Tripodal oxazolidine-N-oxyl diradical complexes of Dy3+ and Eu3+

Two diradical complexes of the formula [LnRad2(CF3SO3)3] c (Ln(III) = Dy, Eu, Rad = 4,4-dimethyl-2,2-bis(pyridin-2-yl)-1,3-oxazolidine-3-oxyl) were obtained in air conditions. These are the first examples of diradical compounds of lanthanides and oxazolidine nitroxide. The complexes were characterized crystallographically and magnetically. Single crystal XRD analysis revealed that their coordination sphere is composed of three monodentate triflates and two tripodal Rad, which coordinate the central atom in a tridentate manner via two N atoms of the pyridine groups and the O atom of a nitroxide group. The LnO5N4 polyhedron represents a spherical capped square antiprism with point symmetry close to C4v. The data of static magnetic measurements are compatible with the presence of two paramagnetic ligands in the coordination sphere of the metal

Prospects for the development of electronic commerce in Russia in the conditions of digital economy

E-commerce is a form of running business using information and communication technologies. E-commerce objects include not only traditional types of services and goods, but also informational ones. In general, the trends in e-commerce development in Russia can be regarded as positive. The ongoing coronavirus pandemic affects everything, including spending money and interaction of firms in the marketplace. Current trends indicate an acceleration in digitalization, both in the private and public sectors. Therefore, in the future, only the online seller will have success whose business will be digitized and optimized as much as possible. At the same time, the transition of firms and consumers to the electronic segment is associated with certain costs and risks. This aspect requires serious attention from both academic economists and authorities; competent, but not excessive, intervention is required. In this article, the authors reveal both the positive and negative aspects of running e-business from the point of view of sellers and buyers, and also offer their own views on the e-commerce market development in the context of mass digitalization accelerated due to the coronavirus crisis. Provided that the rate of Internet penetration in the regions remains at the same level, e-commerce in Russia will be able to maintain the current growth rate and realize its potential as an important trading platform for both domestic and foreign economic agents

Effect of organically bound iodine in cattle feed on health indicators

Currently, the problem of iodine deficiency is actual in the world, which may cause a large number of diseases and disorders. The problem of iodine deficiency for humans may be partly solved by enriching agricultural products with iodine, i.e. by providing animals with an increased intake of iodine during their growth. Theoretically, the most effective way to use iodine is the form bound to tyrosine, since diiodotyrosine has been proven to be a thyroxine precursor. Taking it into account, a supplement was developed containing iodine organically bound to tyrosine and histidine. In this work, we studied the effect of this supplement introduced into the diets of cattle on biochemical parameters of animal blood. In the test group, which received the supplement with organically bound iodine, an improvement in nitrogen metabolism was noted compared to the control group. This was most clearly demonstrated by the content of urea, since in the test group, its content decreased by ≈15 percentage points, and by the content of creatinine, since its increase in the test group was more than 20 percentage points. Differences in the parameters of carbohydrate and lipid metabolism between treatments were also noted, as in the blood of animals from the test group, the content of cholesterol, triglycerides, phospholipids, glucose and malondialdehyde was lower than in the control group. In mineral metabolism and morphological parameters, there was no significant difference between treatments. Among the indicators of pigment and hormone metabolism, it is important to note the reduced content of cortisol in the blood of animals from the test group. Its level was lower by ≈17.23 percentage points compared to the control group. A decrease in cortisol levels indicated a lower stress load in the test group. In general, studies have shown that the use of a feed supplement containing organically bound iodine has a positive effect on the metabolism of animals.Currently, the problem of iodine deficiency is actual in the world, which may cause a large number of diseases and disorders. The problem of iodine deficiency for humans may be partly solved by enriching agricultural products with iodine, i.e. by providing animals with an increased intake of iodine during their growth. Theoretically, the most effective way to use iodine is the form bound to tyrosine, since diiodotyrosine has been proven to be a thyroxine precursor. Taking it into account, a supplement was developed containing iodine organically bound to tyrosine and histidine. In this work, we studied the effect of this supplement introduced into the diets of cattle on biochemical parameters of animal blood. In the test group, which received the supplement with organically bound iodine, an improvement in nitrogen metabolism was noted compared to the control group. This was most clearly demonstrated by the content of urea, since in the test group, its content decreased by ≈15 percentage points, and by the content of creatinine, since its increase in the test group was more than 20 percentage points. Differences in the parameters of carbohydrate and lipid metabolism between treatments were also noted, as in the blood of animals from the test group, the content of cholesterol, triglycerides, phospholipids, glucose and malondialdehyde was lower than in the control group. In mineral metabolism and morphological parameters, there was no significant difference between treatments. Among the indicators of pigment and hormone metabolism, it is important to note the reduced content of cortisol in the blood of animals from the test group. Its level was lower by ≈17.23 percentage points compared to the control group. A decrease in cortisol levels indicated a lower stress load in the test group. In general, studies have shown that the use of a feed supplement containing organically bound iodine has a positive effect on the metabolism of animals

