2,235 research outputs found
534 SIX-MONTH EFFICACY OF INTRA-ARTICULAR HYALURONIC ACID FOR CARPOMETACARPAL JOINT OSTEOARTHRITIS
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Estimating photometric redshifts with artificial neural networks
A new approach to estimating photometric redshifts - using Artificial Neural
Networks (ANNs) - is investigated. Unlike the standard template-fitting
photometric redshift technique, a large spectroscopically-identified training
set is required but, where one is available, ANNs produce photometric redshift
accuracies at least as good as and often better than the template-fitting
method. The Bayesian priors on the underlying redshift distribution are
automatically taken into account. Furthermore, inputs other than galaxy colours
- such as morphology, angular size and surface brightness - may be easily
incorporated, and their utility assessed.
Different ANN architectures are tested on a semi-analytic model galaxy
catalogue and the results are compared with the template-fitting method.
Finally the method is tested on a sample of ~ 20000 galaxies from the Sloan
Digital Sky Survey. The r.m.s. redshift error in the range z < 0.35 is ~ 0.021.Comment: Submitted to MNRAS, 9 pages, 9 figures, substantial improvements to
paper structur
The not-so-massive black hole in the microquasar GRS1915+105
We present a new dynamical study of the black hole X-ray transient GRS1915+105 making use of near-infrared spectroscopy obtained with X-shooter at the VLT. We detect a large number of donor star absorption features across a wide range of wavelengths spanning the H and K bands. Our 24 epochs covering a baseline of over 1 year permit us to determine a new binary ephemeris including a refined orbital period of P=33.85 +/- 0.16 d. The donor star radial velocity curves deliver a significantly improved determination of the donor semi-amplitude which is both accurate (K_2=126 +/- 1 km/s) and robust against choice of donor star template and spectral features used. We furthermore constrain the donor star's rotational broadening to vsini=21 +/-4 km/s, delivering a binary mass ratio of q=0.042 +/- 0.024. If we combine these new constraints with distance and inclination estimates derived from modelling the radio emission, a black hole mass of M_BH=10.1 +/- 0.6 M_sun is inferred, paired with an evolved mass donor of M_2=0.47 +/- 0.27 M_sun. Our analysis suggests a more typical black hole mass for GRS1915+105 rather than the unusually high values derived in the pioneering dynamical study by Greiner et al. (2001). Our data demonstrate that high-resolution infrared spectroscopy of obscured accreting binaries can deliver dynamical mass determinations with a precision on par with optical studies
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Complement Activation in Patients With Probable Systemic Lupus Erythematosus and Ability to Predict Progression to American College of Rheumatology-Classified Systemic Lupus Erythematosus.
ObjectiveTo evaluate the frequency of cell-bound complement activation products (CB-CAPs) as a marker of complement activation in patients with suspected systemic lupus erythematosus (SLE) and the usefulness of this biomarker as a predictor of the evolution of probable SLE into SLE as classified by the American College of Rheumatology (ACR) criteria.MethodsPatients in whom SLE was suspected by lupus experts and who fulfilled 3 ACR classification criteria for SLE (probable SLE) were enrolled, along with patients with established SLE as classified by both the ACR and the Systemic Lupus International Collaborating Clinics (SLICC) criteria, patients with primary Sjögren's syndrome (SS), and patients with other rheumatic diseases. Individual CB-CAPs were measured by flow cytometry, and positivity rates were compared to those of commonly assessed biomarkers, including serum complement proteins (C3 and C4) and autoantibodies. The frequency of a positive multianalyte assay panel (MAP), which includes CB-CAPs, was also evaluated. Probable SLE cases were followed up prospectively.ResultsThe 92 patients with probable SLE were diagnosed more recently than the 53 patients with established SLE, and their use of antirheumatic medications was lower. At the enrollment visit, more patients with probable SLE were positive for CB-CAPs (28%) or MAP (40%) than had low complement levels (9%) (P = 0.0001 for each). In probable SLE, MAP scores of >0.8 at enrollment predicted fulfillment of a fourth ACR criterion within 18 months (hazard ratio 3.11, P < 0.01).ConclusionComplement activation occurs in some patients with probable SLE and can be detected with higher frequency by evaluating CB-CAPs and MAP than by assessing traditional serum complement protein levels. A MAP score above 0.8 predicts transition to classifiable SLE according to ACR criteria
Dark Matter in the Universe: Evidence, Candidates and Searches
Contribution from the students of the 4th CERNCLAF School of High-Energy Physics who participated in the Discussion Session addressing the issues of dark matter in the Universe
The [1,2,4]Triazolo[4,3-a]pyridine as a New Player in the Field of IDO1 Catalytic Holo-Inhibitors
Inhibitors of indoleamine 2,3-dioxygenase 1 (IDO1) are considered a promising strategy in cancer immunotherapy as they are able to boost the immune response and to work in synergy with other immunotherapeutic agents. Despite the fact that no IDO1 inhibitor has been approved so far, recent studies have shed light on the additional roles that IDO1 mediates beyond its catalytic activity, conferring new life to the field. Here we present a novel class of compounds originated from a structure-based virtual screening made on IDO1 active site. The starting hit compound is a novel chemotype based on a [1,2,4]triazolo[4,3-a]pyridine scaffold, so far underexploited among the heme binding moieties. Thanks to the rational and in silico-guided design of analogues, an improvement of the potency to sub-micromolar levels has been achieved, with excellent in vitro metabolic stability and exquisite selectivity with respect to other heme-containing enzymes
Reductions in disease activity in the AMPLE trial: clinical response by baseline disease duration
Objectives: To evaluate clinical response by baseline disease duration using 2-year data from the AMPLE trial.
