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The authors analyze modern achievements in technical diagnostics and methodology and determine their possibility to improve the quality of diagnostic support of promising and existing radio-electronic technical means. A general algorithm for the development of diagnostic support for radio-electronic devices is proposed taking into account their structure, repair conditions, and metrological support to minimize the average recovery time. [ABSTRACT FROM AUTHOR]

AIOLOS, also known as IKZF3, is a transcription factor that is highly expressed in the lymphoid lineage and is critical for lymphocyte differentiation and development. Here, we report on 9 individuals from 3 unrelated families carrying AIOLOS variants Q402* or E82K, which led to AIOLOS haploinsufficiency through different mechanisms of action. Nonsense mutant Q402* displayed abnormal DNA binding, pericentromeric targeting, posttranscriptional modification, and transcriptome regulation. Structurally, the mutant lacked the AIOLOS zinc finger (ZF) 5-6 dimerization domain, but was still able to homodimerize with WT AIOLOS and negatively regulate DNA binding through ZF1, a previously unrecognized function for this domain. Missense mutant E82K showed overall normal AIOLOS functions; however, by affecting a redefined AIOLOS protein stability domain, it also led to haploinsufficiency. Patients with AIOLOS haploinsufficiency showed hypogammaglobulinemia, recurrent infections, autoimmunity, and allergy, but with incomplete clinical penetrance. Altogether, these data redefine the AIOLOS structure-function relationship and expand the spectrum of AIOLOS-associated diseases. [ABSTRACT FROM AUTHOR]

A Lorentzian manifold, N, endowed with a time function, τ, can be converted into a metric space using the null distance, d ̂ τ , defined by Sormani and Vega [Classical Quant. Grav. 33(8), 085001 (2016)]. We show that if the time function is a regular cosmological time function as studied by Andersson, Galloway, and Howard [Classical Quant. Grav. 15(2), 309–322 (1998)], and also by Wald and Yip [J. Math. Phys. 22, 2659–2665 (1981)], or if, more generally, it satisfies the anti-Lipschitz condition of Chruściel, Grant, and Minguzzi [Ann. Henri Poincare 17(10), 2801–2824 (2016)], then the causal structure is encoded by the null distance in the following sense: for any p ∈ N, there is an open neighborhood Up such that for any q ∈ Up, we have d ̂ τ (p , q) = τ (q) − τ (p) if and only if q lies in the causal future of p. The local encoding of causality can be applied to prove the global encoding of causality in a variety of settings, including spacetimes N where τ is a proper function. As a consequence, in dimension n + 1, n ≥ 2, we prove that if there is a bijective map between two such spacetimes, F : M1 → M2, which preserves the cosmological time function, τ2(F(p)) = τ1(p) for any p ∈ M1, and preserves the null distance, d ̂ τ 2 (F (p) , F (q)) = d ̂ τ 1 (p , q) for any p, q ∈ M1, then there is a Lorentzian isometry between them, F∗g1 = g2. This yields a canonical procedure allowing us to convert large classes of spacetimes into unique metric spaces with causal structures and time functions. This will be applied in our upcoming work to define spacetime intrinsic flat convergence. [ABSTRACT FROM AUTHOR]

This article contains an exposition of a quasi-biological model of radiation carcinogenesis. The model was developed to describe the dependence of the radiogenic cancer incidence rate on the age at single exposure to radiation and the age at follow-up. The mathematical image of the model is compared with the corresponding ICRP and UNSCEAR mathematical models. The model is used to analyze the latest data on the cancer incidence rate in a cohort of Japanese people (2009) exposed to radiation from atomic explosions in 1945. It is shown to have methodological possibilities and advantages. The model parameters of radiogenic and background cancer incidence rates in the LSS cohort are given. [ABSTRACT FROM AUTHOR]

