Synthesis Strategy of Tetrapyrrolic Photosensitizers for Their Practical Application in Photodynamic Therapy

This review presents a wide range of tetrapyrrole photosensitizers used for photodynamic therapy (PDT), antimicrobial photodynamic therapy, photoinactivation of pathogens. Methods of synthesis and design of new photosensitizers with greater selectivity of accumulation in tumor tissue and increased photoinduced antitumor activity are considered. The issues of studying the properties of new photosensitizers, their photoactivity, the ability to generate singlet oxygen, and the possibility of using targeted photodynamic therapy in clinical practice are discussed. The review examines the work on PDT by national and foreign researchers.

A NUMERICAL SET-UP FOR THE SIMULATION OF INFECTION PROBABILITY FROM SARS- COV-2 IN PUBLIC TRANSPORT VEHICLES

In this work, a numerical framework aimed at simulating the transport of contaminants and infectious agents within a closed domain is presented. The method employs mature CFD algorithms to calculate air fields with reasonable computational costs. The main objective is to give fast response to stakeholders about air quality indicators in the design phase of HVAC systems. A discussion regarding the size and characteristics of different contaminants is proposed, highlighting the most appropriate methods and coefficients needed to simulate their transport. Next, the methodology employed to evaluate the risk of infection is presented. The numerical set-up, based on the buoyantBoussinesqPimpleFoam solver in OpenFOAM, was tuned by simulating the well-known case of the heated floor cavity, providing accurate results. Hence, the case study of a transport vehicle of generic shape is presented, in order to show possible results in terms of air-age distribution, PM2.5 distribution, and global infection risk matrix. © 2022, Scipedia S.L. All rights reserved.

Innovative Solutions in the Tourism and Hospitality Industry to Ensure Sustainable Development in a New Normality

The article examines topical issues of the functioning of the tourism and hospitality industry in the context of the new normalcy caused by the COVID-19 pandemic. The pandemic has led to a sharp decline in tourist flows and the need for innovative solutions to restore and further develop the tourism and hospitality industry. In the context of the new normality, the classical interpretation of the concept of the quality of tourist and hotel services and sustainable development of tourism is changing. When assessing the quality of services in tourism, the assessment of their epidemiological safety began to occupy a key place. The sustainable development of tourism is significantly influenced by global digitalization and the formation of a new category of digital tourists. The article analyzes innovative solutions to ensure travel safety and sustainable development of the tourism industry in the context of the new normalcy. It is shown that in the context of a pandemic, there was an acceleration of the processes of introducing innovations, including digitalization in the field of tourism. It is proposed to expand the understanding of sustainable tourism development by including digital information support as a prerequisite for meeting the requirements of digital tourists.

Characteristics of X-ray pattern of lung lesion in COVID-19 in adult patients with cystic fibrosis

Background. Patients with cystic fibrosis (CF) fall into the risk group of breathing passages infection as a result of clinical features of the disease. During the period of COVID-19 pandemic,the necessity of understanding how infection affects the course of the main disease has appeared, taking into account that viability of patients is essentially determined by the degree of lung lesion. Early diagnostics and complex therapy of coronavirus infection increase the lifespan of CF patients and improve quality of life. X-ray examinations play the leading role in solving this problem. Purpose – to establish risk factors of the main pathological process aggravation by determining diagnostic significance of roentgen sings of lung lesion in COVID-19 in CF adult patients. Materials and methods. Theanalysis of radiography and computed tomography results of 11 adult patients with CF of moderate and severe degree who were also diagnosed with coronavirus infection. Results. The main X-ray symptoms in observed patients with CF with confirmed diagnosis of coronavirus infection was pneumonic infiltration of different degrees in the setting of diffuse changes of lung pattern and features of pulmonary emphysema. Besides symptoms of the main disease, computed tomography allowed us to find the signs, which we consider to be the signs of pneumonia caused by COVID-19 infection – induration of lung tissue in the form of ground-glass opacity, presence of ground-glass areas of different shapes with reticular changes and consolidation of lung tissue, bilateral localization of pathological changes, predominantly in basal and subpleural areas. Conclusions. Lung lesion conditioned by COVID-19 in radiography of CF patients may be disguised by the features of the main disease manifestations. Therefore, any X-ray evidence of inflammatory lung changes in CF patients during the epidemic period must be regarded as COVID-19 suspected, and polymerase chain reaction and computed tomography must be performed. © Tkachenko M.M., Morozova N.L., Tanasichuk-Gazhyeva N.V., Cherkasova L.A., 2022.

