Vitreous Gel Physics

The transparent vitreous, which fills the posterior cavity of the eye, is incredibly engineered. The charged polyelectrolyte hyaluronic acid (HA) network swells to maintain the pressure in the eye, while stiff collagen type II bundles help absorb any external mechanical shock. Our investigations have contributed to a few key developments related to the physical properties of the vitreous: (1) The stiff collagen network that supports the soft gel network is self-assembled from single triple-helix collagen proteins. Electrostatic interactions drive this assembly, such that the size and concentration are optimized at physiological salt concentrations. The width of the assemblies remarkably changes from 60 nm to 800 nm with only a 50 mM change in the salt concentration. (2) A soft (~ 2 - 200 Pa) negative polyelectrolyte network swells to support the microscopic and tough collagen bundles. The equilibrium swelling behavior and the response to external manipulation is driven by the charged components of the gel. We have developed a way to determine the thermodynamic quantities responsible for this phenomenon, such as the chemical miss-match parameter of the backbone, the ionizability of the network, and the Poisson ratio. We show that these parameters are enough to predict the equilibrium linear-elastic elasticity of polyelectrolyte gels for a range of strand lengths and salt concentrations. (3) Finally, using these principles, in collaboration with Dr. Paul Hamilton, and Dr. Nathan Ravi at Washington University, we have developed a new synthetic injectable vitreous substitute for use as a novel double-network therapeutic material. The vitreous can phase-separate and detach from the retina. This disease is poorly studied and has few treatment options. By studying biomimetic models of the vitreous in vitro, we hope to understand vision-related diseases, the mechanism for collagen fiber formation, intrinsic soft tissue properties, and to formulate therapeutic materials

Formation of foreign-language communicative competence at the scientific language lessons

The article proves that formation of foreign-language communicative competence is one of the core objectives of teaching Russian as a foreign language. The author proves that foreign-language communicative competence is a complex construct which includes linguistic, substantive, and pragmatic competences. Preparatory departments are to create an educational model that would provide formation of foreign-language communicative competence

The Creativity of Bernard Shaw in the Literary-Critical Perception of K.I.Chukovsky

The early reception of Bernard Shaw’s creativity is of considerable interest since it helps to characterise Russian-English historical, cultural and literary connections better, being an indicator of the impact of the aesthetics and drama by B. Shaw on creating a new drama and the development of Russian theatrical art. The research aims to examine the specific perception of the creativity of the English playwright B. Shaw by K.I. Chukovsky. The focus was mostly on the article Bernard Shaw from the series of Anglo-American notebooks, which analyses the works of the English playwright, as well as his aesthetic views, are fragmented. Thus, K.I. Chukovsky paid much attention to the ideological position of B. Shaw, which social-reformist trends in a society strongly influenced formation. In particular, he noted that the adoption of socialism by B. Shaw was slightly mental than emotional, correlated with the features of the social processes that were taking place. The article contained K.I. Chukovsky’s analysis of reviews of A.V. Lunacharsky on the works of B. Shaw and the statements of M. Gorky about paradoxes in English literature, fully characterising the attitude of social thought in Soviet Russia to the artistic legacy of the English playwright. It also reveals the specific understanding of the influence of creativity of G. Ibsen on theatrical innovations and aesthetic beliefs of B. Shaw, reflected in the essay Quintessence of Ibsenism. The role of the discussion as a structure-forming element in B. Shaw’s dramaturgy is defined.  Notes on individual plays by B. Shaw, presented in the works of K.I. Chukovsky, show that the plays of the playwright were accepted in the Russian cultural consciousness and were perceived in the light of the current social and literary trends

Rate of recovery of lichen-dominated tundra vegetation after overgrazing at the Yamal Peninsula ( Short Communication )

Lichens are the most sensitive part of vegetation cover to reindeer grazing. In this study we analyse success of restoration rate of lichen-rich tundra vegetation after ceasing the grazing stress at the Yamal Peninsula. On experimental plots we compare the main parameters of lichen mat (species diversity, total cover, thalii height, biomass, recovery rate) on grazed pastures and fanced sites after 13 years after of its isolation. Our results demonstrate that after intensive overgrazing the lichen species diversity and synusiases structure change very slowly. The rate of the biomass increase of lichens for this period has made 3.8 g m-2 year-1 that makes 3.6% from mass in the year. But this rate is two times lowers than in highly productive lichen communities

Salt marsh vegetation of the southern tundra subzone of Western Siberia: An example of the Baydaratskaya Bay coasts in the Kara Sea

