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Increased awareness of nature preservation has encouraged the introduction of the green analytical chemistry (GAC) practice concepts concerning several important aspects, including sustainable development, environmental impact, and minimum waste. The aim of this research was to contribute to the implementation of this approach for the pharmaceutical industry while retaining the crucial aspects and strict requirements of quality control of medicines. Therefore, an ethanolbased, green and robust high-performance liquid chromatography (HPLC) method for the determination of related substances of amlodipine (AML) in film-coated tablets was developed and optimized using the Design of Experiments (DoE). The chromatographic separation was performed on an RP-select B column (250 x 4.0 mm, 5 mm), using a mixture of 0.04 M sodium dihydrogen phosphate monohydrate (pH 4.0) and ethanol (60:40 % v/v) as a mobile phase. The optimized conditions provided the separation of two specified impurities (impurity D and impurity F). The selectivity of the method was confirmed using forced degradation studies. The Analytical Eco-scale approach and AGREE metrics confirmed that the method conforms to the GAC principles. The validated method was successfully applied for the determination of related substances in three samples from the market, demonstrating the applicability of the method in routine analysis.

This review paper is an homage to Arvid Palmgren’s pioneering paper on rolling bearing service life to highlight its relevance a century later. It follows the evolution of bearing service life theory from Palmgren’s fundamental research to the contemporary international standard ISO 281. Palmgren’s theory, based on the previously published papers of Stribeck and Hertz, laid the basis for the later development of bearing service life assessment methodology. Based on the Weibull theory of probability of damage, Lundberg and Palmgren introduced stochastic elements to explain the effect of reliability on bearing service life prediction. Harris and Ioannides, who made a significant contribution to the revision of the international standard on rolling bearing load rating and rating life are mentioned as well. Zaretsky’s critical analysis also was not neglected in this review, due to a different approach respecting the original influence of material properties and bearing performances. Despite standardization, ongoing research by leading advanced bearing industries and academic institutions continues to refine methodologies for service life assessment. Through a comprehensive review and analysis, this paper offers insight into the current state of bearing service life theory, highlighting the collaborative efforts bringing progress in this field.

IntroductionDespite several studies assessing job demands and burnout in countries from the Southeast European (SEE) region, there is still a lack of data about the psychological impact of the pandemic on health workers (HWs).AimsThe present study aimed to demonstrate and compare levels of burnout dimensions in HWs from SEE countries and to reveal the burnout–job demands/resources relationships in these workers during the pandemic.Materials and methodsDuring the autumn of 2020, this online multicentric cross-sectional survey studied a large group (N = 4.621) of HWs working in SEE countries. The Maslach Burnout Inventory was used for the measurement of burnout dimensions. We analyzed the job demands by using the Hospital Experience Scale. Remuneration and relationships with superiors were measured using the Questionnaire sur les Ressources et Contraintes Professionnelles (English version).ResultsA series of ANOVA comparisons of means revealed the countries in which respondents showed higher mean values of emotional exhaustion (Bosnia and Herzegovina, Bulgaria, Croatia, Moldova, Montenegro, and North Macedonia) and the countries in which respondents showed lower mean values of this burnout dimension (Israel and Romania) (Welch F = 17.98, p

Increasing population, expansion of urban areas and rapid urbanization are the main causes of losing green spaces, which results in many environmental problems and threatens the quality of urban life. Urban green spaces are of great importance and urban planning issues nowadays gain increasing popularity. It is realized that biological methodologies need to be used in urban planning, otherwise the quality of life will be more threatened. In order to discover the meaning and importance of green corridors in urban areas, a literature review was undertaken. Boulevards, as green corridors, are very important linear parts in the structures of dense modern cities. If planned and designed properly, they mitigate the negative effects of densely built urban environment. Green corridors provide numerous environmental benefits, they are an essential factor of sustainability and have a significant impact on biodiversity. Green corridors also provide social benefits, by enhancing well-being through contact with nature. They decrease health problems and improve the quality of life. The importance of urban green corridors was observed and presented on the example of Blvd. Bosnia and Herzegovina and Blvd. Hristijan Todorovski Karposh, which form an important ecological network in the northern part of Skopje, North Macedonia. The emphasis is on planning, designing and improving green corridors in urban areas like Skopje. Although these two boulevards are well designed as green corridors, with preserved old line greenery, planted with many different plant species (trees, shrubs, perennials), covered by grass, with bicycle and pedestrian paths, there is still potential for improvement. Linear parks on both sides of the new part of the Blvd. Hristijan Todorovski Karposh would be a great idea.

