9 research outputs found
The Chandra Source Catalog
The Chandra Source Catalog (CSC) is a general purpose virtual X-ray
astrophysics facility that provides access to a carefully selected set of
generally useful quantities for individual X-ray sources, and is designed to
satisfy the needs of a broad-based group of scientists, including those who may
be less familiar with astronomical data analysis in the X-ray regime. The first
release of the CSC includes information about 94,676 distinct X-ray sources
detected in a subset of public ACIS imaging observations from roughly the first
eight years of the Chandra mission. This release of the catalog includes point
and compact sources with observed spatial extents <~ 30''. The catalog (1)
provides access to the best estimates of the X-ray source properties for
detected sources, with good scientific fidelity, and directly supports
scientific analysis using the individual source data; (2) facilitates analysis
of a wide range of statistical properties for classes of X-ray sources; and (3)
provides efficient access to calibrated observational data and ancillary data
products for individual X-ray sources, so that users can perform detailed
further analysis using existing tools. The catalog includes real X-ray sources
detected with flux estimates that are at least 3 times their estimated 1 sigma
uncertainties in at least one energy band, while maintaining the number of
spurious sources at a level of <~ 1 false source per field for a 100 ks
observation. For each detected source, the CSC provides commonly tabulated
quantities, including source position, extent, multi-band fluxes, hardness
ratios, and variability statistics, derived from the observations in which the
source is detected. In addition to these traditional catalog elements, for each
X-ray source the CSC includes an extensive set of file-based data products that
can be manipulated interactively.Comment: To appear in The Astrophysical Journal Supplement Series, 53 pages,
27 figure
Statistical Characterization of the Chandra Source Catalog
The first release of the Chandra Source Catalog (CSC) contains ~95,000 X-ray
sources in a total area of ~0.75% of the entire sky, using data from ~3,900
separate ACIS observations of a multitude of different types of X-ray sources.
In order to maximize the scientific benefit of such a large, heterogeneous
data-set, careful characterization of the statistical properties of the
catalog, i.e., completeness, sensitivity, false source rate, and accuracy of
source properties, is required. Characterization efforts of other, large
Chandra catalogs, such as the ChaMP Point Source Catalog (Kim et al. 2007) or
the 2 Mega-second Deep Field Surveys (Alexander et al. 2003), while
informative, cannot serve this purpose, since the CSC analysis procedures are
significantly different and the range of allowable data is much less
restrictive. We describe here the characterization process for the CSC. This
process includes both a comparison of real CSC results with those of other,
deeper Chandra catalogs of the same targets and extensive simulations of
blank-sky and point source populations.Comment: To be published in the Astrophysical Journal Supplement Series (Fig.
52 replaced with a version which astro-ph can convert to PDF without issues.
Interprofessional education through shadowing experiences in multi-disciplinary clinical settings
The World Health Organization has recently added Interprofessional Education (IPE) to its global health agenda recognizing it as a necessary component of all health professionals' education. We suggest mandatory interprofessional shadowing experiences as a mechanism to be used by chiropractic institutions to address this agenda. IPE initiatives of other professions (pharmacy and medicine) are described along with chiropractic. This relative comparison of professions local to our jurisdiction in Ontario, Canada is made so that the chiropractic profession may take note that they are behind other health care providers in implementing IPE
Sequential transcriptome analysis of human liver cancer indicates late stage acquisition of malignant traits
Background & AimsHuman hepatocarcinogenesis is as a multi-step process starting from dysplastic lesions to early carcinomas (eHCC) that ultimately progress to HCC (pHCC). However, the sequential molecular alterations driving malignant transformation of the pre-neoplastic lesions are not clearly defined. This lack of information represents a major challenge in the clinical management of patients at risk.MethodsWe applied next-generation transcriptome sequencing to tumor-free surrounding liver (n=7), low- (n=4) and high-grade (n=9) dysplastic lesions, eHCC (n=5) and pHCC (n=3) from 8 HCC patients with hepatitis B infection. Integrative analyses of genetic and transcriptomic changes were performed to characterize the genomic alterations during hepatocarcinogenesis.ResultsWe report that changes in transcriptomes of early lesions including eHCC were modest and surprisingly homogenous. Extensive genetic alterations and subsequent activation of prognostic adverse signaling pathways occurred only late during hepatocarcinogenesis and were centered on TGFβ, WNT, NOTCH, and EMT-related genes highlighting the molecular diversity of pHCC. We further identify IGFALS as a key genetic determinant preferentially down-regulated in pHCC.ConclusionsOur results define new hallmarks in molecular stratification and therapy options for patients at risk for HCC, and merit larger prospective investigations to develop a modified clinical-decision making algorithm based on the individualized next-generation sequencing analyses
Enraizamento de estacas de azaléia tratadas com concentrações de ANA em diferentes substratos Rooting of azalea cuttings treats with NAA concentrations and differents substrates
De acordo com a necessidade de aumentar a produção de mudas de azaléia por meio da propagação vegetativa, em menor intervalo de tempo, foi proposto estudar os efeitos de diferentes substratos e concentrações de ANA (ácido naftalenoacético). O experimento foi conduzido em esquema fatorial 3X4 com três substratos (areia grossa lavada, casca de arroz carbonizada e húmus) e quatro concentrações de ANA na forma de pó (0; 2,5; 5,0 e 7,5%). Utilizaram-se estacas de 100 mm de comprimento retiradas da porção apical do ramo, sem gema apical e com corte em bisel na parte superior, deixando um par de folhas cortadas ao meio. Essas foram colocadas para enraizar em bandejas de isopor de 128 células, por um período de 90 dias, nas quais avaliaram-se: comprimento, superficie, volume e diâmetro radicular e a porcentagem de estacas enraizadas, sobreviventes, mortas e número de brotos. Pode-se concluir que a maior porcentagem de enraizamento foi obtida no substrato de casca de arroz carbonizada e com ANA na concentração de 5%.<br>In agreement with to enhancement scion production ofRhododendron x simsii Planch trough the vegetative propagation in shorter time, it was intended to study the effects of different substrates and NAA concentration. The experiment was in factorial design 3x4 with three substrates (sand, hush rice and humus) and four NAA concentrations in the powder form (0; 2.5; 5.0 and 7.5%). The cuttings used had 100 mm length without apical meristem with two leaves cut in half. Those were put to rooting in trays of 128 cells, for 90 days in which were evaluated: length, surface, volume and root diameter and percentage of rooted, surviving and dead cuttings and number the buds. It can be conclued that the greatest of rooting was obtained in the substrates hush rice and the 5% of NAA