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The basal tills of the Late Moscow (MIS 6) Cryochrone form an important component of landscapes in northern Europe, including the center of the Russian Plain. The till is often covered only with a thin cover layer (30–50 cm as an average) – veneers of sands, sandy loams or silty loams, so that surface soils (Retisols) are formed in the bipartite sediments. The study of such soils allows identifying a set of pre-depositional, syn-depositional and post-depositional (pedogenic and cryogenic) features. An assemblage of (macro, meso and micro) morphological features together with analytical data confirmed that soils had been formed within several climatic cycles starting from the Late Moscow time till now, including the last Thermochrone, when the well-developed Argic horizon had been formed. Modern pedogenesis forms embedded profiles within the cover layer depending on the bioclimatic parameters (with Humic, Protospodic or Cambic horizons). The clear record of the final stages of sedimentation and ancient pedogenesis within profiles of soils in bipartite sediments may help to derive paleoclimatic interpretations from the last interglacial - glacial cycle till present. Correlation of these records with other archives in glacial and periglacial areas opens attractive research perspectives.

Vladimir Opolie is a typical loess island with soil pattern that differs strikingly from that of adjacent territories. Soils are characterized by a controversial set of features. They have common features with other loess islands located in various environmental zones (similar dependence on microtopography with second humus horizons in soils within depressions and accumulation of carbonates in soils on the main surfaces). On the other hand they differ from soils of loess islands formed on typical loess due to specific features of sediments: mantle loams, and a northern variety of loess. A pedostratigraphic approach to the study of soils of Vladimir Opolye reveals that constitution of the upper loess strata depends on paleocryogenic microtopography and that relict soil features (second humus horizon, pattern of carbonates distribution) are syngenetic with the final stages of loess sedimentation. The abundance of relict features indicates that the soils of Vladimir Opolie are surface paleosols.

We propose a flexible simplified extended Kalman filter (S-EKF) scheme that can be applied in both pilot-aided and blind modes for phase noise compensation in 16-QAM CO-OFDM transmission systems employing a small-to-moderate number of subcarriers. The performance of the proposed algorithm is evaluated and compared with conventional pilot-aided (PA) and blind phase search (BPS) methods via extensive an Monte Carlo simulation in a back-to-back configuration and with a dual polarization fiber transmission. For 64 subcarrier 32 Gbaud 16-QAM CO-OFDM systems with 200 kHz combined laser linewidths, an optical signal-to-noise ratio penalty as low as 1 dB can be achieved with the proposed S-EKF scheme using only 2 pilots in the pilot-aided mode and just 4 inputs in the blind mode, resulting in a spectrally efficient enhancement by a factor of 3 and a computational effort reduction by a factor of more than 50 in comparison with the conventional PA and the BPS methods, respectively.