We investigated acute effects of the Na+,K+‐ATPase (NKA) inhibitor, digoxin, on muscle NKA content and isoforms, arterial plasma [K+] ([K+]a) and fatigue with intense exercise. In a randomised, crossover, double‐blind design, 10 healthy adults ingested 0.50 mg digoxin (DIG) or placebo (CON) 60 min before cycling for 1 min at 60% V̇O2peak${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ then at 95% V̇O2peak${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ until fatigue. Pre‐ and post‐exercise muscle biopsies were analysed for [3H]‐ouabain binding site content without (OB‐Fab) and after incubation in digoxin antibody (OB+Fab) and NKA α1‐2 and β1‐2 isoform proteins. In DIG, pre‐exercise serum [digoxin] reached 3.36 (0.80) nM [mean (SD)] and muscle NKA–digoxin occupancy was 8.2%. Muscle OB‐Fab did not differ between trials, whereas OB+Fab was higher in DIG than CON (8.1%, treatment main effect, P = 0.001), whilst muscle NKA α1‐2 and β1‐2 abundances were unchanged by digoxin. Fatigue occurred earlier in DIG than CON [−7.7%, 2.90 (0.77) vs. 3.14 (0.86) min, respectively; P = 0.037]. [K+]a increased during exercise until 1 min post‐exercise (P = 0.001), and fell below baseline at 3–10 (P = 0.001) and 20 min post‐exercise (P = 0.022, time main effect). In DIG, [K+]a (P = 0.035, treatment effect) and [K+]a rise pre‐fatigue were greater [1.64 (0.73) vs. 1.55 (0.73), P = 0.016], with lesser post‐exercise [K+]a decline than CON [−2.55 (0.71) vs. −2.74 (0.62) mM, respectively, P = 0.003]. Preserved muscle OB‐Fab with digoxin, yet increased OB+Fab with unchanged NKA isoforms, suggests a rapid regulatory assembly of existing NKA α and β subunits exists to preserve muscle NKA capacity. Nonetheless, functional protection against digoxin was incomplete, with earlier fatigue and perturbed [K+]a with exercise. Key points: Intense exercise causes marked potassium (K+) shifts out of contracting muscle cells, which may contribute to muscle fatigue.Muscle and systemic K+ perturbations with exercise are largely regulated by increased activity of Na+,K+‐ATPase in muscle, which can be specifically inhibited by the cardiac glycoside, digoxin.We found that acute oral digoxin in healthy adults reduced time to fatigue during intense exercise, elevated the rise in arterial plasma K+ concentration during exercise and slowed K+ concentration decline post‐exercise.Muscle functional Na+,K+‐ATPase content was not reduced by acute digoxin, despite an 8.2% digoxin occupancy, and was unchanged at fatigue. Muscle Na+,K+‐ATPase isoform protein abundances were unchanged by digoxin or fatigue. These suggest possible rapid assembly of existing subunits into functional pumps.Thus, acute digoxin impaired performance and exacerbated plasma K+ disturbances with intense, fatiguing exercise in healthy participants. These occurred despite the preservation of functional Na+,K+‐ATPase in muscle. [ABSTRACT FROM AUTHOR]

Introduction: Cheiloscopy is defined as the study of the sulci labiorum, known as "lip prints". Aim of the study: The aim of this study was to determine the morphological characteristics of the lip grooves in the three dominant nationalities in the Republic of North Macedonia (Macedonians, Albanians, Roma) and to compare the obtained results with the morphological characteristics of the lip grooves in three other populations from different geographical regions. Material and methods: In this research, we included 150 examinees aged 25-50 years and divided them into three groups: Macedonians (50), Albanians (50) and Roma (50). The lip prints were taken using microscopic slides and detected using the dactyloscopic powder and brush method. We used the Suzuki and Tsuchihashi classification to typify the lip prints. Results: The most common type of lip grooves in the population of the Republic of North Macedonia was the type II grooves. There was no significant difference in the presence of different types of lip grooves in the four quadrants between males and females, nor between Macedonians, Albanians and Roma. The comparative analysis showed that populations from different geographical areas had different anthropological and morphological characteristics of the lip grooves. Conclusion: Type II lip grooves are the most common in the population of the Republic of North Macedonia and there is no statistically significant difference between the prevalence of different types of lip grooves in the three nationalities in this study. Considering the large number of factors that can affect the quality of the lip print, we recommend that a swab should always be taken before collecting the lip print in order to attempt to extract DNA material from the found trace.

