487 research outputs found
Constraining halo occupation properties of X-ray AGNs using clustering of Chandra sources in the Bootes survey region
We present one of the most precise measurement to date of the spatial
clustering of X-ray selected AGNs using a sample derived from the Chandra X-ray
Observatory survey in the Bootes field. The real-space two-point correlation
function over a redshift interval from z=0.17 to z~3 is well described by the
power law, xi(r)=(r/r0)^-gamma, for comoving separations r<~20h^-1 Mpc. We find
gamma=1.84+-0.12 and r0 consistent with no redshift trend within the sample
(varying between r0=5.5+-0.6 h^-1 Mpc for =0.37 and r0=6.9+-1.0 h^-1 Mpc for
=1.28). Further, we are able to measure the projections of the two-point
correlation function both on the sky plane and in the line of sight. We use
these measurements to show that the Chandra/Bootes AGNs are predominantly
located at the centers of dark matter halos with the circular velocity Vmax>320
km/s or M_200 > 4.1e12 h^-1 Msun, and tend to avoid satellite galaxies in halos
of this or higher mass. The halo occupation properties inferred from the
clustering properties of Chandra/Bootes AGNs --- the mass scale of the parent
dark matter halos, the lack of significant redshift evolution of the clustering
length, and the low satellite fraction --- are broadly consistent with the
Hopkins et al. scenario of quasar activity triggered by mergers of
similarly-sized galaxies.Comment: Accepted to ApJ. The revision matches the accepted version. The most
significant changes include the recalculation of uncertainties using mock
catalogs and explicit comparison with the AGN HOD studies based on projected
correlation function, w(rp
CO80 89. Estudio multicĂ©ntrico español de la capacidad predictiva de las escalas de riesgo CHADS2 y CHA2DS2vasc en el accidente cerebrovascular tras cirugĂa coronaria aislada
ObjetivosValidar las escalas de riesgo CHADS2 y CHA2DS-2VASC como modelos predictivos de desarrollo de accidente cerebrovascular (ACV) en cirugĂa coronaria aislada (CCA).Material y mĂ©todosPacientes consecutivos sometidos a CCA en 16 hospitales españoles. Excluidos casos con igual o mĂĄs de una variable/s incompleta/s. Puntuaciones CHADS2 y CHA2DS2VASC computadas para todos los pacientes, considerĂĄndose variable de resultado la apariciĂłn de ACV (ataque isquĂ©mico transitorio [AIT]/ictus) perioperatorio precoz (primer mes postoperatorio y/o alta hospitalaria). AnĂĄlisis uni y multivariante. La capacidad discriminativa fue cuantificada por el cĂĄlculo del ĂĄrea bajo la curva ROC (AUC).ResultadosVeinte mil novecientos ochenta pacientes incluidos, 282 desarrollaron ACV postoperatorio (1,34%). La incidencia de ACV fue superior en pacientes con insuficiencia cardĂaca congestiva (ICC) y/o fracciĂłn de eyecciĂłn inferior al 40% (4,10 vs 0,83%), diabĂ©ticos (1,70 vs 1,11%), hipertensos (1,60 vs 0,98%), ACV previo (2,72 vs 1,26%) y a enfermedad arterial perifĂ©rica (EAP) (3,04 vs 1,04%; p < 0,05). En el anĂĄlisis multivariante, ICCC (odds ratio [OR]: 4,06), ACV previo (OR: 1,48), EAP (OR: 1,49) constituyeron factores de riesgo independientes para el desarrollo de ACV postoperatorio (p < 0,05). El AUC para CHADS2 fue 0,666, y para CHA2DS2VASc 0,655 (p < 0,0001). La distribuciĂłn de las tasas de ACV postoperatorio segĂșn las puntuaciones de las anteriores escalas se recoge en la figura 1 (p < 0,0001). Figura 1Tasas de ACV postoperatorio en pacientes sometidos a CCA segĂșn puntuaciones de las escalas CHADS2 (gris) y CHA2DS2VASC (negro).ConclusionesLas escalas de riesgo CHADS2 y CHA2DS-2VASC pueden resultar Ăștiles en la prĂĄctica clĂnica para estratificar el riesgo de desarrollo de ACV postoperatorio en pacientes sometidos a CCA
The Cooperative Participatory Evaluation of Renewable Technologies on Ecosystem Services (CORPORATES)
Publisher PD
The Chandra XBootes Survey - III: Optical and Near-IR Counterparts
The XBootes Survey is a 5-ks Chandra survey of the Bootes Field of the NOAO
Deep Wide-Field Survey (NDWFS). This survey is unique in that it is the largest
(9.3 deg^2), contiguous region imaged in X-ray with complementary deep optical
