Evaluation of the Humoral Immune Response to the Cytolethal Distending Toxin of Aggregatibacter Actinomycetemcomitans Y4 in Subjects with Localized Aggressive Periodontitis

Introduction Cytolethal distending toxin (Cdt) is potentially one of several virulence factors of Aggregatibacter actinomycetemcomitans, the prime etiological agent of localized aggressive periodontitis (LAP). Little is known regarding the Cdt-specific antibody response in humans. The current study is a quantitative and qualitative evaluation of the toxin-specific antibody response in a cohort of LAP patients and age-, race- and sex-matched controls. Methods Ninety-five subjects provided a total of 692 serum samples. Sera were analysed by enzyme-linked immunosorbent assays to determine the titers of antibody against the intact Cdt holotoxin as well as the individual subunit proteins (CdtA, CdtB, and CdtC). Neutralization of growth inhibition mediated by Cdt was evaluated in a modified colony-forming assay using Chinese hamster ovary cells. Results Fourteen of the 95 subjects exhibited significant serum Cdt-binding activity. There were no differences in the percentages of seropositive individuals or in the mean antibody titers between the control and LAP groups. Binding activity was detected against each of the three Cdt subunit proteins in all of the positive samples. Neutralization of Cdt-mediated growth inhibition was detected in samples from all of the seropositive subjects (range 20–75%). Conclusions Cdt, a recently identified A. actinomycetemcomitans virulence factor, is capable of inducing a neutralizing antibody response indicating that the toxin is produced during natural infection of humans. The failure of a vast majority (20 of 23) of the LAP subjects to mount a significant anti-Cdt response may in part explain their relative susceptibility to the disease

Classification of networks-on-chip in the context of analysis of promising self-organizing routing algorithms

This paper contains a detailed analysis of the current state of the network-on-chip (NoC) research field, based on which the authors propose the new NoC classification that is more complete in comparison with previous ones. The state of the domain associated with wireless NoC is investigated, as the transition to these NoCs reduces latency. There is an assumption that routing algorithms from classical network theory may demonstrate high performance. So, in this article, the possibility of the usage of self-organizing algorithms in a wireless NoC is also provided. This approach has a lot of advantages described in the paper. The results of the research can be useful for developers and NoC manufacturers as specific recommendations, algorithms, programs, and models for the organization of the production and technological process.Comment: 10 p., 5 fig. Oral presentation on APSSE 2021 conferenc

MACROECONOMIC INTERDEPENDENCE IN THE AGE OF GLOBAL VALUE CHAINS

The paper reviews the Conference on International Trade and Macroeconomic Interdependence in the Age of Global Value Chains that took place in Vilnius (Lithuania) in September 2016. The review deals with organisational and professional aspects of the Conference, and analyses main messages of the key speakers of the conference - Richard Baldwin (the concept of “unbundling”) and Marcel Timmer (the idea of decreasing intensity of international trade and defragmentation of international production). The paper includes author’s personal impression of the Conference

Evaluation of the Humoral Immune Response to the Cytolethal Distending Toxin of Aggregatibacter Actinomycetemcomitans Y4 in Subjects With Localized Aggressive Periodontitis

Introduction Cytolethal distending toxin (Cdt) is potentially one of several virulence factors of Aggregatibacter actinomycetemcomitans, the prime etiological agent of localized aggressive periodontitis (LAP). Little is known regarding the Cdt-specific antibody response in humans. The current study is a quantitative and qualitative evaluation of the toxin-specific antibody response in a cohort of LAP patients and age-, race- and sex-matched controls. Methods Ninety-five subjects provided a total of 692 serum samples. Sera were analysed by enzyme-linked immunosorbent assays to determine the titers of antibody against the intact Cdt holotoxin as well as the individual subunit proteins (CdtA, CdtB, and CdtC). Neutralization of growth inhibition mediated by Cdt was evaluated in a modified colony-forming assay using Chinese hamster ovary cells. Results Fourteen of the 95 subjects exhibited significant serum Cdt-binding activity. There were no differences in the percentages of seropositive individuals or in the mean antibody titers between the control and LAP groups. Binding activity was detected against each of the three Cdt subunit proteins in all of the positive samples. Neutralization of Cdt-mediated growth inhibition was detected in samples from all of the seropositive subjects (range 20–75%). Conclusions Cdt, a recently identified A. actinomycetemcomitans virulence factor, is capable of inducing a neutralizing antibody response indicating that the toxin is produced during natural infection of humans. The failure of a vast majority (20 of 23) of the LAP subjects to mount a significant anti-Cdt response may in part explain their relative susceptibility to the disease

