457 research outputs found

    Prevention method of toric intraocular lens rotation after phacoemulsification of cataract using a standard capsule ring

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    At the same time, phacoemulsification of cataracts remains the most popular surgery. But the problem among phacosurgeons is the correction of existing corneal astigmatism. According to studies, about 30% of the world's population have corneal astigmatism with a strength of 0.75D and above, which leads to a decrease in visual acuity after phacoemulsification of cataracts in the absence of its correction.The most commonly used method to correct corneal astigmatism is the implantation of toric intraocular lenses (TIOL). The main condition for obtaining high visual acuity after TIOL implantation is the location of the astigmatic component of the artificial lens in accordance with the strong meridian of the cornea. The aim of this study was to evaluate the effectiveness of the proposed method of preventing the toric intraocular lens rotation after phacoemulsification of cataracts in the eyes with corneal astigmatism by implantation of a standart capsule ring.Material and methods. The article presents the results of a comprehensive examination of 43 patients (59 eyes) who underwent surgery by phacoemulsification of cataracts with implantation of toric IOL to correct concomitant corneal astigmatism. Corneal astigmatism according to keratometry ranged from 0.5D to 4.25D (average 1.96 ± 0.1 D). Patients were divided into 2 groups. The first group consisted of 26 patients (31 eyes). Patients in this group underwent phacoemulsification with toric IOL implantation according to standard techniques without the use of techniques that prevent rotation of the artificial lens in the postoperative period. The second group included 18 patients (28 eyes) who were operated on according to our proposed prevention method of TIOL rotation. As a result of the study, it was found that rotation of TIOL was detected 6 months after surgery in the I group without the use of developed method in 22 eyes (70.9%), in the II group, where the capsule ring was implanted, rotation occurred in 12 eyes (42.85%). In the II group in all cases, the deviation of the TIOL axis did not exceed 6 degrees. The proposed method of prevention of rotation of TIOL allows to increase the efficiency of phacoemulsification of cataracts.Conclusions. Developed a method of preventing the rotation of the toric intraocular lens using a standard capsule ring, which is implanted and located on top of the haptic support elements of the artificial lens can increase the efficiency of phacoemulsification of cataracts in the eyes with corneal astigmatism, contributes to the rotational stability of the toric lens and provides long-term results of visual functions, reduces the need for repeated surgery due to reposition of the rotated lens and can be recommended for implementation in the practice of ophthalmic surgeons.The use of implantation of a standard capsule ring according to the proposed in this study method prevents the rotation of the toric intraocular lens by more than 6 degrees in all cases, which does not significantly reduce visual acuity and does not require reposition of the artificial lens. This method of preventing rotation of the toric intraocular lens allows to achieve visual acuity of 0.7 and above in 85.6% of cases

    Forming Professionally Important Qualities of Students of Non-Linguistic Universities by Means of the “Foreign Language” Discipline

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    The article focuses on searching for new, optimal means of forming professionally important qualities of students of non-linguistic universities using the discipline “Foreign language” on the example of the experience of Moscow Agricultural Academy named after K. A. Timiryazev. The study of a foreign language in a non-linguistic university makes an undeniable contribution to the process of personality selfdetermination. The study aims to determine effective teaching methods and formulating professionally important personality traits of future engineers. These methods are formed in educational quasiprofessional activity and are improved in the process of professional activity as professionalization and based on the experience of applying skills. We correlate the main types of educational activity with the professionally important personality traits of future specialists that are functionally differentiated according to three subsystems of the personality structure-cognitive, communicative, and regulatory. This approach is innovative in teaching practice. The study includes the development of recommendations for optimizing their formation in learning a foreign language

    Formation of Optical Low-dimensional Structures for Photonic Elements

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    In the present article, the formation of low-dimensional periodic structures with relief repeating the trajectory of movement of an AFM probe were presented. The parameters affecting their geometric dimensions: height, width, uniformity in the layer, etc., were investigated. The method of induced deposition of silver and/or gold clusters on the surface of a Bragg mirror in the presence of an external electric field was developed. The possibility of using such structures in optical elements, photoelectronic converters, optoelectronic devices of fiber optics, as well as the construction of photonic crystals (elements) based on the periodic structures is discussed.     Keywords: nanostructures, the atomic force microscope (AFM), the probe lithograph

    ПСИХОЛОГО-ПЕДАГОГІЧНІ ОСОБЛИВОСТІ РОЗРОБКИ ДИСТАНЦІЙНОГО НАВЧАЛЬНОГО КУРСУ З ДИСЦИПЛІНИ «ПСИХОЛОГІЧНЕ КОНСУЛЬТУВАННЯ»

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    Розглянуто проблему психолого-педагогічного забезпечення організації матеріалів дистанційних навчальних курсів на прикладі розробленого авторського модуля до курсу «Психологічне консультування»