Wine is not just a product of modern times. Wine, one of the oldest drinks in the world, was sold and inherited by ancient civilizations. Its importance is indicated by the regulation of wine in the Codes of ancient Mesopotamia and Roman law. Today, this agri-food product is sold on both the domestic and foreign markets, and it is indisputable that the production and sale of this product must be legally regulated. The authors of this paper, by analyzing the legal provisions of Roman law, the Law on Wine and the Criminal Code of Republic of Serbia, point out the importance of the existence and expansion of legal provisions related to wine and its producers and precise criminal law provisions in case of sale of wine produced contrary to legal regulations and contrary to the health of people who consumed the same. The stated purpose of the paper, in order to draw a conclusion about the importance of specifying legal provisions, was achieved by presenting the historical and positive legal regulation, using the historical method and comparative analysis.

Our objective was to investigate the inflammatory and oxidative stress markers in patients with moderate and severe form of COVID-19. In addition, we show the correlation between changes in lymphocyte subsets and markers of oxidative stress as a tool for patient classification. IL-6 and VEGF were analysed by utilizing a High Sensitivity Evidence Investigator™ Biochip Array technology. The total antioxidant capacity (PAT) and the free radical concentrations (d-ROM) were measured in serum utilizing analytical photometric system FRAS5. Peripheral blood was used to determine CD45 + mononuclear, B, T, and NK cells using a multi-parameter flow cytometric immunophenotypic test. Statistically significant differences in IL-6 and VEGF levels were observed between the two patient groups. Decreased values of the absolute number of lymphocytes and their CD4 + and CD8 + positive T cells, NK cells, and CD8 were obtained. In the moderate group, good correlations were found between IL-6 and VEGF and NK cells (r = 0.6973, p

Background. Clinical evidence suggests increased oxidative stress in COVID-19 patients and this worsened redox status could potentially contribute to the progression of the disease.

Background. The aim of this study was to evaluate the ability of severity scoring systems to predict 30-day mortality in patients with severe community-acquired pneumonia.

During the last few decades, the requirements for modern machine elements in terms of size reduction, increasing the energy efficiency, and a higher load capacity of standard and non-standard gears have been very prevalent issues. Within these demands, the main goals are the optimization of the gears’ tooth profiles, as well as the investigation of new tooth profile designs. The presented design idea is based on the optimal solutions inspired by nature. Special attention is paid to the new design of the tooth root zones of spur gears in order to decrease the stress concentration values and increase the tooth root fatigue resistance. The finite element method is used for stress and strain state calculations, and the particular gear pair is modeled and optimized for these purposes. For tooth root strength analysis, the estimations are based on the theory of critical distances and the stress gradients obtained through finite element analysis. The obtained stress gradients have shown important improvements in the stress distribution in the transition zone optimized by biomimetics. An analysis of the material variation influence is also performed. Based on the investigations of a particular gear pair, a significant stress reduction of about 7% for steel gears and about 10.3% for cast iron gears is obtained for tooth roots optimized by bio-inspired design.

In this paper, a comparison between six finite element models of a representative wing structural component performed in the context of Optimised Design for Inspection (ODIN) project of the European Cooperation in Science and Technology (COST) is presented. Six partners from six different countries involved in the project received the drawing of the structure, the material properties, the loading and boundary conditions. Each partner, based on their background and experience in numerical analyses, developed a finite element model with different levels of details and accuracy and performed a blind prediction of the structural behaviour of the wing component. The numerical results are presented and compared with the experimental test data conducted at Cardiff University.

