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71.
72.
Inter-helix distances in lysophospholipid micelle-bound alpha-synuclein from pulsed ESR measurements
Borbat P Ramlall TF Freed JH Eliezer D 《Journal of the American Chemical Society》2006,128(31):10004-10005
We demonstrate the use of pulsed ESR spectroscopy to measure intramolecular distances in the Parkinson's disease-associated protein alpha-synuclein bound to detergent and lysophospholipid micelles. We show that the inter-helical separation between the two helices formed upon binding to micelles is dependent on micelle composition, with micelles formed from longer acyl chains leading to an increased splaying of the two helices. Our data suggest that the topology of alpha-synuclein is not strongly constrained by the linker region between the two helices and instead depends on the geometry of the surface to which the protein is bound. 相似文献
73.
Aronoff JM Freed DJ Fisher LM Pal I Soli SD 《The Journal of the Acoustical Society of America》2012,131(5):EL382-EL387
Bilateral cochlear implant patients are unable to localize as well as normal hearing listeners. Although poor sensitivity to interaural time differences clearly contributes to this deficit, it is unclear whether deficits in terms of interaural level differences are also a contributing factor. In this study, localization was tested while manipulating interaural time and level cues using head-related transfer functions. The results indicate that bilateral cochlear implant users' ability to localize based on interaural level differences is actually greater than that of untrained normal hearing listeners. 相似文献
74.
This paper presents reactions in which the putative cationic intermediate in the Morin rearrangement is trapped by aromatic carbon nucleophiles (indoles and furans). For example, reaction of sulfoxide 27 with trifluoroacetic acid in chloroform provides, among other products, indole 29 and indoline 30. The indoline was shown to be in equilibrium with the nine-membered ring bridged indole 31. Other examples of Morin rearrangement-trapping reactions are presented, and mechanisms for these transformations are proposed. 相似文献
75.
用真空电弧熔炼法制备了Ce2Co17-xMx(M=Ga,Al和Si)化合物。通过X射线衍射和磁性测量手段,研究了非磁性替代原子Ga,Al和Si的加入对Ce2Co17化合物的剧里温度和饱和磁化强度的影响,其中Si在Ce2Co17化合物中的固溶度最小,并使居里温度和饱和磁化强度下降幅度最大。 相似文献
76.
本文考虑广义BBM方程的初值问题,建立了方程的有理Chebyshev谱格式,给出了谱格式的误差估计,并证明了原问题和近似问题所生成的算子半群分别具有整体吸引子A和AN,且AN关于A 是上半连续的. 相似文献
77.
Time integration of the non-linear Galerkin method 总被引:1,自引:0,他引:1
e-mail: bosco{at}mac.cie.uva.es, frutos@mac.cie.uva.es Numerical tests are presented that, for the Kuramoto-Sivashinskyand a reaction-diffusion equation, compare the non-linear Galerkinmethod with standard pseudospectral and pure spectral Galerkindiscretizations. The results show that, for these problems,the non-linear Galerkin method is not competitive with eitherpure spectral Galerkin or pseudospectral discretizations. 相似文献
78.
RIVERA JAIME E. MU$$$OZ; DE LACERDA OLIVEIRA MILTON 《IMA Journal of Applied Mathematics》1997,58(1):71-82
We consider the unilateral problem for the thermoelastic equationand we show that the solution decays exponentially to zero astime goes to infinity; that is, denoting by E(t) the first-orderenergy of the system, we show that positive constants C and exist which satisfy E(t)CE(0)e$$$. 相似文献
79.
The fragility of polymeric glass-forming liquids is calculated as a function of molecular structural parameters from a generalized entropy theory of polymer glass-formation that combines the Adam-Gibbs (AG) model for the rate of structural relaxation with the lattice cluster theory (LCT) for polymer melt thermodynamics. Our generalized entropy theory predicts the existence of distinct high and low temperature regimes of glass-formation that are separated by a thermodynamically well-defined crossover temperature T(I) at which the product of the configurational entropy and the temperature has an inflection point. Since the predicted temperature dependence of the configurational entropy and structural relaxation time are quite different in these temperature regimes, we introduce separate definitions of fragility for each regime. Experimentally established trends in the fragility of polymer melts with respect to variations in polymer microstructure and pressure are interpreted within our theory in terms of the accompanying changes in the chain packing efficiency. 相似文献
80.