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The existing shortcomings of the models for determining the thermal conductivity of composite materials with dispersed spherical inclusions raise the issue of creating more advanced calculation methods. This paper proposes a model for determining the thermal conductivity of composite materials, taking into account influence of thermal resistance at the material-inclusion boundary. The analysis of numerical and theoretical calculations showed that the analytical dependence is consistent with the results of numerical modelling for relatively small values of thermal conductivity of the filler and inclusion diameter. This paper considers several models that have been recently developed and that allow calculating thermal conductivity of such materials. They are compared with the model that takes into account influence of thermal resistance of the phase boundary. Applicability intervals of the considered model for various ratios of the thermal conductivity of inclusion material and matrix material are given.

Mafic dykes and large alkaline and carbonatite intrusions of Middle-Late Devonian age are widespread on the Kola Peninsula in NE Fennoscandia. These magmatic rocks are well characterized with petrographic, geochemical and geochronological data but no paleomagnetic results have been reported yet. We studied dolerite dykes from the northern part of the Peninsula and isolated three paleomagnetic components in these rocks. A low-temperature component is aligned along the present-day field, while a major constituent of natural remanent magnetization is an intermediate-temperature component (Decl. = 79.6°, Inc. = 78.5°, α95 = 5,9°, N = 17 sites) that is present in most Devonian dykes but is found in some baked metamorphic rocks and Proterozoic dykes too. Finally, a primary Devonian component could be reliably isolated from two dykes only. Rock-magnetic studies point to presumably primary low-Ti titanomagnetite and/or pure magnetite as the main remanence carriers but also reveal alteration of the primary minerals and the formation of new magnetic phases. The directions of a major component differ from the Middle Paleozoic reference data for Baltica but closely match those for the 190 ± 10 Ma interval recalculated from the apparent polar wander path of the craton. We assume that this Early Jurassic component is a low-temperature overprint of chemical origin. The main impact of the new results is not to mid-Paleozoic or Early Mesozoic times but to much older epochs. Analysis of paleomagnetic data shows that the directionally similar remanences are present in objects with the ages ranging from 500 Ma to ~ 2 Ga over entire Fennoscandia. Hence we argue that an Early Jurassic remagnetization is of regional extent but cannot link it to a certain process and a certain tectonic event. If true, this hypothesis necessitates a major revision of the APWP for Baltica over a wide time interval.

The thermal history of the Kola Peninsula area of NE Fennoscandia remains almost fully unknown because of the absence of any thermochronological data such as apatite and/or zircon fission track or (U Th)/He ages. In order to fill this gap and to constrain the post-Devonian erosion and exhumation history of this region, we present the results of apatite fission track (AFT) dating of eleven samples selected from the cores taken from different depths of the northern part of the Khibina intrusive massif. The Rb Sr isochron age of this alkaline magmatic complex which is located at the center of Kola Peninsula is 368 + 6 Ma (Kramm and Kogarko, 1994). Samples were analyzed from depths between + 520 and − 950 m and yielded AFT ages between 290 and 268 Ma with an age uncertainty (1σ) of between ± 19 Ma (7%) and ± 42 Ma (15%). Mean track lengths (MTL) lie between 12.5 and 14.4 μm. Inverse time–temperature modeling was conducted on the age and track length data from seven samples of the Khibina massif. Thermal histories that best predict the measured data from three samples with the most reliable data show three stages: (1) 290–250 Ma—rapid cooling from > 110 °C to 70 °C/50 °C for lower/upper sample correspondingly; (2) 250–50 Ma—a stable temperature stage; (3) 50–0 Ma—slightly increased cooling rates down to modern temperatures. We propose that the first cooling stage is related to late-Hercynian orogenesis; the second cooling stage may be associated with tectonics accompanying with opening of Arctic oceanic basin. The obtained data show that geothermal gradient at the center of Kola Peninsula has remained close to the modern value of 20 °C/km for at least the last 250 Myr. AFT data show that the Khibina massif has been exhumed not more then 5–6 km in the last 290 Myr.

In this paper we model influenza propagation in the Russian setting using a spatially explicit model and a detailed human agent database as its input. The aim of our research is to assess the applicability of this modeling method using influenza incidence data for the 2010–2011 epidemic outbreak in Saint Petersburg, and to demonstrate the influence of human contact patterns on the simulated influenza dynamics with a real-case scenario. For this purpose, we use several types of synthetic populations which reflect different ways of distributing people among the workplaces and different contact patterns within the households and the workplaces. The agent-based model is implemented to perform the simulations using Python programming language. We show that in the populations where intensive mixing of people occurs, the influenza outbreaks have higher incidence peak and shorter duration, compared to the populations with less variety of contacts. Hence, the features of contact patterns may dramatically alter the course of epidemics in Russian cities and explain the differences between their outbreak dynamics in the situation when infection virulence and the average number of contacts stay the same.