The article presents the current state of the CNG market used as an alternative fuel for car engines. Attention was paid to European Union directives requirements and the current state of the directives’ fulfillment. The economic aspect of CNG usage was analyzed and the approximate costs of driving 10,000 km on different fuels in the last four years were presented. The PtG process which uses electric energy (hydrogen production) and carbon dioxide captured from the flue gas for the production of synthetic methane were discussed. The scheme of the SNG plant with the indication of its most important components was presented, and attention was paid to the mutual complementation of PtG technologies with carbon dioxide capture technology. The benefits of synthetic methane production are presented and the use of compressed natural gas to power engines in vehicles has been described. First, the focus was on the single-fuel use of CNG in bus and truck engines, paying particular attention to the ecological aspect of the implemented solutions. It has been shown that the use of compressed natural gas will reduce almost 100% of the particulates emission from the combustion process. The advantages and disadvantages of the alternative fuel supply are given. Next, the aspect of dual-fuel use in diesel engines was analyzed on the example of a smaller engine. The degree of reduction of harmful compounds emission from the combustion process is shown. Finally, attention was paid to the possible scale effect, referring to the number of motor vehicles in Poland.

This paper presents a preoperative hip reconstruction method with diagnosed osteoarthritis using Durom Hip Resurfacing System (DHRS). The method is based on selection and application of the resurfacing to the pelvis reconstructed on the basis of computed tomography. Quality and geometrical parameters of distinguished tissues have a fundamental significance for locating and positioning the acetabular and femoral components. The application precedes the measurements of anatomical structures on a complex numerical model. The developed procedure enables functional selection of endo-prosthesis and its positioning in such a way that it secures geometric parameters within the bone bed and the depth , inclination angles and ante-version of the acetabular component, the neck-shaft angle and ante-torsion angle of the neck of the femoral bone, and reconstruction of the biomechanical axis of the limb and the physiological point of rotation in the implanted joint. Proper biomechanics of the bone-joint complex of the lower limb is determined by correlation of anatomical-geometrical parameters of the acetabular component and parameters of the femoral bone.

Introduction: Interventional cardiology (IC) is a rapidly expanding fi eld of medicine. Medical studies should provide students the necessary level of knowledge about new techniques in IC. The aim of the study was to assess the medical students’ knowledge about various new areas of IC. Material and methods: Self-designed questionnaire was used to assess student’s knowledge. It contained 31 questions. Th e initial 3 questions concerned general information, the remaining ones were related to diff erent IC techniques: Transcatheter Aortic Valve Implantation (TAVI), Bioresorbable Vascular Scaff old (BVS), percutaneous mitral regurgitation repair methods, Left Atrial Appendage Occlusion (LAAO), Renal DeNervation (RDN), Balloon Aortic Valvuloplasty (BAV) and Atrial Septal Defect/Persistent Foramen Ovale (ASD/PFO). One point for each correct answer was awarded. Results: In our study participated 104 students. Mean score was 15.9 ± 5.8 points. 24% of participants were 3rd year students, 38% — 4th, 20% — 5th and 18% — 6th. Th ere was no diff erences in level of knowledge between students of diff erent years of studies (p = 0.2). Students from Students Research Groups (SRG) achieved higher score in comparison with students no attending SRG (19.3 ± 6.3 vs 13.3 ± 3.7; p <0.001) as well as students interested in cardiology comparison with other (19.6 ± 5.9 vs 13.0 ± 3.8; p <0.001). Students from SRG and interested in cardiology reached also higher results in practically every area of IC in comparison with other. Conclusions: Participants have insuffi cient, outdated and incomplete knowledge of new methods in IC. Th ere was no signifi cant diff erence in students of diff erent years of studies. Students belonging to cardiological SRG and interested in cardiology have greater knowledge in IC.

The study aimed to determine the psychological aspects of captivity in the War in the East of Ukraine: the purposes and motives of the capture of Ukrainian Forces (UF); the types of captivity and their specifics; the stages and phases of captivity. The measures included a questionnaire and interview method. 694 former prisoners of war (POWs) (servicemen of the Armed Forces of Ukraine and soldiers of volunteer battalions) participated in the study. The research results revealed the purposes of capturing UF: to stop UF advance; obtaining intelligence; demoralization of UF; demonstration of military superiority; capturing prisoners for exchange; unwillingness to kill; receiving a ransom. The UF invaders were military units, professional mercenaries’ units, and gang formation units. The stages of captivity (capture and transportation to a place of permanent detention; first interrogation; being held captive; exchange of POWs and homecoming) were characterized by intimidation, aggression, physical, psychological and sexual violence against POWs, the purposeful creation of an environment of mass psychosis among POWs. Captivity kept the POWs in constant tension and fear. The altered mental status of POWs took place in successive phases: life reactions, shock, psychological demobilization, denouement, recovery, and conflict phase.

