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Institution

York University

EducationToronto, Ontario, Canada
About: York University is a education organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Population & Politics. The organization has 18899 authors who have published 43357 publications receiving 1568560 citations.


Papers
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Journal ArticleDOI
TL;DR: The fourth edition of the Sloan Digital Sky Survey (SDSS) Quasar catalog as mentioned in this paper contains 77,429 objects, which is an increase of over 30,000 entries since the previous edition; the catalog consists of the objects in the SDSS Fifth Data Release that have luminosities larger than Mi = -22.0, and have highly reliable redshifts.
Abstract: We present the fourth edition of the Sloan Digital Sky Survey (SDSS) Quasar Catalog. The catalog contains 77,429 objects; this is an increase of over 30,000 entries since the previous edition. The catalog consists of the objects in the SDSS Fifth Data Release that have luminosities larger than Mi = -22.0 (in a cosmology with H0 = 70 km s-1 Mpc-1, ΩM = 0.3, and ΩΛ = 0.7), have at least one emission line with FWHM larger than 1000 km s-1 or have interesting/complex absorption features, are fainter than i ≈ 15.0, and have highly reliable redshifts. The area covered by the catalog is ≈5740 deg2. The quasar redshifts range from 0.08 to 5.41, with a median value of 1.48; the catalog includes 891 quasars at redshifts greater than 4, of which 36 are at redshifts greater than 5. Approximately half of the catalog quasars have i < 19; nearly all have i < 21. For each object the catalog presents positions accurate to better than 0.2'' rms per coordinate, five-band (ugriz) CCD-based photometry with typical accuracy of 0.03 mag, and information on the morphology and selection method. The catalog also contains basic radio, near-infrared, and X-ray emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3800-9200 A at a spectral resolution of 2000; the spectra can be retrieved from the public database using the information provided in the catalog. The average SDSS colors of quasars as a function of redshift, derived from the catalog entries, are presented in tabular form. Approximately 96% of the objects in the catalog were discovered by the SDSS.

485 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a survey of the French participation groups in the International Journal of Astronautics and Space Engineering (IJSA), which includes the following participants: Brazilian Participation Group, Brazilian National Astronautic Association (BNAA), Brazil National Astronautical Association (BANAA), German Participation Group (GAP), German Aerospace Center (DLU), French National Institute of Space and Astronauts (INAF), French Government, Agence Nationale de la Recherche (ANR-08-BLAN-0222, ANR-12-
Abstract: PRIN INAF; "Investissements d'Avenir" French Government [ANR-11-IDEX-0001-02]; Agence Nationale de la Recherche [ANR-08-BLAN-0222, ANR-12-BS05-0015]; NASA ADAP [NNX12AE38G]; NSF [1211112, 1515404, AST-1516784]; Alfred P. Sloan Foundation; National Science Foundation; US Department of Energy Office of Science; University of Arizona; Brazilian Participation Group; Brookhaven National Laboratory; Carnegie Mellon University; University of Florida; French Participation Group; German Participation Group; Harvard University; Instituto de Astrofisica de Canarias; Michigan State/Notre Dame/JINA Participation Group; Johns Hopkins University; Lawrence Berkeley National Laboratory; Max Planck Institute for Astrophysics; Max Planck Institute for Extraterrestrial Physics; New Mexico State University; New York University; Ohio State University; Pennsylvania State University; University of Portsmouth; Princeton University; Spanish Participation Group; University of Tokyo; University of Utah; Vanderbilt University; University of Virginia; University of Washington; Yale University; National Aeronautics and Space Administration; Office of Science of the US Department of Energy [DE-AC02-05CH11231]

485 citations

Journal ArticleDOI
TL;DR: Individuals with COPD can be accurately identified in health administrative data, and therefore it may be used to create an unbiased population cohort for surveillance and research, and offers a powerful means of generating evidence to inform strategies that optimize the prevention and management of COPD.
Abstract: Chronic Obstructive Pulmonary Disease (COPD) is a common chronic respiratory disease responsible for significant morbidity and mortality. Population-based health administrative databases provide a powerful and unbiased way of studying COPD in the population, however, their ability to accurately identify patients with this disease must first be confirmed. The objective was to validate population-based health administrative definitions of COPD. Previously abstracted medical records of adults over the age of 35 randomly selected from primary care practices in Ontario, Canada were reviewed by an expert panel to establish if an individual did or did not have a diagnosis of COPD. These reference designations were then linked to each individual's respective health administrative database record and compared with predefine health administrative data definitions of COPD. Concepts of diagnostic test evaluation were used to calculate and compare their test characteristics. The most sensitive health administrative definition of COPD was 1 or more ambulatory claims and/or 1 or more hospitalizations for COPD that yielded a sensitivity of 85.0% (95% confidence interval 77.0 to 91.0) and a specificity of 78.4% (95% confidence interval 73.6 to 82.7). As number of ambulatory claims in the definition increased, sensitivity decreased and specificity increased. Individuals with COPD can be accurately identified in health administrative data, and therefore it may be used to create an unbiased population cohort for surveillance and research. This offers a powerful means of generating evidence to inform strategies that optimize the prevention and management of COPD.

