Limiting Velocity and Dispersion Law of Domain Walls in Ferrimagnets Close to the Spin Compensation Point

JETP Letters - The motion of domain walls in GdFeCo-type ferrimagnets near the point of compensation of sublattice spins s1 and s2, when the effects of the exchange increase in the limiting wall...     

Some aerodynamic and acoustic characteristicsof acute laryngitis

The purpose of the present study was to describe the effects ofacute laryngitis on some aerodynamic, acoustic, and perceptual measures. Eleven subjects with diagnosed acute laryngitis due to upper respiratory infection were recorded during a laryngitic episode and 1 week to 10 days after amelioration of the laryngitic condition. Fundamental frequency values, collapsed across the five vowels, were significantly reduced in the laryngitic compared with the normal speaking condition. The decrease in fundamental frequency associated with acute laryngitis suggests an increase in the mass of the vocal folds. In addition, aerodynamic values differed significantly for the laryngitic condition compared with the normal speaking condition, suggesting the presence of laryngeal hypofunction. Perceptual data indicated that speakers in the laryngitic condition were judged to have a hoarse voice when compared with the normal speaking condition.     

Robust Group Synchronization via Cycle-Edge Message Passing

We propose a general framework for solving the group synchronization problem, where we focus on the setting of adversarial or uniform corruption and sufficiently small noise. Specifically, we apply a novel message passing procedure that uses cycle consistency information in order to estimate the corruption levels of group ratios and consequently solve the synchronization problem in our setting. We first explain why the group cycle consistency information is essential for effectively solving group synchronization problems. We then establish exact recovery and linear convergence guarantees for the proposed message passing procedure under a deterministic setting with adversarial corruption. These guarantees hold as long as the ratio of corrupted cycles per edge is bounded by a reasonable constant. We also establish the stability of the proposed procedure to sub-Gaussian noise. We further establish exact recovery with high probability under a common uniform corruption model.

     

NMR ANALYSES OF TRYPTOPHAN-8-METHOXYPSORALEN PHOTOREACTION PRODUCTS FORMED IN THE PRESENCE OF OXYGEN

Proton-made spectroscopy was performed on solutions of l -tryptophan and 8-mcthoxypsoralen (8-MOP) in either D₂O or DMSO-d₆ in the presence of oxygen before and after irradiation with 360 nm monochromatic light. Irradiation results in the loss of hydrogen atoms at the 3. 4 and 4'. 5' positions of 8-MOP and at the indole C₂ position of tryptophan. Changes in the aliphatic regions of the spectra also occur with irradiation. It is postulated that generation of photoreaction products between 8-MOP and tryptophan involves the 3.4 and 4'.5' positions of 8-MOP and the imidazole moiety of tryptophan.
Reprint requests to: Dr J. Megaw, Laboratory for Ophthalmic Research, Emory University School of Medicine, Atlanta. Georgia 30322. USA.     

FLUORESCENCE LIFETIMES OF OCULAR LENS CHROMOPHORES

Abstract— Fluorescence lifetimes are reported for intact human lenses in vitro. Two spectral regions were investigated: The first was excited at 296nm and detected at 332 or 370nm and corresponds to emission from tryptophan residues in the lens proteins. The second spectral region was excited at 359 nm and detected at 435 nm and corresponds to non-tryptophan 'fluorogen' fluorescence. The latter displayed a constant lifetime, 3.8 ns, independent of the anatomical part of the lens excited. This value was compared with measured lifetimes for some model fluorogens. The tryptophan fluorescence lifetime (332 nm detection) was found to vary from 1.8 to 2.8 ns depending on the anatomical part of the lens excited.     

New reactions of sulphur dichloride with olefines

The interaction between SCl₂ and adamantylideneadamantane produces epithiocompounds $\text{2}$ and $\text{3}$ or polychloroadamantylideneadamantanes $\text{4}$–$\text{7}$ depending upon conditions. The structure of $\text{3}$ was determined by X-ray analysis.     

Reactions of sulfur halides with unsaturated compounds. 26. Reactions of sulfur dichloride with tricyclo[4.2.2.02,5]deca-3,7-dienes and tricyclo[4.2.2.02,5]deca-3,7,9-trienes. Synthesis of compounds with a novel thiaskeletal structure

Addition of sulfur dichloride to tricyclo[4.2.2.0^{2, 5}]deca-3,7-dienes and tricyclo[4.2.2.0^2,5] deca-3,7,9-trienes is accompanied by intramolecular cyclization to give high yields of adducts with the novel thiaskeletal 7-thiatetracyclo[4.2.2.0^4,8.0^5,10]undecane structure. In the reaction of SCl₂ with the 2,3-endo, endo-diester (V), intramolecular cyclization is accompanied by lactonization, to give quantitative yields of the thiaskeletal chlorolactone (X). The structure of the latter compounds was established by x-ray diffraction examination.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 858–864, April, 1990.For previous commmunication see [1].     

Complex dynamics and bifurcations in a Hamiltonian system having a transversal homoclinic orbit to a saddle focus

A Hamiltonian system having a saddle-focus singular point with a transversal homoclinic orbit is considered. The bifurcations that occur upon a variation of the Hamiltonian are studied. Reconstructions of a symbolic system describing the hyperbolic set are investigated. Bifurcations linked with the appearance of Smale horseshoes are pointed out. The results are applied to a system determining traveling-wave solutions of the Landau-Lifshitz equation. Multisolitons with any number of humps can exist.     

Breakdown of symmetry in reversible systems

We review results on local bifurcations of codimension 1 in reversible systems (flows and diffeomorphisms) which lead to the birth of attractor-repeller pairs from symmetric equilibria (for flows) or periodic points (for diffeomorphisms).