567 research outputs found
MUSE-inspired view of the quasar Q2059-360, its Lyman alpha blob, and its neighborhood
The radio-quiet quasar Q2059-360 at redshift is known to be close to
a small Lyman blob (LAB) and to be absorbed by a proximate damped
Ly (PDLA) system.
Here, we present the Multi Unit Spectroscopic Explorer (MUSE) integral field
spectroscopy follow-up of this quasi-stellar object (QSO). Our primary goal is
to characterize this LAB in detail by mapping it both spatially and spectrally
using the Ly line, and by looking for high-ionization lines to
constrain the emission mechanism.
Combining the high sensitivity of the MUSE integral field spectrograph
mounted on the Yepun telescope at ESO-VLT with the natural coronagraph provided
by the PDLA, we map the LAB down to the QSO position, after robust subtraction
of QSO light in the spectral domain.
In addition to confirming earlier results for the small bright component of
the LAB, we unveil a faint filamentary emission protruding to the south over
about 80 pkpc (physical kpc); this results in a total size of about 120 pkpc.
We derive the velocity field of the LAB (assuming no transfer effects) and map
the Ly line width. Upper limits are set to the flux of the N V , C IV , He II , and C III] lines. We have discovered two probable Ly emitters at the
same redshift as the LAB and at projected distances of 265 kpc and 207 kpc from
the QSO; their Ly luminosities might well be enhanced by the QSO
radiation. We also find an emission line galaxy at near the line of
sight to the QSO.
This LAB shares the same general characteristics as the 17 others surrounding
radio-quiet QSOs presented previously. However, there are indications that it
may be centered on the PDLA galaxy rather than on the QSO.Comment: Accepted for publication in Astronomy & Astrophysics; 16 pages, 19
figure
Astrocladistics: a phylogenetic analysis of galaxy evolution I. Character evolutions and galaxy histories
This series of papers is intended to present astrocladistics in some detail
and evaluate this methodology in reconstructing phylogenies of galaxies. Being
based on the evolution of all the characters describing galaxies, it is an
objective way of understanding galaxy diversity through evolutionary
relationships. In this first paper, we present the basic steps of a cladistic
analysis and show both theoretically and practically that it can be applied to
galaxies. For illustration, we use a sample of 50 simulated galaxies taken from
the GALICS database, which are described by 91 observables (dynamics, masses
and luminosities). These 50 simulated galaxies are indeed 10 different galaxies
taken at 5 cosmological epochs, and they are free of merger events. The
astrocladistic analysis easily reconstructs the true chronology of evolution
relationships within this sample. It also demonstrates that burst characters
are not relevant for galaxy evolution as a whole. A companion paper is devoted
to the formalization of the concepts of formation and diversification in galaxy
evolution.Comment: 16 pages, 6 figure
Astrocladistics: a phylogenetic analysis of galaxy evolution II. Formation and diversification of galaxies
This series of papers is intended to evaluate astrocladistics in
reconstructing phylogenies of galaxies. The objective of this second paper is
to formalize the concept of galaxy formation and to identify the processes of
diversification. We show that galaxy diversity can be expected to organize
itself in a hierarchy. In order to better understand the role of mergers, we
have selected a sample of 43 galaxies from the GALICS database built from
simulations with a hybrid model for galaxy formation studies. These simulated
galaxies, described by 119 characters and considered as representing still
undefined classes, have experienced different numbers of merger events during
evolution. Our cladistic analysis yields a robust tree that proves the
existence of a hierarchy. Mergers, like interactions (not taken into account in
the GALICS simulations), are probably a strong driver for galaxy
diversification. Our result shows that mergers participate in a branching type
of evolution, but do not seem to play the role of an evolutionary clock.Comment: 14 pages, 4 figure
Hypertension in older patients, a retrospective cohort study
Background: It is unknown to what extent General Practitioners (GPs) manage hypertension (HT) differently in older patients, as compared to younger age groups. The purpose of our study was to compare HT management in older patients to younger age groups. Methods: We performed a retrospective cohort study of patients of 159 GP's practices in the Integrated Primary Care Information (IPCI) database. The study period lasted from September 2010 through December 2012. The study population consisted of all patients aged 60 years or older with at least one blood pressure (BP) measurement during the inclusion period, without pre-existent HT, diabetes mellitus (DM) or atherosclerotic cardiovascular disease at time of study start. Study outcomes were a diagnosis of HT within one month after cohort entry and the use of antihypertensive medication within 4 months after cohort entry in HT diagnosed patients. We compared the incidence of outcomes between the age groups, stratified by systolic blood pressure (SBP). Logistic regression analysis was used to assess the influence of age-adjusted SBP Z-scores, age and gender on the outcomes. Results: We included 19,500 patients from 159 GP's practices of whom 1,181 (6.1 %) were newly diagnosed with HT. Corrected for age-adjusted SBP, older patients were less likely to be diagnosed with HT (odds ratio per year age increase 0.98, p < 0.001). Corrected for age-adjusted SBP, no significant effect of age on the probability of treatment in newly diagnosed HT patients was observed (p = 0.82). Conclusions: This study showed that GPs are less inclined to diagnose HT with increasing patient age, but do not withhold treatment when they diagnose HT in older patients
