The measurements of pulsar frequency second derivatives have shown that they are 10 2 -10 6 times larger than expected for standard pulsar spin-down law. Moreover, the second derivatives as well as braking indices are even negative for about half the pulsars. We explain these paradoxical results on the basis of the statistical analysis of the rotational parameters m, _ m and € m of the subset of 295 pulsars taken mostly from the ATNF database. We have found a strong correlation between € m and _ m for both € m > 0 (correlation coefficient r % 0.9) and € m < 0 (r % 0.85), as well as between m and _ m (r % 0.6-0.7). We interpret these dependencies as evolutionary ones due to _ m being nearly proportional to the pulsars' age.The derived statistical relations as well as ''anomalous'' values of € m are well described by assuming the existence of long-time variations of the spin-down rate. The pulsar frequency evolution, therefore, consists of secular change of m ev (t), _ m ev ðtÞ and € m ev ðtÞ according to the power law with n % 5, the irregularities, observed within the timespan as timing noise, and the non-monotonous variations on the timescale of several tens of years, which is larger than that of the timespan. It is possible that the nature of long-term variations is similar to that of short-term ones. The idea of non-constant secular pulsars' braking index n is also analysed.

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Over the past decades, the achievements in astronomical instrumentation have given rise to a number of novel advanced studies related to the analysis of large arrays of observational data. One of the most famous of these studies is a study of transient events in the near and far space and a search for exoplanets. The main requirements for such kinds of projects are a simultaneous coverage of the largest possible field of view with the highest possible detection limits and temporal resolution. In this study, we present a similar project aimed at creating an extensive, continuously updated survey of transient events and exoplanets. To date, the core of the project incorporates several 0.07–2.5 m optical telescopes and the 6-m BTA telescope of the Special Astrophysical Observatory of RAS (Russia), a number of other Russian observatories and the Bonhyunsan observatory of the Korea Astronomy and Space Science Institute (South Korea). Our attention is mainly focused on the description of two groups of small, wide-angle optical telescopes for primary detection. All the telescopes are originally designed for the goals of the project and may be of interest to the scientific community. A description is also given for a new, high-precision optical spectrograph for the Doppler studies of transient and exoplanet events detected within the project. We present here the philosophy, expectations and first results obtained during the first year of running the project.

The problem of direct detection of a black hole event horizon still remains unresolved. Isolated stellar-mass black holes could be ideal objects for solving this problem, since the event horizon would not be screened by the surrounding interstellar plasma due to its low accretion rate. We search for black hole candidates in their presumed birth locations, computed in the assumption that they could have originated in high-mass binaries. Theories predict that isolated black holes should exhibit featureless flat spectra covering the entire electromagnetic range. Objects classified as DC dwarfs (cool white dwarfs with featureless continuum spectra) are among such galactic sources, and they also constitute a good sample for searching for possible black hole candidates among them. We analyze sources with available spectral, photometric, and proper motion data. The final list contains 5 sources that fit the selection criteria.