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The location of overwintering sites of six male and six female European pond turtles (Emys orbicularis) were studied using radiotelemetry in Western Poland, over a period of four consecutive seasons. Most of the studied individuals overwintered in the same area during the research; most distances between two consecutive overwintering sites were 0-25 m. However, changes related to the overwintering area were observed, and in such cases the distance between overwintering sites on two consecutive seasons could exceed 2 km. These results can support an efficient conservation strategy of the turtle population. [ABSTRACT FROM AUTHOR]

Transonic discs with accretion rates relevant to intrinsically bright Galactic X-ray sources (L≈10[sup 38]–10[sup 39] erg s[sup -1]) exhibit a time-dependent cyclic behaviour due to the onset of a thermal instability driven by radiation pressure. In this paper we calculate radiation spectra emitted from thermally unstable discs to provide detailed theoretical predictions for observationally relevant quantities. The emergent spectrum has been obtained by solving self-consistently the vertical structure and radiative transfer in the disc atmosphere. We focus on four particular stages of the disc evolution, the maximal evacuation stage and three intermediate stages during the replenishment phase. The disc is found to undergo rather dramatic spectral changes during the evolution, emitting mainly in the 1–10 keV band during outburst and in the 0.1–1 keV band off-outburst. Local spectra, although different in shape from a blackbody at the disc effective temperature, may be characterized in terms of a hardening factor f. We have found that f is more or less constant, both in radius and in time, with a typical value ∼ 1.65. [ABSTRACT FROM AUTHOR]