Epidemiologic observations guiding clinical application of a urinary peptidomic marker of diastolic left ventricular dysfunction
Hypertension, obesity, and old age are major risk factors for left ventricular (LV) diastolic dysfunction (LVDD), but easily applicable screening tools for people at risk are lacking. We investigated whether HF1, a urinary biomarker consisting of 85 peptides, can predict over a 5-year time span mildly impaired diastolic LV function as assessed by echocardiography. In 645 white Flemish (50.5% women; 50.9 years [mean]), we measured HF1 by capillary electrophoresis coupled with mass spectrometry in 2005-2010. We measured early (E) and late (A) peak velocities of the transmitral blood flow and early (e') and late (a') mitral annular peak velocities and their ratios in 2009-2013. In multivariable-adjusted analyses, per 1-standard deviation increment in HF1, e' was -0.193 cm/s lower (95% confidence interval: -0.352 to -0.033; P = .018) and E/e' 0.174 units higher (0.005-0.342; P = .043). Of 645 participants, 179 (27.8%) had LVDD at follow-up, based on impaired relaxation in 69 patients (38.5%) or an elevated filling pressure in the presence of a normal (74 [43.8%]) or low (36 [20.1%]) age-specific E/A ratio. For a 1-standard deviation increment in HF1, the adjusted odds ratio was 1.37 (confidence interval, 1.07-1.76; P = .013). The integrated discrimination (+1.14%) and net reclassification (+31.7%) improvement of the optimized HF1 threshold (-0.350) in discriminating normal from abnormal diastolic LV function at follow-up over and beyond other risk factors was significant (P â€Â .024). In conclusion, HF1 may allow screening for LVDD over a 5-year horizon in asymptomatic people
Galaxy Counterparts of metal-rich Damped Lyman-alpha Absorbers - I: The case of the z=2.35 DLA towards Q2222-0946
We have initiated a survey using the newly commissioned X-shooter
spectrograph to target candidate relatively metal-rich damped Lyman-alpha
absorbers (DLAs). The spectral coverage of X-shooter allows us to search for
not only Lyman-alpha emission, but also rest-frame optical emission lines. We
have chosen DLAs where the strongest rest-frame optical lines ([OII], [OIII],
Hbeta and Halpha) fall in the NIR atmospheric transmission bands. In this first
paper resulting from the survey, we report on the discovery of the galaxy
counterpart of the z_abs = 2.354 DLA towards the z=2.926 quasar Q2222$-0946.
This DLA is amongst the most metal-rich z>2 DLAs studied so far at comparable
redshifts and there is evidence for substantial depletion of refractory
elements onto dust grains. We measure metallicities from ZnII, SiII, NiII, MnII
and FeII of -0.46+/-0.07, -0.51+/-0.06, -0.85+/-0.06, -1.23+/-0.06, and
-0.99+/-0.06, respectively. The galaxy is detected in the Lyman-alpha, [OIII]
lambda4959,5007 Halpha emission lines at an impact parameter of about 0.8
arcsec (6 kpc at z_abs = 2.354). We infer a star-formation rate of 10 M_sun
yr^-1, which is a lower limit due to the possibility of slit-loss. Compared to
the recently determined Halpha luminosity function for z=2.2 galaxies the
DLA-galaxy counterpart has a luminosity of L~0.1L^*_Halpha. The emission-line
ratios are 4.0 (Lyalpha/Halpha) and 1.2 ([OIII]/Halpha). The Lyalpha line shows
clear evidence for resonant scattering effects, namely an asymmetric,
redshifted (relative to the systemic redshift) component and a much weaker
blueshifted component. The fact that the blueshifted component is relatively
weak indicates the presence of a galactic wind. The properties of the galaxy
counterpart of this DLA is consistent with the prediction that metal-rich DLAs
are associated with the most luminous of the DLA-galaxy counterparts.Comment: 9 pages, 7 figures. Accepted for publication in MNRA
Laboratory testing in patients treated with direct oral anticoagulants: a practical guide for clinicians
Click to hear Dr Baglin's perspective on the role of the laboratory in treatment with new oral anticoagulants SUMMARY: One of the key benefits of the direct oral anticoagulants (DOACs) is that they do not require routine laboratory monitoring. Nevertheless, assessment of DOAC exposure and anticoagulant effects may become useful in various clinical scenarios. The five approved DOACs (apixaban, betrixaban, dabigatran etexilate, edoxaban and rivaroxaban) have different characteristics impacting assay selection and the interpretation of results. This article provides an updated overview on (i) which test to use (and their advantages and limitations), (ii) when to assay DOAC levels, (iii) how to interpret the results relating to bleeding risk, emergency situations and perioperative management, and (iv) what is the impact of DOACs on routine and specialized coagulation assays. Assays for anti-Xa or anti-IIa activity are the preferred methods when quantitative information is useful, although the situations in which to test for