The paper considers dimensional synthesis of a path generator four-bar linkage by applying the modified Differential Evolution (DE) algorithm. During the search of the space, the DE algorithm may skip the right solution and lead to premature convergence. If the step is reduced, the search space is reduced as well, so that convergence becomes slower. Search efficiency may be achieved by including Lévy Flight in the DE algorithm. Namely, when the DE algorithm identifies the space of best solution, then a Levý Flight step is used for local search in that region, which significantly increases the exploitation capability and allows obtaining a very efficient solution of the optimization problem. The algorithm was tested with three examples of dimensional synthesis of a path generator four-bar linkage. The proposed algorithm can be very efficiently applied to solving very complex optimization problems. [ABSTRACT FROM AUTHOR]

Background COVID-19 is characterized by the presence of oxidative stress. Vitamin D status has been reviewed as one of the factors that may affect disease severity. The aim of this study was to assess the relationship between serum vitamin D levels, oxidative stress markers and disease severity in hospitalized COVID-19 patients. Methods Vitamin D levels were measured in 33 patients with COVID-19. The total antioxidant power and plasma peroxides were determined in serum. Results Severe COVID-19 patients have lower vitamin D levels (18.39 ± 2.29 ng/mL vs. 28.47 ± 3.05 ng/mL, p

The repair of structural elements for the prestressing of reinforced concrete is necessary when existing prestressing wires are damaged or after a certain period of time. The objective of this paper is to describe the methodology for the life assessment of corroded prestressing wires, sampled from prestressed concrete elements after a few decades of use. The aim of the presented research was to determine the real properties of corroded wire in terms of the evaluation of remaining load capacity using the Theory of Critical Distances (TCD). The methodology also includes spatial 3D characterization of corroded surfaces, determination of mechanical properties, and Finite Element Analysis (FEA) of a model of wire with corrosion pits. The final goal of the presented methodology is to enable more efficient evaluation of repair range and options for the elements of mechanical prestressing systems within various structures. The results and conclusions indicate that the developed methodology, based on the interdisciplinary approach and implementation of state-of-the-art methods, has a high applicability potential for both static and fatigue fracture prediction in the case of prestressed wires. The proposed method has a huge potential for simple and fast prediction of the life assessment of engineering structures, particularly for damaged elements with arbitrary geometry features.

Introduction: COVID-19 can be worsened by hyper-production of cytokines accompanied by increased level of oxidative stress. The aim of this study was to investigate the correlation between a set of cytokines and the markers of the oxidative stress. Methods: The levels of cytokines IL-2, IL-4, IL-6, IL8, IL-10, VEGF, IFN-γ, TNF-α, IL-1α, MCP-1 and EGF were determined by using High Sensitivity Evidence Investigator™ Biochip Array technology. The oxidative stress parameters (d-ROM, PAT, OS index) were measured in serum on FRAS5 analytical photometric system. Results: IL-6, IL-8, IL-10, VEGF, MCP-1 and EGF were significantly higher (p Conclusion: The oxidative stress markers show good correlation with the tested cytokines which can be measured at the beginning of the disease in a primary care setting to predict the course of COVID-19.

Introduction: COVID-19 can be worsened by hyper-production of cytokines accompanied by increased level of oxidative stress. The aim of this study was to investigate the correlation between a set of cytokines and the markers of the oxidative stress. Methods: The levels of cytokines IL-2, IL-4, IL-6, IL8, IL-10, VEGF, IFN-γ, TNF-α, IL-1α, MCP-1 and EGF were determined by using High Sensitivity Evidence Investigator™ Biochip Array technology. The oxidative stress parameters (d-ROM, PAT, OS index) were measured in serum on FRAS5 analytical photometric system. Results: IL-6, IL-8, IL-10, VEGF, MCP-1 and EGF were significantly higher (p Conclusion: The oxidative stress markers show good correlation with the tested cytokines which can be measured at the beginning of the disease in a primary care setting to predict the course of COVID-19.

