SALT long-slit spectroscopy of LBQS 2113-4538: variability of the Mg II and Fe II component

The Mg II line is of extreme importance in intermediate redshift quasars since it allows us to measure the black hole mass in these sources and to use these sources as probes of the distribution of dark energy in the Universe, as a complementary tool to SN Ia. Reliable use of Mg II requires a good understanding of all the systematic effects involved in the measurement of the line properties, including the contamination by Fe II UV emission. We performed three spectroscopic observations of a quasar LBQS 2113-4538 (z = 0.956) with the SALT telescope separated in time by several months and we analyze in detail the mean spectrum and the variability in the spectral shape. We show that even in our good-quality spectra the Mg II doublet is well fit by a single Lorentzian shape. We tested several models of the Fe II pseudo-continuum and showed that one of them well represents all the data. The amplitudes of both components vary in time, but the shapes do not change significantly. The measured line width of LBQS 2113-4538 identifies this object as a class A quasar. The upper limit of $3\%$ for the contribution of the Narrow Line Region (NLR) to Mg II may suggest that the separation of the Broad Line Region (BLR) and NLR disappears in this class of objects.Comment: 10 pages, 8 figures, accepted to A&

Mixed-mode oscillations in a multiple time scale phantom bursting system

In this work we study mixed mode oscillations in a model of secretion of GnRH (Gonadotropin Releasing Hormone). The model is a phantom burster consisting of two feedforward coupled FitzHugh-Nagumo systems, with three time scales. The forcing system (Regulator) evolves on the slowest scale and acts by moving the slow nullcline of the forced system (Secretor). There are three modes of dynamics: pulsatility (transient relaxation oscillation), surge (quasi steady state) and small oscillations related to the passage of the slow nullcline through a fold point of the fast nullcline. We derive a variety of reductions, taking advantage of the mentioned features of the system. We obtain two results; one on the local dynamics near the fold in the parameter regime corresponding to the presence of small oscillations and the other on the global dynamics, more specifically on the existence of an attracting limit cycle. Our local result is a rigorous characterization of small canards and sectors of rotation in the case of folded node with an additional time scale, a feature allowing for a clear geometric argument. The global result gives the existence of an attracting unique limit cycle, which, in some parameter regimes, remains attracting and unique even during passages through a canard explosion.Comment: 38 pages, 16 figure

Range Expansion of \u3cem\u3eSigmodon hispidus\u3c/em\u3e (Hispid Cotton Rat) Into Reclaimed Coal Surface-Mines in Southeastern Kentucky

Sigmodon hispidus (Hispid Cotton Rat) is the most wide-spread species of Sigmodon in North America. In recent years, this species has expanded northward and westward in the western part of its range due to changes in habitat and climate. Evidence suggests northward expansion is also occurring in Kentucky. Since the 1980s, extensive coal mining via surface mining and mountain-top removal has transformed more than 2300 km2 of hardwood forests on the Cumberland Plateau of eastern Kentucky. Mining has transformed the landscape, once characterized by forests with deep valleys, steep slopes, and narrow, winding ridgetops into reclaimed sites with a relatively flat landscape dominated by grasses and forbs suitable for run-making rodents. Hispid Cotton Rat is thus poised to expand into the reclaimed mines of eastern Kentucky. We report the first record of Hispid Cotton Rat from a reclaimed-mine site and predict this species will expand its range north and east through this new habitat

Racemose neurocysticercosis.

BACKGROUND: Neurocysticercosis (NCC) is an invasive parasitic infection of the central nervous system caused by the larval stage of the tapeworm Taenia solium. The clinical manifestations of NCC depend on the parasitic load and location of infection, as well as the developmental stage of the cysticerci and host immune response, with symptoms ranging from subclinical headaches to seizures, cerebrovascular events, and life-threatening hydrocephalus. Racemose NCC represents a particularly severe variant of extraparenchymal NCC characterized by the presence of multiple confluent cysts within the subarachnoid space and is associated with increased morbidity and mortality, as well as a decreased response to treatment. Albendazole is the preferred drug for the treatment of racemose NCC due to its superior cerebrospinal fluid penetration compared to praziquantel and the ability to be used concomitantly with steroids. CASE DESCRIPTION: In this report, we describe a 39-year-old man recently emigrated from Mexico with racemose NCC and hydrocephalus successfully treated with prolonged albendazole treatment, high-dose dexamethasone, and ventriculoperitoneal shunt placement for the relief of obstructive hydrocephalus. CONCLUSIONS: Treatment of racemose NCC represents a significant clinical challenge requiring multimodal intervention to minimize infectious- and treatment-related morbidity. We review the clinical, diagnostic, and therapeutic features relevant to the management of this aggressive form of NCC

The mass of the black hole in RE J1034+396

The black hole mass measurement in active galaxies is a challenge, particularly in sources where the reverberation method cannot be applied. We aim to determine the black hole mass in a very special object, RE J1034+396, one of the two AGN with QPO oscillations detected in X-rays, and a single bright AGN with optical band totally dominated by starlight. We fit the stellar content using the code starlight, and the broad band disk contribution to optical/UV/X-ray emission is modeled with optxagnf. We also determine the black hole mass using several other independent methods. Various methods give contradictory results. Most measurements of the blacc hole mass are in the range 1.e6-1.e7 Msun, and the measurements based on dynamics give higher values than measurements based on Hbeta and Mg II emission lines.Comment: A&A, in pres

Sedentary death syndrome is what researchers now call America's second largest threat to public health

Press release.Obesity has doubled, Type 2 diabetes has increased nine-fold, and heart disease remains the number one cause of death for Americans. Sedentary Death Syndrome, or "SeDS," is a growing list of health disorders that are exacerbated by lack of physical activity, causing premature disability and death. Sixty percent of all Americans are at risk, including children. SeDS is expected to add as much as $3 trillion to healthcare costs over ten years, more than twice the tax cut passed by the US Senate