We propose a new foliation of asymptotically Euclidean initial data sets by 2-spheres of constant spacetime mean curvature (STCMC). The leaves of the foliation have the STCMC-property regardless of the initial data set in which the foliation is constructed which asserts that there is a plethora of STCMC 2-spheres in a neighborhood of spatial infinity of any asymptotically flat spacetime. The STCMC-foliation can be understood as a equivariant relativistic generalization of the CMC-foliation suggested by Huisken and Yau (Invent Math 124:281–311, 1996). We show that a unique STCMC-foliation exists near infinity of any asymptotically Euclidean initial data set with non-vanishing energy which allows for the definition of a new notion of total center of mass for isolated systems. This STCMC-center of mass transforms equivariantly under the asymptotic Poincaré group of the ambient spacetime and in particular evolves under the Einstein evolution equations like a point particle in Special Relativity. The new definition also remedies subtle deficiencies in the CMC-approach to defining the total center of mass suggested by Huisken and Yau (Invent Math 124:281–311, 1996) which were described by Cederbaum and Nerz (Ann Henri Poincaré 16:1609–1631, 2015). [ABSTRACT FROM AUTHOR]

We solve the Jang equation with respect to asymptotically hyperbolic "hyperboloidal" initial data. The results are applied to give a non-spinor proof of the positive mass theorem in the asymptotically hyperbolic setting. This work focuses on the case when the spatial dimension is equal to three. [ABSTRACT FROM AUTHOR]

The authors' point of view, as expressed in publications, on the evolution of models taking into account the irregularity of irradiation in time, which are contained in the ICRP Recommendations and are used in radiation risk assessment, is generalized. The formal nature and imperfection of these models is noted. The need to build models based on biological concepts of radiation carcinogenesis is justified. [ABSTRACT FROM AUTHOR]

The study was performed for miscanthus introduced and grown in West Siberia. Transformation of miscanthus into bacterial nanocellulose was accomplished for the first time. The microbiological synthesis of bacterial nanocellulose using the Medusomyces gisevii Sa-12 symbiotic culture gave chemically pure bacterial nanocellulose with exceptionally high crystallinity index and content of Iα allomorph. [ABSTRACT FROM AUTHOR]

The use of proteases makes it possible to obtain partially hydrolyzed forms of macromolecules with unique properties. The importance of proteases for studying the structure and functions of fibrinogen forces scientists to search for new sources of highly specific proteases. Thus, the aim of this work was to study the content of the Pleurotus ostreatus culture fluid in search of fibrinogen-specific proteases. P. ostreatus was cultured for 14 days at 27°C. The culture fluid was collected and the protein fraction was salted out with NaCl and then dialyzed. Fibrinogen hydrolysis products by P. ostreatus protease were characterized using SDS PAGE under reducing conditions followed by immunoprobing using murine monoclonal antibodies I-5A (anti-Aα505-610) and 2d2a (anti-Bβ26-42). The study of turbidity and platelet aggregation was performed using a Multiskan FC spectrophotometric microplate reader and a SOLAR-2110 aggregometer, respectively. Electron microscopy of fibrils formed by truncated compared with native fibrins was performed using a transmission electron microscope N-600. Analysis of the products of fibrinogen hydrolysis with a fungal protease using SDS-PAGE demonstrated the cleavage of the alpha chain of fibrinogen exclusively with the formation of a truncated form of fibrinogen in which there are no C-terminal portions of αC regions with a molecular weight of 25 kDa. A study of turbidity showed that the polymerization of truncated fibrin is significantly impaired. The rate of lateral association of protofibrils significantly decreased from 1.5 to 2.2 times in the case of truncated fibrinogen compared to the native one depending on the initial concentration of fibrinogen. It was shown that platelet aggregation in the presence of fibrinogen without 25 kDa fragments of αC regions was less effective than in the presence of native fibrinogen. Application of the preparation of the fungal protease allows us to obtain high molecular forms of the fibrinogen molecule with cleaved 25 kDa peptides, which provide new information on the role of these peptides in the fibrinogen functioning. [ABSTRACT FROM AUTHOR]

