Разностные характеристики по модулю 2n композиции нескольких побитовых исключающих или

We study the additive differential probabilities adp® of compositions of k — 1 bitwise XORs. For vectors a1,...,ak+1 G Zn, it is defined as the probability of transformation input differences a1,...,ak to the output difference ak+1 by the function x1 ф ... ф xk, where x1,... ,xk G Zn and k > 2. It is used for differential cryptanalysis of symmetric-key primitives, such as Addition-Rotation-XOR constructions. Several results which are known for adp2® are generalized for adpk®. Some argument symmetries are proven for adpk®. Recurrence formulas which allow us to reduce the dimension of the arguments are obtained. All impossible differentials as well as all differentials of adpk® with the probability 1 are found. For even k, it is proven that max adp® (a1,..., ak ak+1) = adp®(0,..., 0, ak+1 ak+1). Matrices that can a1,...,ak be used for efficient calculating adpk® are constructed. It is also shown that the cases of even and odd k differ significantly

Geometric phase and o-mode blue shift in a chiral anisotropic medium inside a Fabry-P\'erot cavity

Anomalous spectral shift of transmission peaks is observed in a Fabry--P\'erot cavity filled with a chiral anisotropic medium. The effective refractive index value resides out of the interval between the ordinary and the extraordinary refractive indices. The spectral shift is explained by contribution of a geometric phase. The problem is solved analytically using the approximate Jones matrix method, numerically using the accurate Berreman method and geometrically using the generalized Mauguin--Poincar\'e rolling cone method. The $o$-mode blue shift is measured for a 4-methoxybenzylidene-4'-$n$-butylaniline twisted--nematic layer inside the Fabry--P\'erot cavity. The twist is electrically induced due to the homeoplanar--twisted configuration transition in an ionic-surfactant-doped liquid crystal layer. Experimental evidence confirms the validity of the theoretical model.Comment: the text is available both in English (Timofeev2015en.tex) and in Russian (download: other formats - source - Timofeev2015ru.tex, Timofeev2015rus.pdf

Set of enzymatic bioassays for assessment of soil contamination

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.A concept of the comprehensive assessment of soil contamination is proposed. According to it, the conclusion regarding the presence of toxic substances in the analyzed sample is based on the inhibition of enzymatic reactions responsible for various functions of a living organism, such as luminescence, respiration, etc. These functions are taken as test functions in classical bioassays with the use of living objects (luminous bacteria, daphnia, algae, and others). The regularities of the impact of different classes of toxicants on the activity of particular enzymes or coupled oligo-enzyme chains have been established. These enzyme reactions are selected as potential test objects: markers of contamination. Three enzyme systems with the maximal sensitivity to different classes of toxicants have been chosen for the set of enzymatic bioassays: butyrylcholinesterase, NAD(P)H:FMN-oxidoreductase + luciferase, and lactate dehydrogenase + NAD(P)H:FMN-oxidoreductase + luciferase. The possibility to use enzymes instead of living organisms in the bioassay of natural complex systems has been shown

Photonic bound states in the continuum governed by heating

A photonic crystal microcavity with the liquid crystal resonant layer tunable by heating has been implemented. The multiple vanishing resonant lines corresponding to optical bound states in the continuum are observed. The abrupt behaviour of the resonant linewidth near the vanishing point can be used for temperature sensing

An anomaly in inclusive pion double charge exchange on 16O at about 1GeV

The new results on the inclusive double charge exchange (DCX) reaction 16O(π-,π+)X at incident kinetic energy T0=0.75 and 1.15GeV are presented. The data were taken without using Cherentov counters. The new DCX cross sections agree well with the old ones. Both the values are about an order of magnitude larger than the theoretical cross sections calculated for the standard sequential mechanism. Two other approaches wich seem to explain the discrepancy are also briefly reviewed.Vicente Vacas, Manuel Jose, [email protected]

Toxicity of Different Types of Surfactants via Cellular and Enzymatic Assay Systems

Surfactants have a widespread occurrence, not only as household detergents, but also in their application in industry and medicine. There are numerous bioassays for assessing surfactant toxicity, but investigations of their impact on biological systems at the molecular level are still needed. In this paper, luminous marine bacteria and their coupled NAD(P)H:FMN-oxidoreductase + luciferase (Red + Luc) enzyme system was applied to examine the effects of different types of surfactants, including cationic cetyltrimethylammonium bromide (CTAB), non-ionic polyoxyethylene 20 sorbitan monooleate (Tween 80) and anionic sodium lauryl sulfate (SLS), and to assess whether the Red + Luc enzyme system can be used as a more sensitive indicator of toxicity. It was shown that the greatest inhibitory effect of the surfactants on the activity of luminous bacteria and the Red + Luc enzyme system was in the presence of SLS samples. The calculated IC50 and EC50 values of SLS were 10−5 M and 10−2 M for the enzymatic and cellular assay systems, respectively. The results highlight the benefits of using the enzymatic assay system in ecotoxicology as a tool for revealing surfactant effects on intracellular proteins if the cellular membrane is damaged under a long-term exposure period in the presence of the surfactants. For this purpose, the bioluminescent enzyme-inhibition-based assay could be used as an advanced research tool for the evaluation of surfactant toxicity at the molecular level of living organisms due to its technical simplicity and rapid response time

Geometric phase and o-mode blueshift in a chiral anisotropic medium inside a Fabry-P´erot cavity

Anomalous spectral shift of transmission peaks is observed in a Fabry-P´erot cavity filled with a chiral anisotropic medium. The effective refractive index value resides out of the interval between the ordinary and the extraordinary refractive indices. The spectral shift is explained by contribution of a geometric phase. The problem is solved analytically using the approximate Jones matrix method, numerically using the accurate Berreman method, and geometrically using the generalized Mauguin-Poincar´e rolling cone method. The o-mode blueshift is measured for a 4-methoxybenzylidene-4 -n-butylaniline twisted-nematic layer inside the Fabry-P´erot cavity. The twist is electrically induced due to the homeoplanar-twisted configuration transition in an ionic-surfactant-doped liquid crystal layer. Experimental evidence confirms the validity of the theoretical model