Fermion correlators in non-abelian holographic superconductors

We consider fermion correlators in non-abelian holographic superconductors. The spectral function of the fermions exhibits several interesting features such as support in displaced Dirac cones and an asymmetric distribution of normal modes. These features are compared to similar ones observed in angle resolved photoemission experiments on high T_c superconductors. Along the way we elucidate some properties of p-wave superconductors in AdS_4 and discuss the construction of SO(4) superconductors.Comment: 49 pages, 11 figure

Charged black rings in supergravity with a single non-zero gauge field

General charged black ring solution with two angular momenta, a charge and a dipole charge is found by the inverse scattering method. The solution is presented in a relatively concise form in which its symmetries are manifest. The regularity conditions are found and the physical characteristics of the regular solution are expressed via its parameters.Comment: Misprints corrected, references added, JHEP forma

Psychological stress factors and salivary cortisol in nursing students throughout their training

OBJECTIVE: to analyze psychological stress factors and salivary cortisol concentration in nursing undergraduates throughout their training. METHOD: a cross-sectional, analytical, and comparative study carried out in an evening course using a sociodemographic questionnaire, an Instrument to Assess Stress in Nursing Students, and salivary cortisol analysis. The study included descriptive and comparative analyses and a multiple linear regression model. RESULTS: 187 participants answered the questionnaires, and 129 had their cortisol quantified. The domains Practical Activities Execution, Professional Communication, and Professional Training represented the stress factors with the highest mean values for 3rd, 4th, and 5th-year students compared to 1st and 2nd year. For the 5th year, it was the domains Professional Communication and Professional Training compared to the 3rd year and Environment compared to the 1st and 3rd year. A significant result was obtained between the times of cortisol collections for males (p < 0.0001), females (p < 0.0001), and for 1st (p = 0.0319) 2nd (p = 0.0245), and 5th (p < 0.0001) years. CONCLUSION: Students in years 3 through 5 had higher exposure to stressors, and there were adjustments in cortisol production rhythmicity for students in years 1, 2, and 5

Inverse Scattering Construction of a Dipole Black Ring

Using the inverse scattering method in six dimensions we construct the dipole black ring of five dimensional Einstein-Maxwell-dilaton theory with dilaton coupling a = 2(2/3)^(1/2).The 5d theory can be thought of as the NS sector of low energy string theory in Einstein frame. It can also be obtained by dimensionally reducing six-dimensional vacuum gravity on a circle. Our new approach uses GL(4, R) integrability structure of the theory inherited from six-dimensional vacuum gravity. Our approach is also general enough to potentially generate dipole black objects carrying multiple rotations as well as more exotic multi-horizon configurations

Semi-Holographic Fermi Liquids

We show that the universal physics of recent holographic non-Fermi liquid models is captured by a semi-holographic description, in which a dynamical boundary field is coupled to a strongly coupled conformal sector having a gravity dual. This allows various generalizations, such as a dynamical exponent and lattice and impurity effects. We examine possible relevant deformations, including multi-trace terms and spin-orbit effects. We discuss the matching onto the UV theory of the earlier work, and an alternate description in which the boundary field is integrated out.Comment: 26 pages, 4 figures; v2: typos corrected and report number adde

Gravitational energy of a magnetized Schwarzschild black hole - a teleparallel approach

We investigate the distribution of gravitational energy on the spacetime of a Schwarzschild black hole immersed in a cosmic magnetic field. This is done in the context of the {\it Teleparallel Equivalent of General Relativity}, which is an alternative geometrical formulation of General Relativity, where gravity is describe by a spacetime endowed with torsion, rather than curvature, with the fundamental field variables being tetrads. We calculate the energy enclosed by a two-surface of constant radius - in particular, the energy enclosed by the event horizon of the black hole. In this case we find that the magnetic field has the effect of increasing the gravitational energy as compared to the vacuum Schwarzschild case. We also compute the energy (i) in the weak magnetic field limit, (ii) in the limit of vanishing magnetic field, and (iii) in the absence of the black hole. In all cases our results are consistent with what should be expected on physical grounds.Comment: version to match the one to be published on General Relativity and Gravitatio

Linearized stability analysis of gravastars in noncommutative geometry

In this work, we find exact gravastar solutions in the context of noncommutative geometry, and explore their physical properties and characteristics. The energy density of these geometries is a smeared and particle-like gravitational source, where the mass is diffused throughout a region of linear dimension $\sqrt{(\alpha)}$ due to the intrinsic uncertainty encoded in the coordinate commutator. These solutions are then matched to an exterior Schwarzschild spacetime. We further explore the dynamical stability of the transition layer of these gravastars, for the specific case of $\beta=M^2/\alpha<1.9$, where M is the black hole mass, to linearized spherically symmetric radial perturbations about static equilibrium solutions. It is found that large stability regions exist and, in particular, located sufficiently close to where the event horizon is expected to form.Comment: 6 pages, 3 figure

Sialic Acid Glycobiology Unveils Trypanosoma cruzi Trypomastigote Membrane Physiology.