DOAC levels are still debated. Different reagent sensitivities and variabilities in laboratory calibrations impact assay results. International calibration standards for all specific tests for each DOAC are needed to reduce the inter-laboratory variability and allow inter-study comparisons. The impact of the DOACs on hemostasis testing may cause false-positive or false-negative results; however, these can be minimized by using specific assays and collecting blood samples at trough concentrations. Finally, prospective clinical trials are needed to validate the safety and efficacy of proposed laboratory thresholds in relation to clinical decisions. We offer recommendations on the tests to use for measuring DOACs and practical guidance on laboratory testing to help patient management and avoid diagnostic errors. ispartof: Journal of Thrombosis and Haemostasis vol:16 issue:2 pages:209-219 ispartof: location:England status: publishe
The unusual NIV]-emitter galaxy GDS J033218.92-275302.7: star formation or AGN-driven winds from a massive galaxy at z=5.56
Aims: We investigate the nature of the source GDS J033218.92-275302.7at
redshift ~ 5.56. Methods: The SED of the source is well sampled by 16 bands
photometry, from UV-optical, near infrared and mid-infrared (MID-IR).The
detection of signal in the MID-IR Spitzer/IRAC bands 5.8, 8.0 um -- where the
nebular emission contribution is less effective -- suggests the presence of a
Balmer break, signature of an underlying stellar population formed at earlier
epochs. The optical spectrum shows a clear Lya emission line together with
semi-forbidden NIV] 1483.3-1486.5 also in emission. Results: From the SED
fitting and the Lya modelling it turns out that the source seems to have an
evolved component with stellar mass of ~5 x10^(10) Msolar and age ~ 0.4 Gyrs,
and a young component with an age of ~ 0.01 Gyrs and SFR in the range of 30-200
Msolar yr^(-1). The limits on the effective radius derived from the ACS/z850
and VLT/Ks bands indicate that this galaxy is denser than the local ones with
similar mass. A relatively high nebular gas column density is favored from the
Lya line modelling (NHI>=10^(21) cm^(-2)). A vigorous outflow (~ 450 km/s) has
been measured from the optical spectrum,consistent with the Lya modelling. From
ACS observations it turns out that the region emitting Lya photons is spatially
compact and of the same order of the effective radius estimated at the ~1400A
rest-frame wavelength, whose emission is dominated by the stellar continuum
and/or AGN. The gas is blown out from the central region,but given the mass of
the galaxy it is uncertain whether it will pollute the IGM to large distances.
We argue that a burst of star formation in a dense gas environment is active
(possibly containing hot and massive stars and/or a low luminosity AGN),
superimposed to an already formed fraction of stellar mass (abridged).Comment: 13 pages, 9 figures (published on A&A). Here replaced with a typo
fixed in the footnote of Sect. 4.2 and with four updated references. Results
unchange
The Great Observatories Origins Deep Survey - VLT/VIMOS Spectroscopy in the GOODS-South Field: Part II
We present the full data set of the VIMOS spectroscopic campaign of the
ESO/GOODS program in the CDFS, which complements the FORS2 ESO/GOODS
spectroscopic campaign. The GOODS/VIMOS spectroscopic campaign is structured in
two separate surveys using two different VIMOS grisms. The VIMOS Low Resolution
Blue (LR-Blue) and Medium Resolution (MR) orange grisms have been used to cover
different redshift ranges. The LR-Blue campaign is aimed at observing galaxies
mainly at 1.8<z<3.5, while the MR campaign mainly aims at galaxies at z<1 and
Lyman Break Galaxies (LBGs) at z>3.5. The full GOODS/VIMOS spectroscopic
campaign consists of 20 VIMOS masks. This release adds 8 new masks to the
previous release (12 masks, Popesso et al. 2009). In total we obtained 5052
spectra, 3634 from the 10 LR-Blue masks and 1418 from the 10 MR masks. A
significant fraction of the extracted spectra comes from serendipitously
observed sources: ~21% in the LR-Blue and ~16% in the MR masks. We obtained
2242 redshifts in the LR-Blue campaign and 976 in the MR campaign for a total
success rate of 62% and 69% respectively, which increases to 66% and 73% if
only primary targets are considered. The typical redshift uncertainty is
estimated to be ~0.0012 (~255 km/s) for the LR-Blue grism and ~0.00040 (~120
km/s) for the MR grism. By complementing our VIMOS spectroscopic catalog with
all existing spectroscopic redshifts publicly available in the CDFS, we
compiled a redshift master catalog with 7332 entries, which we used to
investigate large scale structures out to z~3.7. We produced stacked spectra of
LBGs in a few bins of equivalent width (EW) of the Ly-alpha and found evidence
for a lack of bright LBGs with high EW of the Ly-alpha. Finally, we obtained
new redshifts for 12 X-ray sources of the CDFS and extended-CDFS.Comment: 22 pages, 20 figures, accepted for publication on Astronomy and
Astrophysics, catalogs and data products are available at
http://archive.eso.org/cms/eso-data/data-packages/goods-vimos-spectroscopy-data-release-version-2.0/,
for ESO-GOODS related material consult
http://www.eso.org/sci/activities/projects/goods
A pooled analysis of mortality in patients with COPD receiving triple therapy versus dual bronchodilation
Peer reviewedPostprin
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