We studied ranging and feeding behavior of Cypriot fruit bats during the summer and winter, which are critical periods with limited food supply and adverse conditions. Seasonal changes in ranging behavior were characterized by a steep increase in the size of core feeding areas and home ranges from summer to winter. Males and females did not differ in the size of summer and winter core areas and home ranges, but they differed in the distance they traveled to summer feeding sites. Summer food consisted of fruits of Ficus carica and flowers of Agave americana. Winter food consisted of dates, fruits of Melia azedarach, Citrus reticulata, C. limon, Myrtus communis, and the flowers of Eucalyptus spp. Males and females differed as to the proportion of time they spent feeding on different food types, which may be explained by sexual differences related to food quality requirements. Summer foraging activity tended to be in areas with water bodies and larger fruit orchards. Winter foraging activity occurred more in areas with larger fruit orchards, a higher number of citrus plantations and date palms, typically located in built-up areas. The body condition of the bats was worse during the summer, which we assume was the result of their more limited diet during this period, making summer a more stressful period for them than winter. Active conservation management of Cypriot fruit bats should include the construction of artificial water sources in the vicinity of fruit orchards, but also controversial practices such as supporting the occurrence of particular nonnative plant species, thereby enhancing food availability in critical times of the year.

We have proposed an approach to the interference phase extraction in the homodyne laser interferometry. The method employs a series of computational steps to reconstruct the signals for quadrature detection from an interference signal from a non-polarising interferometer sampled by a simple photodetector. The complexity trade-off is the use of laser beam with frequency modulation capability. It is analytically derived and its validity and performance is experimentally verified. The method has proven to be a feasible alternative for the traditional homodyne detection since it performs with comparable accuracy, especially where the optical setup complexity is principal issue and the modulation of laser beam is not a heavy burden (e.g., in multi-axis sensor or laser diode based systems).

The infrastructure essentialities for accurate time and stable frequency distribution are presented. Our solution is based on sharing fibers for a research and educational network carrying live data traffic with time and frequency transfer in parallel. Accurate time and stable frequency transmission uses mainly dark channels amplified by dedicated bidirectional amplifiers with the same propagation path for both directions of transmission. This paper targets challenges related to bidirectional transmission, particularly, directional nonreciprocities.

We collected and analyzed data on the annual course of reproduction of the Egyptian fruit bat ( Rousettus aegyptiacus ) in 2 climatically distinct a

Animals are faced with a range of ecological constraints that shape their behavioural decisions. Habitat features that affect resource abundance will also have an impact, especially as regards spatial distribution, which will in turn affect associations between the animals. Here we utilised a network approach, using spatial and genetic data, to describe patterns in use of space (foraging sites) by free-ranging Egyptian fruit bats (Rousettus aegyptiacus) at the Dakhla Oasis in Egypt. We observed a decrease in home range size during spring, when food availability was lowest, which was reflected by differences in space sharing networks. Our data showed that when food was abundant, space sharing networks were less connected and more related individuals shared more foraging sites. In comparison, when food was scarce the bats had few possibilities to decide where and with whom to forage. Overall, both networks had high mean degree, suggesting communal knowledge of predictable food distribution.

In this paper, a novel principle of contactless gauge block calibration is presented. The principle of contactless gauge block calibration combines low-coherence interferometry and laser interferometry. An experimental setup combines Dowell interferometer and Michelson interferometer to ensure a gauge block length determination with direct traceability to the primary length standard. By monitoring both gauge block sides with a digital camera gauge block 3D surface measurements are possible too. The principle presented is protected by the Czech national patent No. 302948.