1,169 research outputs found

    Green Economy

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    Finding Faith: Ghana, the Netherlands, and my Year Abroad

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    Sounds in noise: Behavioral and neural studies of illusory continuity and discontinuity

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    ability to parse an auditory scene into meaningful components varies greatly between individuals; some are able to parse out and write down competing musical pieces while others struggle to understand each word whenever they have to converse in a noisy environment. Using a simple discrimination task, healthy, normally-heari ng adult participants were asked to judge whether a pure tone (with or without amplitude modulation) was continuous or contained a gap. One quarter of the participants consistently heard a gap when none was present, if the tone was accompanied by a higher-frequency noise burst with a lower edge beginning one octave away from the tone (that did not have any energy overlapping the tone). This novel form of informational masking (perceptual interference between components with non-overlapping sound energy) was named 'illusory auditory discontinuity\u2019. The phenomenon appears to reflect natural differences in auditory processing rather than differences in decision-making strategies because: (1) susceptibility to illusory discontinuity correlates with individual differences in auditory streaming (measured using a classical ABA sequential paradigm); and (2) electroencephalographic responses elicited by tones overlaid by short noise bursts (when these sounds are not the focus of attention) are significantly correlated with the occurrence of illusory auditory discontinuity in both an early event-related potential (ERP) component (40-66 ms), and a later ERP component (270-350 ms) after noise onset. Participants prone to illusory discontinuity also tended not to perceive the \u2018auditory continuity illusion\u2019 (in which a tone is heard continuing under a burst of noise centered on the tone frequency that completely masks it) at short noise durations, but reliably perceived the auditory continuity illusion at longer noise durations. These results suggest that a number of attributes describing how individuals differentially parse complex auditory scenes are related to individual differences in two potentially independent attributes of neural processing, reflected here by EEG waveform differences at ~50 msec and ~300 msec after noise onset. Neural correlates of the auditory continuity illusion were also investigated by adjusting masker loudness, so that when listeners were given physically identical stimuli, they correctly detected the gap in a target tone on some trials, while on other trials they reported the tone as continuous (experiencing illusory continuity). High er power of low-frequency EEG activity (in the delta-theta range, <6 Hz) was observed prior to the onset of tones that were subsequently judged as discontinuous, with no other consistent EEG differences found after the onset of tones. These data suggest that the occurrence of the continuity illusion may depend on the brain state that exists immediately before a trial begins

    Seismic anisotropy of Precambrian lithosphere : Insights from Rayleigh wave tomography of the eastern Superior Craton

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    The seismic data used in this study are freely available from the CNDC (Canadian National Data Centre for Earthquake Seismology and Nuclear Explosion Monitoring) and IRIS DMC (Data Management Center) via their data request tools. The Leverhulme Trust (grant RPG-2013-332) and National Science Foundation are acknowledged for financial support. L.P. is supported by Janet Watson Imperial College Department Scholarship and the Romanian Government Research Grant NUCLEU. F.D. is supported by NSERC through the Discovery Grants and Canada Research Chairs program. We also thank two anonymous reviewers and the Associate Editor for insightful comments that helped improve the manuscript.Peer reviewedPublisher PD

    Прогнозирование объема товарооборота между Республикой Беларусь и Китаем на основе корреляционно-регрессионного анализа

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    This paper researches the factors that affect the international trade between Belarus and China, analyzes their changes, and determines the main factors. On this basis, it analyzes the main trends and forecasts of the international trade between the countries under study.Определен перечень факторов, которые оказывают влияние на объем торговли между Республикой Беларусь и Китаем. На основе статистических данных выполнен анализ их изменения, выявлены наиболее важные факторы и установлены роль и направление влияния на взаимную торговлю указанных факторов. Проведены анализ основных тенденций и прогнозирование изменения товарооборота между Республикой Беларусь и Китаем

    Pair creation and plasma oscillations

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    We describe aspects of particle creation in strong fields using a quantum kinetic equation with a relaxation-time approximation to the collision term. The strong electric background field is determined by solving Maxwell's equation in tandem with the Vlasov equation. Plasma oscillations appear as a result of feedback between the background field and the field generated by the particles produced. The plasma frequency depends on the strength of the initial background field and the collision frequency, and is sensitive to the necessary momentum-dependence of dressed-parton masses.Comment: 11 pages, revteX, epsfig.sty, 5 figures; Proceedings of 'Quark Matter in Astro- and Particlephysics', a workshop at the University of Rostock, Germany, November 27 - 29, 2000. Eds. D. Blaschke, G. Burau, S.M. Schmid
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