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41.
Schimmel O van de Par S Breebaart J Kohlrausch A 《The Journal of the Acoustical Society of America》2008,124(2):1130-1145
The ability to segregate two spectrally and temporally overlapping signals based on differences in temporal envelope structure and binaural cues was investigated. Signals were a harmonic tone complex (HTC) with 20 Hz fundamental frequency and a bandpass noise (BPN). Both signals had interaural differences of the same absolute value, but with opposite signs to establish lateralization to different sides of the medial plane, such that their combination yielded two different spatial configurations. As an indication for segregation ability, threshold interaural time and level differences were measured for discrimination between these spatial configurations. Discrimination based on interaural level differences was good, although absolute thresholds depended on signal bandwidth and center frequency. Discrimination based on interaural time differences required the signals' temporal envelope structures to be sufficiently different. Long-term interaural cross-correlation patterns or long-term averaged patterns after equalization-cancellation of the combined signals did not provide information for the discrimination. The binaural system must, therefore, have been capable of processing changes in interaural time differences within the period of the harmonic tone complex, suggesting that monaural information from the temporal envelopes influences the use of binaural information in the perceptual organization of signal components. 相似文献
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Dyer HE Huijser S Schwarz AD Wang C Duchateau R Mountford P 《Dalton transactions (Cambridge, England : 2003)》2008,(1):32-35
The reaction of Sm{N(SiMe3)2}3 with the bis(phenol)amines H2O2N(R) (H2O2N(R) = RCH2CH2N(2-HO-3,5-C6H2(t)Bu2)2; R = OMe, NMe2 or Me) gave exclusively zwitterions Sm(O2N(R))(HO2N(R)). For R = OMe or NMe2 these were efficient catalysts for the ring-opening polymerisation of epsilon-caprolactone and D,L-lactide with a tendency to form cyclic esters; in contrast, no polymerisation was observed for R = Me. 相似文献
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Yang XL Kapoor M Otero FJ Slike BM Tsuruta H Frausto R Bates A Ewalt KL Cheresh DA Schimmel P 《Chemistry & biology》2007,14(12):1323-1333
Disease-causing mutations occur in genes for aminoacyl tRNA synthetases. That some mutations are dominant suggests a gain of function. Native tRNA synthetases, such as tyrosyl-tRNA synthetase (TyrRS) and tryptophanyl-tRNA synthetase, catalyze aminoacylation and are also procytokines that are activated by natural fragmentation. In principle, however, gain-of-function phenotypes could arise from mutational activation of synthetase procytokines. From crystal structure analysis, we hypothesized that a steric block of a critical Glu-Leu-Arg (ELR) motif in full-length TyrRS suppresses the cytokine activity of a natural fragment. To test this hypothesis, we attempted to uncover ELR in the procytokine by mutating a conserved tyrosine (Y341) that tethers ELR. Site-specific proteolytic cleavage and small-angle X-ray scattering established subtle opening of the structure by the mutation. Strikingly, four different assays demonstrated mutational activation of cytokine functions. The results prove the possibilities for constitutive gain-of-function mutations in tRNA synthetases. 相似文献
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H. Beyer M. Müller T. Schimmel 《Applied Physics A: Materials Science & Processing》1999,68(2):163-166
Received: 27 March 1998 相似文献
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Saskia Mioduszewski 《The European Physical Journal C - Particles and Fields》2009,61(4):741-745
Results on high-p
T
probes shown at the Hard Probes 2008 Conference are summarized, with an appreciation of the improvements in precision of
the measurements and experimental techniques since the beginning of RHIC operation. Particular attention is given to the latest
measurements of the nuclear modification factor of identified particles, photon-hadron correlation measurements, and full
jet reconstruction. 相似文献
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