    Forecast for the zone of viticulture in European Russia under climate change

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    Climate warming has turned out to be a significant factor in viticulture and winemaking in all grape-growing areas of the world. Many countries consider the advance of viticulture to the north and to mountainous areas as a possible way to adapt to warming. The factors limiting the zone of viticulture in Russia have been identified by Soviet scientist F.F. Davitaya in 1948, and they are still relevant. They are the sum of active temperatures above 10 °C (ΣT10 > 2500 °C), mean of absolute minimum temperatures (Tmin > –35 °C), length of the frost-free period (Lff < 150 days), and hydrothermal coefficient (0.5 < HTC < 2.5). The values of these limiting factors in the present-day zone of commercial viticulture (ZCV) correspond to the ranges defined by F.F. Davitaya, with the exception of Tmin, which in the modern ZCV in European Russia is above –26 °C everywhere. The objective of this work was to assess the possibility of moving the boundaries of the ZCV to the north under the existing and predicted climate conditions in European Russia. The 1980–2019 daily data from 150 weather stations of the Federal Service for Hydrometeorology and Environmental Monitoring were used to calculate mean long-term values, trends and forecasts for 2050 for the ZCV limiting factors and locate the points lying in the range acceptable for viticulture. The QGIS program was applied to plot the points on the European Russia map and mark the terminal latitude. Versions with Tmin > –26 °C and Tmin > –35 °C were considered. On average for European Russia, in 1980–2019, there was an increase in ΣT10, Tmin, and Lff and a decrease in HTC. However, in the same period, Tmin showed a tendency toward decreasing at a number of points at latitudes lower than 55° N. The increase in heat supply during the growing season in European Russia implies a possibility of expanding the ZCV northward, beyond the present-day terminal latitude of 46.6° N, to 51.8° N under the existing conditions, and up to 60.7° N by 2050. In addition, even under the current conditions viticulture is possible in the area of Kaliningrad (54° N, 20° E). Using extra protective measures in winters not colder than –35 °C would make it possible to grow grapes at up to 53.3° N under the current conditions and at up to 60.7° N under the prognosticated ones. At the same time, a possible decrease in the minimum winter temperature at the south of European Russia will require additional protective measures in winter, while an increase in the aridity of the climate on the northwest coast of the Caspian Sea will reduce the area under non-irrigated vineyards

    Legends and Myths of Online Testing: The Truth is Out There

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    The article discusses the prospects of the remote format for assessing competencies through a comparative analysis with the development of classical chess, concludes that it is necessary to rethink the role and place of online testing

    Staff Week as a Modernization Tool in Translator Training Programs: Experience of Cooperation in the Erasmus +

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    Translator training in the coordinates of the global educational space implies an integrative approach to unification and at the same time extension of theoretical, methodological and didactic approaches. At the same time, the search for effective ways and tools of interaction is carried out at different levels – academic, professional communities, individual persons, since the profession of a translator implies communication without borders, networking and constant expansion of the circle of partnerships. This article analyzes the effectiveness of one of the current tools for interuniversity cooperation in the format of Staff Week internships, integrated into the Erasmus + academic mobility program, in the focus of its validity and functionality in training translators. The study provides an analysis of domestic and foreign scientific and educational works on the scientific, didactic potential of the program, a review of the current state of affairs in the field of intercollegiate cooperation within Erasmus + on the example of the Russian university – Volgograd State University and the German university – International University SDI Munich. These universities have been developing partnership relations since the 90s, however, Erasmus has been cooperating with them recently and quite successfully. The material of the study is an overview of the structure and content of the Staff Week internships of Volgograd State University teachers at SDI Munich. The Intercultural component of interaction is effectively manifested in the optimization of didactic models in the partner university, updating of curricula, expanding the horizons of joint projects, which certainly contributes to improving the quality of educational services in the field of translation and promotes the integration of education in general. The results of this research can be useful for the organization of the educational process in university educational programs in the areas of training specialists in the field of translation and intercultural communication

