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This paper presents the results of high‐resolution sedimentological analyses of sediment cores from the eastern Gulf of Finland (Baltic Sea). Sampling sites in the periphery of sedimentary basins were selected on the basis of acoustic profiling analyses. The research allowed tracing of the transition from the freshwater Ancylus Lake to the Littorina Sea. A specific transitional layer of 'blue clays', indicating the first stage of brackish water inflow into the Gulf of Finland, was dated to 9.1 ka BP. The date of first appearance of Littorina silty clay sedimentation was as follows: from 8.0 ka BP near Gogland Island, from 7.0 ka BP near Moshchny Island and from 5.9 ka BP near the Berezovye Islands. Holocene cycles of hypoxia, associated with periods of warming, were identified and cycles of 'warming – transgression – anoxic conditions' and 'cooling – regression – oxygen‐rich conditions' were revealed. During the first stage of Littorina transgression (8.0–7.0 ka BP), the near‐bottom environment in the deepest sedimentary basin of the eastern Gulf of Finland was characterized by oxygen deficiency. In contrast, 7.0–6.0 ka BP was dominated by oxygen‐rich conditions and active processes of bioturbation. Anoxic conditions occurred again from 6.0–4.8 ka BP (Holocene Climatic Optimum), resulting in the accumulation of undisturbed silty clays with subhorizontal lamination. The interval from 4.8–2.0 ka was then characterized by oxygen‐rich near‐bottom conditions favourable for benthic organisms. The grain‐size distributions throughout the sediment cores from the easternmost sedimentary basins suggest a relative lowering of the sea level from 3.5–1.8 ka and a rise after 1.8 ka BP. [ABSTRACT FROM AUTHOR]

In the work, the psychophysical model of the signal detection theory with the nine outcomes (PMSDT9) for a quantitative description of the solution of the sensory problem of detecting an alternating differential signal was proposed. Unlike the classical model, PMSDT9 has the three probability density functions of the subjective intensity and the sign of the differential signal (instead of the two), the two criteria of displacement (instead of the one), and the nine outcomes (instead of the four). The proposed PMSDT9 model generalizes the application of the classical model of the signal detection theory for the less‐equal‐more task. The modified model provides for the existence of the two criteria (the left and the right) and such outcomes as inversion. The obtained experimental results are consistent with the ideas about the noise in sensory systems. [ABSTRACT FROM AUTHOR]

A unique geological process of extrusion of lagoon marl from beneath massive migrating sand dunes is characteristic for large segments of the Curonian Spit - a ~100-km-long sandy barrier that separates the Curonian Lagoon from the Baltic Sea. Exposures of a composite set of Holocene organic sediments such as gyttja, clayey gyttja and gyttja clay, collectively referred to as 'lagoon marl', are common along the northern half of the lagoon coast of the spit. The marl outcrops rise up to 3-4 m above the lagoon level and owe their origin to extrusion from their 7-8 m in situ depth beneath the present regional water table. New detailed investigations of the Baltic Sea bottom along the southern half of the Curonian Spit using side-scan sonar, a multibeam echosounder, seismic imaging, sediment sampling and video observations allowed identification and mapping of a unique underwater landscape formed by extensive outcrops of laminated and folded lagoon marl at water depths of 5-15 m. The combined onshore-offshore database indicates that relict lagoon marl was deformed, compacted and dehydrated by a massive dune-covered coastal barrier migrating landward (retrograding) over these sediments during the Littorina Sea transgression in a processes termed 'dune tectonics'. Spatial analysis of the relict sediments traced in offshore geophysical data helped to constrain the rates of the southeast migration of the dune massif. A conceptual model is presented to explain the present context of marl exposures above the regional water table, as well as the occurrence of relict lagoon marl extrusions (diapirs) on the underwater marine slope of the Curonian Spit. [ABSTRACT FROM AUTHOR]

The article focuses on the study about the viability of bioaerosols in the atmosphere and questioned the extent of the health risk posed by the viable bacteria present in atmospheric aerosols. It evaluates the pathogenic of airborne bacteria to its effect on regional population in western Siberia in Russia. The use of feasible risk assessment method for a routine monitoring of atmospheric aerosols is discussed. The pathogenic of particular microorganism, concentration of these microorganisms in the air, resistance to environmental factors, and antibiotic resistance are also presented. The results were characterized for each factor by a proposed integral index quantitatively reflecting the contribution of this factor toward potential seasonal risk for the human population.