The study is focused on the description of the vegetation and the general environment all characteristics of the salt marshes along coasts in the Baydaratskaya Bay there are of the Kara Sea in the southern tundra subzone of Russian Arctic. In tidal salt marsh habitats, several successional stages and types of communities depending on part of tidal zone. The plant communities study areas located close to research stations were represented by 50 species of vascular plant, 15 mosses and 3 lichens. The coastal vegetation tends to be floristically intermediate between the species composition of typical salt marshes communities (obligate and facultative halophytes) and species from adjacent tundra plains which can be able to tolerate occasional flooding by salt water. Zonation of salt marsh vegetation and floristic diversity were compared with the data for northern area of Kara Sea coasts

ФИГУРЫ ТАНАТОСА И ЭРОСА В ПОЭТИКЕ А. С. ПУШКИНА

The article deals with ontological issues of creativity and mortal implied sense of Pushkin's fairy tale. The study object is the figures of Thanatos and Eros in ‘The Tale of the Golden Cockerel’ fairy tale. The images of King Dadon and the Queen of Shamakhan are revealed in symbiotic relationship with folklore aesthetics. Reference to folklore is caused not only by genre of the work but also by metaphysical nature of oral tradition since the Russian people have a special attitude to the theme of death. This is evidenced by the Russian fairy tale with search of “the other kingdom” in which a hero must suffer a temporary death in order to get a wonderful object, save a prophetic bride and obtain the sacred knowledge.El artículo trata sobre cuestiones ontológicas de la creatividad y el sentido implícito mortal del cuento de hadas de Pushkin. El objeto de estudio son las figuras de Thanatos y Eros en el cuento de hadas "El cuento del gallo de oro". Las imágenes del rey Dadon y la reina de Shamakhan se revelan en una relación simbiótica con la estética del folklore. La referencia al folclore es causada no solo por el género de la obra sino también por la naturaleza metafísica de la tradición oral, ya que el pueblo ruso tiene una actitud especial hacia el tema de la muerte. Esto se evidencia en el cuento de hadas ruso con la búsqueda del "otro reino" en el que un héroe debe sufrir una muerte temporal para obtener un objeto maravilloso, salvar a una novia profética y obtener el conocimiento sagrado.В статье рассматриваются онтологические вопросы творчества, мортальный подтекст пушкинской сказки. Предметом исследования выступают фигуры Танатоса и Эроса в «Сказке о золотом петушке». Образы царя Дадона и Шамаханской Царицы раскрываются в неразрывной связи с фольклорной эстетикой. Обращение к фольклору обусловлено не только жанром произведения, но и самой метафизической природой устного народного творчества, так как русский народ особым образом относится к теме смерти. Об этом свидетельствует и русская волшебная сказка с поисками «иного царства», в которой герой обязательно должен пережить временную смерть, чтобы добыть чудесный предмет, выручить вещую невесту, приобщиться к сакральным знаниям

High-level laser therapy versus scalpel surgery in the treatment of oral lichen planus: a randomized control trial

Objective: To compare the clinical effectiveness of various types of high-level laser therapy (HLLT) toward scalpel excision for the surgical treatment of erosive oral lichen planus (OLP). Materials and methods: The total number of 128 individuals were enrolled in the study. The 35 did not meet the inclusion criteria due to malignancy signs and presence of diabetes mellitus. In total, 8 were lost to follow-up, and 10 were excluded from the analysis, due to analgesics intake. This way 75 patients with the erosive form of OLP were analyzed in three intervention groups (Er:YAG, n = 19; Nd:YAG, n = 15; Er:YAG + Nd:YAG combination, n = 20) and one control group with scalpel excision (n = 21). The therapy effectiveness has been assessed based on the comparison of salivary interleukin (IL)-1 beta, IL-6 and interferon (IFN)-gamma preoperative levels to 14, 30 days, and 2 years postoperation, as well as pain level and time of epithelization. Results: All HLLT groups demonstrated a significantly (p > 0.05) higher IL-1 beta, IL-6, IFN gamma and pain level reduction and quicker epithelization toward the control group on the 30th day, except Nd:YAG in case of IFN gamma level. The highest IL-1 beta, IFN gamma and pain level reduction and quicker epithelization on the 30th day was observed in Er:YAG group, followed by Er:YAG + Nd:YAG combination, Nd:YAG respectively. However no significant difference was observed between the HLLT groups with regard to IL-6 level reduction. After a 2-year follow-up, no significant difference was observed between all study groups with regard to all variables. Conclusion: HLLT yields a superior clinical outcome compared to the scalpel excision for the surgical treatment of oral lichen planus, whereby the Er:YAG has been proposed as the most effective laser type at the end of the first postoperative month. Clinical relevance: For the surgical treatment of erosive OLP the Er:YAG laser may be a preferable treatment option compared to Nd:YAG and scalpel surgery. Trial registration: The present trial was registered retrospectively in the German Clinical Trials Register, as a member of WHO international clinical trials registry platform, on the 18.03.2020 with the following number: DRKS00020986