and near-IR observations. We present a catalog of the optical counterparts to
the 3,213 X-ray point sources detected in the XBootes survey. Using a Bayesian
identification scheme, we successfully identified optical counterparts for 98%
of the X-ray point sources. The optical colors suggest that the optically
detected galaxies are a combination of z<1 massive early-type galaxies and
bluer star-forming galaxies whose optical AGN emission is faint or obscured,
whereas the majority of the optically detected point sources are likely quasars
over a large redshift range. Our large area, X-ray bright, optically deep
survey enables us to select a large sub-sample of sources (773) with high X-ray
to optical flux ratios (f_x/f_o>10). These objects are likely high redshift
and/or dust obscured AGN. These sources have generally harder X-ray spectra
than sources with 0.1<f_x/f_o<10. Of the 73 X-ray sources with no optical
counterpart in the NDWFS catalog, 47 are truly optically blank down to R~25.5
(the average 50% completeness limit of the NDWFS R-band catalogs). These
sources are also likely to be high redshift and/or dust obscured AGN.Comment: 19 pages, 13 figures, ApJ accepted. Catalog can be found at:
http://www.noao.edu/noao/noaodeep or
ftp://archive.noao.edu/pub/catalogs/xbootes
XBootes: An X-Ray Survey of the NDWFS Bootes Field - Paper I Overview and Initial Results
We obtained a 5 ksec deep Chandra X-ray Observatory ACIS-I map of the 9.3
square degree Bootes field of the NOAO Deep Wide-Field Survey. Here we describe
the data acquisition and analysis strategies leading to a catalog of 4642
(3293) point sources with 2 or more (4 or more) counts, corresponding to a
limiting flux of roughly 4(8)x10^{-15} erg cm^{-2}s^{-1} in the 0.5-7 keV band.
These Chandra XBootes data are unique in that they consitute the widest
contiguous X-ray field yet observed to such a faint flux limit. Because of the
extraordinarily low background of the ACIS, we expect only 14% (0.7%) of the
sources to be spurious. We also detected 43 extended sources in this survey.
The distribution of the point sources among the 126 pointings (ACIS-I has a 16
x 16 arcminute field of view) is consistent with Poisson fluctuations about the
mean of 36.8 sources per pointing. While a smoothed image of the point source
distribution is clumpy, there is no statistically significant evidence of large
scale filamentary structure. We do find however, that for theta>1 arcminute,
the angular correlation function of these sources is consistent with previous
measurements, following a power law in angle with slope -0.7. In a 1.4 deg^{2}
sample of the survey, approximately 87% of the sources with 4 or more counts
have an optical counterpart to R ~26 mag. As part of a larger program of
optical spectroscopy of the NDWFS Bootes area, spectra have been obtained for
\~900 of the X-ray sources, most of which are QSOs or AGN.Comment: 18 Pages, 10 figures (AASTex Preprint format
Flexible ordering of antibody class switch and V(D)J joining during B-cell ontogeny
V(D)J joining is mediated by RAG recombinase during early B-lymphocyte development in the bone marrow (BM). Activation-induced deaminase initiates isotype switching in mature B cells of secondary lymphoid structures. Previous studies questioned the strict ontological partitioning of these processes. We show that pro-B cells undergo robust switching to a subset of immunoglobulin H (IgH) isotypes. Chromatin studies reveal that in pro-B cells, the spatial organization of the Igh locus may restrict switching to this subset of isotypes. We demonstrate that in the BM, V(D)J joining and switching are interchangeably inducible, providing an explanation for the hyper-IgE phenotype of Omenn syndrome
Deliberative and non-monetary valuation methods
