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The flow and forced convection heat transfer properties of triply periodic minimal surface (TPMS) lattices were investigated both experimentally and numerically. The TPMS structures consist of periodically arranged Gyroid (G) unit cells of 81 % porosity and different unit cell sizes (2–4 mm). This is the first study to evaluate the effect of cell diameter on pressure drop and heat transfer characteristics of solid-gyroid structures prepared by selective laser melting (SLM) technique. Moreover, the range of pore-based Reynolds number covered the laminar and turbulent regimes (Rep=11–1700). The results shown that larger cell diameter provides higher heat transfer coefficients and unit pressure drop. An increase of cell diameter from 2 mm to 4 mm can enhance heat transfer coefficient and unit pressure drop of 39 % and 85 %, respectively. New correlations for flow resistance and heat transfer of solid-gyroid structures were developed. It was confirmed that TPMS lattices can be an alternative to conventional catalytic supports, because they provide comparable thermal efficiency index as foam and packed bed.

The growing number of acute drug abuse overdoses demands the development of innovative detoxification strategies for emergency purposes. In this study, an innovative approach for the application of porous Zr-based metal–organic frameworks for the treatment of acute overdoses of popular drugs of abuse including amphetamine, methamphetamine, cocaine, and MDMA is presented. A comprehensive approach determining the efficacy and the kinetics of drug removal, considering dosage, adsorption time, and adsorption mechanisms, was tested and corroborated with density functional theory (DFT) modeling. The experimental results showed high removal efficiency reaching up to 90% in the case of the application of the NU-1000 metal–organic framework. The difference Raman spectroscopy method presented in this study corroborated with DFT-based vibrational analysis allows the detection of drug adsorbed in the MOF framework even with as low a concentration as 5 mg/g. Additionally, the drug adsorption mechanisms were modeled with DFT, showing the π–π stacking in a vast majority of considered cases. The performance and influence on the living organisms were evaluated throughout the in vitroand in vivoexperiments, indicating that Zr-based MOFs could serve as efficient, organic, safe drug adsorbents.

In this study, we present a complementary approach for obtaining an effective drug, based on acriflavine (ACF) and zirconium-based metal–organic frameworks (MOFs), against SARS-CoV-2. The experimental results showed that acriflavine inhibits the interaction between viral receptor-binding domain (RBD) of spike protein and angiotensin converting enzyme-2 (ACE2) host receptor driving viral cell entry. The prepared ACF@MOF composites exhibited low (MOF-808 and UiO-66) and high (UiO-67 and NU-1000) ACF loadings. The drug release profiles from prepared composites showed different release kinetics depending on the local pore environment. The long-term ACF release with the effective antiviral ACF concentration was observed for all studied ACF@MOF composites. The density functional theory (DFT) calculations allowed us to determine that π–π stacking together with electrostatic interaction plays an important role in acriflavine adsorption and release from ACF@MOF composites. The molecular docking results have shown that acriflavine interacts with several possible binding sites within the RBD and binding site at the RBD/ACE2 interface. The cytotoxicity and ecotoxicity results have confirmed that the prepared ACF@MOF composites may be considered potentially safe for living organisms. The complementary experimental and theoretical results presented in this study have confirmed that the ACF@MOF composites may be considered a potential candidate for the COVID-19 treatment, which makes them good candidates for clinical trials.

AbstractEndovascular aneurysm repair (EVAR) has become one of the most important treatments for aortic abdominal aneurysm. This method has some possible complications, including a type II endoleak (T2E). When coexisting with arteriovenous fistulas (AVF), T2E can lead to serious hemodynamic consequences and organ failure. This report describes the management of a patient with T2E coexisting with AVF following an EVAR and re-EVAR procedure. Although T2E itself may be treated with a conservative approach in some cases, in the presented patient an operative approach was necessary because of coexisting AVF. In addition, due to unusual hemodynamic conditions created by concomitant ACF and T2E, fistula closure was obtained as a result of transarterial inferior mesenteric artery embolization. Post-EVAR imaging, including ultrasound and computed tomography angiography, has proven to be essential when caring for these patients.

The paper presents a method for grouping forest districts that are characterised by similar natural and forest conditions and the results of standardisation of wood extraction costs for forest districts and regional directorates of the State Forests. The adopted standard costs referred to the costs which determine the reasonable level of costs necessary to perform a specific management task in the given natural, forest and economic conditions of forest districts. Forest districts were grouped based on the forest habitat types and the land diversity index (Wtri), which were determined with statistical methods to be the factors that shape wood extraction costs. In order to determine the standard unit costs of wood extraction, source materials for the year 2017 have been used, which had been obtained from the State Forests Information System for all forest districts in the country. The method of standardising wood extraction unit costs on the basis of forest district groups with similar natural and forest conditions was reduced in 2017 to the designation of eight uniform forest district groups in terms of forest habitat type structure and Wtriindex. Standard unit costs of wood extraction, determined on the basis of the methodology presented in the paper, should be used in the State Forests’ financial system.

