The Discovery of Gas-Rich, Dusty Starbursts in Luminous Reddened Quasars at z∼2.5z\sim2.5 with ALMA

We present ALMA observations of cold dust and molecular gas in four high-luminosity, heavily reddened (A$_{\rm{V}} \sim 2.5-6$ mag) Type 1 quasars at $z\sim2.5$ with virial M$_{\rm{BH}} \sim 10^{10}$M$_\odot$, to test whether dusty, massive quasars represent the evolutionary link between submillimetre bright galaxies (SMGs) and unobscured quasars. All four quasars are detected in both the dust continuum and in the $^{12}$CO(3-2) line. The mean dust mass is 6$\times$10$^{8}$M$_\odot$ assuming a typical high redshift quasar spectral energy distribution (T=41K, $\beta$=1.95 or T=47K, $\beta$=1.6). The implied star formation rates are very high - $\gtrsim$1000 M$_\odot$ yr$^{-1}$ in all cases. Gas masses estimated from the CO line luminosities cover $\sim$1-5$\times10^{10}$($\alpha_{\rm{CO}} / 0.8$)M$_\odot$ and the gas depletion timescales are very short - $\sim5-20$Myr. A range of gas-to-dust ratios is observed in the sample. We resolve the molecular gas in one quasar - ULASJ2315$+$0143 ($z=2.561$) - which shows a strong velocity gradient over $\sim$20 kpc. The velocity field is consistent with a rotationally supported gas disk but other scenarios, e.g. mergers, cannot be ruled out at the current resolution of these data. In another quasar - ULASJ1234+0907 ($z=2.503$) - we detected molecular line emission from two millimetre bright galaxies within 200 kpc of the quasar, suggesting that this quasar resides in a significant over-density. The high detection rate of both cold dust and molecular gas in these sources, suggests that reddened quasars could correspond to an early phase in massive galaxy formation associated with large gas reservoirs and significant star formation.MB acknowledges funding from the UK Science and Technology Facilities Council (STFC) via an Ernest Rutherford Fellowship. GJ is grateful for support from NRAO through the Grote Reber Doctoral Fellowship Program. RGM and PCH acknowledge funding from STFC via the Institute of Astronomy, Cambridge Consolidated Grant. SA-Z acknowledges support from Peterhouse, Cambridge

Free cortisol index as a surrogate marker for serum free cortisol

Abstract Background The biologically active component of a hormone is the unbound or free fraction. Changes in cortisol-binding protein could give misleading results if only total cortisol is measured for the interpretation of dynamic function tests

The discovery of gas-rich, dusty starbursts in luminous reddened quasars at z ∼ 2.5 with ALMA

We present ALMA observations of cold dust and molecular gas in four high-luminosity, heavily reddened (AV ∼ 2.5-6 mag) type 1 quasars at z ∼ 2.5 with virial MBH ∼ 1010 M⊙, to test whether dusty, massive quasars represent the evolutionary link between submillimetre-bright galaxies and unobscured quasars. All four quasars are detected in both the dust continuum and in the 12CO(3-2) line. The mean dust mass is 6 × 108 M⊙ assuming a typical high-redshift quasar spectral energy distribution (T = 41 K, β = 1.95 or T = 47 K, β = 1.6). The implied star formation rates are very high - ≳1000 M⊙ yr-1 in all cases. Gas masses estimated from the CO line luminosities cover ∼1-5× 1010(αCO/0.8)M⊙ and the gas depletion time-scales are very short - ∼5-20 Myr. A range of gas-to-dust ratios is observed in the sample. We resolve the molecular gas in one quasar - ULASJ2315+0143 (z = 2.561) - which shows a strong velocity gradient over ∼20 kpc. The velocity field is consistent with a rotationally supported gas disc but other scenarios, e.g. mergers, cannot be ruled out at the current resolution of these data. In another quasar - ULASJ1234+0907 (z = 2.503) - we detected molecular line emission from two millimetre-bright galaxies within 200 kpc of the quasar, suggesting that this quasar resides in a significant overdensity. The high detection rate of both cold dust and molecular gas in these sources, suggests that reddened quasars could correspond to an early phase in massive galaxy formation associated with large gas reservoirs and significant star formation

The properties of (sub)millimetre-selected galaxies as revealed by CANDELS HST WFC3/IR imaging in GOODS-South

