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The article presents the results of surveys conducted on three areas contaminated with organomineral and petroleum-containing waste. The selected research sites included a location affected by a fuel oil spill, a geoenvironment contaminated with petroleum products, and a territory of unauthorized disposal of distillery waste. Comprehensive engineering surveys were carried out on all sites, with some of them including engineering-geophysical surveys. The areas of the contaminated territories and the volume of waste were determined. Additionally, data evaluation was performed using the TPT-cloud software suite, which allowed for optimizing the scope of the conducted studies and accurately interpreting the research results to enhance the quality of the restoration works. The study justifies the methods for conducting restoration measures based on the proposed methodology for assessing the feasibility of using biological methods in land reclamation and waste disposal.

Infectious diseases are one of the most important problems of the modern world, for example, the periodic outbreaks of coronavirus infections caused by COVID-19, influenza, and many other respiratory diseases have significantly affected the economics of many countries. Hence, it is therefore important to minimize the economic damage, which includes both loss of work and treatment costs, quarantine costs, etc. Recent studies have presented many different models describing the dynamics of virus spread, which help to analyze the epidemic outbreaks. In the current work we focus on finding solutions that are robust to noise and take into account the dynamics of future changes in the process. We extend previous results by using a nonlinear model-predictive-control (MPC) controller to find effective controls. MPC is a computational mathematical method used in dynamically controlled systems with observations to find effective controls. [ABSTRACT FROM AUTHOR]

The analysis of global epidemics, such as SARS, MERS, and COVID-19, suggests a hierarchical structure of the epidemic process. The pandemic wave starts locally and accelerates through human-to-human interactions, eventually spreading globally after achieving an efficient and sustained transmission. In this paper, we propose a hierarchical model for the virus spread that divides the spreading process into three levels: a city, a region, and a country. We define the virus spread at each level using a modified susceptible–exposed–infected–recovery–dead (SEIRD) model, which assumes migration between levels. Our proposed controlled hierarchical epidemic model incorporates quarantine and vaccination as complementary optimal control strategies. We analyze the balance between the cost of the active virus spread and the implementation of appropriate quarantine measures. Furthermore, we differentiate the levels of the hierarchy by their contribution to the cost of controlling the epidemic. Finally, we present a series of numerical experiments to support the theoretical results obtained. [ABSTRACT FROM AUTHOR]

Objective: To describe the radiographic phenotype of axial spondyloarthritis (SpA) according to the presence of HLA-B27.Methods: An international collaboration compared the radiographic phenotype of axial SpA according to HLA-B27 status. Patients with ankylosing spondylitis (AS) and axial psoriatic arthritis (PsA) were collected. Radiographs were read centrally, blinded to clinical details. The symmetry of the sacroiliac joints and lumbar syndesmophytes and the morphology of syndesmophytes (typical marginal versus atypical chunky), together with the modified Stoke Ankylosing Spondylitis Spine Score and the Psoriatic Arthritis Spondylitis Radiographic Index, were recorded.Results: A total of 244 patients with PsA and 198 patients with AS were included. In PsA, 60 patients (25%) were HLA-B27 positive while in AS, 148 patients (75%) were HLA-B27 positive. Patients with HLA-B27 were younger and more often male and had a longer duration of disease. In multivariable logistic regression, HLA-B27 was significantly associated with syndesmophyte symmetry (odds ratio [OR] 3.02 [95% confidence interval (95% CI) 1.38, 6.61]) and marginal syndesmophytes (OR 1.97 [95% CI 1.16, 3.36]) but not with sacroiliac symmetry. Mean radiographic scores were higher for patients with HLA-B27.Conclusion: Patients with axial SpA who are positive for HLA-B27 have more severe radiographic damage, more marginal syndesmophytes, and more frequent syndesmophyte symmetry compared to patients who are negative for HLA-B27. [ABSTRACT FROM AUTHOR]

In the current study, we define a hierarchical epidemic model that helps to describe the propagation of a pathogen in a clustered human population. The estimation of a novel coronavirus spreading worldwide leads to the idea of the hierarchical structure of the epidemic process. Thus, the propagation process is divided into three possible levels: a city, a country, and a worldwide. On each level, the pathogen propagation process is based on the susceptible-exposed-infected-recovered (SEIR) model. We thus formulate a modified transmission model of infected individuals between levels. The control of the pathogen's spread can be seen as an optimal control problem. A trade-off exists between the cost of active virus propagation and the design of appropriate quarantine measures. Each level of the hierarchy is defined by its network. A series of numerical experiments was conducted to corroborate the obtained results. [ABSTRACT FROM AUTHOR]

Different strains of influenza viruses spread in human populations during every epidemic season. As the size of an infected population increases, the virus can mutate itself and grow in strength. The traditional epidemic SIR model does not capture virus mutations and, hence, the model is not sufficient to study epidemics where the virus mutates at the same time as it spreads. In this work, we establish a novel framework to study the epidemic process with mutations of influenza viruses, which couples the SIR model with replicator dynamics used for describing virus mutations. We formulated an optimal control problem to study the optimal strategies for medical treatment and quarantine decisions. We obtained structural results for the optimal strategies and used numerical examples to corroborate our results. [ABSTRACT FROM AUTHOR]