An XMM-Newton look at the strongly variable radio-weak BL Lac Fermi J1544-0639

Fermi J1544-0639/ASASSN-17gs/AT2017egv was identified as a gamma-ray/optical transient on May 15, 2017. Subsequent multiwavelength observations suggest that this source may belong to the new class of radio-weak BL Lacs. We studied the X-ray spectral properties and short-term variability of Fermi J1544-0639 to constrain the X-ray continuum emission mechanism of this peculiar source. We present the analysis of an XMM-Newton observation, 56 ks in length, performed on February 21, 2018. The source exhibits strong X-ray variability, both in flux and spectral shape, on timescales of ~10 ks, with a harder-when-brighter behaviour typical of BL Lacs. The X-ray spectrum is nicely described by a variable broken power law, with a break energy of around 2.7 keV consistent with radiative cooling due to Comptonization of broad-line region photons. We find evidence for a `soft excess', nicely described by a blackbody with a temperature of ~0.2 keV, consistent with being produced by bulk Comptonization along the jet.Comment: 11 pages, 12 figures. Accepted for publication in Astronomy & Astrophysic

INTEGRAL high energy behaviour of 4U 1812-12

The low mass X-ray binary system 4U 1812-12 was monitored with the INTEGRAL observatory in the period 2003-2004 and with BeppoSAX on April 20, 2000. We report here on the spectral and temporal analysis of both persistent and burst emission. The full data set confirms the persistent nature of this burster, and reveals the presence of emission up to 200 keV. The persistent spectrum is well described by a comptonization (CompTT) model plus a soft blackbody component. The source was observed in a hard spectral state with a 1-200 keV luminosity of 2*10^(36) ergs/s and L/LEdd~1% and no meaningful flux variation has been revealed, as also confirmed by a 2004 RXTE observation. We have also detected 4 bursts showing double peaked profiles and blackbody spectra with temperatures ranging from 1.9 to 3.1 keV.Comment: 6 pages, 4 figures. Accepted for publication by A&

Serum protein electrophoresis pro le during late pregnancy and early post partum period in mares

The aim of the study was to determine how the physiological adjustments occurring during late pregnancy and the early post partum period affect mares’ serum protein profile. Ten pregnant mares (Group A) were monitored from the 34th week of pregnancy until the 3rd week after foaling, ten nonpregnant mares (Group B) were used as the control. Blood samples were collected every 3 weeks, from -16 to -4 weeks preceding parturition, and then every week until the 3rd week after foaling. Additional blood samples were taken within 24±12 h from foaling. The statistical analysis revealed a significant increase in albumin and α2-globulin concentrations obtained from Group A during the experimental period. Dunnet’s test also revealed significantly higher concentrations of α1-globulins, α2-globulins and γ-globulins in group A than in group B. The following results showed that the serum proteins differed in periparturient mares when compared to non-pregnant mares and significant changes in some protein fractions occurred over the experimental period. Focusing on the peripartum period, our study provides specific information about mare’s serum protein profile that could help equine practitioners to better interpret clinical data and promptly diagnose pathological conditions that might compromise the health status of the mare and, as consequence, also her foal

Increase in erythrocyte osmotic resistance following polyunsaturated fatty acids (PUFA) supplementation in show jumper horses

Osmotic fragility test has been used to study the influence of different factors on the osmotic properties of cell membranes. Considering the importance of polyunsaturated fatty acids (PUFA) in biological functions we aimed to investigate the effects of dietary PUFA supplementation on erythrocyte osmotic fragility (EOF), blood lactate (BL), hematocrit (Hct), red blood cell (RBC), hemoglobin (Hb), and mean cell volume (MCV) in 10 jumper horses. Two events occurred prior to start supplementing horse's diet and two events occurred after 4 weeks PUFA supplementation. Five horses received the PUFA supplementation (Group A), and five served as controls (Group B). Blood samples were taken before and after each course. The statistical analysis revealed significant increase in BL, Hct, RBC and Hb following exercise (P<0.0001). However, the interaction between exercise and PUFA supplementation (P=0.0083) showed PUFA-supplemented horses having a smaller rise in BL levels (P=0.0107) following exercise. Significant interactions between exercise and PUFA treatment were also found on EOF levels (P<0.05). The hemolysis curves showed PUFA-supplemented horses exhibiting a reduction in EOF compared to controls (P<0.05). Although hemolysis never occurred at 0.9% NaCl concentration, jumping exercise determined an increase in EOF (P=0.0014) at 0.8% NaCl solution. A significant interaction between exercise and PUFA treatment (P=0.0022) was found showing PUFA-supplemented horses having lower EOF (P=0.0015) following exercise. The assessment of EOF is a suitable indicator of athletic performance. The results showed that PUFA supplementation might exert beneficial effects on the horse body system by enhancing the performance in high-level show jumpers

FERMI transient J1544-0649: a flaring radio-weak BL Lac

On May 15th, 2017, the \emph{FERMI}/LAT gamma-ray telescope observed a transient source not present in any previous high-energy catalogue: J1544-0649. It was visible for two consecutive weeks, with a flux peak on May 21st. Subsequently observed by a \emph{Swift}/XRT follow-up starting on May 26, the X-ray counterpart position was coincident with the optical transient ASASSN-17gs = AT2017egv, detected on May 25, with a potential host galaxy at $z$=0.171. We conducted a 4-months follow-up in radio (Effelsberg-100m) and optical (San Pedro M\'artir, 2.1m) bands, in order to build the overall Spectral Energy Distribution (SED) of this object. The radio data from 5 to 15 GHz confirmed the flat spectrum of the source, favoring a line of sight close to jet axis, not showing significant variability in the explored post-burst time-window. The Rx ratio, common indicator of radio loudness, gives a value at the border between the radio-loud and radio-quiet AGN populations. The Ca$_{\rm{II}}$ H\&K break value (0.29$\pm$0.05) is compatible with the range expected for the long-sought intermediate population between BL Lacs and FRI radio galaxies. An overall SED fitting from Radio to $\gamma$-ray band shows properties typical of a low-power BL Lac. As a whole, these results suggest that this transient could well be a new example of the recently discovered class of radio-weak BL Lac, showing for the first time a flare in the gamma/X-ray bands.Comment: Accepted for publication in ApJ Letter