The vast diversity of fungal proteases and the specificity of their action have attracted attention in attempts to exploit their physiological and biotechnological applications. These enzymes are widely used in biotechnology, mainly in food, leather, and detergent industries, in ecological bioremediation processes and to produce therapeutic peptides. This review covers various aspects of aspartic proteases from basidiomycetes including sources, production, structural peculiarities, physicochemical properties and their diverse applications. [ABSTRACT FROM AUTHOR]

Cellulose nitrates corresponding in the basic properties to high-viscosity lacquer-grade colloxylin were prepared by esterification of cellulose pulp, isolated from domestic rapidly renewable feedstock—agroindustrial waste—oat hulls, or cotton cellulose with a sulfuric and nitric acid mixture. The experimental samples of cellulose nitrates were comparatively evaluated. The IR and 13С NMR spectroscopy data confirmed the identity of chemical structure. High chemical purity of samples was confirmed by differential scanning calorimetry and ampule chromatography procedure. The cellulose nitrate samples have satisfactory mechanical sensitivity level: the lower limit of impact sensitivity is 50 mm and that of friction sensitivity is 1200 kgf/cm2; they have good chemical compatibility and high chemical stability when blended with plasticizers. The obtained results attest to expediency of using cellulose nitrates from oat hulls as a component of explosive compositions. [ABSTRACT FROM AUTHOR]

The paper deals with the mathematical modeling of the controlled motion of an automatic underwater vehicle under conditions of inaccuracy and uncertainty of information support. Methodological and theoretical approaches based on the application of the principle of complexity and fuzzy logic are proposed. [ABSTRACT FROM AUTHOR]

Abstract: Samples of technical-grade cellulose isolated by nitric acid technique from unconventional feedstocks (oat hulls, Miscanthus, and intermediate flax straw) have been treated for the first time with a sulfuric acid-nitric acid mixture to give cellulose nitrates with a nitrogen content of 12.04-12.26%, viscosity 10-14 mPa s, and a solubility in an alcohol-ether mixture of at least 98%, which corresponds to industrial lacquer-purpose high-viscosity colloxylin and N-grade colloxylin. It has been confirmed by IR spectroscopy and differential scanning colorimetry that the cellulose nitrates from unconventional feedstocks correspond to industrial colloxylins in terms of the key absorption bands (1650-1635, 1279-1276, 831-825, 746, 687-672 cm-1), thermal degradation onset temperature (about 200°C), and specific heat of decomposition (6.28-7.54 kJ/g). [ABSTRACT FROM AUTHOR]

We use the notion of intrinsic flat distance to address the almost rigidity of the positive mass theorem for asymptotically hyperbolic manifolds. In particular, we prove that a sequence of spherically symmetric asymptotically hyperbolic manifolds satisfying the conditions of the positive mass theorem converges to hyperbolic space in the intrinsic flat sense, if the limit of the mass along the sequence is zero. [ABSTRACT FROM AUTHOR]

A model of a hypothetical process resulting in damage to DNA by ionizing radiation, as a result of which a nonlinear dose dependence of carcinogensis can form at dose 10-100 mGy, is examined on the basis of a microdosimetric approach. The model assumes that the primary damage to DNA interacts with short-lived products of irradiation before the DNA is repaired or transformed into a precancerous defect that is transferred to a daughter cell. It is shown that there are grounds for using the ICRP effective dose and dose rate lowering coefficient equal to 2 in the evaluation of the lifetime risk of irradiation with a significant dose and in the validation of criteria for radiation safety on the basis of data on morbidity and mortality in a cohort of Japanese atomic bomb survivors. [ABSTRACT FROM AUTHOR]

The influence of introduction of particles of detonation-synthesized nanodiamonds into composites and aluminum-base light alloys on their physical and mechanical properties is analyzed. The data on microstructure and physical and mechanical properties of composites and cast aluminum alloys reinforced with diamond nanoparticles are presented. The introduction of nanoparticles is shown to result in a significant improvement of the material properties. [ABSTRACT FROM AUTHOR]