Neoclassical economic theories form the basis of modern economics, along with the principles of Keynesian economics. As part of economic theory, the main direction that reveals the functioning mechanism of a market economy is the neoclassical direction. In this regard, identifying the peculiarities of the relationship between the subject and method of the neoclassical direction is an urgent task, since it will make it possible to more clearly define the place of the neoclassical direction in modern economic thought, identify the theoretical basis and applicability of practical recommendations of neoclassics, in particular, more clearly define its capabilities as a theoretical basis for the formation market economy in different countries. In this article, the authors analyze the difference between neoclassical macroeconomics and microeconomics. It is shown that the microeconomic aspects of neoclassical theory have much greater theoretical and applied significance than neoclassical macroeconomics. They largely reflect real economic processes and determine the economic behavior of economic entities. The work examines, in a microeconomic aspect, the theoretical approaches of the main representatives of neoclassical theory, such as A. Marshall, L. von Mises and other representatives, to the analysis of economic processes. The authors note the importance of limit analysis, which has not only theoretical but also practical significance. The work also examines the approaches of representatives of neoclassical theory to assessing the value and price of goods and economic resources. In the real economy, markets of imperfect competition predominate, which are characterized by their own characteristics that influence the economic behavior of firms in commodity and resource markets, as evidenced by the use of marginal analysis to substantiate the position of the authors. The article assesses the views of representatives of the neoclassical school on the differences between market and planned economies. Their approach to the process of economic monopolization is characterized. [ABSTRACT FROM AUTHOR]

In this paper, the gear contact evaluation models developed using various methods have been discussed. The new experimental and numerical methods have been presented. The research papers are classified into frictionless and frictional contact stress analysis and subdivided into experimental and finite element models. This paper will provide researchers with various information and huge literature data on the described subject. It serves as the rapid retrieval of data related to gear contact stress evaluation. Furthermore, a comprehensive discussion focusing on the customized experimental test rig (Gear Dynamic Stress Test Rig) has been done. Also, the finite element (FE) results showing the variation of contact stresses with and without friction, along the contact path has been shown. The FE results revealed that the contacting stresses between the gears increased significantly for different parallel axis gear, for a given coefficient of friction rise considered in the study.

Barbara Cvenkel,1,2 Makedonka Atanasovska Velkovska11Department of Ophthalmology, University Medical Centre Ljubljana, Ljubljana, Slovenia; 2Medical Faculty, University of Ljubljana, Ljubljana, SloveniaPurpose: To determine the value of self-monitoring of diurnal intraocular pressure (IOP) by Icare Home rebound tonometer in patients with glaucoma and ocular hypertension.Methods: Patients with open-angle glaucoma or ocular hypertension, controlled IOP at office visits, and at least 3 years of follow-up in the glaucoma clinic were included. Progression of glaucoma was based on medical records and defined by documented structural and/or visual field change. Patients were trained to correctly perform self-tonometry and instructed to measure diurnal IOP in a home setting for 3 days. IOP characteristics (mean, peak IOP, fluctuation of IOP as range, and SD of IOP) were documented and compared between the progressive and stable eyes.Results: Ninety-four patients (50 females) with a mean (SD) age of 57.1 (14.7) years were included. Among the 94 eyes from 94 subjects, 72 (76.6%) eyes had primary open-angle glaucoma, ten (10.6%) had pigmentary glaucoma, four (4.3%) had exfoliative glaucoma, and eight (8.5%) eyes had ocular hypertension. Thirty-six eyes showed progression and 58 eyes were stable. Patients with progression were older than those with stable disease (mean (SD) 65.8 (8.4) years vs 51.7 (15.3) years, P

Researchers in the field of fracture mechanics, predominantly developing appropriate solution algorithms for problems of solid bodies with cracks. Problems in mechanics generally, related with fracture and fatigue for solid bodies with various geometries of sharp notches, are studied to a much lesser extent. This situation can be explained by analytical difficulties arising in solving problems of elasticity theory for bodies with rounded notches. To solve problems of such class, starting from data on stress concentration in the rounded notch tip with a significant radius of curvature, simplified solutions with are therefore of great importance. Recent years, due to constant rise of computing power and development of numerical methods, re-evaluation of stress concentration factors from a viewpoint of theory of elasticity is present. This is mainly as a feedback from industry, which have requirements toward mega and nanostructures. Corrosion represents an important limitation to the safe and reliable use of many alloys in various industries. Pitting corrosion is a form of serious damage on metals surface such as high-strength aluminum alloys and stainless steel, which are susceptible to pitting when exposed to a corrosive attack in aggressive environments. This is particularly valid for dynamic loaded structures. The basic idea behind this paper is finding links between different scientific and engineering disciplines, which will enable useful level of applicability of existing knowledge. The subject of this paper is application of new method of determine length scale parameter for estimating the mechanistic aspect of corrosion pit under uniaxial/multiaxial high-cycle fatigue loading