Інноваційна модернізація економіки України з урахуванням досвіду ЄC

Introduction. At the beginning of the 21st century, most Western countries, faced with the need to find ways to grow, began to realize that the post-industrial economy can no longer act as a reliable foundation for economic development. It should be noted that Ukraine's place in world innovation processes does not yet match the potential of the country. Lack of funding for research and development, especially fundamental science, will lead to further outflow of highly skilled scientific personnel, loss of prospects for the growth of national competitiveness on world markets of innovative products and irreversible lagging behind developed countries. Aim and tasks. The aim of the research is to develop the general provisions of the systematic study of the patterns of innovation development of European countries in the context of global transformations and to justify on this basis the directions of innovation modernization of the Ukrainian economy. Results. Three fundamentally different variants of development of economic systems are determined depending on the choice of technological basis of economic growth. The prerequisites for formation of the strategy of innovation modernization of the Ukrainian economy are substantiated, namely: resource support; technological update; institutional support; development of infrastructure and regulatory support; strengthening of business reputation and access to the foreign market; increase of competitiveness of Ukrainian enterprises in the world market of goods and services. The model of innovative modernization of economic development with the account of the experience of the EU member states as a form of private-public partnership with the use of science-intensive technologies (on technological platforms) is offered. Conclusions. According to the results, it is determined that the effective system of innovative modernization of the Ukrainian economy has not yet been formed. The following areas are suggested for the urgent directions of solving this problem: fundamental development and theoretical substantiation of the types of public-private partnership; ensuring transparency of the system of stimulation of domestic innovation projects; formation of a stable information field, which includes a set of data on a number of issues that arise (between private, state and mixed structures), as well as in the process of generating and using financial resources for the purpose of innovative development of the domestic economy.Вступ. На початку ХХІ століття більшість західних країн, зіткнувшись з необхідністю пошуку шляхів економічного зростання, стали усвідомлювати, що постіндустріальна економіка більше не може виступати в якості надійного підґрунтя економічного розвитку. Необхідним базисом такого розвитку є матеріальне виробництво, традиційна зайнятість на підприємствах, які виробляють матеріальний продукт та в якому формується попит на інновації, що забезпечує динамічний розвиток інноваційної економіки. Слід зазначити, що місце України в світових інноваційних процесах поки не відповідає наявному в країні потенціалу. Недостатнє фінансування наукових досліджень і розробок, особливо фундаментальної науки, призведе до подальшого відтоку висококваліфікованих наукових кадрів, втрати перспектив зростання національної конкурентоспроможності на світових ринках інноваційної продукції та незворотного відставання від розвинених країн. Мета і завдання. Метою дослідження є розроблення загальних положень системного дослідження закономірностей інноваційного розвитку європейських країн в умовах глобальних трансформацій та обґрунтування на цій основі напрямів інноваційної модернізації української економіки. Результати. Визначено три принципово різних варіанти розвитку економічних систем в залежності від вибору технологічної основи економічного зростання. Обґрунтовано передумови формування стратегії інноваційної модернізації економіки України. Запропоновано модель інноваційної модернізації економічного розвитку з врахуванням  досвіду країн-членів ЄС як форми приватно-державного партнерства із застосуванням наукоємних технологій (на технологічних платформах). Висновки. За отриманими результатами визначено, що дієва система інноваційної модернізації економіки України ще не сформована. Актуальними напрямами вирішення цієї проблеми запропоновано такі: фундаментальна розробка і теоретичне обґрунтування видів державно-приватного партнерства; забезпечення прозорості системи стимулювання вітчизняних інноваційних проектів; формування стійкого інформаційного поля, що включає в себе сукупності даних по тих чи інших питань, а також в процесі генерування та використання фінансових ресурсів з метою інноваційного розвитку вітчизняної економіки

Fluid Separation and Network Deformation in Wetting of Soft and Swollen Surfaces

When a water drop is placed onto a soft polymer network, a wetting ridge develops at the drop periphery. The height of this wetting ridge is typically governed by the drop surface tension balanced by elastic restoring forces of the polymer network. However, the situation is more complex when the network is swollen with fluid, because the fluid may separate from the network at the contact line. Here we study the fluid separation and network deformation at the contact line of a soft polydimethylsiloxane (PDMS) network, swollen with silicone oil. By controlling both the degrees of crosslinking and swelling, we find that more fluid separates from the network with increasing swelling. Above a certain swelling, network deformation decreases while fluid separation increases, demonstrating synergy between network deformation and fluid separation. When the PDMS network is swollen with a fluid having a negative spreading parameter, such as hexadecane, no fluid separation is observed. A simple balance of interfacial, elastic, and mixing energies can describe this fluid separation behavior. Our results reveal that a swelling fluid, commonly found in soft networks, plays a critical role in a wetting ridge