Electrical excitation of shock and soliton-like waves in two-dimensional electron channels

We study electrical excitation of nonlinear plasma waves in heterostructures with two-dimensional electron channels and with split gates, and the propagation of these waves using hydrodynamic equations for electron transport coupled with two-dimensional Poisson equation for self-consistent electric potential. The term related to electron collisions with impurities and phonons as well as the term associated with viscosity are included into the hydrodynamic equations. We demonstrate the formation of shock and soliton-like waves as a result of the evolution of strongly nonuniform initial electron density distribution. It is shown that the shock wave front and the shape of soliton-like pulses pronouncedly depend on the coefficient of viscosity, the thickness of the gate layer and the nonuniformity of the donor distribution along the channel. The electron collisions result in damping of the shock and soliton-like waves, while they do not markedly affect the thickness of the shock wave front.Comment: 9 pages, 11 figure

Molecular genetic methods for identifying raw materials in meat products: Diversity, opportunities and prospects

In the current economic situation, after easing the Covid pandemic restrictions, almost all laboratories, which are focused on evaluation of the conformity of food products, have faced issues in supplying for their laboratories. In this regard, in the last years many laboratories have been forced to validate new approaches and introduce new methods for assessing conformity of the food products. Very often it is not possible to use only one method to resolve the issue of the food product ingredients, especially for the purpose of traceability of their names and the used raw materials, listed on the label. Survey of the raw food materials to determine whether they correspond to the type name is a simpler task, in contrast to survey of the multicomponent food product. Many researchers have to estimate the opportunities and feasibility of application of various methodologies in their workplaces. Therefore, this review is relevant for the researchers in this field, as it focuses on aspects and special features of similar methodologies. The prospect of molecular genetic methods for identification of the raw materials used for manufacturing of meat products is presented below. This review also represents characteristics of methods for identification of the sources of raw materials used for the manufacturing of the meat products, based on the recognition of species-specific sections within the nucleic acids structures. The variety of methods (hybridization methods, polymerase chain reaction, different types of isothermal amplifications, methods using CRISPR/Cas systems), the principles of their implementation, and achieved analytical characteristics are considered. The capacities and competitive potential of various methods are discussed, as well as approaches being developed to overcome the existing limitations.In the current economic situation, after easing the Covid pandemic restrictions, almost all laboratories, which are focused on evaluation of the conformity of food products, have faced issues in supplying for their laboratories. In this regard, in the last years many laboratories have been forced to validate new approaches and introduce new methods for assessing conformity of the food products. Very often it is not possible to use only one method to resolve the issue of the food product ingredients, especially for the purpose of traceability of their names and the used raw materials, listed on the label. Survey of the raw food materials to determine whether they correspond to the type name is a simpler task, in contrast to survey of the multicomponent food product. Many researchers have to estimate the opportunities and feasibility of application of various methodologies in their workplaces. Therefore, this review is relevant for the researchers in this field, as it focuses on aspects and special features of similar methodologies. The prospect of molecular genetic methods for identification of the raw materials used for manufacturing of meat products is presented below. This review also represents characteristics of methods for identification of the sources of raw materials used for the manufacturing of the meat products, based on the recognition of species-specific sections within the nucleic acids structures. The variety of methods (hybridization methods, polymerase chain reaction, different types of isothermal amplifications, methods using CRISPR/Cas systems), the principles of their implementation, and achieved analytical characteristics are considered. The capacities and competitive potential of various methods are discussed, as well as approaches being developed to overcome the existing limitations

The formation of flavoring characteristics of meat products by changing the chemical composition of food compositions