The concept of manufacturing valuable bacterial nanocellulose (BNC) from plant raw materials having a zero prime cost is substantiated. The process flowsheet involves the chemical transformation of the feedstock to obtain a pulp; enzymatic hydrolysis of the pulp to furnish a solution of reducing sugars, chiefly glucose; preparation of a nutrient broth based on the enzymatic hydrolysate; biosynthesis of nanocellulose microfibrils by the symbiotic Medusomyces gisevii Sa-12 culture; and purification of BNC. BNC has for the first time been synthesized from oat hulls and has a high degree of crystallinity of 88 ± 5% and is composed of 99% Iα-allomorph. [ABSTRACT FROM AUTHOR]

We propose a model that describes the bacterial chemotaxis in a one-dimensional system. In this model we account the interaction of the bacterial colony with an attractant through the mechanism of its absorption by bacteria. So, the redistribution of an attractant in the system is caused by diffusion and absorption. The absorption in its turn depends on bacteria distribution which is determined by the distribution of an attractant. As a result, there is a sequence of nonlinear interactions in the system. It is important that all these processes also depend on the regime of the attractant's injection into the system. The regime is modulated by means of boundary conditions. Namely, we consider the situation when the ratio of the attractant's concentrations at the boundaries is fixed, when the flow of attractant through the boundary is absent, and when the difference of attractant concentrations at the boundaries is constant. In all these cases we investigate the chemotaxis sensitivity function which characterizes inhomogeneity of bacterial distribution in the system. To do that we solve numerically nonlinear differential equation and find both the distribution of an attractant and bacteria. Basing on these distributions we calculate the chemotaxis sensitivity function. In particular, we study how it depends on the concentration of an attractant at the boundary of the system. It is shown that depending on the boundary regime this function may have one or two peaks. The first peak is caused by the process of the bacteria receptors' saturation. The second peak may appear due to the saturation of absorption intensity. We also analyze a certain dependence of the chemotaxis sensitivity function on the parameters of the model. The results that have been received could be useful for understanding experimental data on chemotaxis in different systems. [ABSTRACT FROM AUTHOR]

Highlights: [•] Internal conversion to ground state is a path to lower quantum yield in polar media. [•] The probe's hydration enhances non-radiative relaxation of the lowest excited singlet. [•] The mobility of the polyene chain is a key factor in non-radiative relaxation process. [ABSTRACT FROM AUTHOR]

Objectives Our purpose was to identify the incidence and significance of markers of systemic connective tissue abnormalities ( CTA) in patients with saccular intracranial aneurysms ( SIA). Materials and methods This prospective case-control study included 199 consecutive patients with SIA (103 women and 96 men, mean age - 43.2 years) and 194 control patients - blood donors (108 - men, 86 - women, mean age - 38.4 years). Aneurysms were verified by conventional cerebral angiography. All patients were examined by the first author using a specially designed questionnaire and a standardized physical examination with special emphasis on systemic CTA. Results Twelve markers of systemic CTA were significantly higher in patients with SIA than in controls: visible vessels on face and chest (59.8%), scoliosis (44.7%), varicose veins in legs (39.7%), flatfoot (34.6%), hyperextensibility of the skin (33.6%), spontaneous epistaxis (25.6%), easy bruising (20.6%), abdominal hernia (13.6%), periodontal disease (10.5%), chest deformations (7.5%), abdominal striae (3.5%), joint hypermobility (2.5%). A blinded validation study in a subset of 43 patients showed similar results. Among patients with SIA, 125 of 199 patients (62.8%) had at least three markers of systemic CTA compared with 23 (11.8%) of the controls (P < 0.0001, OR = 12.5, 95% CI 7.45-21.1). The mean number of markers of systemic CTA in patients with SIA was 3.07 and 1.17 in controls. Conclusion Patients with SIA have multiple markers of systemic connective tissue abnormalities. Systemic weakness of connective tissue represents a risk factor for development of SIA. Identification of these markers may help in detection of high-risk patients. [ABSTRACT FROM AUTHOR]