The Problems of the COVID-19 Pandemic in Higher Education

Since the outbreak of the pandemic COVID-19, many studies have been conducted to examine how education has responded to the challenges of a completely new situation that has led to the spread of distance education as the only form of instruction. In this study, data were collected and analyzed to understand the difficulties of distance education that higher education students faced during the pandemic. Our goal was to present the results of a socio-psychological study of accessibility, educational resources, applications, and distance learning technologies. A total of 160 students from different Moscow universities participated in the study. A qualitative research method was used for the study. For this purpose, mainly in-depth interviews were conducted to find out the participants' views on distance education. The data obtained were analyzed by the researchers using qualitative analysis methods. The results showed that all students faced technical difficulties during distance learning, such as poor internet connection, lack of access to online platforms due to the high number of users, lack of necessary equipment, and individual space for online learning. The results also showed low technical readiness for distance education and low quality of online resources, as well as cyber threats during online courses. In addition, the results showed that most students indicated that they would prefer a hybrid form of instruction that combines distance and face-to-face instruction. Implications for further studies are drawn in the conclusion.

The study protocol: COVID-19 awareness and perception among dentists in the Russian Federation.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) has spread rapidly worldwide since it has been first identified in November 2018. It is transmissible via air droplets from infected individuals. Close contact between dentists and patients has aggravated the pandemic situation in Russia. It is necessary to reduce the risk of spreading COVID-19 during dental appointments by adhering to the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) recommendations. SUBJECTS AND METHODS: Questionnaires were developed to assess levels of COVID-19 infection and preventive measures in private and state-funded dental practices in Moscow and other cities in Russia. Two questionnaires were developed to assess the COVID-19 situation among dental professionals and their patients. The first, for dentists, included four domains: demographic data, signs, and symptoms of COVID-19 experienced by dentists, personal protective measures taken by dentists, and presence or absence of dental practice during the pandemic. For dentists' patients, the second included domains regarding their health status after their dental appointment. 1,500 questionnaires were sent to different cities and regions of Russia; 1,011 questionnaires (67.4%) were returned. We used statistical observation (monitoring) and clustering to analyze the data. The x2 was used to check the significance level. RESULTS: We found a direct relationship between those patients who contracted COVID-19 after dental treatment by those dentists who did not follow recommended measures in the dental clinic. However, patients were less likely to become infected after dental treatment by those dentists who followed the measures, such as the disinfection of surfaces and dental equipment several times a day, the wearing of medical masks by all patients, and the airing of the dental office after each patient for 10 minutes. CONCLUSIONS: Dentists wearing an FFP2 or FFP3 respirator, as well as a sterile disposable microfiber medical gown, prevented their patients from becoming infected with COVID-19 at dental appointments and, as a result, the spread of the virus. A key aspect of this study is its knowledge regarding preventive measures against COVID-19. The findings of this study can potentially help in formulating strategies to reduce the prevalence of COVID-19.

HERD IMMUNITY to SARS-CoV-2 among the POPULATION of the REPUBLIC of BELARUS AMID the COVID-19 PANDEMIC

The Bioethics Committee of Belarus and the local ethics committee of the St. Petersburg Pasteur Institute approved the study. Selection of participants was carried out using a questionnaire method and online technology (internet, cloud server). Volunteers were randomized into seven age groups (years of age): 1–17;18–29;30–39;40–49;50–59;60–69;and 70+. Regional randomization ensured proportional representation of volunteers from each region, and no more than 30 people were included from one enterprise. In accordance with manufacturer instructions, blood plasma samples were analyzed for: IgG antibodies (Abs) to the SARS-CoV-2 nucleocapsid (Nc) using a quantitative ELISA test system;and IgG Abs to the receptor binding domain (RBD) of the SARS-CoV-2 S (spike) surface glycoprotein using a qualitative ELISA test system. Statistical processing was carried out using Excel 2010 and other software. Statistical differences were designated as significant when p < 0.05, unless otherwise indicated. Results. The level of seroprevalence, in terms of Abs to Nc among the Belarusian population, was 38.4% (95% CI 37.6–45.4). The highest Ab levels were found among individuals in older age groups (50-70+ years old). The lowest were found in children 1–17 years old and in young people 18–39 years old The distribution of seroprevalence across Belarusian regions was relatively homogeneous, with the exception of the Minsk Region, where a statistically significant decrease in the indicator was noted. In terms of profession, the largest share of seropositive individuals was found among transportation workers;the smallest was found in business. The moderate COVID-19 incidence has not led to a dramatic increase in the number of contacts. The base reproduction number (R0) was 1.3. In the Republic of Belarus, there was a moderate level of asymptomatic COVID-19 among seropositive individuals (45.3% [95% CI 44.0–46.7]). This form of infection was observed most often among children aged 1–17 years old (65.0% [95% CI 61.3–68.6]). In parallel with seroprevalence assessment, SARS-CoV-2 vaccination was carried out. We used two vaccines: Gam-COVID-Vac (also known as Sputnik V, developed by Gamaleya National Center for Epidemiology and Microbiology, Russia);and BBIBP-CorV (Sinopharm, PRC). Vaccination against SARS-CoV-2 was accompanied by an increase in the level of anti-RBD Abs (95% [95% CI 94.7–96.7]). Taking into account the vaccination of a subset of the population with BBIBP-CorV, the overall herd immunity, inferred from the analyzed indicators (presence of anti-Nc or anti-RBD Abs), was 47.1% (95% CI 46.3–48.0). Conclusion. COVID-19 in Belarus was characterized by a moderately pronounced course of the epidemic process. The threshold level of herd immunity to SARS-CoV-2 has not yet been reached, as a result of which the conditions for progression of the epidemic remain.

