Institution
University of Arizona
Education•Tucson, Arizona, United States•
About: University of Arizona is a education organization based out in Tucson, Arizona, United States. It is known for research contribution in the topics: Population & Galaxy. The organization has 63805 authors who have published 155998 publications receiving 6854915 citations. The organization is also known as: UA & U of A.
Topics: Population, Galaxy, Stars, Redshift, Star formation
Papers published on a yearly basis
Papers
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TL;DR: The epidemiology and risk factors of burns injuries worldwide are reviewed and it is shown that in high-income countries, burns occur disproportionately to racial and ethnic minorities such that socioeconomic status--more than cultural or educational factors--account for most of the increased burn susceptibility.
760 citations
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TL;DR: In this article, the authors present a new analysis of the transport of cosmic rays in a turbulent magnetic field that varies in all three spatial dimensions using a numerical simulation that integrates the trajectories of an ensemble of test particles from which they obtain diffusion coefficients based on the particle motions.
Abstract: We present a new analysis of the transport of cosmic rays in a turbulent magnetic field that varies in all three spatial dimensions. The analysis utilizes a numerical simulation that integrates the trajectories of an ensemble of test particles from which we obtain diffusion coefficients based on the particle motions. We find that the diffusion coefficient parallel to the mean magnetic field is consistent with values deduced from quasi-linear theory, in agreement with earlier work. The more interesting and less understood transport perpendicular to the average magnetic field is found to be enhanced (above the classical scattering result) by the random walk, or braiding, of the magnetic field. The value of κ⊥ obtained is generally larger than the classical scattering value but smaller than the quasi-linear value. The computed values of κ⊥/κ∥, for a representation of the interplanetary magnetic field, are 0.02-0.04; these values are of the same general magnitude as those assumed in recent numerical simulations of cosmic-ray modulation and transport in the heliosphere, and give reasonable agreement with spacecraft observations of cosmic rays. Some consequences of these results for the interpretation of heliospheric observations are discussed.
760 citations
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TL;DR: Fire scars in giant sequoia were used to reconstruct the spatial and temporal pattern of surface fires that burned episodically through five groves during the past 2000 years, indicating regionally synchronous fire occurrence was inversely related to yearly fluctuations in precipitation and directly related to decadal-to-centennial variations in temperature.
Abstract: Fire scars in giant sequoia [Sequoiadendron giganteum (Lindley) Buchholz] were used to reconstruct the spatial and temporal pattern of surface fires that burned episodically through five groves during the past 2000 years. Comparisons with independent dendroclimatic reconstructions indicate that regionally synchronous fire occurrence was inversely related to yearly fluctuations in precipitation and directly related to decadal-to-centennial variations in temperature. Frequent small fires occurred during a warm period from about A.D. 1000 to 1300, and less frequent but more widespread fires occurred during cooler periods from about A.D. 500 to 1000 and after A.D. 1300. Regionally synchronous fire histories demonstrate the importance of climate in maintaining nonequilibrium conditions.
759 citations
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National Institutes of Health1, University of Würzburg2, University of Groningen3, Bosch4, University of British Columbia5, University of Arizona6, University of Barcelona7, University of Oslo8, St Mary's Hospital9, University of Rochester10, Oregon Health & Science University11, Cleveland Clinic12, University of Nebraska Medical Center13, University of Birmingham14, United States Department of Health and Human Services15
TL;DR: High-throughput RNA sequencing and RNA interference screening is used to discover essential regulatory pathways in Burkitt's lymphoma that cooperate with MYC, the defining oncogene of this cancer.
Abstract: Burkitt's lymphoma (BL) can often be cured by intensive chemotherapy, but the toxicity of such therapy precludes its use in the elderly and in patients with endemic BL in developing countries, necessitating new strategies. The normal germinal centre B cell is the presumed cell of origin for both BL and diffuse large B-cell lymphoma (DLBCL), yet gene expression analysis suggests that these malignancies may use different oncogenic pathways. BL is subdivided into a sporadic subtype that is diagnosed in developed countries, the Epstein-Barr-virus-associated endemic subtype, and an HIV-associated subtype, but it is unclear whether these subtypes use similar or divergent oncogenic mechanisms. Here we used high-throughput RNA sequencing and RNA interference screening to discover essential regulatory pathways in BL that cooperate with MYC, the defining oncogene of this cancer. In 70% of sporadic BL cases, mutations affecting the transcription factor TCF3 (E2A) or its negative regulator ID3 fostered TCF3 dependency. TCF3 activated the pro-survival phosphatidylinositol-3-OH kinase pathway in BL, in part by augmenting tonic B-cell receptor signalling. In 38% of sporadic BL cases, oncogenic CCND3 mutations produced highly stable cyclin D3 isoforms that drive cell cycle progression. These findings suggest opportunities to improve therapy for patients with BL.
757 citations
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TL;DR: The Event Horizon Telescope (EHT) as mentioned in this paper is a very long baseline interferometry (VLBI) array that comprises millimeter and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth.
Abstract: The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth. At a nominal operating wavelength of ~1.3 mm, EHT angular resolution (λ/D) is ~25 μas, which is sufficient to resolve nearby supermassive black hole candidates on spatial and temporal scales that correspond to their event horizons. With this capability, the EHT scientific goals are to probe general relativistic effects in the strong-field regime and to study accretion and relativistic jet formation near the black hole boundary. In this Letter we describe the system design of the EHT, detail the technology and instrumentation that enable observations, and provide measures of its performance. Meeting the EHT science objectives has required several key developments that have facilitated the robust extension of the VLBI technique to EHT observing wavelengths and the production of instrumentation that can be deployed on a heterogeneous array of existing telescopes and facilities. To meet sensitivity requirements, high-bandwidth digital systems were developed that process data at rates of 64 gigabit s^(−1), exceeding those of currently operating cm-wavelength VLBI arrays by more than an order of magnitude. Associated improvements include the development of phasing systems at array facilities, new receiver installation at several sites, and the deployment of hydrogen maser frequency standards to ensure coherent data capture across the array. These efforts led to the coordination and execution of the first Global EHT observations in 2017 April, and to event-horizon-scale imaging of the supermassive black hole candidate in M87.
756 citations
Authors
Showing all 64388 results
Name | H-index | Papers | Citations |
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Simon D. M. White | 189 | 795 | 231645 |
Julie E. Buring | 186 | 950 | 132967 |
David H. Weinberg | 183 | 700 | 171424 |
Richard Peto | 183 | 683 | 231434 |
Xiaohui Fan | 183 | 878 | 168522 |
Dennis S. Charney | 179 | 802 | 122408 |
Daniel J. Eisenstein | 179 | 672 | 151720 |
David Haussler | 172 | 488 | 224960 |
Carlos S. Frenk | 165 | 799 | 140345 |
Jian-Kang Zhu | 161 | 550 | 105551 |
Tobin J. Marks | 159 | 1621 | 111604 |
Todd Adams | 154 | 1866 | 143110 |
Jane A. Cauley | 151 | 914 | 99933 |
Wei Zheng | 151 | 1929 | 120209 |
Daniel L. Schacter | 149 | 592 | 90148 |