The quantum chemical simulation of the ground and electron-excited states of diverse complexes of fluorescent probe 4-dimethylaminochalcone (DMAC) and water in vacuo was performed by the HF/MP2 and RI-CC2 methods. Molecules of the DMAC probe and water can form five types of stable complexes. The geometries corresponding to the potential energy minimum and dipole moments for two lowest singlet and one lowest triplet states were calculated for each type of the complexes. The partial charges on the DMAC atoms and their changes due to the intramolecular charge transfer upon photoexcitation were determined. The coordination of the water molecule at the carbonyl group of DMAC is preferable in vacuo. The formation of hydrogen bonds between the carbonyl group of DMAC and water molecules decreases the energy of the excited state of the complex (π, π*), due to which the fluorescence yield increases upon photoexcitation. The calculation results are confirmed by the experimental data on studying the fluorescence of the probe in binary mixtures of benzene and alcohols. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Partial leukocyte adhesion deficiency type 1 (LAD‐1) deficiency is extremely rare condition with milder infectious manifestation and immune system imbalance leads to increased risks of autoinflammatory complications, such as pyoderma gangrenosum, that can be triggered by trauma or pregnancy. In patients with spice‐site ITGB2 variants, partial expression can occur due to different β2 integrin isophorms expression. LAD‐1, OMIM ID #116920 is a rare, autosomal recessive disorder that results from mutations in the ITGB2 gene that encodes the CD18 β2 integrin subunit. According to the CD18 expression, LAD‐1 is categorized as severe (<2%), moderate (2%–30%), or mild (>30%). Here, we describe a 22‐year‐old female, who presented with inflammatory skin disease and oral cavity, as well as respiratory tract infections during the first year of life. LAD‐1 was diagnosed at the age of 2 years by low expression of CD18 (1%). Whole‐exome sequencing identified homozygous c. 59‐10C>A variant in the ITGB2 gene. Despite severe phenotype, the patient survived to adulthood without hematopoietic stem cell transplantation and became pregnant at the age of 20 years, with pregnancy complicated by a pyoderma gangrenosum‐like lesion. During her life, CD18 expression increased from 1% to 9%; at 22 years of age, 5% of neutrophils and 9% of lymphocytes were CD18+. All CD18+‐lymphocytes were predominantly memory/effector cytotoxic T cells. However, revertant mosaicism was not being established suggesting that CD18 expression variability may be mediated by other mechanisms such as different β2 integrin isophorms expression. [ABSTRACT FROM AUTHOR]

Alkylation of 4(5)-nitro-1,2,3-triazole with alcohols in concentrated H 2SO 4 occurs at all three endocyclic N atoms, giving a mixture of isomeric N(1)-, N(2)-, and N(3)-alkyl-4-nitro-1,2,3-triazoles (alkyl is isopropyl, sec-butyl, and cyclohexyl). The selectivity of the alkylation depends on the alcohol used. The most selective alkylation is provided at the N(2) atom when isopropyl (81%) and sec-butyl alcohols are used (67%). With an increase in the reaction time, also in the order isopropyl-, sec-butyl-, and cyclohexyl-4-nitro-1,2,3-triazoles, the N(2)-isomers undergo isomerization into N(1)-alkyl-4-nitro-1,2,3-triazoles. In all the cases, the fraction of the N(3)-substitution products in the mixtures is 6–30%. [ABSTRACT FROM AUTHOR]

We prove a general criterion of spectral stability of multi-site breathers in the discrete Klein-Gordon equation with a small coupling constant. In the anticontinuum limit, multi-site breathers represent excited oscillations at different sites of the lattice separated by a number of 'holes' (sites at rest). The criterion describes how the stability or instability of a multi-site breather depends on the phase difference and distance between the excited oscillators. Previously, only multi-site breathers with adjacent excited sites were considered within the first-order perturbation theory. We showthat the stability of multi-site breathers with one-site holes changes for large-amplitude oscillations in soft nonlinear potentials. We also discover and study a symmetry-breaking (pitchfork) bifurcation of one-site and multi-site breathers in soft quartic potentials near the points of 1 : 3 resonance. [ABSTRACT FROM AUTHOR]