484 citations

Journal ArticleDOI
TL;DR: The results showed a general increment in reading ability for all the bilingual children but a larger advantage for children learning two alphabetic systems, which depends on the relation between the two languages and writing systems.
Abstract: Four groups of children in first grade were compared on early literacy tasks. Children in three of the groups were bilingual, each group representing a different combination of language and writing system, and children in the fourth group were monolingual speakers of English. All the bilingual children used both languages daily and were learning to read in both languages. The children solved decoding and phonological awareness tasks, and the bilinguals completed all tasks in both languages. Initial differences between the groups in factors that contribute to early literacy were controlled in an analysis of covariance, and the results showed a general increment in reading ability for all the bilingual children but a larger advantage for children learning two alphabetic systems. Similarly, bilinguals transferred literacy skills across languages only when both languages were written in the same system. Therefore, the extent of the bilingual facilitation for early reading depends on the relation between the t...

484 citations

Journal ArticleDOI
TL;DR: David Henry and colleagues reevaluate the evidence from observational studies on the cardiovascular risk associated with non-steroidal anti-inflammatory drugs and suggest that these studies should be considered as outliers.
Abstract: Background: Randomised trials have highlighted the cardiovascular risks of non-steroidal anti-inflammatory drugs (NSAIDs) in high doses and sometimes atypical settings. Here, we provide estimates of the comparative risks with individual NSAIDs at typical doses in community settings. Methods and Findings: We performed a systematic review of community-based controlled observational studies. We conducted comprehensive literature searches, extracted adjusted relative risk (RR) estimates, and pooled the estimates for major cardiovascular events associated with use of individual NSAIDs, in different doses, and in populations with low and high background risks of cardiovascular events. We also compared individual drugs in pair-wise (within study) analyses, generating ratios of RRs (RRRs). Thirty case-control studies included 184,946 cardiovascular events, and 21 cohort studies described outcomes in .2.7 million exposed individuals. Of the extensively studied drugs (ten or more studies), the highest overall risks were seen with rofecoxib, 1.45 (95% CI 1.33, 1.59), and diclofenac, 1.40 (1.27, 1.55), and the lowest with ibuprofen, 1.18 (1.11, 1.25), and naproxen, 1.09 (1.02, 1.16). In a sub-set of studies, risk was elevated with low doses of rofecoxib, 1.37 (1.20, 1.57), celecoxib, 1.26 (1.09, 1.47), and diclofenac, 1.22 (1.12, 1.33), and rose in each case with higher doses. Ibuprofen risk was seen only with higher doses. Naproxen was risk-neutral at all doses. Of the less studied drugs etoricoxib, 2.05 (1.45, 2.88), etodolac, 1.55 (1.28, 1.87), and indomethacin, 1.30 (1.19, 1.41), had the highest risks. In pair-wise comparisons, etoricoxib had a higher RR than ibuprofen, RRR=1.68 (99% CI 1.14, 2.49), and naproxen, RRR=1.75 (1.16, 2.64); etodolac was not significantly different from naproxen and ibuprofen. Naproxen had a significantly lower risk than ibuprofen, RRR=0.92 (0.87, 0.99). RR estimates were constant with different background risks for cardiovascular disease and rose early in the course of treatment. Conclusions: This review suggests that among widely used NSAIDs, naproxen and low-dose ibuprofen are least likely to increase cardiovascular risk. Diclofenac in doses available without prescription elevates risk. The data for etoricoxib were sparse, but in pair-wise comparisons this drug had a significantly higher RR than naproxen or ibuprofen. Indomethacin is an older, rather toxic drug, and the evidence on cardiovascular risk casts doubt on its continued clinical use. Please see later in the article for the Editors’ Summary.

484 citations


Authors

Showing all 19301 results

NameH-indexPapersCitations
Dan R. Littman157426107164
Martin J. Blaser147820104104
Aaron Dominguez1471968113224
Gregory R Snow1471704115677
Joseph E. LeDoux13947891500
Kenneth Bloom1381958110129
Osamu Jinnouchi13588586104
Steven A. Narod13497084638
David H. Barlow13378672730
Elliott Cheu133121991305
Roger Moore132167798402
Wendy Taylor131125289457
Stephen P. Jackson13137276148
Flera Rizatdinova130124289525
Sudhir Malik130166998522
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023180
2022528
20212,676
20202,857
20192,426
20182,137