The gravity duals of SO/USp superconformal quivers

We study the gravity duals of SO/USp superconformal quiver gauge theories realized by M5-branes wrapping on a Riemann surface ("G-curve") together with a Z_2-quotient. When the G-curve has no punctures, the gravity solutions are classified by the genus g of the G-curve and the torsion part of the four-form flux G_4. We also find that there is an interesting relation between anomaly contributions from two mysterious theories: T_{SO(2N)} theory with SO(2N)^3 flavor symmetry and \tilde{T}_{SO(2N)} theory with SO(2N) x USp(2N-2)^2 flavor symmetry. The dual gravity solutions for various SO/USp-type tails are also studied.Comment: 27 pages, 13 figures; v2 minor corrections, typos corrected, Figure 13 replaced, references adde

Holographic Entanglement Entropy at Finite Temperature

Using a holographic proposal for the entanglement entropy we study its behavior in various supergravity backgrounds. We are particularly interested in the possibility of using the entanglement entropy as way to detect transitions induced by the presence horizons. We consider several geometries with horizons: the black hole in $AdS_3$, nonextremal Dp-branes, dyonic black holes asymptotically to $AdS_4$ and also Schwarzschild black holes in global $AdS_p$ coordinates. Generically, we find that the entanglement entropy does not exhibit a transition, that is, one of the two possible configurations always dominates.Comment: v3: 31 pp, ten figures, modified to match version accepted by IJMP

Dipole Coupling Effect of Holographic Fermion in the Background of Charged Gauss-Bonnet AdS Black Hole

We investigate the holographic fermions in the charged Gauss-Bonnet $AdS_{d}$ black hole background with the dipole coupling between fermion and gauge field in the bulk. We show that in addition to the strength of the dipole coupling, the spacetime dimension and the higher curvature correction in the gravity background also influence the onset of the Fermi gap and the gap distance. We find that the higher curvature effect modifies the fermion spectral density and influences the value of the Fermi momentum for the appearance of the Fermi surface. There are richer physics in the boundary fermion system due to the modification in the bulk gravity.Comment: 16 pages, accepted for publication in JHE

Obstetric emergencies in the maternity ward of the Ignace Deen national hospital CHU of Conakry: sociodemographic, therapeutic and maternal fetal prognosis aspects

Background: Despite government efforts to reduce maternal mortality, the risk of a woman dying from obstetric complications is about one in six in the poorest regions of the world compared to one in thirty thousand in North Europe. The objective was therefore to describe the clinical socio-demographic aspects and to establish the maternal and fetal prognosis of obstetric emergencies.Methods: This was a descriptive cross-sectional prospective study over a 6-month period from January 1 to June 30, 2020 carried out at the maternity ward of the Ignace Deen national hospital (Conakry university hospital) in Guinea. The study looked at a continuous series of 662 obstetric emergency cases.Results: The frequency of admission of obstetric emergencies was 22.62%. They concerned young women (29.5 years old) on average, first-time mothers (53.32%), with low income professional activities, evacuated from a peripheral maternity unit (63.14%), no schooling (44.9%), married (92.3%), using the more often a means of public transport (66.5%) and whose pregnancies were poorly monitored (63.9%). Fetal emergencies were dominated by acute fetal distress (91.3%) and maternal emergencies were dominated by hypertensive emergencies (pre-eclampsia and eclampsia 37.44%) followed by hemorrhagic emergencies (last trimester hemorrhage and postpartum hemorrhage 34.34%). Pregnant and parturient women were more frequently admitted to labor (62.7%) and gave birth more frequently by caesarean section (86.70%). the staff reacted promptly to make a treatment decision in 75.5% of cases within fifteen minutes. emergency procedures were performed in less than fifteen minutes in almost all cases (97.4%), specific treatment was carried out in less than an hour in the majority of cases (68.3%). The maternal case fatality rate was 4.1% with the main cause of death being hemorrhagic shock of 51.8%. The stillbirth rate was 17.4%.Conclusions: The anticipation of emergency obstetric care (SOU) and close collaboration between the obstetrician, the anesthesiologist-resuscitator are essential in the management of obstetric emergencies

On N = 2 Truncations of IIB on T^{1,1}

We study the N=4 gauged supergravity theory which arises from the consistent truncation of IIB supergravity on the coset T^{1,1}. We analyze three N=2 subsectors and in particular we clarify the relationship between true superpotentials for gauged supergravity and certain fake superpotentials which have been widely used in the literature. We derive a superpotential for the general reduction of type I supergravity on T^{1,1} and this together with a certain solution generating symmetry is tantamount to a superpotential for the baryonic branch of the Klebanov-Strassler solution.Comment: 32 pages, v2:references adde

Prediction of ineffective elective cardioversion of atrial fibrillation: a retrospective multi-center patient cohort study

Background: Elective cardioversion (ECV) of atrial fibrillation (AF) is a standard procedure to restore sinus rhythm. However, predictors for ineffective ECV (failure of ECV or recurrence of AF within 30 days) are unknown.Methods: We investigated 1998 ECVs performed for AF lasting >48 h in 1,342 patients in a retrospective multi-center study. Follow-up data were collected from 30 days after ECV.Results: Median number of cardioversions was one per patient with a range of 1-10. Altogether 303/1998 (15.2%) ECVs failed. Long (>5 years) AF history and over 30 days duration of the index AF episode were independent predictors for ECV failure and low (60/min) ventricular rate, renal failure and antiarrhythmic agents at discharge were the independent predictors for recurrence. In total ECV was ineffective in 852 (42.6%) cases. Female gender (OR 1.44, CI95% 1.15-1.80, p 60/min (OR 1.92, CI95% 1.08-3.41, p = 0.03), antiarrhythmic medication at discharge (OR 1.48, CI95% 1.14-1.93, p < 0.01) and low (<60/ml/min) estimated glomerular filtration rate (OR 1.59, CI95% 1.08-2.33, p = 0.02) were predictors of ineffective ECV.Conclusions: Female gender, use of antiarrhythmic drug therapy and renal failure predicted both recurrence of AF and the composite end point. For the first time in a large real-life study several clinical predictors for clinically ineffective ECV were identified

Disordered Systems and the Replica Method in AdS/CFT

We formulate a holographic description of effects of disorder in conformal field theories based on the replica method and the AdS/CFT correspondence. Starting with $n$ copies of conformal field theories, randomness with a gaussian distribution is described by a deformation of double trace operators. After computing physical quantities, we take the $n \to 0$ limit at the final step. We compute correlation functions in the disordered systems by using the holographic replica method as well as the formulation in the conformal field theory. We find examples where disorder changes drastically the scaling of two point functions. The renormalization group flow of the effective central charge in our disordered systems is also discussed.Comment: 26 pages, references added, published versio