We construct solutions of the constraint equation with non constant mean curvature on an asymptotically hyperbolic manifold by the conformal method. Our approach consists in decreasing a certain exponent appearing in the equations, constructing solutions of these sub-critical equations and then in letting the exponent tend to its true value. We prove that the solutions of the sub-critical equations remain bounded which yields solutions of the constraint equation unless a certain limit equation admits a non-trivial solution. Finally, we give conditions which ensure that the limit equation admits no non-trivial solution. [ABSTRACT FROM AUTHOR]

The interaction of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with bifunctional agents - β,β′-dichloro- and β,β′-(dinitroxy)diethyl ethers - in the presence of alkali proceeds with the formation of a mixture of products substituted at the N(1) and N(2) atoms of the heterocycle, consisting of three reaction products, the N(1),N′(1)-, N(1),N′(2)-, and N(2),N′(2) isomeric derivatives of nitrotriazoles. Replacement of the Cl leaving group in the alkylating agent by a NO group does not lead to a substantial change in the degree of conversion and overall yield of alkylation products. The ratio of N(1),N′(1):N(1),N′(2):N(2),N′(2) isomeric reaction products from 3-nitro-1,2,4-triazole was (82.0-85.7): (7.7-9.9):(6.6-8.1), and from 5-methyl-3-nitro-1,2,4-triazole was (76.9-79.8):(10.1:11.4):(10.1-11.7) respectively. [ABSTRACT FROM AUTHOR]

We find a transformation which relates a new third-order integrable nonlinear evolution equation, introduced recently by Qiao, with the well-known modified Korteweg-de Vries equation. Then we use this transformation to derive smooth soliton solutions of the new equation from the known rational and soliton solutions of the old one. [ABSTRACT FROM AUTHOR]

Abstract: Discrete solitons of the discrete nonlinear Schrödinger (dNLS) equation are compactly supported in the anti-continuum limit of the zero coupling between lattice sites. Eigenvalues of the linearization of the dNLS equation at the discrete soliton determine its spectral stability. Small eigenvalues bifurcating from the zero eigenvalue near the anti-continuum limit were characterized earlier for this model. Here we analyze the resolvent operator and prove that it is bounded in the neighborhood of the continuous spectrum if the discrete soliton is simply connected in the anti-continuum limit. This result rules out the existence of internal modes (neutrally stable eigenvalues of the discrete spectrum) near the anti-continuum limit. [ABSTRACT FROM AUTHOR]

For the Bakirov system, which is known to possess only one higher-order local generalized symmetry, we explicitly find a zero-curvature representation containing an essential parameter. [ABSTRACT FROM AUTHOR]

The N-monoalkylation of 3-nitro, 5-methyl-3-nitro, and 5-ethyl-3-nitro-1,2,4-triazoles by epichlorohydrin polymers and copolymers is nonselective in the presence of base. The reaction products are nitrotriazoles substituted by the polymeric chain in positions 1 or 2 of the heterocycle. The mass fraction of the 2-isomer is 9.6-11.3%. The degree of substitution of the chlorine by the nitrotriazole ring is 98.0-99.5%. [ABSTRACT FROM AUTHOR]

We prove global well-posedness of the short-pulse equation with small initial data in Sobolev space H2. Our analysis relies on local well-posedness results of Schafer and Wayne [15], the correspondence of the short-pulse equation to the sine-Gordon equation in characteristic coordinates, and a number of conserved quantities of the short-pulse equation. We also prove local and global well-posedness of the sine-Gordon equation in an appropriate function space. [ABSTRACT FROM AUTHOR]

