Correspondence regarding the Perspective article “Addressing the importance of microplastic particles as vectors for long‐range transport of chemical contaminants: perspective in relation to prioritizing research and regulatory actions”

Important clarifictions regarding the long-range environmental transport of chemical additives contained in floating plastic debris are presented.

Evaluation of an Environmental Transport Medium for Legionella pneumophila Recovery

The collection and storage of water-related matrices such as biofilm from collection to processing are critical for the detection of Legionella pneumophila by cultural and molecular tests. SRK™ is a liquid medium that acts both as an antimicrobial neutralizing agent and a transport medium for bacterial culture enumeration and is useful to maintain the stability of the sample from collection to analysis. The aims of this study were to evaluate Legionella pneumophila viability and bacterial nucleic acids’ stability in SRK™ medium over time at different storage conditions. Artificial bacterial inoculates with an approximate concentration of 104, 103 and 102 CFU/mL were made using Legionella pneumophila certified reference material suspended in SRK™ medium. Bacteria recovery was analyzed by cultural and molecular methods at time 0, 24 and 48 h at room temperature and at 0, 24, 48 and 72 h at 2–8 °C, respectively. SRK™ medium supported Legionella pneumophila culture viability with CFU counts within the expected range. The recovery after 72 h at 2–8 °C was 83–100% and 75–95% after 48 h at room temperature. Real-time PCR appropriately detected Legionella pneumophila DNA at each temperature condition, dilution and time point. Results demonstrated a good performance of SRK™ medium for the reliable recovery of environmental Legionella.

Kazakhstan and Prospects for Regional Cooperation in Central Asia

A number of factors hinder regional cooperation in Central Asia. They include multidirectional foreign policy priorities of the countries of the region and unresolved acute regional problems (territorial borders, water and energy, environmental, transport and communication, agricultural and food). The ruling elites of the countries of the region may fail to resist the temptation to channel population's dissatisfaction with the difficult socio-economic situation into the mainstream of interethnic and interstate conflicts. Therefore, there can be no question of Central Asian integration.

Quantifying proximity, confinement, and interventions in disease outbreaks: a decision support framework for air-transported pathogens

The inability to communicate how infectious diseases are transmitted in human environments has triggered avoidance of interactions during the COVID-19 pandemic. We define a metric, Effective ReBreathed Volume (ERBV), that encapsulates how infectious pathogens transport in air. This measure distinguishes environmental transport from other factors in the chain of infection, thus allowing quantitative comparisons of the riskiness of different situations for any pathogens transported in air, including SARS-CoV-2. Particle size is a key factor in transport, removal onto surfaces, and elimination by mitigation measures, so ERBV is presented for a range of exhaled particle diameters: 1 μm, 10 μm, and 100 μm. Pathogen transport is enhanced by two separate but interacting effects: proximity and confinement. Confinement in enclosed spaces overwhelms proximity after 10-15 minutes for all but the largest particles. Therefore, we review plausible strategies to reduce the confinement effect. Changes in standard ventilation and filtration can reduce person-to-person transport of 1-μm particles (ERBV1) by 13-85% in residential and commercial situations. Deposition to surfaces competes with intentional removal for 10-μm and 100-μm particles, so the same interventions reduce ERBV10 by only 3-50%, and ERBV100 is unaffected. Determining transmission modes is critical to identify intervention effectiveness, and would be accelerated with prior knowledge of ERBV. When judiciously selected, the interventions examined can provide substantial reduction in risk, and the conditions for selection are identified. The framework of size-dependent ERBV supports analysis and mitigation decisions in an emerging situation, even before other infectious parameters are well known.

Features of the formation of the St. Petersburg agglomeration by the beginning of the XX century

The study of the Russian historical St. Petersburg agglomeration at all stages from its foundation (from 1703) until the final imperial stage (1917) required the use of complex functional, urban-planning and landscape, socio-economic, environmental, transport and communication analysis on the basis of data from archives, historical cartography and iconography. The main results were the conclusions that during the XVIII - early XX centuries, there was a crystallization of a huge agglomeration around the city of St. Petersburg, which included three belts: “external”, “middle”, “nearby”, which spatially extended from Yaroslavl (in Central Russia) to Riga (in the Baltic). The paper discusses the features of the formation of the “nearby belt” of agglomeration in the initial (1703 - January 1725) and in the final (1901-1916) development periods. The study revealed a significant role of special types of objects in these processes - estates of the aristocratic society and “garden cities” that provided a belt (around St. Petersburg and the largest settlements and complexes), linear (along radial and ring highways), and nodal (around individual large settlements) construction, spreading in the latitudinal direction from Narva and Ivangorod to the mouth of the Syas river, and in the meridian direction - from Vyborg to the city of Luga. Within the boundaries of this agglomeration zone, four sub-agglomerations had begun to emerge since the 1710s and have fully formed by the 1910s. The materials of the paper can be useful both for historians of urban planning and for modern urbanists.