Are Dogs Altering Microbial Communities and Contributing to Antibiotic Resistance in Urban Park Soil Bacteria?

Parks and other green spaces are important parts of the urban landscape, providing residents with valuable ecosystem services. Many urban residents visit parks or other types of green space with their dogs on a daily basis, and dog waste is a common problem in these areas. The environmental and health impacts of dogs' left-behind solid waste has been and continues to be studied. However, the impacts of dog urine have received essentially no close attention, and its effects in urban areas are not well understood. Dogs are required to be kept on leashes in public spaces in Finland, and most of their urine has been found to be concentrated along walking paths. Since dogs are commonly treated for infections and other illnesses, these same areas are likely receiving sporadic, low-level doses of antibiotics. This highly localized and chronic deposition of residual antibiotics in areas used for human recreation and leisure represents a uniquely urban phenomenon. In this study we have analysed soil DNA extracts from Helsinki and Lahti greenspaces using SmartChip qPCR Analysis. We found elevated numbers of ARG copies in areas impacted by dog urine versus control sites. Further analysis will be needed to determine the significance of this effect, but the results suggest that dogs are contributing to the development of antibiotic resistance urban park soil bacteria.Non peer reviewe

The Photometric Investigation of V921 Her using the Lunar-based Ultraviolet Telescope of Chang'e-3 mission

The light curve of V921 Her in ultraviolet band observed by the Lunar-based Ultraviolet Telescope (LUT) is analyzed by the Wilson-Devinney code. Our solutions conclude that V921 Her is an early type marginal contact binary system with an additional close-in component. The binary system is under poor thermal contact with a temperature difference of nearly $700K$ between the two components. The close-in component contributes about $19\,\%$ of the total luminosity in the triple system. Combining the radial velocity study together with our photometric solutions, the mass of the primary star and secondary one are calculated to be $M_1 = 1.784(\pm0.055)M_\odot$, $M_2 = 0.403(\pm0.012)M_\odot$. The evolutionary scenario of V921 Her is discussed. All times of light minimum of V921 Her available in the bibliography are taken into account and the $O - C$ curve is analyzed for the first time. The most probable fitting results are discussed in the paper, which also confirm the existence of a third component ($P_3=10.2$ year) around the binary system. The period of V921 Her is also undergoing a continuously rapid increase at a rate of $dP/dt=+2.79\times{10^{-7}}day\cdot year^{-1}$, which may due to mass transfer from the less massive component to the more massive one