Abstract There is an increasing interest in methods that can understand our values of ecosystem services in broad and multidimensional way. This chapter discusses a range of deliberative, analytical-deliberative, psychological and interpretive approaches to value the environment. Deliberative methods allow people to ponder, debate and negotiate their values, which can inform, moralise and democratise the valuation process. Analytical-deliberative approaches combine deliberative methods with more formal decision-support tools. Interpretive methods help us understand the narratives of places and what they mean to us as individuals and to our communities and culture. Psychological methods can survey the multi-faceted nature of how ecosystem services contribute to human well-being, and can also investigate our deeper held, 'transcendental' values. The way we approach valuation impacts on the type of values that are highlighted. Embracing values as a pluralistic concept means that, to comprehensively value ecosystem services, we need to embrace a diversity of methods to assess them
Experiences, adherence and satisfaction with a combined exercise and dietary intervention for patients with ovarian cancer undergoing chemotherapy:A mixed-methods study
Objective: This study examined experiences, adherence and satisfaction with a combined exercise and dietary intervention in patients with ovarian cancer and their healthcare professionals (HCPs) as part of the randomized PADOVA trial. Methods: A mixed-methods approach was used in 24 patients with ovarian cancer receiving first-line chemotherapy who were randomly allocated to a combined exercise and dietary intervention or usual care with counseling sessions post-treatment. Qualitative data on intervention experiences, adherence and satisfaction was collected using semi-structured interviews with patients and their HCPs (n = 18 physical therapists; n = 5 dietitians). Quantitative data on adherence and satisfaction was collected to provide context to qualitative data. Results: Exercise relative dose intensity ranged from 36 to 100% (median 72%) and patients attended 33â133% (median 100%) of the prescribed dietary counseling sessions. Patients appreciated guidance on exercise and nutrition and perceived benefits including improved physical fitness, quality of life, peer support and recovery after surgery and/or chemotherapy cycles. Both patients and HCPs were satisfied with the intervention and perceived that participation exceeded prior expectations. Median patient satisfaction score with the intervention was 8.5 out of 10. Suggestions for improving the intervention included further personalization of the number, content and scheduling of the sessions to preferences of patients and HCPs. Patients in the usual care group reported counseling sessions post-chemotherapy to be too little too late. Conclusions: Patients with ovarian cancer adhered well to the intervention. Numerous perceived benefits of the intervention were reported by patients and HCPs. Good adherence and positive experiences support successful implementation in clinical practice
The Mid-Infrared Properties of X-ray Sources
We combine the results of the Spitzer IRAC Shallow Survey and the Chandra
XBootes Survey of the 8.5 square degrees Bootes field of the NOAO Deep Wide-
Field Survey to produce the largest comparison of mid-IR and X-ray sources to
date. The comparison is limited to sources with X-ray fluxes >8x10-15 erg
cm-2s-1 in the 0.5-7.0 keV range and mid-IR sources with 3.6 um fluxes brighter
than 18.4 mag (12.3 uJy). In this most sensitive IRAC band, 85% of the 3086
X-ray sources have mid-IR counterparts at an 80% confidence level based on a
Bayesian matching technique. Only 2.5% of the sample have no IRAC counterpart
at all based on visual inspection. Even for a smaller but a significantly
deeper Chandra survey in the same field, the IRAC Shallow Survey recovers most
of the X-ray sources. A majority (65%) of the Chandra sources detected in all
four IRAC bands occupy a well-defined region of IRAC [3.6] - [4.5] vs [5.8] -
[8.0] color-color space. These X-ray sources are likely infrared luminous,
unobscured type I AGN with little mid-infrared flux contributed by the AGN host
galaxy. Of the remaining Chandra sources, most are lower luminosity type I and
type II AGN whose mid-IR emission is dominated by the host galaxy, while
approximately 5% are either Galactic stars or very local galaxies.Comment: Accepted for publication in Ap
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