Abstract: We construct the first known complex-valued harmonic morphisms from the non-compact Lie groups , and equipped with their standard Riemannian metrics. We then introduce the notion of a bi-eigenfamily and employ this to construct the first known solutions on the non-compact Riemannian , , and . Applying a duality principle we then show how to manufacture the first known complex-valued harmonic morphisms from the compact Lie groups , and equipped with semi-Riemannian metrics. [Copyright &y& Elsevier]

Reaction of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with secondary and tertiary alcohols in conc. H2SO4 takes place at the N(2) atom. Alkylation by 2-propanol occurs regioselectively to form the 1-isopropyl-3-nitro-and 1-isopropyl-3-methyl-5-nitro-1,2,4-triazoles. As a consequence of isomerization the alkylation using cyclohexyl or tert-butyl alcohols gives respectively a mixture of regioisomers substituted at atom N(1) (1-cyclohexyl-3-nitro-and 1-cyclohexyl-5-methyl-3-nitro-1,2,4-triazoles) and at atom N(2) (5-nitro-1-cyclohexyl-and 1-cyclohexyl-3-methyl-5-nitro-1,2,4-triazoles) and, in the second case, to 1-tert-butyl-3-nitro-1,2,4-triazole. [ABSTRACT FROM AUTHOR]

Abstract: The method of obtaining new integrable coupled equations through enlarging spectral problems of known integrable equations, which was recently proposed by W.X. Ma, can produce nonintegrable systems as well. This phenomenon is demonstrated and explained by the example of the enlarged spectral problem of the Korteweg–de Vries equation. [Copyright &y& Elsevier]

The reaction of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with dimethyl sulfate leads to mixtures of N-mono- and N,N-dimethylnitrotriazolium compounds and products of the subsequent conversion of the latter, namely, N,N-dimethyl-1,2,4-triazol-5-ones. [ABSTRACT FROM AUTHOR]

Two generalized Harry Dym equations, recently found by Brunelli, Das, and Popowicz in the bosonic limit of new supersymmetric extensions of the Harry Dym hierarchy [J. Math. Phys. 44, 4756 (2003)], are transformed into previously known integrable systems: one, into a pair of decoupled KdV equations, the other one, into a pair of coupled mKdV equations from a bi-Hamiltonian hierarchy of Kupershmidt. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We study one third-order nonlinear evolution equation, recently introduced by Chou and Qu in a problem of plane curve motions, and find its transformation to the modified Korteweg–de Vries equation, its zero-curvature representation with an essential parameter, and its second-order recursion operator. [Copyright &y& Elsevier]

The integrability of a coupled KdV-mKdV system is tested by means of singularity analysis. The true Lax pair associated with this system is obtained by the use of prolongation technique. [ABSTRACT FROM AUTHOR]

Vocational guidance of secondary school students is currently at the center of attention. Many schools have set up vocational guidance corners featuring displays that tell about careers and jobs in chemistry, chemical enterprises and new industrial construction projects, at educational institutions specializing in chemistry, etc. [ABSTRACT FROM AUTHOR]

Quaternization of N -alkyl-4-nitro-1,2,3-triazoles in Bu t OH–HClO 4 as a source of tert -butyl cation affords 1- tert -butyl-3-alkyl-4-nitro- 1,2,3-triazolium perchlorates. [ABSTRACT FROM AUTHOR]

