Amplitude Modulation in the ZZ Ceti Star GD 244

Previous studies of GD 244 revealed seven pulsation frequencies (two doublets and three single periods) in the light variations of the star. The data obtained at McDonald Observatory between 2003 and 2006, and our additional measurements in 2006 and 2007 at Konkoly Observatory, allow the investigation of the long-term pulsational behaviour of GD 244. We found that the 307.1 s period component of one of the doublets show long-term, periodic amplitude modulation with a time scale of ~740 days. Possible explanations are that nonlinear resonant mode coupling is operating among the rotationally split frequency components, or two modes, unresolved in the yearly data are excited at ~307.1 s. This is the first time that such long-term periodic amplitude modulation is published on a ZZ Ceti star.Comment: 4 pages, 2 figures, appeared in ASP Conference Series vol. 493, 2015 (eds.: P. Dufour, P. Bergeron, G. Fontaine, 19th European Workshop on White Dwarfs, Montreal, Canada

Forecasting share price movements using news sentiment analysis in a multinational environment

Using a common definition we can define news analysis as the measurement of the various qualitative and quantitative elements of textual news stories. These elements include sentiment, relevance and novelty. By quantifying news stories we can gain a useful way to manipulate and use everyday information in a mathematically concise manner. In this article a framework for news analytics techniques used in finance is provided. Various news analytic methods and software are discussed, and a set of metrics is given that may be applied to assess the performance of analytics. Various directions for this field are discussed. The proposed methods can help the valuation and trading of securities, facilitate investment decision making, meet regulatory requirements, or manage risk

Delineation of the Pannonian vegetation region

Phytogeographical regions have been set up traditionally on the basis of the flora. Several examples indicate that the potential natural vegetation is also suitable for this purpose although the flora- and vegetation-based boundaries do not necessarily overlap. We define a vegetation region as an area where the physical geographic features are rather uniform, and which consists of landscapes with floristically/structurally similar vegetation and/or their repetitive mosaics. In this paper, we delimited the boundaries of the Pannonian region based on the distribution of characteristic plant communities. The line runs most often on the border between Quercus cerris-Quercus petraea and Carpinus betulus/Fagus sylvatica dominated landscapes. We provided descriptions of the potential vegetation on both sides of the boundary. The region has an area of 167,012 km2. The region is either in direct contact with the neighboring regions (e.g., Western Carpathians), or is separated from them by transitional areas (towards the Eastern Alps), and character-poor areas with non-Pannonian, non-Alpine, non-Dinaric vegetation (in the southwest to the Western Balkan). Often, the boundary does not coincide with the boundary of the Pannonicum floristic province. We found that vegetation region boundaries can help reevaluate long-established floristic region boundaries. The boundary of the ’floristic Pannonian region’ also requires revision based on integrated distribution databases and statistical analyses. We argue that the method applied here is simple, repeatable and falsifiable. Our map provides an opportunity to the European Union to use a scientifically more sound biogeographical circumscription of the Pannonian region in her Natura 2000 and other programs

G 207-9 and LP 133-144: light curve analysis and asteroseismology of two ZZ Ceti stars

G 207-9 and LP 133-144 are two rarely observed ZZ Ceti stars located in the middle and close to the blue edge of the ZZ Ceti instability domain, respectively. We aimed to observe them at least during one observing season at Konkoly Observatory with the purpose of extending the list of known pulsation modes for asteroseismic investigations and detect any significant changes in their pulsational behaviour. We determined five and three new normal modes of G 207-9 and LP 133-144, respectively. In LP 133-144, our frequency analysis also revealed that at least at three modes there are actually triplets with frequency separations of ~4 microHz. The rotational period of LP 133-144 based on the triplets is ~42 h. The preliminary asteroseismic fits of G 207-9 predict Teff=12 000 or 12 400 K and M*=0.855-0.870 MSun values for the effective temperature and mass of the star, depending on the assumptions on the spherical degree (l) values of the modes. These results are in agreement with the spectroscopic determinations. In the case of LP 133-144, the best-fitting models prefer Teff=11 800 K in effective temperature and M*>=0.71 MSun stellar masses, which are more than 0.1 MSun larger than the spectroscopic value.Comment: 12 pages, 11 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society (2016 June 30