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Air classification is widely used in industry for fractionation of crushed materials. Simplicity and high efficiency at low energy costs are distinguished by air classifiers with an inclined louver grille. The relevance of the work is conditioned upon the fact that it conducted an experimental and theoretical study of these devices on a model material – quartzite, which retains its density regardless of size. Through an experimental and theoretical study on a model material, quartzite, this work aims to investigate air classifiers with an inclined louver grille and propose a mathematical model that can reduce the amount of preliminary work required for calculating industrial classifiers. In the process of mathematical modelling, two tasks were solved: calculating the velocity field of two-dimensional vortex-free air flows inside the classifier and the subsequent study of particle motion in these fields. To set the correct boundary conditions of the problem, a thermomagnetometry was made and experimental studies of air velocities at the defining points of the classifier were carried out. A model of the distribution of extracted particles along the height of the classifier is suggested. A comparison of theoretical calculations with experimental data at different speeds and consumption concentrations showed satisfactory agreement. This study provides valuable insights into the separation properties of air classifiers with an inclined louver grille, specifically on a model material, quartzite. By conducting both experimental and theoretical studies, the authors were able to develop a mathematical model that accurately predicts air classification indicators for various materials. The results of this study have significant prospects in the industry, as it can potentially reduce the time and cost required for conducting preliminary laboratory studies on small copies of devices for specific types of raw materials.

Since the COVID-19 pandemic, improving indoor air quality (IAQ) has become vital for the public as COVID-19 and other infectious diseases can transmit via inhalable aerosols. Air cleaning devices with filtration and targeted pollutant treatment capabilities can help improve IAQ. However, only a few filtration/UV devices have been formally tested for their effectiveness, and little data is publicly available and UV doses comparable. In this research, we upgraded a particulate matter (PM) air filtration prototype by adding UV-C (germicidal) light. We developed realistic UV dose metrics for fast-moving air and selected performance scenarios to quantify the mitigation effect on viable airborne bacteria and PM. The targeted PM included total suspended particulate (TSP) and a coarse-to-fine range sized at PM10, PM4, PM2.5, and PM1. The PM and viable airborne bacteria concentrations were compared between the inlet and outlet of the prototype at 0.5 and 1.0 m3/s (low and high) air flow modes. The upgraded prototype inactivated nearly 100% of viable airborne bacteria and removed up to 97% of TSP, 91% of PM10, 87% of PM4, 87% of PM2.5, and 88% of PM1. The performance in the low flow rate mode was generally better than in the high flow rate mode. The combination of filtration and UV-C treatment provided ‘double-barrier’ assurance for air purification and lowered the risk of spreading infectious micro-organisms.

Rough processing of iron ore employs dry methods which means that equipment is tuned to process large particles, but fine magnetic material less than a few tenths of a millimeter in size is not separated as efficiently. The relevance of this study is determined by the fact that dry beneficiation waste contains recoverable iron-bearing magnetite of commercial value. Commercial justification of waste beneficiation is associated with mining and grinding costs that are already included in the prime cost of the commercial concentrate. The future of tailings retreatment prospects depends on technology and efficiency of the employed equipment, the development of which is the subject of this paper. At first stage, fine iron is recovered by air sizing, with pitched curtain air classifiers embedding simple design and high performance. Powder materials were magnetically separated by a manufactured drum-type separator in which, to increase the separation efficiency, the process was performed at increased drum rotation speeds using Nd-Fe-B magnets and a drum made of electrically non-conductive materials. The separator performance was determined for various rotation speeds of the drum. Research has proven that a multi-stage magnetic separation with a consequent increase in drum rpm is reasonable. A new cascade separator was manufactured and tested for this purpose. It is shown that iron-containing ore tailings beneficiation is optimal without any additional grinding.

The work deals with the mathematical modeling of traffic phenomena. The submitted model is based on a prospective analogy of some described phenomena with particle sedimentation. Both the qualitative analysis of the model and the numerical experiment is carried out. Qualitative results of the research have been compared with the known data of supervision of the traffic on city highways. As a result, the main control parameters which can use for optimal traffic management are highlighted and justified.

Background/objectiveRefugees and migrants to the World Health Organization (WHO) European Region are disproportionately affected by infections, including tuberculosis (TB), human immunodeficiency virus (HIV) and hepatitis B and C (HBV/HCV) compared with the host population. There are inequities in the accessibility and quality of health services available to refugees and migrants in the Region. This has consequences for health outcomes and will ultimately impact the ability to meet Regional infection elimination targets.MethodsWe reviewed academic and grey literature to identify national policies and guidelines for TB/HIV/HBV/HCV specific to refugees and migrants in the Member States of the WHO European Region and to identify: (i) evidence informing policy and (ii) barriers and facilitators to policy implementation.ResultsRelatively few primary national policy/guideline documents were identified which related to refugees and migrants and TB [14 of 53 Member States (26%), HIV (n = 15, 28%) and HBV/HCV (n = 3, 6%)], which often did not align with the WHO recommendations, and for some countries, violated refugees' and migrants’ human rights. We found extreme heterogeneity in the implementation of the WHO- and European Centre for Disease Prevention and Control (ECDC)-advocated policies and recommendations on the prevention, diagnosis, treatment and care of TB/HIV/HBV/HCV infection among migrants across the Member States of the WHO European Region.There is great heterogeneity in implementation of WHO- and ECDC-advocated policies on the prevention, diagnosis, treatment and care of TB/HIV/HBV/HCV infection in refugees and migrants across the Member States in the Region.ConclusionMore transparent and accessible reporting of national policies and guidelines are required, together with the evidence base upon which these policy decisions are based. Political engagement is essential to drive the changes in national legislation to ensure equitable and universal access to the diagnosis and care for infectious diseases.