The aim of this work was to identify and to study physical and chemical properties of the enzyme preparation which was obtained from the cultural liquid of Pleurotus ostreatus. The protease containing fraction was obtained from the cultural liquid by sodium chloride precipitation followed by dialysis and concentration procedures. Gelatinase and milk-clotting activity were defined by standard methods. The content of the protein component of the fraction was analysed by HPLC, Laemmli electrophoresis and MALDI-TOF analysis. Protease activity was proved by enzyme-electrophoresis. To identify the protease, mass-spectrometry was carried out using the MatrixScience database. To study the specificity of protease action, the series of chromogenic substrates were used: S2238, S236, S2251, S2765, Leu-pNa, Ala-pNa and S2302. The inhibitory analysis was carried out using EDTA, benzamidine, PMSF, PCMB. The obtained fraction possessed maximal protease activity at 45 °C. Meanwhile maximal milk-clotting activity was observed at 35 °C. The highest milk-clotting activity was shown at pH 5.0 and less than 3.0. The highest protease activity was shown at pH 6.0. Using HPLC method, it was found the main protein component and some minor proteins. According to the electrophoresis results, the main protein component of the fraction had molecular mass 45 kDa. Enzyme electrophoresis demonstrated that protease activity of the fraction was present in the zone corresponding to 45 kDa. When identifying trypsinolysis products, no homology was found with other known proteinases. It was shown that the protease hydrolyzed peptide bonds which were formed by carboxyl group of amino acids with hydrophobic side chains. The enzyme was inhibited by EDTA (ІС50 = 2.5 mМ). The maximal enzyme activity towards gelatin and Leu-pNa was shown in the presence of 5 mM calcium chloride. The new calcium-dependent metalloprotease with molecular weight 45 kDa was found in the cultural liquid of Pleurotus ostreatus. The enzyme had no homology with other known proteases and hydrolyzes peptide bonds formed by carboxyl groups of amino acids with hydrophobic side chains. [ABSTRACT FROM AUTHOR]

Abstract: We show how the Yao–Zeng system of coupled short-pulse equations is related to the original short-pulse equation and obtain the correct zero-curvature representation of the Yao–Zeng system via this relationship. [Copyright &y& Elsevier]

We present a theoretical proposal for an integrated four-wave mixing source of narrow-band path-entangled photon pairs with efficient spatial pump self-rejection. The scheme is based on correlated loss in a system of waveguides in Kerr nonlinear media. We calculate that this setup gives the possibility for upwards of 100 dB pump rejection, without additional filtering. The effect is reached by driving the symmetric collective mode that is strongly attenuated by an engineered dissipation, while photon pairs are born in the antisymmetric mode. A similar set-up can additionally be realized for the generation of two-photon NOON states, also with pump self-rejection. We discuss the implementation of the scheme by means of the coherent diffusive photonics, and demostrate its feasibility in both glass (such as fused silica-glass and IG2) and planar semiconductor waveguide structures in indium phosphide (InP) and in silicon. [ABSTRACT FROM AUTHOR]

A method is proposed for determining the chemical composition of medcial glass by atom emission spectroscopy with arc excitation. The preparation of samples for measurement does not require acids and alkalis and consists of grinding a glass sample and subsequent dilution in the corresponding buffer solution. The metrological measurement parameters enabled analysis in the prescribed concentration ranges of the main glass elements according to GOST 19808-86. [ABSTRACT FROM AUTHOR]

The new generalized Harry Dym equation, recently introduced by Z. Popowicz in [Phys. Lett. A 317 (2003) 260], is transformed into the Hirota–Satsuma system of coupled KdV equations. [Copyright &y& Elsevier]

Both annual (cotton, flax, hemp, etc.) and perennial (trees and grasses) plants can serve as a source of cellulose for fiber production. In recent years, the perennial herbaceous plant miscanthus has attracted particular interest as a popular industrial plant with enormous potential. This industrial crop, which contains up to 57% cellulose, serves as a raw material in the chemical and biotechnology sectors. This study proposes for the first time the utilization of miscanthus, namely Miscanthus Giganteus "KAMIS", to generate spinning solutions in N-methylmorpholine-N-oxide. Miscanthus cellulose's properties were identified using standard methods for determining the constituent composition, including also IR and atomic emission spectroscopy. The dry-jet wet method was used to make fibers from cellulose solutions with an appropriate viscosity/elasticity ratio. The structural characteristics of the fibers were studied using IR and scanning electron microscopy, as well as via X-ray structural analysis. The mechanical and thermal properties of the novel type of hydrated cellulose fibers demonstrated the possibility of producing high-quality fibers from miscanthus. [ABSTRACT FROM AUTHOR]