Trypanosoma cruzi, the flagellate protozoan agent of Chagas disease or American trypanosomiasis, is unable to synthesize sialic acids de novo. Mucins and trans-sialidase (TS) are substrate and enzyme, respectively, of the glycobiological system that scavenges sialic acid from the host in a crucial interplay for T. cruzi life cycle. The acquisition of the sialyl residue allows the parasite to avoid lysis by serum factors and to interact with the host cell. A major drawback to studying the sialylation kinetics and turnover of the trypomastigote glycoconjugates is the difficulty to identify and follow the recently acquired sialyl residues. To tackle this issue, we followed an unnatural sugar approach as bioorthogonal chemical reporters, where the use of azidosialyl residues allowed identifying the acquired sugar. Advanced microscopy techniques, together with biochemical methods, were used to study the trypomastigote membrane from its glycobiological perspective. Main sialyl acceptors were identified as mucins by biochemical procedures and protein markers. Together with determining their shedding and turnover rates, we also report that several membrane proteins, including TS and its substrates, both glycosylphosphatidylinositol-anchored proteins, are separately distributed on parasite surface and contained in different and highly stable membrane microdomains. Notably, labeling for α(1,3)Galactosyl residues only partially colocalize with sialylated mucins, indicating that two species of glycosylated mucins do exist, which are segregated at the parasite surface. Moreover, sialylated mucins were included in lipid-raft-domains, whereas TS molecules are not. The location of the surface-anchored TS resulted too far off as to be capable to sialylate mucins, a role played by the shed TS instead. Phosphatidylinositol-phospholipase-C activity is actually not present in trypomastigotes. Therefore, shedding of TS occurs via microvesicles instead of as a fully soluble form

Neuroinflammation and structural injury of the fetal ovine brain following intra-amniotic Candida albicans exposure.

BackgroundIntra-amniotic Candida albicans (C. Albicans) infection is associated with preterm birth and high morbidity and mortality rates. Survivors are prone to adverse neurodevelopmental outcomes. The mechanisms leading to these adverse neonatal brain outcomes remain largely unknown. To better understand the mechanisms underlying C. albicans-induced fetal brain injury, we studied immunological responses and structural changes of the fetal brain in a well-established translational ovine model of intra-amniotic C. albicans infection. In addition, we tested whether these potential adverse outcomes of the fetal brain were improved in utero by antifungal treatment with fluconazole.MethodsPregnant ewes received an intra-amniotic injection of 10(7) colony-forming units C. albicans or saline (controls) at 3 or 5 days before preterm delivery at 0.8 of gestation (term ~ 150 days). Fetal intra-amniotic/intra-peritoneal injections of fluconazole or saline (controls) were administered 2 days after C. albicans exposure. Post mortem analyses for fungal burden, peripheral immune activation, neuroinflammation, and white matter/neuronal injury were performed to determine the effects of intra-amniotic C. albicans and fluconazole treatment.ResultsIntra-amniotic exposure to C. albicans caused a severe systemic inflammatory response, illustrated by a robust increase of plasma interleukin-6 concentrations. Cerebrospinal fluid cultures were positive for C. albicans in the majority of the 3-day C. albicans-exposed animals whereas no positive cultures were present in the 5-day C. albicans-exposed and fluconazole-treated animals. Although C. albicans was not detected in the brain parenchyma, a neuroinflammatory response in the hippocampus and white matter was seen which was characterized by increased microglial and astrocyte activation. These neuroinflammatory changes were accompanied by structural white matter injury. Intra-amniotic fluconazole reduced fetal mortality but did not attenuate neuroinflammation and white matter injury.ConclusionsIntra-amniotic C. albicans exposure provoked acute systemic and neuroinflammatory responses with concomitant white matter injury. Fluconazole treatment prevented systemic inflammation without attenuating cerebral inflammation and injury

An electrically charged doubly spinning dipole black ring

We present a new asymptotically flat, doubly spinning black ring of D = 5 Einstein-Maxwell-dilaton theory with Kaluza-Klein dilaton coupling. Besides the mass and two angular momenta, the solution displays both electric charge and (magnetic) dipole charge. The class of solutions that are free from conical singularities is described by four parameters. We first derive the solution in six dimensions employing the inverse scattering method, thereby generalising the inverse-scattering construction by two of the current authors of Emparan's singly spinning dipole black ring. The novel black ring itself arises upon circle Kaluza-Klein reduction. We also compute the main physical properties and asymptotic charges of our new class of solutions. Finally, we present a five-parameter generalisation of our solution.Comment: v2: Improved presentation with new additions including plots of some physical charges and a new appendix with the most general five-parameter solution. Version to be published in JHE