The Bulge Radial Velocity Assay (BRAVA): I. Techniques and a Rotation Curve

We are undertaking a large scale radial velocity survey of the Galactic bulge which uses M giant stars selected from the 2MASS catalog as targets for the CTIO 4m Hydra multi-object spectrograph. The aim of this survey is to test dynamical models of the bulge and to quantify the importance, if any, of cold stellar streams in the bulge and its vicinity. Here we report on the kinematics of a strip of fields at -10 < l <+10 degres and b=-4 degres. We construct a longitude-velocity plot for the bulge stars and the model data, and find that contrary to previous studies, the bulge does not rotate as a solid body. From -5<l<+5 degrees the rotation curve has a slope of roughly 100 km/s/kpc and flattens considerably at greater l and reaches a maximum rotation of 45 km/s. We compare our rotation curve and velocity dispersion profile to both the self-consistent model of Zhao (1996) and to N-body models; neither fits both our observed rotation curve and velocity dispersion profile. The high precision of our radial velocities (3 km/s) yields an unexpected result: hints of cold kinematic features are seen in a number of the line of sight velocity distributions.Comment: Accepted to ApJ letters. This replacement updates the paper to the accepted versio

The Bulge Radial Velocity Assay (BRAVA): I. Techniques and a Rotation Curve

We are undertaking a large scale radial velocity survey of the Galactic bulge which uses M giant stars selected from the 2MASS catalog as targets for the CTIO 4m Hydra multi-object spectrograph. The aim of this survey is to test dynamical models of the bulge and to quantify the importance, if any, of cold stellar streams in the bulge and its vicinity. Here we report on the kinematics of a strip of fields at -10 < l <+10 degres and b=-4 degres. We construct a longitude-velocity plot for the bulge stars and the model data, and find that contrary to previous studies, the bulge does not rotate as a solid body. From -5<l<+5 degrees the rotation curve has a slope of roughly 100 km/s/kpc and flattens considerably at greater l and reaches a maximum rotation of 45 km/s. We compare our rotation curve and velocity dispersion profile to both the self-consistent model of Zhao (1996) and to N-body models; neither fits both our observed rotation curve and velocity dispersion profile. The high precision of our radial velocities (3 km/s) yields an unexpected result: hints of cold kinematic features are seen in a number of the line of sight velocity distributions.Comment: Accepted to ApJ letters. This replacement updates the paper to the accepted versio

Light hadron and diquark spectroscopy in quenched QCD with overlap quarks on a large lattice

A simulation of quenched QCD with the overlap Dirac operator has been completed using 100 Wilson gauge configurations at beta = 6 on an 18^3 x 64 lattice and at beta = 5.85 on a 14^3 x 48 lattice, both in Landau gauge. We present results for light meson and baryon masses, meson final state "wave functions," and other observables, as well as some details on the numerical techniques that were used. Our results indicate that scaling violations, if any, are small. We also present an analysis of diquark correlations using the quark propagators generated in our simulation.Comment: 28 LaTeX pages, 41 figures, v2: minor updates, version published in JHE

Experimental and Modeling Investigation of the Effectof H2S Addition to Methane on the Ignition and Oxidation at High Pressures

The autoignition and oxidation behavior of CH₄/H₂S mixtures has been studied experimentally in a rapid compression machine (RCM) and a high-pressure flow reactor. The RCM measurements show that the addition of 1% H₂S to methane reduces the autoignition delay time by a factor of 2 at pressures ranging from 30 to 80 bar and temperatures from 930 to 1050 K. The flow reactor experiments performed at 50 bar show that, for stoichiometric conditions, a large fraction of H₂S is already consumed at 600 K, while temperatures above 750 K are needed to oxidize 10% methane. A detailed chemical kinetic model has been established, describing the oxidation of CH₄ and H₂S as well as the formation and consumption of organosulfuric species. Computations with the model show good agreement with the ignition measurements, provided that reactions of H₂S and SH with peroxides (HO₂ and CH₃OO) are constrained. A comparison of the flow reactor data to modeling predictions shows satisfactory agreement under stoichiometric conditions, while at very reducing conditions, the model underestimates the consumption of both H₂S and CH₄. Similar to the RCM experiments, the presence of H₂S is predicted to promote oxidation of methane. Analysis of the calculations indicates a significant interaction between the oxidation chemistry of H₂S and CH₄, but this chemistry is not well understood at present. More work is desirable on the reactions of H₂S and SH with peroxides (HO₂ and CH₃OO) and the formation and consumption of organosulfuric compounds

Ketamine's antidepressant effect is mediated by energy metabolism and antioxidant defense system.

