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A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the(More)
Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed(More)
Edge detection is an important, but difficult, step in quantitative ultrasound (US) image analysis. In this paper, we present a new textural approach for detecting a class of edges in US images; namely, the texture edges with a weak regional mean gray-level difference (RMGD) between adjacent regions. The proposed approach comprises a vision model-based(More)
Debt initial public offerings ~IPOs! represent a major shift in a firm's financing policy by both extending debt maturity and altering the public-private debt mix. In contrast to findings for seasoned debt offerings, we document a significantly negative stock price response to debt IPO announcements. This result is consistent with debt maturity and debt(More)
A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200  GeV the positron(More)
OBJECTIVE To compare three methods of computing the national requirements for otolaryngologists in 1994 and 2010. DATA SOURCES Three large HMOs, a Delphi panel, the Bureau of Health Professions (BHPr), and published sources. STUDY DESIGN Three established methods of computing requirements for otolaryngologists were compared: managed care,(More)
Radio resources in wireless communication systems, implementing different multiple access techniques, must be wisely managed. This perspective is pivotal since the variations in propagation channel are very fast. This complexity in the cellular system periodically contributes to different interference levels, high or low, resulting in the degradation of the(More)
The design of potent protein kinase C (PK-C) ligands with low nanomolar binding affinities was accomplished by the combined use of pharmacophore- and receptor-guided approaches based on the structure of the physiological enzyme activator, diacylglycerol (DAG). Earlier use of the former approach, which was based on the structural equivalence of DAG and(More)
Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the(More)
The agency-cost-based hypothesis predicts that dividend payout is inversely related to the degree of institutional ownership. By contrast, under the tax-based hypothesis, dividend payout is predicted to be positively associated with institutional ownership. Using the Tobit analysis, we examine the relationship between institutional ownership and corporate(More)