Accretion disk coronae of Intermediate Polar Cataclysmic Variables - 3D MagnetoHydro-Dynamic modeling and thermal X-ray emission

IPCVs contain a magnetic, rotating white dwarf surrounded by a magnetically truncated accretion disk. To explain their strong flickering X-ray emission, accretion has been successfully taken into account. Nevertheless, observations suggest that accretion phenomena could not be the only process behind it. An intense flaring activity occurring on the surface of the disk may generate a corona, contribute to the thermal X-ray emission and influence the system stability. Our purposes are: investigating the formation of an extended corona above the accretion disk, due to an intense flaring activity occurring on the disk surface; studying its effects on the disk and stellar magnetosphere; assessing its contribution to the observed X-ray flux. We have developed a 3D MHD model of a IPCV. The model takes into account gravity, disk viscosity, thermal conduction, radiative losses and coronal flare heating. To perform a parameter space exploration, several system conditions have been considered, with different magnetic field intensity and disk density values. From the results of the evolution of the model, we have synthesized the thermal X-ray emission. The simulations show the formation of an extended corona, linking disk and star. The flaring activity is capable of strongly influencing the disk configuration and its stability, effectively deforming the magnetic field lines. Hot plasma evaporation phenomena occur in the layer immediately above the disk. The flaring activity gives rise to a thermal X-ray emission in both the [0.1-2.0] keV and the [2.0-10] keV bands. An intense coronal activity occurring on the disk surface of an IPCV can affect the structure of the disk depending noticeably on the density of the disk and the magnetic field of the central object. Moreover, the synthesis of the thermal X-ray fluxes shows that this flaring activity may contribute to the observed thermal X-ray emission

Cocaine contamination in pubic hair: Analysis of the decontamination method

Abstract Even if pubic hair represents a reliable and widely accepted alternative hair matrix to identify drug abusers, it might produce false positive results due to external contamination. The aim of this study was to verify whether the external contamination of pubic hair with cocaine could influence the discrimination between active users and false positive subjects. The analysis was performed on in vivo and in vitro samples; the contamination was carried out by rubbing pubic hair with cocaine hydrochloride contaminated hands for three consecutive days. Five days after the beginning of the contamination, the pubic hair was collected and analysed at different times for two months. Data from our studies show that all in vivo samples yielded false positives; the in vitro samples were negative only for 10 days and then yielded false positives

Effect of an automatic feeding system on growth performance and feeding behaviour of pigs reared outdoors

Nine Mora Romagnola and 10 Large White x Mora Romagnola growing pigs were reared outdoors. In both groups ad libitum feed was provided. Conventional pigs received it twice a day, distributed in two long troughs. Inside the corral of the second group, an automatic station was set up for: feed distribution, pigs weighing, and control by an analog camera. Thus the self-feeders received feed ad libitum individually by the automatic system, divided into small quantities at meal times. During the experiment the analog camera was used over 24 hours each day, to collect pictures of pigs in order to investigate their behaviours. For each picture the day and hour, the number of visible pigs and their behaviours were recorded and a statistical analysis of data, which was expressed as hourly frequencies of behavioural elements, was performed. Moreover to highlight "active" and "passive" behaviours between the groups, two categories "Move" and "Rest" were created grouping some behavioural elements. With regard to performance, conventional pigs reached a higher total weight gain (56.1±2.42 kg vs 46.7±2.42 kg; P=0.0117). But the feed conversion index (FCI) of both groups was similar. The self-feeders had consumed less feed than conventional animals. The feeding system seems to influence behaviours. The percentage of time spent in Eating activity differs (P<0.0001) between the self-fed (median 24.6%) and conventional pigs (median 10.9%). The resulting more regular eating trend of self-feeders influenced the daily activities distribution. The behavioural category Rest (median: self-feeders 55.0% vs 71.4% conventional pigs) was dominant, with conventional pigs becoming more restless, particularly at meal times. This type of feeding competition and aggressive behaviour did not happen in the self-feeders due to the feed distribution system. The self-feeder results showed that pigs eat at the automatic station both day and night. The animals perform on average 3 visits per hour at night and 10 during the day, with an average duration of some minutes (from 3 to 5 approximately)