    On the nature of picobirnaviruses

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    The picobirnaviruses (Picobirnaviridae, Picobirnavirus, PBVs) are currently thought to be animal viruses, as they are usually found in animal stool samples. However, no animal model or cell culture for their propagation has yet been found. In 2018, a hypothetical assumption about PBVs belonging to prokaryotic viruses was put forward and experimentally substantiated. This hypothesis is based on the presence of Shine–Dalgarno sequences in the genome of all PBVs before three reading frames (ORF) at the ribosomal binding site, with which the prokaryotic genome is saturated, while in the eukaryotic genome such regions occur with low frequency. The genome saturation with the Shine–Dalgarno sequences, as well as the preservation of this saturation in the progeny, according to scientists, allows us to attribute PBVs to prokaryotic viruses. On the other hand, there is a possibility that PBVs belong to viruses of eukaryotic hosts – fungi or invertebrates, since PBV­like sequences similar to the genome of fungal viruses from the families of mitoviruses and partitiviruses have been identified. In this regard, the idea arose that, in terms of reproduction mode, PBVs resemble fungal viruses. The divergence of views on the true PBV host(s) has sparked discussions among scientists and required further research to elucidate their nature. The review highlights the results of the search for a PBV host. The reasons for the occurrence of atypical sequences among the PBV genome sequences that use an alter­ native mitochondrial code of lower eukaryotes (fungi and invertebrates) for the translation of viral RNA­dependent RNA polymerase (RdRp) instead of the standard genetic code are analyzed. The purpose of the review was to collect arguments in support of the hypothesis about the phage nature of PBVs and to find the most realistic explanation of the reasons for identifying non­standard genomic sequences for PBVs. Based on the hypothesis about the genealogical relationship of PBVs with RNA viruses from other families with similar segmented genomes, such as Reoviridae, Cystoviridae, Totiviridae and Partitiviridae, virologists support the assumption of a decisive role in the origin of atypical PBV­like reassortment strains between PBVs and viruses of the listed families. The collected arguments given in this review indicate a high probability of a phage nature of PBVs. The data presented in the review show that the belonging of PBV­like progeny to prokaryotic or eukaryotic viruses is determined not only by its genome saturation level with a prokaryotic motif, standard or mitochondrial genetic code. The primary structure of the gene encoding the viral capsid protein responsible for the presence or absence of specific proteolytic properties of the virus that determine its ability for independent horizontal transmission into new cells may also be a decisive factor

    Picobirnaviruses: prevalence, genetic diversity, detection methods

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    This article presents a general overview of the prevalence, genetic diversity and detection methods of picobirnaviruses (PBVs), which are small, non-enveloped icosahedral viruses with a segmented double-stranded RNA genome consisting of two segments taxonomically related to the genus Picobirnavirus of the family Picobirnaviridae. This review of scientific papers published in 1988–2019 provides data on the PBV distribution in the nature and a broad host range. PBV infection is characterized as opportunistic, the lack of understanding of the etiological role of PBVs in diarrhea is emphasized, since these viruses are detected both in symptomatic and asymptomatic cases. The concept of PBV infection as a chronic disease caused by a long-lasting persistence of the virus in the host is considered. Such factors as stress syndrome, physiological conditions, immune status and host age at the time of primary PBV infection influence the virus detection rate in humans and animals. The possible zoonotic nature of human PBV infection is noted due to the capacity for interspecies PBV transmission acquired during evolution as a result of the reassortment of the genome segments of different viruses infecting the same host. Data providing evidence that PBVs belong to eukaryotes and a challenging hypothesis stating that PBVs are bacterial viruses are presented. The need to intensify work on PBV detection because of their wide distribution, despite the complexity due to the lack of the cultivation system, is emphasized. Two strategies of RT-PCR as main PBV detection methods are considered. The genomes of individual representatives of the genus isolated from different hosts are characterized. Emphasis is placed on the feasibility of developing primers with broader specificity for expanding the range of identifiable representatives of the genus PBV due to a huge variety of their genotypes. The importance of effective monitoring of PBV prevalence for studying the zoonotic and anthroponotic potential using metagenomics analysis is highlighted, and so is the possibility of using PBV as a marker for environmental monitoring

    Ranking of spring bread wheat genotypes according to the heading date and growing season duration in different ecogeographic environments

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    Background. Adaptation of spring bread wheat cultivars to climate change requires a study of the factors affecting the length of their growing season in various environments. An attempt is made to analyze regularities in the effect of ecogeographic conditions on the correlations shown by the duration of the growing season and interphase periods in spring bread wheat genotypes.Materials and methods. Correlation coefficients were studied for the impact of the environment and temperature on the duration of the interphase periods from sprouting to heading (SH) and from heading to yellow ripeness (HR) versus the period from sprouting to yellow ripeness (SR) in VIR’s wheat collection across 18 sites located in Russia and Uzbekistan from 41 to 60°N and from 30 to 135°E. The effect of the genotype and year on SH and HR was studied, and agrometeorological regression models of SH and HR were constructed, based on the data obtained during the studies of the collection in St. Petersburg in 1945–2021.Results. For the sites below 52–54°N, the SR/SH correlation coefficient was generally higher than SR/HR, and in the upper latitudes it was vice versa. The change in the ratio of coefficients occurred due to an increase in the interannual variability of HR at lower temperatures. The effect of HR on SR became greater than that of SH at temperatures below 18°С during HR. The data of a long-term study in St. Petersburg demonstrated that the effect of the genotype on SH was 18.9%, with 68.9% of the year, and the effect of the factors on HR was 4.1 and 71.3%, respectively. Regression models showed that HR was determined by temperature for at least 81%, while SH had a lower coefficient of determination by weather (56%).Conclusion. Ranking of wheat genotypes according to their heading time reflected their differentiation in earliness. A significant contribution of HR was conspicuous under temperatures below 18°C after heading at latitudes above 52–54°N
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