The article presents the results of the study of changes in flavour characteristics when using corrective additives. Monosodium glutamate, ribotide, yeast extract and hydrolysate of vegetable soy protein were used as flavoring additives (FA). To assess the effect of composition of meat product recipe, as well as the method of FA‑introduction on taste intensity, the recipes of model meat systems with partial replacement of meat raw materials were used. Pork fat, soy protein and potato starch were used as meat substitutes. The effect of recipe composition on the content of non-volatile substances of aroma was accessed. It is shown that replacement of pork by pork fat in the recipe by 20–40% led to a sharp decrease in the concentration of aromatic substances and a decrease in intensity of taste of the finished product several times. The ways for taste correction using FA was studied. For this, a chopped semi-finished product — minced meat was prepared from chilled whole-muscle pork and 0.05% of each FA was added. It is shown that the dynamics of changes in the content of free amino acids is the most pronounced when using monosodium glutamate not as a mono-additive, but in compositions: monosodium glutamate with yeast extract and monosodium glutamate with ribotide. A pool of chemical compounds involved in the formation of taste and aroma of products was detected. The main components were derivatives of C6–C24 fatty acids, as well as a significant number of other biochemical compounds, mainly substituted amines, amides, alcohols and ketones, with a content ranging from 0.001 to 0.2 mg/kg. The results of organoleptic analysis showed that the most delicious and attractive samples were those containing monosodium glutamate with yeast extract and monosodium glutamate with ribotide

ИДЕНТИФИКАЦИЯ И КОЛИЧЕСТВЕННОЕ ОПРЕДЕЛЕНИЕ МЫШЕЧНОЙ ТКАНИ НА ОСНОВЕ КОНТРОЛЯ ПРОТОТИПИЧЕСКИХ ПЕПТИДОВ С ИСПОЛЬЗОВАНИЕМ МЕТОДА МОНИТОРИНГА ЗАДАННЫХ РЕАКЦИЙ

One of the main problems of modern production of meat products is the quality of raw meat, which depends on various factors including genetic components, conditions of transportation, production and processing. The most important components of meat are proteins, the total content, structure and functional state of which in this complex biological system with many interacting components is constantly changing. In order to study the interspecific and intraspecific features of meat proteins, their transformations in the process of maturation and processing requires modern analytical technologies based on the systematic approach to the analysis. Proteomics, as a methodology for studying proteins in a certain system and at a certain time, opens wide opportunities in this direction, allowing to identify and develop accurate analytical methods for searching biomarkers and identifying unfair practices. Given the high added value and multicomponent composition, finished meat products are among the most susceptible to adulteration. Current paper presents a technique of high-performance liquid chromatography with mass spectrometric detector (HPLC-MS) adapted for the detection and quantification of two different types of meat (beef and pork) in a complex biological matrix such as structureless minced meat. After the protein isolation and trypsin cleavage, species-specific peptide markers were selected for each animal species for the quantification. The technique was tested on model samples of a mixture of muscle tissue of the two species of animals. A good sensitivity was established with the possibility of quantitative determination of muscle tissue of each animal species using special calibration graphs. The developed technique can find wide application at the supervising organizations aimed at counteracting the discrepancies in the hidden replacement of types of meat by cheaper or low-grade raw materials.Keywords: Biomarker, prototypical peptides, HPLC-MS, species identification(Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.012D.V. Khvostov1, N.L. Vostrikova1, A.V. Zherdev2, E.A. Zvereva2, A.A. Kurzova1  1V.M. Gorbatov Federal Research Center for Food Systems of Russian Academy of Sciences, 109316 Moscow, Russian Federation 2Federal State Institution «Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences», Leninsky prospect, 33, build. 2, 119071 Moscow, Russian FederationОдной из основных проблем современного производства мясных продуктов является качество мясного сырья, которое зависит от разных факторов, включая генетические составляющие, условия транспортирования, производства и переработки. К наиболее значимым компонентам мяса относятся белки, общее содержание, структура и функциональное состояние которых в составе этой сложной биологической системы, с большим количеством взаимодействующих составляющих, постоянно изменяется. Для изучения межвидовых и внутривидовых особенностей белков мяса, трансформации их в процессе созревания и технологической обработки требуются современные аналитические технологии, основанные на системном подходе к анализу. Широкие возможности в этом направлении открывает протеомика, как методологии изучения белков в определенной системе и в определенное время, позволяющая идентифицировать и разрабатывать точные аналитические методы поиска биомаркеров и выявления недобросовестных практик. Учитывая высокую добавленную стоимость и многокомпонентность состава, готовые мясные продукты относятся к числу наиболее подверженных фальсификации. В работе представлена методика высокоэффективной жидкостной хроматографии с масс-спектрометрическим детектором (ВЭЖХ-МС), адаптированная для обнаружения и количественного определения двух различных видов мяса (говядина и свинина) в сложной биологической матрице, такой как бесструктурные фарши. После выделения белков и расщепления их трипсином были выбраны видоспецифичные пептидные маркеры для каждого вида животного с целью количественного определения. Методика была апробирована на модельных образцах смеси мышечной ткани двух видов животных. Установлена хорошая чувствительность с возможностью количественного определения мышечной ткани каждого вида животного, при использовании специальных градуировочных графиков. Разработанная методика может найти широкое применение у контролирующих организаций, направленных на противодействие несоответствиям по скрытой замене видов мяса более дешевым или низкосортными сырьем.Ключевые слова: Биомаркер, прототипические пептиды, ВЭЖХ-МС, видовая идентификацияDOI: http://dx.doi.org/10.15826/analitika.2019.23.4.01

