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91.
Eva B Holmberg Patricia Doyle Joseph S Perkell Britta Hammarberg Robert E Hillman 《Journal of voice》2003,17(3):269-282
An important clinical issue concerns the efficacy of current voice therapy approaches in treating voice disorders, such as vocal nodules. Much research focuses on finding reliable methods for documentation of treatment results. In this second treatment study of ten patients with vocal nodules, who participated in a behaviorally based voice therapy program, 11 aerodynamic (transglottal air pressure and glottal waveform) and acoustic (spl, f0, and spectrum slope) measures were used. Three pretherapy baseline assessments were carried out, followed by one assessment after each of five therapy phases. Measurements were made of two types of speech materials: Strings of repeated /pae/ syllables and sustained /ae/ phonations in two loudness conditions: comfortable loudness and loud voice. The data were normalized using z-scores, which were based on data from 22 normal subjects. The results showed that the aerodynamic measures reflected the presence of vocal pathology to a higher degree than did the acoustic spectral measures, and they should be useful in studies comparing nodule and normal voice production. Large individual session-to-session variation was found for all measures across pretherapy baseline recordings, which contributed to nonsignificant differences between baseline and therapy data. 相似文献
92.
We have performed extensive small-angle neutron scattering (SANS) diffraction studies of the vortex lattice in single crystal
YNi2B2C for B‖c. High-resolution SANS, combined with a field-oscillation vortex lattice preparation technique, allows us to separate Bragg
scattered intensities from two orthogonal domains and accurately determine the unit cell angle, β. The data suggest that upon increasing field there is a finite transition width where both low- and high-field distorted
hexagonal vortex lattice phases, mutually rotated by 45°, coexist. The smooth variation of diffracted intensity from each
phase through the transition corresponds to a redistribution of populations between the two types of domains. 相似文献
93.
J. E. Koch W. Krieg E. E. Harris R. L. Mitchell F. W. Klingstedt W. H. Dore Erich Schmidt A. W. Schorger P. Klason Bror Holmberg und C. Greaves 《Fresenius' Journal of Analytical Chemistry》1940,119(5-6):237-240
Ohne Zusammenfassung 相似文献
94.
Natalie Holmberg‐Douglas Nicholas P. R. Onuska David A. Nicewicz 《Angewandte Chemie (International ed. in English)》2020,59(19):7425-7429
Expanding the toolbox of C?H functionalization reactions applicable to the late‐stage modification of complex molecules is of interest in medicinal chemistry, wherein the preparation of structural variants of known pharmacophores is a key strategy for drug development. One manifold for the functionalization of aromatic molecules utilizes diazo compounds and a transition‐metal catalyst to generate a metallocarbene species, which is capable of direct insertion into an aromatic C?H bond. However, these high‐energy intermediates can often require directing groups or a large excess of substrate to achieve efficient and selective reactivity. Herein, we report that arene cation radicals generated by organic photoredox catalysis engage in formal C?H functionalization reactions with diazoacetate derivatives, furnishing sp2–sp3 coupled products with moderate‐to‐good regioselectivity. In contrast to previous methods utilizing metallocarbene intermediates, this transformation does not proceed via a carbene intermediate, nor does it require the presence of a transition‐metal catalyst. 相似文献
95.
Modern communication networks often use Internet Protocol routing and the intra-domain protocol OSPF (Open Shortest Path First).
The routers in such a network calculate the shortest path to each destination and send the traffic on these paths, using load
balancing. The issue of survivability, i.e. the question of how much traffic the network will be able to accommodate if components
fail, is increasingly important. We consider the problem of designing a survivable IP network, which also requires determining
the routing of the traffic. This is done by choosing the weights used for the shortest path calculations. 相似文献
96.
97.
Paramagnetic liposomal contrast agents were synthesized and utilized for selective augmentation of T1 MR imaging of the livers of normal Balb/c mice. Amphiphilic gadolinium complexes, which mimic phospholipids, were incorporated into the lamella of small unilamellar liposomes (SUV) such that they become an integral part of its surface. The amphiphilic complexing agents consisted of DTPA reagents in which a pair of alkyl chains of varying lengths are attached via amide linkages. The in vivo lifetimes of the amphiphilic agents were found to be dependent on the chain length of the alkyl groups. 相似文献
98.
Kaj Holmberg 《Computational Optimization and Applications》1995,4(4):293-316
The stochastic transportation problem can be formulated as a convex transportation problem with nonlinear objective function and linear constraints. We compare several different methods based on decomposition techniques and linearization techniques for this problem, trying to find the most efficient method or combination of methods. We discuss and test a separable programming approach, the Frank-Wolfe method with and without modifications, the new technique of mean value cross decomposition and the more well known Lagrangean relaxation with subgradient optimization, as well as combinations of these approaches. Computational tests are presented, indicating that some new combination methods are quite efficient for large scale problems. 相似文献
99.
M. Arbman R. Moberg S. Holmberg U. I. Wahlgren H. O. G. Siegbahn 《International journal of quantum chemistry》1992,41(4):637-651
Experimental and computational results from the study of positive and negative ions in solution are presented. The importance of short-range interactions between ion and solvent is studied with regard to core ionization of the ion. Exchange repulsion is found to be a significant factor in the interpretation of data for both cations and anions. Experimental results are presented for the core ionization of the OH? ion in solution. The data show a strong similarity with corresponding data for the F? ion, resulting in a large negative solvation energy for the final core hole state. The Be2+ ion shows large solvation energies for both ground- and core-ionized states, which is interpreted as due to charge transfer effects between solvent and ion. 相似文献
100.