soil fertility, planting patterns and plant density, uneven growth stages, are the main limiting factors that hinder the growth of agricultural production in arid regions. The aim of the study was to assess the potential of Sentinel-2 to quantify soil conditions, which can improve the understanding of spatiotemporal dynamics in organic agriculture in the steppe zone of Kazakhstan and improve productivity management of Linum usitatissimum. In the course of the research, the influence of individual factors of the general environmental impact, such as the influence of humidity, meteorological conditions, the content of individual nutrient components of the soil on the yield, was studied.

Electrochemical Mechanism of Oxidative Dissolution of Silver Nanoparticles in Water: Effect of Size on Electrode Potential and Solubility.

For the first time, an electrochemical mechanism of oxidative dissolution of silver nanoparticles in aqueous solutions is suggested and substantiated. The dissolution is caused by the occurrence of two interrelated electrochemical processes: (1) silver oxidation on a microanode and (2) oxygen reduction on a microcathode. According to the suggested model, the standard electrode potential of a nanoparticle decreases with a decrease in its size, which leads to an increase in the electromotive force of the oxidative dissolution of silver.