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Bjorn Fritzell 《Journal of voice》1992,6(2)
Inverse filtering is a noninvasive method of producing a glottogram thought to reflect the vibratory motions of the vocal fold. The flow glottogram provides information related to the type of phonation, the sound pressure level, the regularity of vocal fold vibrations, and to the presence or absence of vocal fold closure. Limited data, speech samples, filter tuning, and lack of unanimity on waveform display and interpretation have contributed to slow application of the techniques to the clinical population. The author argues the technique has utility in both diagnosis and treatment 相似文献
3.
The CD spectra of L-2-methylpyrrolidine, L-prolinol, and their N-methylated derivatives have been determined. As in the 2-substituted piperidines, N-methylation results in an inversion of the sign of the Cotton effects (CE). However, the sign of the long-wavelength CE does not follow the simple helicity rule found for 2-substituted piperidines, since the pyrrolidine ring is itself chiral and makes its own contributions to the observed CE's. The rotational contribution due to pyrrolidine ring chirality appears to be opposite in sign to and larger in magnitude than that due to the 2-substituent in both the secondary and the tertiary amines. 相似文献
4.
E. G. Coffman Jr. Bjorn Poonen Peter Winkler 《Probability Theory and Related Fields》1995,102(1):105-121
Summary Letn random intervalsI
1, ...,I
n be chosen by selecting endpoints independently from the uniform distribution on [0.1]. Apacking is a pairwise disjoint subset of the intervals; itswasted space is the Lebesgue measure of the points of [0,1] not covered by the packing. In any set of intervals the packing with least wasted space is computationally easy to find; but its expected wasted space in the random case is not obvious. We show that with high probability for largen, this best packing has wasted space
. It turns out that if the endpoints 0 and 1 are identified, so that the problem is now one of packing random arcs in a unit-circumference circle, then optimal wasted space is reduced toO(1/n). Interestingly, there is a striking difference between thesizes of the best packings: about logn intervals in the unit interval case, but usually only one or two arcs in the circle case. 相似文献
5.
Bjorn Poonen 《Journal of the American Mathematical Society》1996,9(3):783-812
Let be an algebraically closed field containing which is complete with respect to an absolute value . We prove that under suitable constraints on the coefficients, the series converges to a surjective, open, continuous -linear homomorphism whose kernel is locally compact. We characterize the locally compact sub--vector spaces of which occur as kernels of such series, and describe the extent to which determines the series. We develop a theory of Newton polygons for these series which lets us compute the Haar measure of the set of zeros of of a given valuation, given the valuations of the coefficients. The ``adjoint' series converges everywhere if and only if does, and in this case there is a natural bilinear pairing
which exhibits as the Pontryagin dual of . Many of these results extend to non-linear fractional power series. We apply these results to construct a Drinfeld module analogue of the Weil pairing, and to describe the topological module structure of the kernel of the adjoint exponential of a Drinfeld module.
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Poly(ether amide)s were prepared by polycondensation of 1,13‐diamino‐4,7,11‐trioxatridecane (DTT) with the bisimidazolide or with the bis N‐hydroxysuccinimide ester of sebacic acid. Four different solvents and three different temperatures were compared. The highest molecular weights were obtained with the bisimidazolide in dimethylsulfoxide (DMSO) at 60°C. MALDI‐TOF mass spectra revealed the existence of cyclic oligoamides and polyamides in all samples. The molar fraction of cycles considerably increased with higher molecular weights of the entire sample. The polycondensations were repeated under optimum conditions in the presence of α‐cyclodextrin to prepare polydisperse catenanes consisting of α‐cyclodextrin threaded on cyclic polyamides. Yet, despite broad variation of the reaction conditions, only cylic polyamides free of cyclodextrin were isolated. Furthermore, a pseudorotaxane was prepared from DTT and α‐cyclodetrin and polycondensed with bis‐(4‐chlorophenyl)sebacate. Again, only cyclic polyamides free of cyclodextrin were detectable. 相似文献
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We report spectroscopic evidence for the pressure-induced structural changes in B2O3 glass quenched from melts at pressures up to 6 GPa using solid-state NMR. While all borons are tri-coordinated at 1 atm, the fraction of tetra-coordinated boron increases with pressure, being about 5% and 27% in the B2O3 glass quenched from melts at 2 and 6 GPa, respectively. The fraction of boroxol ring species increases with pressure up to 2 GPa and apparently decreases with further compression up to 6 GPa. Two densification mechanisms are proposed to explain the variation of boron species with pressure. 相似文献
10.
A microfluidic flow injection (microFIA) system was employed for handling and monitoring of cell-released products from living cells immobilised on silicon microchips. The dynamic release of glucose and ethanol produced from sucrose by immobilised Saccharomyces cerevisiae cells was determined using microchip biosensors (micro-biosensors) with either co-immobilised glucose oxidase-horseradish peroxidase (GOX-HRP), or alcohol oxidase-horseradish peroxidase (AOX-HRP), catalysing a series of reactions ending up with chemiluminescence (CL) generated from HRP-catalysed oxidation of luminol in presence of p-iodophenol (PIP). The yeast cells were attached by first treating them with polyethylenimine (PEI) followed by adsorption to the microchip surface. The cell loss during assaying was evaluated qualitatively using scanning electron microscopy (SEM), showing that no cells were lost after 35 min liquid handling of the cell chip at 10 microl min(-1). The enzymes were immobilised on microchips via PEI-treatment followed by glutaraldehyde (GA) activation. The GOX-HRP micro-biosensors could be used during five days without any noticeable decrease in response, while the AOX-HRP micro-biosensors showed continuously decreasing activity, but could still be used employing calibration correction. The glucose and ethanol released from the immobilised yeast chips were quantitatively monitored, by varying the incubation time with sucrose, showing the possibilities and advantages of using a microfluidic system set-up for cell-based assays. 相似文献