The removal of uremic toxins from patients with acute kidney injury is a key issue in improving the quality of life for people requiring peritoneal dialysis. The currently utilized method for the removal of uremic toxins from the human organism is hemodialysis, performed on semipermeable membranes where the uremic toxins, along with small molecules, are separated from proteins and blood cells. In this study, we describe a mixed-linker modulated synthesis of zirconium-based metal–organic frameworks for efficient removal of uremic toxins. We determined that the efficient adsorption of uremic toxins is achieved by optimizing the ratio between −amino functionalization of the UiO-66 structure with 75% of −NH2groups within organic linker structure. The maximum adsorption of hippuric acid and 3-indoloacetic acid was achieved by UiO-66-NH2(75%) and by UiO-66-NH2(75%) 12.5% HCl prepared by modulated synthesis. Furthermore, UiO-66-NH2(75%) almost completely adsorbs 3-indoloacetic acid bound to bovine serum albumin, which was used as a model protein to which uremic toxins bind in the human body. The high adsorption capacity was confirmed in recyclability test, which showed almost 80% removal of 3-indoloacetic acid after the third adsorption cycle. Furthermore, in vitrocytotoxicity tests as well as hemolytic activity assay have proven that the UiO-66-based materials can be considered as potentially safe for hemodialytic purposes in living organisms.

In this study, we present a modulated synthesis nanocrystalline defective UiO-66 metal–organic framework as a potential chloroquine diphosphate (CQ) delivery system. Increasing the concentration of hydrochloric acid during the modulated synthesis resulted in a considerable increase of pore volume, which enhanced the CQ loading in CQ@UiO-66 composites. Drug release tests for CQ@UiO-66 composites have confirmed prolonged CQ release in comparison with pure CQ. In vivo tests on a Danio reiromodel organism have revealed that CQ released from CQ@UiO-66 25% showed lower toxicity and fewer cardiotoxic effects manifested by cardiac malformations and arrhythmia in comparison to analogous doses of CQ. Cytotoxicity tests proved that the CQ loaded on the defective UiO-66 cargo resulted in increased viability of cardiac cells (H9C2) as compared to incubation with pure CQ. The experimental results presented here may be a step forward in the context of reducing the cardiotoxicity CQ.

Commissioning of new dissolved air flotation (DAF) installations and optimization of already existing installations takes at least one year of laboratory and pilot plant experiments. Such studies are labor-intensive. Using mathematical modeling, it is possible to minimize time and costs. For such purposes, mathematical model of the DAF process was developed based on the law of momentum (impulse) behavior and Navier–Stokes equations. The model allows to describe the kinetic relations between the water stream, air bubbles and aggregates arising as a result of coagulation of surface water pollution. The model takes into account the exchange of impulses between different phases as a result of laminar and turbulent flow. The developed model was used to prepare a simulation computer program. In order to check the feasibility of the model, laboratory tests were carried out under static conditions. Comparison of the results of laboratory tests with the results of computer simulation showed its suitability for analyzing the effectiveness of removing solid phase from water by means of dissolved air flotation. Proposed model was also compared with models proposed by different authors.

Innovative structured catalyst supports, like solid foams, wire gauzes, and short-channel structures, are considered in methane catalytic combustion. For comparison, classical supports such as packed beds and monoliths are also taken into account. Moreover, two catalysts, displaying “fast” and “slow” kinetics, are examined. The performance efficiency criterion is applied to account for a balance between the process conversion, mass transfer, and flow resistance. Another “technological” approach compares reactor length and the corresponding pressure drop required to reach the desired conversion rate. Results indicate that wire gauze, solid foam, and short-channel structure are highly promising catalyst supports due to their intense heat/mass transfer and moderate flow resistance, particularly for fast catalytic reactions. For slow reactions, monoliths seem to be the best as they exhibit the lowest flow resistance.

The determination of radium isotopes in drinking water by liquid scintillation technique requires some reagents that are used for separating radium from water samples. One of the main reagents is BaCl2·H2O. This paper presents the study of this compound and shows that barium chloride reagent is naturally contaminated with226Ra. The 226Ra activity concentration in BaCl2·H2O reagent produced by chemical companies from Poland and other countries is equal to a few dozen Bq/kg. Furthermore, 14 mL of 0.10 M BaCl2·H2O solution is the optimum amount which should be used for the chemical procedure. At the optimum amount of barium chloride and 2-hour measurement, the detection limit of 226Ra and 228Ra of the liquid scintillation counting method is equal to 5 and 30 mBq per sample, respectively.

The paper presents the physical base of the numerical system for analyse and modelling acoustic fields generated by an acoustic head of arbitrary construction. The elaborated system allows to analyse the sending-receiving multielements ultrasound heads. Nowadays the system makes possible to analyse the propagation of pressure waves through various acoustic media. The system enables the design of acoustical sources with appropriate directional characteristics, which in acoustooptic systems are applied. The expansion of the system will allow to use it for designing of ultrasound devices for investigation of biological tissues and for monitoring of mechanical systems. In the work, the experimental results of acoustical visualization of biological phantom of neoplasmatic degradation are presented.

