On the well-posedness of coupled forward–backward stochastic differential equations driven by Teugels martingales

We deal with a class of fully coupled forward–backward stochastic differential equations (FBSDEs), driven by Teugels martingales associated with a general Lévy process. Under some assumptions on the derivatives of the coefficients, we prove the existence and uniqueness of a global solution on an arbitrarily large time interval. Moreover, we establish stability and comparison theorems for the solutions of such equations. Note that the present work extends known results proved for FBSDEs driven by a Brownian motion, by using martingale techniques related to jump processes, to overcome the lack of continuity.     

Copper(II)-neocuproine as colour reagent for some biologically active thiols: Spectrophotometric determination of cysteine,penicillamine, glutathione,and 6-mercaptopurine

A new direct spectrophotometric method is described for determination of g/ml concentrations of four biologically important thiols: cysteine, penicillamine, glutathione, and 6-mercaptopurine. The method is based on reaction with copper(II)-neocuproine and subsequent measurement of the Cu(I)-neocuproine produced, at 458 nm. The method has been successfully applied to analysis for these thiols, with a relative standard deviation not exceeding 0.6%.     

An alternative strategy for location tracking

Mobile radio communications raise two major problems. First: a very poor radio link quality. Second: the users' mobility, which requires the management of their position, is resource consuming (especially radio bandwidth). This paper focuses on the second issue and proposes an intelligent method for users locating: the alternative strategy (AS). Our proposal is based on the observation that the mobility behavior of a majority of people can be foretold. If taken into consideration by the system, this characteristic can save signaling messages due to mobility management procedures, leading thus to savings in the system resources. Several versions of the AS are described: a basic version for long term events (i.e., received calls and registrations), and versions with increased memory for short and medium term events. The evaluation of the basic versions was performed using analytic and simulation approaches. It shows that storing the mobility related information brings great savings in system resources when the users have medium or high predictable mobility patterns. More generally speaking, this work points out the fact that the future systems will have to integrate users related information in order: firstly: to provide customized services and secondly: to save system resources. On the other hand, current trends in mobile communications show that adaptive and dynamic system capabilities require that more information to be collected and computed     

Purification and properties of two laccase isoenzymes produced byBotrytis cinerea

Laccases produced by five strains ofBotrytis cinerea were studied. Extraction and purification have been performed in order to compare the enzymatic characteristics both, physicochemically and kinetically. Two strains produced isoenzymes of laccase. These two molecular forms of laccase had different isoelectric points (2.6 and 2.8) and sugar content (86 and 91%). The optimum reactional pH was found to be very similar for both enzymes, in contrast to the temperature sensitivity, which is very different.     

Low frequency Raman mode in smectic liquid crystals near the phase transitions

A low-frequency intermolecular Raman mode at ～ 24 cm^?1 was observed in the solid phase of two related smectic A compounds. This mode shifts abruptly to lower frequency and decreases in intensity at the transition to smectic, while vanishing in the liquid phase. Qualitative interpretation of the results is given.     

A recursive robust filtering approach for 3D registration

This work presents a new recursive robust filtering approach for feature-based 3D registration. Unlike the common state-of-the-art alignment algorithms, the proposed method has four advantages that have not yet occurred altogether in any previous solution. For instance, it is able to deal with inherent noise contaminating sensory data; it is robust to uncertainties caused by noisy feature localisation; it also combines the advantages of both \(L_\infty \) and \(L_2\) norms for a higher performance and a more prospective prevention of local minima. The result is an accurate and stable rigid body transformation. The latter enables a thorough control over the convergence regarding the alignment as well as a correct assessment of the quality of registration. The mathematical rationale behind the proposed approach is explained, and the results are validated on physical and synthetic data.     

