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111.
To better understand how the auditory system extracts speech signals in the presence of noise, discrimination thresholds for the second formant frequency were predicted with simulations of auditory-nerve responses. These predictions employed either average-rate information or combined rate and timing information, and either populations of model fibers tuned across a wide range of frequencies or a subset of fibers tuned to a restricted frequency range. In general, combined temporal and rate information for a small population of model fibers tuned near the formant frequency was most successful in replicating the trends reported in behavioral data for formant-frequency discrimination. To explore the nature of the temporal information that contributed to these results, predictions based on model auditory-nerve responses were compared to predictions based on the average rates of a population of cross-frequency coincidence detectors. These comparisons suggested that average response rate (count) of cross-frequency coincidence detectors did not effectively extract important temporal information from the auditory-nerve population response. Thus, the relative timing of action potentials across auditory-nerve fibers tuned to different frequencies was not the aspect of the temporal information that produced the trends in formant-frequency discrimination thresholds. 相似文献
112.
M. Baubillier I.J. Bloodworth G.J. Bossen A. Burns J.N. Carney C.A. Cowan G.F. Cox U. Dore Ph. Gavillet J.B. Kinson F. Levy P.F. Loverre H. McCann M. MacDermott P.J. Negus B.H. Oh M. Pratap R. Zitoun 《Physics letters. [Part B]》1979,89(1):131-135
Backward production of ω(1670) is observed in the reactions K?p→φ+φ?ω0Λ0 and K?p→φ+φ?φ0φ0 for |U'Λ|<1.0 GeV2. The cross section for the ω(1670) →φ+φ?ω0 decay mode is 1.90±0.35 μb for 8.25 GeV/c incident K?. Evidence is presented for the importance of the sequential decay, ω(1670) → Bφ → ωφφ with a branching ratio ω(1670) → Bφ/all ω(1670) → ωφφ=1.0±0.250.00. 相似文献
113.
T. A. Armstrong I. J. Bloodworth J. N. Carney B. R. French B. Ghidini J. B. Kinson V. Lenti A. Palano I. C. Print H. R. Shaylor G. Vassiliadis O. Villalobos Baillie M. E. Votruba G. Zito R. Zitoun WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,34(1):23-31
We have analyzed theK 1 0 K ± π? system in the reactions π+/pp→π+/p(K 1 0 K ± π?)p. A spin-parity analysis of theK 1 0 K ± π? system in the “4C” channel confirms the existence of the 1++ E meson which decays mainly throughK * \(\bar K\) . The data allow the presence of a 0?+ wave at a level of 14% of theE/ι signal. The production ofD andE mesons in the channels where theK 1 0 K ± π? system is produced along with a π0 or π+π? system is suppressed. 相似文献
114.
A. Bellogianni M. Benayoun W. Beusch I. J. Bloodworth J. N. Carney D. Di Bari R. Fini B. R. French B. Ghidini A. Jacholkowski J. Kahane J. B. Kinson A. Kirk K. Knudson V. Lenti Ph. Leruste A. Malamant J. L. Narjoux F. Navach A. Palano E. Quereigh K. Šafařik M. Sené R. Sené M. Stassinaki M. T. Trainor G. Vassiliadis I. Vichou O. Villalobos Baille A. Volte M. F. Vortruba R. Zitoun 《Zeitschrift fur Physik C Particles and Fields》1992,54(4):535-548
Production of oppositely charged particle pairs at largep T is studied, where both particles, are in the central rapidity region within one unit of rapidity and nearby in azimuth. The data sample, which comes fromπ ? Be interactions obtained using the CERN OMEGA spectrometer, contains events with a pair of oppositely charged particles havingp T ≧2 GeV/c recoiling, against a third one withp T ≧1 GeV/c. Our data provide new information on short range correlations involving the production of the nine possible pairs made from (π +,K +,p) and \((\pi ^ - ,K^ - ,\bar p)\) . Comparison with Lund Monte Carlo predictions is made. Apart from proton yields, the model reproduces correctly our data. The main discrepancies observed with protons can be attributed to hard scattering of diquarks from the target nucleons. 相似文献
115.
D H Carney 《Journal of supramolecular structure》1980,13(4):467-478
The localization of thrombin receptors on mouse embryo (ME) cells has been examined by direct fluorescence microscopy using a fluorescein amine-labeled thrombin. Two fluorescein amines, 4-(N-2-aminoethyl thioureal)-fluorescein and 4-(N-5-aminohexyl thioureal)-fluorescein, were synthesized and attached to the carbohydrate moiety of highly purified human alpha-thrombin by periodate oxidation of the carbohydrate and selective reduction of the Schiff's base using sodium cyanoborohydride. Preparations of fluorescent thrombin with from 1 to 4 fluoresceins per molecule of thrombin retained their ability to proteolytically cleave fibrinogen to form fibrin clots, to bind to thrombin receptors on ME cells, and to initiate cell division. After incubating mitogenic concentrations of the fluorescein amine labeled thrombin with ME cells at 4 degrees C, a diffuse fluorescent pattern was observed over the surface of the ME cells. This diffuse pattern was specific: it was not observed on cells from parallel cultures incubated with fluorescent thrombin plus a 20-fold excess of unlabeled thrombin. Thus, thrombin receptors appear to be distributed randomly over the surface of ME cells prior to interaction with thrombin. Increasing the temperature to 37 degrees C following binding at 4 degrees C resulted in a rapid dissociation of the fluorescent pattern from the cells leaving only the autofluorescent vesicles. This result may reflect the unique ability of thrombin to proteolytically cleave its own receptor. 相似文献
116.
Fort DM Ubillas RP Mendez CD Jolad SD Inman WD Carney JR Chen JL Ianiro TT Hasbun C Bruening RC Luo J Reed MJ Iwu M Carlson TJ King SR Bierer DE Cooper R 《The Journal of organic chemistry》2000,65(20):6534-6539
Two new compounds, pycnanthuquinone A (1) and pycnanthuquinone B (2), were isolated from leaves and stems of the African plant, Pycnanthus angolensis (Welw.) Warb (Myristicaceae), by bioassay-guided fractionation of an ethanolic extract using a diabetic mouse model. Pycnanthuquinones A and B are the first representatives of a novel terpenoid-type quinone skeleton, and both compounds possess significant antihyperglycemic activity. 相似文献
117.
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119.
Interferometric synthetic aperture microscopy processing of optical coherence tomography data has been shown to allow computational focusing of en face planes that have traditionally been regarded as out of focus. It is shown that this focusing of the image also produces a defocusing effect in autocorrelation artifacts resulting from Fourier-domain data collection. This effect is verified experimentally and through simulation. 相似文献
120.