Analyticity and Gevrey-Class Regularity for the Second-Grade Fluid Equations

We address the global persistence of analyticity and Gevrey-class regularity of solutions to the two and three-dimensional visco-elastic second-grade fluid equations. We obtain an explicit novel lower bound on the radius of analyticity of the solutions that does not vanish as t → ∞, and which is independent of the Rivlin–Ericksen material parameter α. Applications to the damped incompressible Euler equations are also given.     

Reliability and Survival Analysis for Drifting Markov Models: Modeling and Estimation

Methodology and Computing in Applied Probability - In this work we focus on multi-state systems modeled by means of a particular class of non-homogeneous Markov processes introduced in Vergne (Stat...     

Sensitive LC MS quantitative analysis of carbohydrates by Cs<Superscript>+</Superscript> attachment

The development of a sensitive assay for the quantitative analysis of carbohydrates from human plasma using LC/MS/MS is described in this paper. After sample preparation, carbohydrates were cationized by Cs(+) after their separation by normal phase liquid chromatography on an amino based column. Cesium is capable of forming a quasi-molecular ion [M + Cs](+) with neutral carbohydrate molecules in the positive ion mode of electrospray ionization mass spectrometry. The mass spectrometer was operated in multiple reaction monitoring mode, and transitions [M + 133] --> 133 were monitored (M, carbohydrate molecular weight). The new method is robust, highly sensitive, rapid, and does not require postcolumn addition or derivatization. It is useful in clinical research for measurement of carbohydrate molecules by isotope dilution assay.     

An acyclic extension of the braid group

We relate Artin's braid groupB _℞=lim_→B_n to a certain groupF′ ofpl-homeomorphisms of the interval. Namely, there exists a short exact sequence 1→B _∞→A→F′→1 whereH _kA=0,k≥1.     

Thermopower evidence for Wigner crystallization in the insulating phase of two-dimensional GaAs bilayer hole systems

We report on low-temperature thermopower measurements of interacting GaAs bilayer hole systems in the limit of no interlayer tunneling. These systems exhibit a reentrant insulating phase near the many-body quantum Hall state (QHS) at total filling factor ν=1, when both layers have the same density. The diffusion thermopower is expected to diverge as T^-1 in the presence of an energy gap (Wigner crystal) or to vanish in the case of a disordered induced mobility gap. Our results show that, as the temperature is decreased, the diffusion thermopower exhibits a T^-1 dependence in the insulating phase around ν=1. This behavior clearly indicates the opening of an energy gap at low temperature, in agreement with the formation of a pinned Wigner solid. Finally, we report on the T-dependence of the thermopower at ν=1.     

Chelate polymers. IV. siloxanes functionalized with chelating groups derived from hydroxy‐ketones,their metal complexes and some polymers

New ligands were obtained by the reaction of 1,3‐bis(3‐aminopropyl)tetramethyldisiloxane, with acetylacetone, 2,4‐dihydroxybenzophenone and 2,4‐dihydroxyacetophenone. The structures were confirmed by electronic, IR and ¹H NMR spectroscopy and elemental analysis. The change of the refractive index of the siloxanes by their chemical modification was also examined. These compounds were used for coordination of some divalent metals. The ligands and their metal complexes were both soluble in common solvents, such as CHCl₃, dimethylformamide, dimethylsulfoxide, N‐methyl‐2‐pyrrolidone. Some of the bifunctional chelates were inserted into polymeric structures by polycondensation with the diacid chloride of bis(p‐carboxyphenyl)diphenylsilane. Copyright © 2005 John Wiley & Sons, Ltd.     

Transformation products of sclareol IV. Stereochemistry and mass-spectrometric fragmentation of some bicyclohomofarnesane oxides

Summary The stereochemistries of three oxides of the bicyclohomofarnesane series have been established by spectral and chemical methods.Institute of Chemistry, Academy of Sciences of the Moldavian SSR, Kishinev. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 449–454, July–August, 1978.     

Opto-electronic bistable devices in real-time optical information processing

An opto-electronic bistable device using a twisted nematic liquid crystal cell is described. The optical bistability characteristics of this device are used in a new liquid crystal light valve with bistability in cellular array structure. Experimental studies demonstrate the applications of such opto-electronic bistable devices in real-time optical information processing such as intensity limiting for contrast improvement and noise elimination, edge enhancement for pattern recognition, linear and nonlinear optical filtering (in spatial and spectral domains).     

Infinite horizon disturbance attenuation for discrete-time systems. A Popov-Yakubovich approach

It is proved that for the discrete-time linear systems with time-varying coefficients the existence of a controller which simultaneously stabilizes and provides prescribed disturbance attenuation for the resultant closed-loop system, implies the existence of global solutions to several Kalman-Szegö-Popov-Yakubovich systems. It is also proved that this fact is equivalent to the existence of the positive semidefinite stabilizing solutions to corresponding game-theoretic Riccati equations. The family of all controllers with the above mentioned properties is constructed in terms of the solutions to the cited Kalman-Szegö-Popov-Yakubovich systems. The main tool is the generalized Popov-Yakubovich theory which is essentially developed in an operator-theoretic framework.