INTRODUCTION: Since 2015 (updated in 2019), the WHO has recommended to include the commercial lateral flow urine lipoarabinomannan TB test (LF-LAM), AlereLAM, in the diagnostic toolkit for severely ill people living with HIV.METHODS: To assess the current use and barriers to the implementation of the test, we conducted an electronic survey among national focal points and managers of TB and HIV programmes in the 53 Member States of the WHO European Region and a European network of clinicians working in TB and HIV medicine.RESULTS: In all, 45 individual responses (37 countries) were received from programme managers and focal points and 17 responses (14 countries) from clinicians. Only eight countries reported adopting LF-LAM policies, with only four currently using the AlereLAM (Armenia, Belarus, Ukraine and Uzbekistan). The most commonly reported barriers to implementing the test were the small number of eligible patients (with HIV-TB co-infections), the test not being included in the TB or HIV programme´s mandate and lack of budget allocation.CONCLUSION: Consistent with findings from high TB burden countries in Africa and Asia, the survey demonstrated that uptake of AlereLAM is almost non-existent. Addressing the identified barriers and the intrinsic limitations of the test could help to increase the use of the test.

The World Health Organization (WHO) recently revised its guidelines for rapid diagnosis of drug-resistant tuberculosis (TB). This study aimed to investigate if TB reference diagnostic services are prepared to support these revisions. An online survey was performed among 44 TB National Reference Laboratories (NRLs) in the WHO European Region. Questions addressed the use of WHO-recommended molecular techniques for the diagnosis of drug-resistant TB, the techniques applied to investigate antimicrobial resistance, and questions on quality assurance. Among 35 of 44 (80%) participating NRLs, 29 of 35 (83%) reported using the GeneXpert platform as the initial test to detect Mycobacterium tuberculosis complex and rifampicin resistance. Five laboratories reported using another WHO-recommended, moderate-complexity, automated nucleic acid amplification test for detection of Mycobacterium tuberculosis complex and resistance to rifampicin and isoniazid. Most (32 of 35; 91%) NRLs reported the capacity to test second-line drugs that have been in clinical use for many years (fluoroquinolones, linezolid, and injectable agents). Only 23 of 35 (66%) and 21 of 35 (60%) NRLs reported the capacity to test bedaquiline and clofazimine. Further efforts will be needed to improve the availability of quality-controlled testing against WHO Group A and Group B drugs. Earlier considerations on the scale-up of diagnostic capacities should be enforced as part of future approval processes for new antimycobacterial agents.

Technical advances in diagnostic techniques have permitted the possibility of multi-disease-based approaches for diagnosis and treatment monitoring of several infectious diseases, including tuberculosis (TB), human immunodeficiency virus (HIV), viral hepatitis and sexually transmitted infections (STI). However, in many countries, diagnosis and monitoring, as well as disease response programs, still operate as vertical systems, potentially causing delay in diagnosis and burden to patients and preventing the optimal use of available resources. With countries facing both human and financial resource constraints, during the COVID-19 pandemic even more than before, it is important that available resources are used as efficiently as possible, potential synergies are leveraged to maximise benefit for patients, continued provision of essential health services is ensured. For the infectious diseases, TB, HIV, hepatitis C (HCV) and STI, sharing devices and integrated services starting with rapid, quality-assured, and complete diagnostic services is beneficial for the continued development of adequate, efficient and effective treatment strategies. Here we explore the current and future potential (as well as some concerns), importance, implications and necessary implementation steps for the use of platforms for multi-disease testing for TB, HIV, HCV, STI and potentially other infectious diseases, including emerging pathogens, using the example of the COVID-19 pandemic. Daniel Simões was the recipient of PhD grant PD/BD/128008/2016 from Fundação para a Ciência e Tecnologia (FCT), co-funded by the “Programa Operacional Capital Humano/Fundo Social Europeu” (POCH/FSE). The funder did not have any role in manuscript preparation, revision or submission. Sí

The relevance of the paper is that dry magnetic separation (DMS) is the main beneficiation method of magnetite ores. The lack of efficient industrial-grade machines and apparatus for separating fine-grained magnetite ores means that DMS is used mainly as a pre-concentration operation for fairly large classes. The aim of the research is to study the possibility of using a new magnetic separator model in the process of dry beneficiation of magnetite ore from the Bapy deposit. This paper presents theoretical and experimental studies of a new model of a magnetic separator. The mathematical modeling of the magnetic separation process of the device was carried out to evaluate the parameters in accordance with which a laboratory separator was subsequently manufactured. For the experimental study of the properties of this magnetic system, a laboratory magnetic separator was built. The possibility of using a new magnetic separator in the process of dry beneficiation of magnetite ore from the Bapy deposit was investigated. The industrial scheme being implemented consists in ore crushing and two stage dressing on dry drum magnetic separators. The study of beneficiation indicators of the magnetic separator was carried out using iron ore of the Bapy deposit, which is mono-mineral magnetite. For the study, mixtures of the minus 0.1 mm class were selected with the iron content α = 50% and α = 40%. As a result of the research, beneficiation indicators were obtained on a laboratory scale. Therefore, the improvement of the beneficiation scheme is reduced to the isolation of a small product and its subsequent beneficiation using a new model of magnetic separator. Thus, the presented magnetic separator is suitable for dry processing of crushed magnetite ore.