Gender-Specific Renal Function and Urinary Syndrome in Patients with Liver Cirrhosis of Alcoholic Etiology: Observational Study

Background. Gender has now been proven to have a significant impact on the development, course and outcome of a large number of diseases, including alcoholic liver disease. Alcohol consumption is one of the leading risk factors for various diseases. Alcohol-related diseases cause 10% of all deaths worldwide among young and middle-aged people. The occurrence of renal dysfunction in cirrhosis of the liver is an integral part of the natural course of the disease. At the moment, the diagnosis of gender-specific renal dysfunction that occurs against the background of liver cirrhosis is essential for the development of effective treatment strategies and the improvement of survival.Objectives. The study is aimed at identifying the features of the gender-specific renal function and urinary syndrome in patients with liver cirrhosis of alcoholic etiology and assessing the comprehensive prognostic significance of the indicators of common urine analysis in the diagnosis of renal dysfunction.Methods. An observational study was carried out using data from medical records of 158 patients with alcoholic liver cirrhosis (95 men and 63 women), aged 36 to 72 years, who were inpatients between February 2016 and March 2020. Physical examination and laboratory diagnostic data were taken into account. Binary predictors of renal dysfunction progression in patients with alcoholic liver cirrhosis were determined based on the analysis of descriptive statistics. Statistical data processing was performed using computer program Statistica 10 (StatSoft, Inc., USA) and standard Microsoft Excel software package (Microsoft Office 2016). Non-parametric statistical methods were used to describe the results. Quantitative results were analyzed using the Mann-Whitney test; comparison of two samples by a qualitatively defined feature was performed by means of the Fisher angular transformation method. Differences were considered significant at p ˂ 0.05. A multilayer neural network function from the Statistica 10 Neural Networks software was used to construct a classification scheme for renal dysfunction (yes/no). Neural network performance was assessed using descriptive and inductive statistics, calculating sensitivity, specificity, performing ROC analysis and constructing cumulative gains charts.Results. A renal function test revealed a significant decrease in glomerular filtration rate (p = 0.029) and a significant increase in urinary albumin/creatinine ratio (p < 0.0001) in women with alcoholic liver cirrhosis as compared with men. Women are also reported to have a high incidence of proteinuria, leukocyturia and bacteriuria. According to ROC-analysis, the urinalysis indicators have a high prognostic significance in identifying renal dysfunction in men and women with alcoholic liver cirrhosis (AUROC = 0.902 and sensitivity 81.82%, AUROC = 0.881 and sensitivity 75.00%, respectively).Conclusion. Renal dysfunction develops earlier and occurs twice as often in women with alcoholic cirrhosis than in men of the same age. The application of a neural network mechanism to predict renal dysfunction in men and women with alcoholic liver cirrhosis according to the indicators of urinalysis provides a high prognostic ability

A procedure for the change point problem in parametric models based on phi-divergence test-statistics

This paper studies the change point problem for a general parametric, univariate or multivariate family of distributions. An information theoretic procedure is developed which is based on general divergence measures for testing the hypothesis of the existence of a change. For comparing the accuracy of the new test-statistic a simulation study is performed for the special case of a univariate discrete model. Finally, the procedure proposed in this paper is illustrated through a classical change-point example