Criticality for charged black branes

We show that the inclusion of higher curvature terms in the gravitational action can lead to phase transitions and critical behaviour for charged black branes. The higher curvature terms considered here belong to the recently constructed generalized quasi-topological class [ArXiv: 1703.01631], which possess a number of interesting properties, such as being ghost-free on constant curvature backgrounds and non-trivial in four dimensions. We show that critical behaviour is a generic feature of the black branes in all dimensions $d \ge 4$, and contextualize the results with a review of the properties of black branes in Lovelock and quasi-topological gravity, where critical behaviour is not possible. These results may have interesting implications for the CFTs dual to this class of theories.Comment: 31 pages, 6 figures. v2: minor typos corrected, references added; updated to match published versio

Exposure to polybrominated diphenyl ethers (PBDEs) suppresses the release of pro-inflammatory products by alveolar macrophages in vitro

Endocrine disrupting chemicals have adverse effects on immune function that may result in respiratory conditions. Inhalation of dust is a major route of exposure to PBDEs; however, the impact of PBDEs on the immune response is unclear. The objective of this in vitro study was to determine the impact of PBDEs on the release of pro-inflammatory cytokines by activated alveolar macrophages. Porcine alveolar macrophages were grown in RPMI growth media supplemented with 10% porcine serum and incubated for 24-hours. After 24-hours, cells were activated by inoculation with PMA. In addition to PMA, different concentrations of the PBDE mixture DE-71 were introduced to the wells. After 6-hour incubation, conditioned media was removed and analyzed. Cells exposed to PMA and PBDEs released significantly less pro-inflammatory cytokines compared to controls. Suppression of pro-inflammatory cytokines---characteristic of a compromised immune system---suggests that persistent exposure to PBDEs may increase the susceptibility to respiratory conditions

Reentrant phase transitions and van der Waals behaviour for hairy black holes

We study the extended phase space thermodynamics for hairy AdS black hole solutions to Einstein-Maxwell-$\Lambda$ theory conformally coupled to a scalar field in five dimensions. We find these solutions to exhibit van der Waals behaviour in both the charged/uncharged cases, and reentrant phase transitions in the charged case. This is the first example of reentrant phase transitions in a five dimensional gravitational system which does not include higher curvature corrections.Comment: 11 pages, 5 figures, REVTeX 4-

A study of the adjustment in foster homes of sixteen rejected children placed by the Worcester Children's Friend Society from January, 1947 - July, 1950.

Thesis (M. S.)--Boston Universit

NORSEX 1979 microwave remote sensing data report

Airborne microwave remote sensing measurements obtained by NASA Langley Research Center in support of the 1979 Norwegian Remote Sensing Experiment (NORSEX) are summarized. The objectives of NORSEX were to investigate the capabilities of an active/passive microwave system to measure ice concentration and type in the vicinity of the marginal ice zone near Svalbard, Norway and to apply microwave techniques to the investigation of a thermal oceanic front near Bear Island, Norway. The instruments used during NORSEX include the stepped frequency microwave radiometer, airborne microwave scatterometer, precision radiation thermometer and metric aerial photography. The data are inventoried, summarized, and presented in a user-friendly format. Data summaries are presented as time-history plots which indicate when and where data were obtained as well as the sensor configuration. All data are available on nine-track computer tapes in card-image format upon request to the NASA Langley Technical Library

Hairy black holes in cubic quasi-topological gravity

We construct a class of five dimensional black hole solutions to cubic quasi-topological gravity with conformal scalar hair and study their thermodynamics. We find these black holes provide the second example of black hole $\lambda$-lines: a line of second order (continuous) phase transitions, akin to the fluid/superfluid transition of $^4$He. Examples of isolated critical points are found for spherical black holes, marking the first in the literature to date. We also find various novel and interesting phase structures, including an isolated critical point occurring in conjunction with a double reentrant phase transition. The AdS vacua of the theory are studied, finding ghost-free configurations where the scalar field takes on a non-zero constant value, in notable contrast to the five dimensional Lovelock case.Comment: 29 pages, 12 figure

Thermalon mediated phase transitions in Gauss-Bonnet gravity

Thermalons can mediate phase transitions between different vacua in higher curvature gravity, potentially changing the asymptotic structure of the spacetime. Treating the cosmological constant as a dynamical parameter, we study these phase transitions in the context of extended thermodynamic phase space. We find that in addition to the AdS to dS phase transitions previously studied, thermal AdS space can undergo a phase transition to an asymptotically flat black hole geometry. In the context of AdS to AdS transitions, we comment on the similarities and differences between thermalon transitions and the Hawking-Page transition.Comment: 20 pages, 11 figures; reference added, corrected to match published versio

Thermodynamics of hairy black holes in Lovelock gravity

We perform a thorough study of the thermodynamic properties of a class of Lovelock black holes with conformal scalar hair arising from coupling of a real scalar field to the dimensionally extended Euler densities. We study the linearized equations of motion of the theory and describe constraints under which the theory is free from ghosts/tachyons. We then consider, within the context of black hole chemistry, the thermodynamics of the hairy black holes in the Gauss-Bonnet and cubic Lovelock theories. We clarify the connection between isolated critical points and thermodynamic singularities, finding a one parameter family of these critical points which occur for well-defined thermodynamic parameters. We also report on a number of novel results, including `virtual triple points' and the first example of a `$\lambda$-line'---a line of second order phase transitions---in black hole thermodynamics.Comment: 62 pages, 30 figures. Minor changes and typos corrected. Updated to match published versio