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81.
Rønne FM Dau T Harte J Elberling C 《The Journal of the Acoustical Society of America》2012,131(5):3903-3913
A quantitative model is presented that describes the formation of auditory brainstem responses (ABRs) to tone pulses, clicks, and rising chirps as a function of stimulation level. The model computes the convolution of the instantaneous discharge rates using the "humanized" nonlinear auditory-nerve model of Zilany and Bruce [J. Acoust. Soc. Am. 122, 402-417 (2007)] and an empirically derived unitary response function which is assumed to reflect contributions from different cell populations within the auditory brainstem, recorded at a given pair of electrodes on the scalp. It is shown that the model accounts for the decrease of tone-pulse evoked wave-V latency with frequency but underestimates the level dependency of the tone-pulse as well as click-evoked latency values. Furthermore, the model correctly predicts the nonlinear wave-V amplitude behavior in response to the chirp stimulation both as a function of chirp sweeping rate and level. Overall, the results support the hypothesis that the pattern of ABR generation is strongly affected by the nonlinear and dispersive processes in the cochlea. 相似文献
82.
83.
Karl-Georg Wönne und O. Fuchs 《Fresenius' Journal of Analytical Chemistry》1975,273(3):209-210
Ohne Zusammenfassung 相似文献
84.
K. Panagiotidis R. Glaum J. Schmedt auf der Günne W. Hoffbauer H. Grzel 《无机化学与普通化学杂志》2005,631(12):2371-2376
Synthesis, Crystal Structure and Spectroscopical Characterization of Palladium(II)‐Diphosphate Pd2P2O7 Pd2P2O7 is synthesized by heating (Tmax = 500 °C) stoichiometric amounts of PdO and phosphoric acid. Using chemical vapour transport experiments (850 °C → 750 °C, addition of PdCl2) Pd2P2O7 was crystallized. Pd2P2O7 adopts its own structure type (C 2/c (No. 15), Z = 4, a = 13,151(2) Å, b = 5,172(1) Å, c = 8,139(1) Å, β = 97,52(1)°, 1160 independent reflections, 55 variables, R1 = 0,021 and wR2 = 0,050). Square‐planar [PdO4]‐units are linked by diphosphate‐groups generating a 3D framework. Within this framework ribbons may be distinguished. Thus Pd2P2O7 might be described as palladium(II)‐[diphosphatopalladate(II)]. The results of various spectroscopic measurements (IR, Raman, UV/VIS, 31P‐MAS‐NMR) are reported and discussed within the context of the crystal structure. 相似文献
85.
Wenyu Li Dr. Matthias Adlung Qianyun Zhang Prof. Dr. Claudia Wickleder Prof. Dr. Jörn Schmedt auf der Günne 《Chemphyschem》2019,20(23):3245-3250
Crystalline powders of Ln3+ doped LaPO4 (Ln=Nd, Gd, Dy, Ho, Er, Tm, Yb) have been synthesized to serve in a case study for linking doping homogeneity as determined by NMR to luminescent properties. Samples obtained via different synthesis methods act as examples of homo- and inhomogeneous doping. The sample quality was verified by X-ray diffraction. The homogeneously doped samples show improved luminescent properties in terms of brightness and lifetime which is consistent with the interpretation that, NMR visibility curves probe the distribution of paramagnetic dopants on a similar length scale as necessary for an efficient energy transfer in crystalline phosphors i. e. between sensitizers and activators, and to killer sites. Thus “NMR homogeneity” as observed by visibility curves may serve as a tool to optimize luminescent materials. 相似文献
86.
Schmedt auf der Günne J Beck J Hoffbauer W Krieger-Beck P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(15):4429-4440
In this contribution we present a study of the structure of amorphous poly(carbonsuboxide) (C3O2)x by 13C solid-state NMR spectroscopy supported by infrared spectroscopy and chemical analysis. Poly(carbonsuboxide) was obtained by polymerization of carbonsuboxide C3O2, which in turn was synthesized from malonic acid bis(trimethylsilylester). Two different 13C labeling schemes were applied to probe inter- and intramonomeric bonds in the polymer by dipolar solid-state NMR methods and also to allow quantitative 13C MAS NMR spectra. Four types of carbon environments can be distinguished in the NMR spectra. Double-quantum and triple-quantum 2D correlation experiments were used to assign the observed peaks using the through-space and through-bond dipolar coupling. In order to obtain distance constraints for the intermonomeric bonds, double-quantum constant-time experiments were performed. In these experiments an additional filter step was applied to suppress contributions from not directly bonded 13C,13C spin pairs. The 13C NMR intensities, chemical shifts, connectivities and distances gave constraints for both the polymerization mechanism and the short-range order of the polymer. The experimental results were complemented by bond lengths predicted by density functional theory methods for several previously suggested models. Based on the presented evidence we can unambiguously exclude models based on gamma-pyronic units and support models based on alpha-pyronic units. The possibility of planar ladder- and bracelet-like alpha-pyronic structures is discussed. 相似文献
87.
88.
The energy minimum of a linear chain of four hydrogen atomsH4 was investigated in dependence on the inner atomic distancea and the ?surface” distanceb. An energy minimum was obtained for somea ≠b. Some comments of methodological character are added. 相似文献
89.
Jaebong Jang Ciric To Dries J. H. De Clercq Eunyoung Park Charles M. Ponthier Bo Hee Shin Mierzhati Mushajiang Radosaw P. Nowak Eric S. Fischer Michael J. Eck Pasi A. Jnne Nathanael S. Gray 《Angewandte Chemie (International ed. in English)》2020,59(34):14481-14489
Targeting epidermal growth factor receptor (EGFR) through an allosteric mechanism provides a potential therapeutic strategy to overcome drug‐resistant EGFR mutations that emerge within the ATP binding site. Here, we develop an allosteric EGFR degrader, DDC‐01‐163, which can selectively inhibit the proliferation of L858R/T790M (L/T) mutant Ba/F3 cells while leaving wildtype EGFR Ba/F3 cells unaffected. DDC‐01‐163 is also effective against osimertinib‐resistant cells with L/T/C797S and L/T/L718Q EGFR mutations. When combined with an ATP‐site EGFR inhibitor, osimertinib, the anti‐proliferative activity of DDC‐01‐163 against L858R/T790M EGFR‐Ba/F3 cells is enhanced. Collectively, DDC‐01‐163 is a promising allosteric EGFR degrader with selective activity against various clinically relevant EGFR mutants as a single agent and when combined with an ATP‐site inhibitor. Our data suggests that targeted protein degradation is a promising drug development approach for mutant EGFR. 相似文献