Online-Shopping in the Culture of Nutrition of Modern Youth

В статье анализируются результаты пилотажного социологического исследования, направленного на изучение места online-покупок в системе культуры питания современной молодежи. В том числе оценивается распространенность использования сервисов доставки продуктов питания и готовой еды среди молодого поколения и факторы, определяющие выбор того или иного сервиса.The article analyzes the results of a pilot sociological research directed at studying the place of online shopping in the food culture system of modern youth. This includes assessing the prevalence of the use of food delivery services and ready-toeat meals among the younger generation and the factors determining the choice of one or another service

Chinese Automotive Companies in Russian Market: Penetration and Consolidation

The introducing of economic sanctions against Russia led to a massive exit of Western companies from the Russian market, which created favorable opportunities for expanding the activities of Chinese automobile companies. The aim of the paper is to identify the features of the activities of Chinese automakers, both those that have been present in the Russian market for a long time, and those entering it for the first time. According to the authors’ estimates, 38 Chinese companies (at the end of 2022) were present in the Russian market, which accounted to about 60 % of all operating Chinese automakers. As a result of the study, the authors proposed a classification of Chinese companies in the Russian market according to the method of market entering, which includes: “grey” exports, indirect exports through dealers and distributors, sales branches, foreign direct investment, portfolio investment. The authors come to the conclusion that indirect export, along with sales branches, is the most common way for Chinese automobile companies to enter the Russian market. At the same time, foreign direct investment is the most important method for strengthening Chinese companies’ position in the Russian automobile market. Companies such as Chery, Great Wall, and Geely are leaders among Chinese companies in sales in Russia: their total share is about 93 %, which means a high concentration of sales. A key feature of the activities of Chinese companies with foreign direct investment is the availability of powerful dealers’ network as well as the production of Chinese cars in joint ventures (brownfield investments), where the Russian company Avtotor plays a key role. The only exception is the Great Wall Motor company, which built the Haval plant in Tula “from scratch” (greenfield investment). The authors suggest that the small volumes of Chinese investment in the Russian automotive industry can be explained, among other things, by the predominance of brownfield investment over greenfield investment. Based on the study, the authors expect that the most important factors in the expansion of Chinese automobile companies in Russia will be the unfolding processes of digitalization, as well as the growing demand for electric vehicles. At the same time, Chinese automakers will have to face serious competition from both Russian and Korean companies

From colloidal CdSe quantum dots to microscale optically anisotropic supercrystals through bottom-up self-assembly

This is the author accepted manuscript. The final version is available on open access from Royal Society of Chemistry via the DOI in this recordThe development of fabrication techniques for novel nanostructured materials is one of the key tasks of modern materials science. One pathway to successfully complete this task is the bottom-up assembly of colloidal nanoparticles into ordered superstructures, possessing both the properties of individual nanoparticles and further novel properties resulting from their interactions. However, nanoparticle self-assembly depends on a variety of parameters, which makes the precise control of this process a complicated problem. Here, the time course of quantum dot (QD) self-assembly into ordered superstructures has been analyzed, along with the evolution of their morphological and optical properties. QD self-assembly occurs through two distinct stages (homo- and hetero-geneous), leading to the formation of supercrystals with a layered morphology. Analysis of the optical properties throughout the superstructures’ growth has shown that the absorption and photoluminescence (PL) bands are blue shifted, retaining almost the same PL lifetimes as in the initial QD solution. The supercrystals formed possess a further unique optical property caused by their layered morphology; namely, a four-fold symmetry characterized by strong birefringence. Such supercrystals may be used for the fabrication of microscale optical paths with high extinction coefficients and specific polarization properties for novel optoelectronic devices.This study was supported by the Ministry of Education and Science of the Russian Federation through the grant No. 14.584.21.0032 (ID RFMEFI58417X0032), the Engineering and Physical Sciences Research Council (EPSRC) of the United Kingdom via the EPSRC Centre for Doctoral Training in Electromagnetic Metamaterials (Grant No. EP/L015331/1) and via EP/N035569/1, and the Royal Society via International Exchange Grant No. 2016/R1