Fewer than 50% of all patients with major depressive disorder (MDD) treated with currently available antidepressants (ADs) show full remission. Moreover, about one third of the patients suffering from MDD does not respond to conventional ADs and develop treatment-resistant depression (TRD). Ketamine, a non-competitive, voltage-dependent N-Methyl-D-aspartate receptor (NMDAR) antagonist, has been shown to have a rapid antidepressant effect, especially in patients suffering from TRD. Hippocampi of ketamine-treated mice were analysed by metabolome and proteome profiling to delineate ketamine treatment-affected molecular pathways and biosignatures. Our data implicate mitochondrial energy metabolism and the antioxidant defense system as downstream effectors of the ketamine response. Specifically, ketamine tended to downregulate the adenosine triphosphate (ATP)/adenosine diphosphate (ADP) metabolite ratio which strongly correlated with forced swim test (FST) floating time. Furthermore, we found increased levels of enzymes that are part of the 'oxidative phosphorylation' (OXPHOS) pathway. Our study also suggests that ketamine causes less protein damage by rapidly decreasing reactive oxygen species (ROS) production and lend further support to the hypothesis that mitochondria have a critical role for mediating antidepressant action including the rapid ketamine response

Clinicians' caseload management behaviours as explanatory factors in patients' length of time on caseloads : a predictive multilevel study in paediatric community occupational therapy

Peer reviewedPublisher PD

Retired A Stars and Their Companions: Eighteen New Jovian Planets

We report the detection of eighteen Jovian planets discovered as part of our Doppler survey of subgiant stars at Keck Observatory, with follow-up Doppler and photometric observations made at McDonald and Fairborn Observatories, respectively. The host stars have masses 0.927 < Mstar /Msun < 1.95, radii 2.5 < Rstar/Rsun < 8.7, and metallicities -0.46 < [Fe/H] < +0.30. The planets have minimum masses 0.9 MJup 0.76 AU. These detections represent a 50% increase in the number of planets known to orbit stars more massive than 1.5 Msun and provide valuable additional information about the properties of planets around stars more massive thantheSun.Comment: ApJS accepted. The \rotate command prevented proper compilation. As a result Tables 19 and 21 do not fit onto the page, causing the final columns (S_HK, Nobs, respectively) to be omitte

Two Small Temperate Planets Transiting Nearby M Dwarfs in K2 Campaigns 0 and 1

The prime Kepler mission revealed that small planets (<4 R_⊕) are common, especially around low-mass M dwarfs. K2, the repurposed Kepler mission, continues this exploration of small planets around small stars. Here we combine K2 photometry with spectroscopy, adaptive optics imaging, and archival survey images to analyze two small planets orbiting the nearby field-age M dwarfs, K2-26 (EPIC 202083828) and K2-9. K2-26 is an M 1.0 ± 0.5 dwarf at 93 ± 7 pc from K2 Campaign 0. We validate its planet with a day period of 14.5665 and estimate a radius of 2.67_(-0.42)^(+0.46)R_⊕. K2-9 is an M2.5 ± 0.5 dwarf at 110 ± 12 pc from K2 Campaign 1. K2-9b was first identified by Montet et al.; here we present spectra and adaptive optics imaging of the host star and independently validate and characterize the planet. Our analyses indicate K2-9b is a 2.25_(-0.96)^(+0.53)R_⊕ planet with a 18.4498 day period. K2-26b exhibits a transit duration that is too long to be consistent with a circular orbit given its measured stellar radius. Thus, the long transits are likely due to the photoeccentric effect and our transit fits hint at an eccentric orbit. Both planets receive low incident flux from their host stars and have estimated equilibrium temperatures <500 K. K2-9b may receive approximately Earth-like insolation. However, its host star exhibits strong GALEX UV emission which could affect any atmosphere it harbors. K2-26b and K2-9b are representatives of a poorly studied class of small planets with cool temperatures that have radii intermediate to Earth and Neptune. Future study of these systems can provide key insight into trends in bulk composition and atmospheric properties at the transition from silicate dominated to volatile rich bodies

HD 172555: Detection of 63 μ m [OI] emission in a debris disc

Astronomy and Astrophysics 546 (2012): L8 Reproduced with permission from Astronomy & AstrophysicsContext. HD 172555 is a young A7 star belonging to the β Pictoris moving group that harbours a debris disc. The Spitzer/IRS spectrum of the source showed mid-IR features such as silicates and glassy silica species, indicating the presence of a warm dust component with small grains, which places HD 172555 among the small group of debris discs with such properties. The IRS spectrum also shows a possible emission of SiO gas. Aims. We aim to study the dust distribution in the circumstellar disc of HD 172555 and to asses the presence of gas in the debris disc. Methods. As part of the GASPS open time key programme, we obtained Herschel/PACS photometric and spectroscopic observations of the source.We analysed PACS observations of HD 172555 and modelled the spectral energy distribution with a modified blackbody and the gas emission with a two-level population model with no collisional de-excitation. Results. We report for the first time the detection of [OI] atomic gas emission at 63.18 μm in the HD 172555 circumstellar disc. We detect excesses due to circumstellar dust toward HD 172555 in the three photometric bands of PACS (70, 100, and 160 μm).We derive a large dust particle mass of (4.8 ± 0.6) × 10−4 M⊕ and an atomic oxygen mass of 2.5 × 10−2R2 M⊕, where R in AU is the separation between the star and the inner disc. Thus, most of the detected mass of the disc is in the gaseous phaseThis research has been funded by Spanish grants AYA 2010-21161-C02-02, CDS2006-00070 and PRICIT-S2009/ESP-1496. J.-C. Augereau and J. Lebreton thank the ANR (contract ANR-2010 BLAN-0505-01, EXOZODI) and the CNES-PNP for financial support. C. Pinte, F. Menard and W.-F. Thi acknowledges funding from the EU FP7-2011 under Grant Agreement nr. 284405. G. Meeus is supported by RYC-2011-07920. G. Meeus, C. Eiroa, I. Mendigutía and B. Montesinos are partly supported by AYA-2011-26202. F.M. acknowledges support from the Millennium Science Initiative (Chilean Ministry of Economy), through grant ÒNucleus P10-022-F