Polish research in the history of the Reformation still leaves many topics and figures barely described or analysed. Among the prominent Protestant theologians who are virtually unknown in Poland, the name of Philipp Melanchthon deserves special recognition. According to the author, this situation requires indepth research on Melanchthon; also, editions of historic sources and letters of Protestant theologians should be launched. The material that requires re-edition and, in some cases, translation into Polish includes works of authors such as Aleksander Brückner and Theodor Wotschke, who conducted their research on Protestants several decades ago.

The chevkinite group of minerals are REE,Ti-silicates increasingly recognized as widespread accessory phases in a wide range of igneous and metamorphic parageneses. Members of the group are here recorded from five localities in Poland: a two-pyroxene andesite from the Kłodzko-Złoty Stok intrusion, a trachyandesite intrusion north of the Pieniny Mountains, a rapakivi-type granite from the Krasnopol intrusion, an anorthosite from the Suwałki Anorthosite Massif, and nepheline syenite from the Ełk syenite massif. Specific members found are chevkinite-(Ce), perrierite-(Ce) and, potentially, the Al-dominant analogue of perrierite-(Ce). The case is made that chevkinite-group minerals will, through systematic investigation, be found in a wide range of Polish igneous and metamorphic rocks.

Nowadays, aluminum-based composites have been produced by pure alumina (Al2O3) or pure graphene nanoplatelets (GNPs) in aluminum matrix because of the high compressive strength of alumina and the solid lubricant properties of graphene. However, there are no studies on the influence of both alumina and graphene reinforced aluminum composites. In this study, Al-Al2O3 and Al-Al2O3-GNPs composites were reinforced with pure alumina (between 0 and 30 wt.%), pure graphene (0, 0.1, 0.3, 0.5 wt.%), and their hybrid forms (Al2O3-GNPs) by the powder metallurgy method. This method involved ultrasonic dispensing, mixing, filtering, drying, pressing, and sintering processes. From the test results, the micro Vickers hardness of pure aluminum (28.2±1 HV) improved to 51.5±0.8 HV (Al-30Al2O3) and 63.1±1 HV (Al-30Al2O3-0.1GNPs). Similarly, the ultimate compressive strength (UCS) enhanced from 92.4±4 MPa (pure aluminum) to 165±4.5 MPa (Al-30Al2O3) and 188±5 MPa (Al-30Al2O3-0.1GNPs), respectively. In conclusion, the Vickers hardness and ultimate compressive strength of aluminum hybrid composites improved up to 0.1 wt.% graphene content. After 0.1 wt.% graphene content, these mechanical properties decreased because of the clumping of graphene nanoparticles.

Hydrogen sulfide (H2S) regulates many critical processes of plants. The effect of sodium hydrogen sulfide as H2S agent was investigated in basil plants under cadmium stress. A completely randomized design with three different concentrations (0, 50 and 100 μM) of CdCl2 and two levels of NaHS (0 and 100 μM) was used in this study. Cadmium exposure reduced growth parameters and relative water content. Cd also caused a significant increase in ion leakage and higher oxidative stress in terms of lipid peroxidation and H2O2 production. Although exogenous NaHS used in non-stressed control plants negatively affected growth and physiological parameters, it improved the root/shoot length ratio and fresh weight in basil plants under Cd 50 μM exposure. Moreover, NaHS alleviated deleterious effects of cadmium on ion leakage, relative water content and photosynthetic pigments of leaves. The activity of antioxidant enzymes like catalase, peroxidase and ascorbate peroxidase were also enhanced by NaHS in plants under moderate cadmium stress. Our results show that NaHS 50 μM ameliorates growth retardation induced by cadmium 50 μM stress in basil plants, probably through regulating physiological parameters such as photosynthetic pigments content, relative water content and the activity of antioxidant enzymes.