The rules and capabilities of macro-strains identification method with the use of optical interference for identifying initial phase of plastic deformation process in steels with material instability were discussed in the work. It was also shown how the technique run in presentation of the initial phase of yielding progress. As the example for illustration of discussed method real capabilities the course of plastic deformations beginning in the tension tests of 15CrMo and 34CrNiMo6 steel samples was shown as well as the course of test of pure and simple bending for the steel 15CrMo beam. Namely, the sequence of interference fringes pictures showing the formation of plastic strains correlating to the points on the tensile test curve was presented. For bending process the pictures were correlated with the point on the graph of dimensionless bending moment versus maximal strain measured by the strain gauge

The paper attempts to clarify the differences between theoretical and experimental values of elastic bearing capacity for shields with openings under tension. The discrepancies occur between the experimental and the FEM calculations results which were realized by team of Institute of Applied Mechanics of Cracow University of Technology.For the purpose of comparative analysis one performed FEM calculations of the 15CrMo steel shield of geometry which was the geometry of shields being the subject of the experiments. The material model assumed in the FEM calculations was the elastic-plastic steel with the small linear reinforcement. In the calculations it was failed to obtain analogous plastic deformation schemes as in the experiments. There was obtained a similarity between the plastic zones shape and dimensions obtained from FEM calculations and for plastic zones shape and dimensions from experiments for loadings which exceed the experimental elastic bearing capacity for about 20%.

In protected areas, outdoor recreation, and nature-based tourism can act as potential stressors for wildlife. Given the growing demand for nature recreation, the consequences of high tourist visitation on wildlife need to be assessed in order to avoid incompatibilities between public use and species protection goals. The Tatra National Park (Poland), in the Carpathian Mountains, is a unique alpine ecosystem visited by three million tourists per year. It hosts the only native population of an endemic subspecies of chamois (Rupicapra rupicapra tatrica). We investigated the effects of tourist disturbance, the number of visitors, and the season on the concentration of fecal cortisol metabolites (FCM) in Tatra chamois in 2009. FCM levels of chamois were significantly higher and showed higher variation at high tourist disturbance (mean ± SD, 46.2 ± 31.53 ng/g, n= 56) than at low disturbance sites (mean ± SD, 17.2 ± 8.05 ng/g, n= 38). Stress levels increased with the number of visitors and therefore showed a peak in summer, coinciding with the highest number of visitation to the national park. A large portion of chamois habitat in Tatra National Park is within the area of influence of the touristic trail network. The temporal or permanent creation of areas free of disturbance in protected areas should be considered, especially in the periods of high tourist visitation. This study highlights the need to monitor the effects of tourist activities on wildlife and to implement new policies in the management of protected areas.In protected areas, outdoor recreation, and nature-based tourism can act as potential stressors for wildlife. Given the growing demand for nature recreation, the consequences of high tourist visitation on wildlife need to be assessed in order to avoid incompatibilities between public use and species protection goals. The Tatra National Park (Poland), in the Carpathian Mountains, is a unique alpine ecosystem visited by three million tourists per year. It hosts the only native population of an endemic subspecies of chamois (Rupicapra rupicapra tatrica). We investigated the effects of tourist disturbance, the number of visitors, and the season on the concentration of fecal cortisol metabolites (FCM) in Tatra chamois in 2009. FCM levels of chamois were significantly higher and showed higher variation at high tourist disturbance (mean ± SD, 46.2 ± 31.53 ng/g, n= 56) than at low disturbance sites (mean ± SD, 17.2 ± 8.05 ng/g, n= 38). Stress levels increased with the number of visitors and therefore showed a peak in summer, coinciding with the highest number of visitation to the national park. A large portion of chamois habitat in Tatra National Park is within the area of influence of the touristic trail network. The temporal or permanent creation of areas free of disturbance in protected areas should be considered, especially in the periods of high tourist visitation. This study highlights the need to monitor the effects of tourist activities on wildlife and to implement new policies in the management of protected areas.

Abstract: The doses of gamma radiation, concentrations of radium isotopes in water and sediments, radon concentration and concentration of alpha potential energy of radon decay products in the copper ore mine and in the mining region in the vicinity of Lubin town in Poland are presented. These data served as a basis for the assessment of radiological hazard to the mine workers and general public. The results of this assessment indicate that radiological hazard in the region does not differ substantially from typical values associated with natural radiation background. The calculated average annual effective dose for copper miners is 1.48 mSv. In general, copper ore mines can be regarded as radiologically safe workplaces.

Abstract: In the Lower Silesia region, in the vicinity of Kletno town (near Klstrokodzko), there are remainders of uranium ores being mined there, such as dump sites, abandoned pits and the like. Extensive research has indicated an increase in radioactivity there. The present research was aimed at defining the radioactive contamination in the neighborhood of Kletno. The research involved gauging the radiation background, especially at the mine dumps and measuring the concentration of natural radioactive isotopes and Cs in the rocks and soil. Besides, the concentration of radium isotopes in waters was determined. Two spots only were found with higher radiation levels. A method for dealing with radiation hazards is proposed. Water analyses have indicated that flushing of radium isotopes from the rock-mass and the dumps is not significant. Therefore, it can be concluded that uranium ore mining in the region of Kletno has not caused any significant radioactive contamination.