ОПРЕДЕЛЕНИЕ СИНТЕТИЧЕСКИХ КРАСИТЕЛЕЙ Е102, Е110, Е124, Е131 В ЙОГУРТЕ МЕТОДОМ ТВЕРДОФАЗНОЙ СПЕКТРОФОТОМЕТРИИ

Tartrazine E102, Yellow "Sunset" E110, Ponso 4R E124 and the Patented Blue E131 food synthetic dyes solid-phase extraction from yoghurts and biokefirs in a transparent polymethylmethacrylate matrix as a solid extractant was studied. The analytical signal was formed due to the accumulation of the dye in the volume of the polymer matrix without violating the transparency, and this corresponded to the wavelength of the maximum absorption of the corresponding dye. The sorption mechanism was based on the protonization of the carbonyl groups of PMM in the acidic media, and, as a result, the optode surface became positively charged. Therefore, the sorption of the R± form of the E131 dye and the azo dye anions occurred by the positively charged PMM surface. The effectiveness of the proposed approach was shown for the identification and determination of the 2 food-grade synthetic dyes content using the visual and spectrophotometric methods. The optimal conditions for the analysis corresponded to pH 3, the duration of dye extraction into the polymer matrix was 20 min, the range of the detected concentrations was 0.2–40.0  mg / kg with the detection limit of 0.05 mg/kg, and an excess of sweeteners and preservatives did not significantly affect the results of the analysis. The results of the determination of the listed dyes were demonstrated in the current work for the case of individual and group presence of dyes in biokefirs and yogurts. The proposed technique is simple in execution and could be carried out using the standard spectrophotometric equipment. The advantage of the developed method for the determination of artificial dyes in comparison with the method of spectrophotometric determination with liquid extraction is a significant increase in the sensitivity of determination due to the accumulation of analyte, the exclusion of turbidity of an aliquot and the absence of dye loss due to its transition into the supernatant, and then into the solid phase of the matrix.Keywords: colorimetric sensor, solid-phase spectrophotometry, polymethylmethacrylate matrix, synthetic food colorant, dairy productDOI: http://dx.doi.org/10.15826/analitika.2020.24.1.002  A.A. Dudkina1, N.V. Saranchina1, T.N. Volgina1, N.A. Gavrilenko2, M.A. Gavrilenko11Tomsk Polytechnic University, 30 Lenin Ave, Tomsk, 634050, Russian Federation2Tomsk State University, 36 Lenin Ave, Tomsk, 634050, Russian FederationИзучена твердофазная экстракция пищевых синтетических красителей тартразин Е102, желтый «солнечный закат» Е110, понсо 4R Е124 и патентованный синий Е131 из йогуртов и биокефиров в прозрачную полиметилметакрилатную матрицу в качестве твердого экстрагента. Аналитический сигнал формируется вследствие накопления красителя в объеме полимерной матрицы без нарушения прозрачности и соответствует длине волны максимума поглощения соответствующего красителя. Механизм сорбции основан на том, что в кислых средах карбонильные группы ПММ способны подвергаться протонизации, за счет этого поверхность оптода становится положительно заряженной. Таким образом, происходит сорбция R± формы красителя Е131 и  анионов азокрасителей положительно заряженной поверхностью ПММ. Показана эффективность предложенного подхода для идентификации и определения содержания двух пищевых синтетических красителей визуальным и спектрофотометрическим методом. Найдены оптимальные условия проведения анализа: рН 3, продолжительность экстракции красителей в полимерную матрицу 20 минут, диапазон определяемых концентраций 0.2–40.0 мг/кг с пределом обнаружения 0.05 мг/кг, избыток подсластителей и консервантов не оказывает существенного влияния на результаты анализа. Приведены результаты определения перечисленных красителей, в том числе при их совместном присутствии в образцах биокефиров и йогуртов. Методика осуществляется на спектрофотометрическом оборудовании, либо простой полуколичественной визуальной оценкой. Преимуществом разработанной методики определения искусственных красителей по сравнению с методом спектрофотометрического определения с жидкостной экстракцией является значительное повышение чувствительности определения вследствие накопления аналита и исключения мутности аликвоты, а также отсутствие потерь красителя вследствие его перехода в надосадочную жидкость и, затем, в твердую фазу матрицы.Ключевые слова: колориметрический сенсор, твердофазная спектрофотометрия, полиметилметакрилатная матрица, синтетический пищевой краситель, молочный продуктDOI: http://dx.doi.org/10.15826/analitika.2020.24.1.00

Peculiarities of the paradoxes of Oscar Wilde

The aim of study - on the basis of perused aphorisms of O. Wilde to prove that Oscar Wilde's paradoxes due to their peculiarities can be regarded as a special category of paradoxesЦель исследования - на основе сбора и анализа афоризмов Оскара Уйальда показать особенности парадоксов автора, позволяющие выделить их в определенную категорию