High Linearity BiCMOS Multiplier/Transconductor Structures

A new wide-input range BiCMOS analog multiplier is proposed basedon the triode and saturation region operation of the MOS transistors. Thenew circuit can also be reconfigured to operate as a versatile OperationalTransconductance Amplifier, OTA, with independent current bias control for Nstages. The novel design involves the use of attenuators at the input stageto boost the input linear range. It also utilizes a high output impedancesubtractor setup at the output stage to obtain a single-ended output. Thenew circuit is characterized by its large input range, its high linearityand ability to operate at low voltages as well as high frequencies. HSPICEsimulation results of the circuit, using the MOSIS 2 µm processparameters, resulted in an input range of ±4 V (±5 V supply),±1.9 V (±3 V supply) and ±1 V (±2 V supply),with linearity error less than 0.5%. Its usages in certainanalog signal processing applications are also discussed.     

On the existence and uniqueness of solutions for a class of a quasi-variational inequalities to solve reverse-biased semi-conductor devices

Summary This paper discusses existence and uniqueness for solutions of quasi-variational inequalities where the obstacle function w=M(z) satisfies an elliptic equation of the form -exp [kz] exp[–kw]=0. Verifying Joly-Mosco hypotheses for existence appear to depend on an a-priori estimate on w. Thus it was possible to obtain existence and uniqueness for certain cases of the applied biased potentials.     

Development of dynamic headspace-liquid phase microextraction method performed in a home-made extraction vessel for extraction and preconcentration of 1,4-dioxane from shampoo

In the present study, a new, simple, rapid, and environmentally friendly headspace-liquid phase microextraction method followed by gas chromatography–flame ionization detection has been developed for the extraction/preconcentration and determination of 1,4-dioxane from shampoo. The developed procedure is performed in a home-made extraction vessel, connected to a glass vial containing sample and extraction solvent. In this method, an aliquot weight of shampoo is mixed with a binary mixture of n-hexane and dichloromethane (50:50, v/v) as the extractant and the target analyte is extracted during a liquid–liquid extraction procedure. Then a home-made extraction vessel containing a few microliters of a collection/extraction solvent is contacted to a glass vial containing the organic phase obtained from the previous step. By heating 1,4-dioxane is vaporized and enriched in a μL volume of the collection/extraction solvent. Then an aliquot volume of the collected phase is injected into the separation system. The effect of several factors which may influence performance of the method, including kind and volume of the extraction solvents used in both steps, extraction temperature, extraction time, and salt addition were evaluated. Under the optimum extraction conditions, limits of detection and quantification for the target analyte were obtained 0.52 and 1.73 μg kg^?1, respectively. Enrichment factor and extraction recovery were 333 and 89 %, respectively. The method precision was evaluated at a concentration of 25 μg kg^?1 and relative standard deviation was less than 6.9 % for intra-day (n = 6) and inter-day (n = 4) precisions. Finally, the proposed method has been successfully applied in analysis of 1,4-dioxane in different shampoo samples.     

Exploiting Phonon‐Resonant Near‐Field Interaction for the Nanoscale Investigation of Extended Defects

The evolution of wide bandgap semiconductor materials has led to dramatic improvements for electronic applications at high powers and temperatures. However, the propensity of extended defects provides significant challenges for implementing these materials in commercial electronic and optical applications. While a range of spectroscopic and microscopic tools have been developed for identifying and characterizing these defects, such techniques typically offer either technique exclusively, and/or may be destructive. Scattering‐type scanning near‐field optical microscopy (s‐SNOM) is a nondestructive method capable of simultaneously collecting topographic and spectroscopic information with frequency‐independent nanoscale spatial precision (≈20 nm). Here, how extended defects within 4H‐SiC manifest in the infrared phonon response using s‐SNOM is investigated and the response with UV‐photoluminescence, secondary electron and electron channeling contrast imaging, and transmission electron microscopy is correlated. The s‐SNOM technique identifies evidence of step‐bunching, recombination‐induced stacking faults, and threading screw dislocations, and demonstrates interaction of surface phonon polaritons with extended defects. The results demonstrate that phonon‐enhanced infrared nanospectroscopy and spatial mapping via s‐SNOM provide a complementary, nondestructive technique offering significant insights into extended defects within emerging semiconductor materials and devices and thus serves as an important diagnostic tool to help advance material growth efforts for electronic, photonic, phononic, and quantum optical applications.