Methods: Patients were randomised to subcutaneous abatacept 125 mg weekly or adalimumab 40 mg biweekly, with background methotrexate. As part of a post hoc analysis, the achievement of validated definitions of remission (Clinical Disease Activity Index (CDAI) ≤2.8, Simplified Disease Activity Index (SDAI) ≤3.3, Routine Assessment of Patient Index Data 3 (RAPID3) ≤3.0, Boolean score ≤1), low disease activity (CDAI \u3c10, SDAI \u3c11, RAPID3 ≤6.0), Health Assessment Questionnaire-Disability Index response and American College of Rheumatology responses were evaluated by baseline disease duration (≤6 vs \u3e6 months). Disease Activity Score 28 (C-reactive protein) \u3c2.6 or ≤3.2 and radiographic non-progression in patients achieving remission were also evaluated.
Results: A total of 646 patients were randomised and treated (abatacept, n=318; adalimumab, n=328). In both treatment groups, comparable responses were achieved in patients with early rheumatoid arthritis (≤6 months) and in those with later disease (\u3e6 months) across multiple clinical measures
Conclusions: Abatacept or adalimumab with background methotrexate were associated with similar onset and sustainability of response over 2 years. Patients treated early or later in the disease course achieved comparable clinical responses
The VIRMOS deep imaging survey: III. ESO/WFI deep U-band imaging of the 0226-04 deep field
In this paper we describe the U-band imaging of the F02 deep field, one of
the fields in the VIRMOS Deep Imaging Survey. The observations were done at the
ESO/MPG 2.2m telescope at La Silla (Chile) using the 8k x 8k Wide-Field Imager
(WFI). The field is centered at alpha(J2000)=02h 26m 00s and
delta(J2000)=-04deg 30' 00", the total covered area is 0.9 deg**2 and the
limiting magnitude (50% completeness) is U(AB) ~ 25.4 mag. Reduction steps,
including astrometry, photometry and catalogue extraction, are first discussed.
The achieved astrometric accuracy (RMS) is ~ 0.2" with reference to the I-band
catalog and ~ 0.07" internally (estimated from overlapping sources in different
exposures). The photometric accuracy including uncertainties from photometric
calibration, is < 0.1 mag. Various tests are then performed as a quality
assessment of the data. They include: (i) the color distribution of stars and
galaxies in the field, done together with the BVRI data available from the
VIMOS survey; (ii) the comparison with previous published results of U-band
magnitude-number counts of galaxies.Comment: 10 pages, 13 figures, accepted for publication on Astronomy and
Astrophysic
V819 Tau: A Rare Weak-Lined T Tauri Star with a Weak Infrared Excess
We use Spitzer data to infer that the small infrared excess of V819 Tau, a
weak-lined T Tauri star in Taurus, is real and not attributable to a
"companion" 10 arcsec to the south. We do not confirm the mid-infrared excess
in HBC 427 and V410 X-ray 3, which are also non-accreting T Tauri stars in the
same region; instead, for the former object, the excess arises from a red
companion 9 arcsec to the east. A single-temperature blackbody fit to the
continuum excess of V819 Tau implies a dust temperature of 143 K; however, a
better fit is achieved when the weak 10 and 20 micron silicate emission
features are also included. We infer a disk of sub-micron silicate grains
between about 1 AU and several 100 AU with a constant surface density
distribution. The mid-infrared excess of V819 Tau can be successfully modeled
with dust composed mostly of small amorphous olivine grains at a temperature of
85 K, and most of the excess emission is optically thin. The disk could still
be primordial, but gas-poor and therefore short-lived, or already at the debris
disk stage, which would make it one of the youngest debris disk systems known.Comment: 7 pages, 7 figures; accepted for publication in Ap
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