Assessment of the Bankruptcy Risk in the Hotel Industry as a Condition of the COVID-19 Crisis Using Time-Delay Neural Networks

In this paper we demonstrate a new conceptual framework in the application of multilayer perceptron (MLP) artificial neural networks (ANNs) to bankruptcy risk prediction using different time-delay neural network (TDNN) models to assess Altman's EM Z″-score risk zones of firms for a sample of 100 companies operating in the hotel industry in the Republic of Serbia. Hence, the accuracies of 9580 forecasting ANNs trained for the period 2016 to 2021 are analyzed, and the impact of various input parameters of different ANN models on their forecasting accuracy is investigated, including Altman's bankruptcy risk indicators, market and internal nonfinancial indicators, the lengths of the learning periods of the ANNs and of their input parameters, and the K-means clusters of risk zones. Based on this research, 11 stability indicators (SIs) for the years under analysis are formulated, which represent the generalization capabilities of ANN models, i.e., differences in the generalization errors between the preceding period and the year for which zone assessment is given;these are seen as a consequence of structural changes at the industry level that occurred during the relevant year. SIs are validated through comparison with the relative strength index (RSI) for descriptive indicators of Altman's model, and high correlation is found. Special focus is placed on the identification of the stability in 2020 in order to assess the impact of the COVID-19 crisis during that year. It is established that despite the fact that the development of bankruptcy risk in the hotel industry in the Republic of Serbia is a highly volatile process, the largest changes in the analyzed period occurred in 2020, i.e., the potential applications of ANNs for forecasting zones in 2020 are limited. © 2022 by the authors.

Cysteine peptidase inhibition: The way to impair SARS-CoV-2 infection and replication

Since its outbreak, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) caused one of the most severe pandemics in recent history and had enormous effects on the lives of millions of people worldwide. Peptidases, both viral and host, have been described as critical enzymes in mechanisms underlying SARS-CoV-2 infection and replication. Among host peptidases, the involvement in activation of viral glycoproteins and processing of the SARS-CoV spike protein has been described for endosomal/lysosomal cysteine peptidases cathepsins B and L, which therefore represent promising targets for development of effective drugs for treatment of COVID-19. To date, a large number of cathepsin B and L inhibitors have been identified and evaluated for treatment of various pathological processes. In this study, we have evaluated well-established known potent selective and reversible cathepsin B inhibitors for their potential to act against SARS-CoV-2. Cathepsin B inhibitors showed significant activity in preventing viral entry and replication of SARS-CoV-2. Next, we observed that antiviral activity of compounds was dependent on the cell type and correlated well with the intracellular amount of the targeted cathepsin. Taken together, we have demonstrated the important role of host cysteine peptidase cathepsin B during SARS-CoV-2 infection and identified its inhibitors as potential new therapeutic agents for treatment of SARS-CoV-2 infection.

Public trust and media influence on anxiety and depression levels among skilled workers during the COVID-19 outbreak in Serbia

Background/Aim. Along with the great impact of 2019 coronavirus disease (COVID-19) on physical health, social functioning, and economy, this public health emergency has significant impact on mental health of people as well. The aim of this study was to assess the impact of outbreak-related information and public trust in the health system and preventive measures during the COVID-19 outbreak in Serbia in 2020 on levels of anxiety and depression in education, army and healthcare professionals. Methods. An anonymous questionnaire was disseminated to skilled professionals working in fields of education, army, and healthcare. The questionnaire included the Beck Anxiety Inventory, Zung Self-Rating Depression Scale, as well as the section assessing the perceived disturbance by the outbreak-related information and the trust of participants in healthcare system and preventive measures proposed by the crisis team. Results. Out of 110 subjects enrolled in this study (mean age 35.25 ± 9.23 years), 59.1% were women. Among healthcare workers, the frequency of perceiving outbreak-related information available in public media as disturbing, as well as the average level of anxiety, were higher compared to the group of army professionals (p < 0.05). Women also perceived outbreak-related information available in public media as disturbing in a higher percentage compared to men (p < 0.01), and had higher levels of anxiety (p = 0.01) and depression (p < 0.05). The lack of public trust was associated with higher levels of depression, and the perception of outbreak-related information as disturbing with higher levels of both anxiety and depression. Conclusion. Significant perception of outbreak-related information as disturbing among healthcare workers, as well as the lack of trust in healthcare system and preventive measures proposed by the crisis team are important factors influencing the mental state. This finding has the guiding purpose for competent institutions to make efforts to increase public trust, as one of the important preventive measures, in order to preserve and improve the mental well-being of the population in outbreak conditions.