Regional Features of Development of Tourism Infrastructure and Their Impact on Tourism

Introduction. Tourism activities are important development drivers of regional economies. Regional tourism has gained special significance in the last year, when restrictions on international travel caused by the COVID-19 pandemic diverted tourist flows to domestic travel. The research topic is of relevance because of the peculiarities and uneven development of tourism and tourism infrastructure in different regions of Russia and because of the need to identify the causes and consequences of the emerging imbalances. Based on the results of the conducted research, the article identifies the regional features of development of tourism infrastructure and the factors affecting them. Materials and Methods. The study was based on the analysis of official statistical data from Russian Federal State Statistics Service and the Federal Agency for Tourism regarding the development of tourism and tourism infrastructure in the federal districts of the Russian Federation. To identify the level of development of the tourism infrastructure, economic and statistical methods were used, as well as specific indicators characterizing the tourist infrastructure, including the Baretje-Defert and Schneider indices, etc. A horizontal and structural analysis of statistical data on the development of tourism and its infrastructure was carried out, which made it possible to identify the features of regional development of tourism infrastructure. Results. The authors have analyzed statistical data characterizing tourism activities, studied regional imbalances in the development of tourism infrastructure, identified the causes and consequences of uneven development of regional infrastructural support for tourism activities, and formulated proposals for taking them into account when developing strategic master plans for development of tourist areas. Discussion and Conclusion. The results obtained can be used when devising strategies for development of regional infrastructural support for tourism activities, as well as when preparing master plans for tourist destinations, which will contribute to increasing the scientific validity of managerial decisions regarding tourism development at the regional level.

Case of lethal outcome of an infant due to CoVID-19

The article presents clinical data and the results of a detailed pathology changes in a 2-month-old infant who died from a coronavirus infection, confirmed by the results of in vivo PCR and morphological examination, which included the detection of the SARS-Cov-2 spike antigen. Histological examination in the lungs, as well as in the brain revealed cytoproliferative and cytopathic changes similar to those described in coronavirus infection in adults, while other characteristic for them lesions were not determined. The unfavorable course of COVID-19 was facilitated by an activated intrauterine infection, mycoplasmosis or chlamydiosis according to morphological data.

The crisis of education in conditions of the covid-19 pandemic: The model of blended learning

Purpose of the study: The paper presents a topical problem of modern higher education in the context of the transition to distance learning for the period of active spread of the coronavirus COVID-19. To date, a decision has been made to partially or completely close schools and universities in 191 countries around the world. As a result, about 1.6 billion students switched to distance education. In this connection, today this area of the system of education is of the highest importance, both for individual countries and for the entire world community. Methodology: The leading approach to the study of the problem of distance learning in the system of higher professional education was a systematic approach as a methodological principle of modern science. The scientific and theoretical teachings about distance learning, the distance learning technology, the model of blended learning in higher education;theoretical propositions on the methods and technologies of providing distance learning in higher education became the fundamental basis of this study. Results: The paper presents the study results of the most relevant trends in education: Omni-learning (learning with the use of all possible communication channels), adaptive learning, distance learning, online mentoring, blended learning, "self-learning" organizations, EdTech startups, etc. The results of a comparative analysis of traditional forms of learning and blended learning are presented. It has been proven that blended learning is the most effective form of distance learning. Application of this study: We can conclude that in the current socio-economic conditions of the development of the system of higher professional education, the introduction of a blended learning model in the framework of the conception of lifelong education seems to be necessary and obvious in our opinion. Proceeding from this conception, specialists of any profession need continuous improvement of knowledge, skills, professional competencies, which is possible in the framework of the blended learning model using e-learning technologies. Novelty / originality of this study: The conclusions have been made that blended learning makes it possible to translate the learning process into the information space;contribute to the formation of the learner's competencies stipulated in the Federal State Educational Standard and also creates the conditions for the development of readiness and the student's ability to selfactualize.