We have exploited the HST CANDELS WFC3/IR imaging to study the properties of (sub-)mm galaxies in GOODS-South. After using the deep radio and Spitzer imaging to identify galaxy counterparts for the (sub-)mm sources, we have used the new CANDELS data in two ways. First, we have derived improved photometric redshifts and stellar masses, confirming that the (sub-)mm galaxies are massive (=2.2x10^11 M_solar) galaxies at z=1-3. Second, we have exploited the depth and resolution of the WFC3/IR imaging to determine the sizes and morphologies of the galaxies at rest-frame optical wavelengths, fitting two-dimensional axi-symmetric Sersic models. Crucially, the WFC3/IR H-band imaging enables modelling of the mass-dominant galaxy, rather than the blue high-surface brightness features which often dominate optical (rest-frame UV) images of (sub-)mm galaxies, and can confuse visual morphological classification. As a result of this analysis we find that >95% of the rest-frame optical light in almost all of the (sub-)mm galaxies is well-described by either a single exponential disk, or a multiple-component system in which the dominant constituent is disk-like. We demonstrate that this conclusion is consistent with the results of high-quality ground-based K-band imaging, and explain why. The massive disk galaxies which host luminous (sub-)mm emission are reasonably extended (r_e=4 kpc), consistent with the sizes of other massive star-forming disks at z~2. In many cases we find evidence of blue clumps within the sources, with the mass-dominant disk becoming more significant at longer wavelengths. Finally, only a minority of the sources show evidence for a major galaxy-galaxy interaction. Taken together, these results support the view that most (sub-)mm galaxies at z~2 are simply the most extreme examples of normal star-forming galaxies at that era.Comment: 30 pages, 9 figure

VLT-SINFONI integral field spectroscopy of low-z luminous and ultraluminous infrared galaxies

We present a 2D study of the internal extinction on (sub)kiloparsec scales of a sample of local (z < 0.1) LIRGs (10) and ULIRGs (7), based on near-infrared Paα, Brδ, and Brγ line ratios, obtained with VLT-SINFONI integral-field spectroscopy (IFS). The 2D extinction (AV) distributions of the objects, map regions of ~ 3 × 3 kpc (LIRGs) and ~ 12 × 12 kpc (ULIRGs), with average angular resolutions (FWHM) of ~0.2 kpc and ~0.9 kpc, respectively. The individual AV galaxy distributions indicate a very clumpy dust structure already on sub-kiloparsec scales, with values (per spaxel) ranging from AV ~ 1 to 20 mag in LIRGs, and from AV ~ 2 to 15 mag in ULIRGs. As a class, the median values of the distributions are AV = 5.3 mag and AV = 6.5 mag for the LIRG and ULIRG subsamples, respectively. In ~70% of the objects, the extinction peaks at the nucleus with values ranging from AV ~ 3 to 17 mag. Within each galaxy, the AV radial profile shows a mild decrement in LIRGs within the inner 2 kpc radius, while the same radial variation is not detected in ULIRGs, likely because of the lower linear scale resolution of the observations at the distance of ULIRGs. We evaluated the effects of the galaxy distance in the measurements of the extinction as a function of the linear scale (in kpc) of the spaxel (i.e. due to the limited angular resolution of the observations). If the distribution of the gas/dust and star-forming regions in local LIRGs (63 Mpc, 40 pc/spaxel on average) is the same for galaxies at greater distances, the observed median AV values based on emission line ratios would be a factor ~0.8 lower at the average distance of our ULIRG sample (328 Mpc, 0.2 kpc/spaxel), and a factor ~0.67 for galaxies located at distances of more than 800 Mpc (0.4 kpc/spaxel). This distance effect would have implications for deriving the intrinsic extinction in high-z star-forming galaxies and for subsequent properties such as star formation rate, star formation surface density, and KS- law, based on Hα line fluxes. If local LIRGs are analogues of the main-sequence star-forming galaxies at cosmological distances, the extinction values (AV) derived from the observed emission lines in these high-z sources would need to be increased by a factor 1.4 on average

Anabolic effect of estrogen replacement on bone in postmenopausal women with osteoporosis: Histomorphometric evidence in a longitudinal study.

It is well recognized that estrogen (E2) prevents postmenopausal bone loss by suppressing bone resorption. Despite evidence that E2 may also stimulate bone formation in animals, an anabolic effect in humans is still controversial. To investigate this, we studied 22 older postmenopausal females, with a mean age of 65.4 yr and mean interval of 16.9 yr since menopause and low bone mineral density. Transcortical iliac bone biopsies were performed before and 6 yr after E2 replacement therapy (ERT) [75 mg percutaneous E2 replaced 6-monthly plus oral medroxy progesterone acetate (5 mg daily) for 10 days each calendar month]. The mean serum E2 level after 6 yr of treatment was 1077 (range, 180-2568) pmol/L. Bone mineral density improved in every patient, with a median increase of 31.4% at the lumbar spine and 15.1% at the proximal femur. Bone histomorphometry showed an increase in cancellous bone volume from 10.75% to 17.31% (P &amp;lt; 0.001). The wall thickness after 6 yr of E2 treatment was 38.30 μm compared with 31.20 μm before commencement of ERT (P &amp;lt; 0.0005), indicating net bone gain. This is the first report showing histological evidence for an increase in cancellous bone volume, together with an increase in wall thickness, in a longitudinal follow-up study of ERT in older postmenopausal women. Our results show that E2 is capable of exerting an anabolic effect in women with osteoporosis, even when started well into the menopause.</jats:p