Post-processing synchronization and characterization of generated signals by a repetitive Marx generator

In the present paper, a new approach was developed for solving the problem of time synchronization of a set of signals obtained by different measurement techniques without a common trigger. The recorded signals were the result of sparks and bursts generated by a repetitive Marx generator. A thermal imaging camera, a high speed camera and an audio recorder were used to obtain the necessary data for synchronization and characterization. Moreover, a piezoelectric sensor was applied for shock waves characterization during the early stages of bursts. In the first place, different data with evident time shifts were acquired. Then, A set of simple operations such as maximum selection and localization, threshold comparison, Euclidean distance calculation and minimization were employed for signal analysis and pattern matching to ensure a good data synchronization, which allowed a detailed analysis of the phenomenon in the end.     

Comparison of comet assay parameters for estimation of genotoxicity by sum of ranking differences

The genotoxic potential of waters in six rivers and reservoirs from Serbia was monitored in different tissues of chub (Squalius cephalus L. 1758) with the alkaline comet assay. The comet assay, or single-cell gel electrophoresis, has a wide application as a simple and sensitive method for evaluating DNA damage in fish exposed to various xenobiotics in the aquatic environment. Three types of cells, erythrocytes, gill cells, and liver cells, were used for assessing DNA damage. Images of randomly selected cells were analyzed with a Leica fluorescence microscope and image analysis by software (Comet Assay IV Image analysis system, PI, UK). Three parameters (tail length—l, tail intensity—i, and Olive tail moment—m) were analyzed on 1,700 nuclei per cell type. The procedure for sum of ranking differences (SRD) was implemented to compare different types of cells and different parameters for estimation of DNA damage. Regarding our nine different estimations of genotoxicity: tail length, intensity, and moment in erythrocytes (rel, rei, rem), liver cells (rll, rli, rlm), and gill cells (rgl, rgi, rgm), the SRD procedure has shown that the Olive tail moment and tail intensity are (almost) equally good parameters; the SRD value was lower for the tail moment and tail intensity than for tail length in the case of all types of cells. The least reliable parameter was rel; close to the borderline case were rei, rll, and rgl (～5 % probability of random ranking).

Immobilization of modified penicillin G acylase on Sepabeads carriers

An approach to stable covalent immobilization of chemically modified penicillin G acylase from Escherichia coli on Sepabeads® carriers with high retention of hydrolytic activity and thermal stability is presented. The two amino-activated polymethacrylate particulate polymers with different spacer lengths used in the study were Sepabeads® EC EA and Sepabeads® EC HA. The enzyme was first modified by cross-linking with polyaldehyde derivatives of starch in order to provide it with new useful functions. Such modified enzyme was then covalently immobilized on amino supports. The method seems to provide a possibility to couple the enzyme without risking a reaction at the active site which might cause the loss of activity. Performances of these immobilized biocatalysts were compared with those obtained by the conventional method with respect to activity and thermal stability. The thermal stability study shows that starch-PGA immobilized on Sepabeads EC-EA was almost 4.5-fold more stable than the conventionally immobilized one and 7-fold more stable than free non-modified PGA. Similarly, starch-PGA immobilized on Sepabeads EC-HA was around 1.5- fold more stable than the conventionally immobilized one and almost 9.5-fold more stable than free non-modified enzyme.     

Indirect optical crosstalk reduction by highly-doped backside layer in single-photon avalanche diode arrays

A method of reducing indirect optical crosstalk in single-photon avalanche diode arrays is investigated by TCAD simulations. The reduction is accomplished by taking advantage of an enhanced optical absorption in a highly-doped Si layer on the backside of the wafer. A simulation environment was developed to give information about optical crosstalk by incorporating the experimental optical constants of the materials constituting the crosstalk-reduction layer. It is shown that the indirect optical crosstalk is greatly reduced by increasing the thickness and doping of the layer. A crosstalk reduction of 5 orders of magnitude is gained with addition of 1-μm-thick \(\hbox {PureB}/\upalpha \hbox {-Si}\) stack for the array processed on a p-type substrate, while the same reduction is achieved with a 1-μm-thick highly-doped Si layer (As, \(1.1\times 10^{20}\, \hbox {cm}^{-3}\)) for an array processed on an n-type substrate.     

Enzyme-catalyzed cascade synthesis of hydroxyiminoacetamides

In order to synthesize N-(3-azido-1-phenylpropyl)-2-hydroxyiminoacetamide, a key compound for the preparation of acetylcholinesterase (AChE) reactivators of the N-substituted 2-hydroxyiminoacetamide type, it was necessary to develop a method for forming an amide bond between an ethyl glyoxylate oxime and an amine. Using Candida antarctica lipase B (CAL-B) in a cascade enzyme-BOP catalyzed reaction, the efficient synthesis of the target hydroxyiminoacetamide was achieved.     

High throughput plasma N-glycome profiling using multiplexed labelling and UPLC with fluorescence detection

A rapid glycomic profiling method is described wherein N-glycans from plasma samples individually labelled with aniline, 2-aminobenzamide and 2-aminoacridone are mixed, co-injected and separated in the same HILIC-fluorescence run. Transfer of the multiplexed method to UPLC-fluorescence permits an increase in sample throughput from 24 to 864 plasma samples per day.     

Exact solution of the impure one-dimensional n-vector model with bilinear and biquadratic exchange interactions

We demonstrate explicitly that the impure one-dimensional n-vector model with bilinear and biquadratic exchange interactions can be solved exactly. Results are provided for the free energy, equal-time spin-spin correlation functions and the initial susceptibility of the corresponding bond and site model in the annealed and quenched limit. A numerical analysis of the thermodynamic response functions in the n = 3 case is performed, and therein some interesting consequences of the simultaneous influence of the biquadratic interactions and impurities are established. The presence of the biquadratic interaction is interpreted as an effect of the lattice compressibility.