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In this study, we investigated the Eurasian eagle owl (Bubo bubo) breeding in lowland forests in the trans-border area between western Slovakia, eastern Austria, and southern Moravia. The research provides new information on the reuse of nests by eagle owls and presents initial insights into population density and trends of eagle owls in the March-Thaya floodplains. Our 19-year monitoring has shown that the eagle owl has become a widespread breeder over the study area, with an increasing population trend. A total of 151 breeding attempts by eagle owls have been identified, occupying 82 natural nests (originally built by at least nine species of birds) and 12 artificial nests. With an average of 6.2 active nests per 100 km2 and a maximum of 17 active nests found in 2021 (~10.6 pairs per 100 km2), our findings represent one of the highest eagle owl breeding densities found, especially in comparison with core populations nesting in the mountains (the Carpathians, north-eastern Alps and the Bohemian Massif). Regarding the dynamics of nest reuse, our results reveal that only a third of nests used by eagle owls were reused by other raptors or storks (Ciconia sp.). Almost 50% of the natural nests in which eagle owl bred, subsequently disintegrated after the owlets had fledged. Lastly, black stork (Ciconia nigra) nests re-used by eagle owls were twice as likely to have disintegrated after the owlets had fledged than nests built by other bird species. Our results suggest that black stork nests in the March and Thaya floodplain forests are most susceptible to destruction.

Abhilash D Pandya,1 Eliézer Jäger,2 Shahla Bagheri Fam,3 Anita Höcherl,2 Alessandro Jäger,2 Vladimir Sincari,2 Bo Nyström,4 Petr Štěpánek,2 Tore Skotland,5 Kirsten Sandvig,5,6 Martin Hrubý,2 Gunhild M Mælandsmo1,71Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, Oslo, Norway; 2Institute of Macromolecular Chemistry v.v.i, Academy of Sciences of the Czech Republic, Prague, Czech Republic; 3Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, Oslo, Norway; 4Department of Chemistry, University of Oslo, Oslo, Norway; 5Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, The Norwegian Radium Hospital, Oslo, Norway; 6Department of Biosciences, University of Oslo, Oslo, Norway; 7Institute of Medical Biology, Faculty of Health Sciences, The Arctic University of Norway – University of Tromsø, Tromsø, NorwayBackground: Reactive oxygen species (ROS), such as hydrogen peroxide and superoxide, trigger biodegradation of polymer-based nanoparticles (NPs) bearing pinacol-type boronic ester groups. These NPs may selectively release their cargo, in this case paclitaxel (PTX), at the high levels of ROS present in the intracellular environment of inflamed tissues and most tumors.Purpose: The main objective was to determine anti-tumor efficacy of PTX-loaded ROS-sensitive NPs and to examine whether macrophage infiltration had any impact on treatment efficacy.Methods: NPs were synthesized and their characteristics in the presence of H2O2 were demonstrated. Both confocal microscopy as well as flow cytometry approaches were used to determine degradation of ROS-sensitive NPs. HeLa cells were cultured in vitro and used to establish tumor xenografts in nude mice. In vivo experiments were performed to understand toxicity, biodistribution and anti-tumor efficacy of the NPs. Moreover, we performed immunohistochemistry on tumor sections to study infiltration of M1 and M2 subsets of macrophages.Results: We demonstrated that PTX delivered in NPs containing a ROS-sensitive polymer exhibits a better anti-tumor efficacy than PTX in NPs containing ROS-non-sensitive polymer, free PTX or Abraxane® (nab-PTX). The biodistribution revealed that ROS-sensitive NPs exhibit retention in liver, spleen and lungs, suggesting a potential to target cancer metastasizing to these organs. Finally, we demonstrated a correlation between infiltrated macrophage subsets and treatment efficacy, possibly contributing to the efficient anti-tumor effects.Conclusion: Treatment with ROS-sensitive NPs containing PTX gave an improved therapeutic effect in HeLa xenografts than their counterpart, free PTX or nab-PTX. Our data revealed a correlation between macrophage infiltration and efficiency of the different antitumor treatments, as the most effective NPs resulted in the highest infiltration of the anti-tumorigenic M1 macrophages.Keywords: reactive oxygen species, ROS-sensitive nanoparticles, paclitaxel, treatment efficacy, macrophage infiltration

The article deals with the effect of an acidic environment on the mechanical properties of a Glass Fibre Reinforced Polymer (GFRP) grid. GFRP composites are prone to the absorption of surrounding media which are either of a liquid or gaseous state, and this may result in the degradation of their mechanical properties. The effect of an acidic environment is examined on specimens cut from a GFRP grid. The specimens were stored in an acidic bath (pH scale 2 – 2.5) for a period of 0 (reference specimen), 1000, 2000 and 6000 hours. The temperature of the acidic bath was 60°C. The specimens were then tested using three‒point bending and the interlamination shear strength test. During the tests, the load and deformation of the specimens were monitored and flexural strength instead and modulus of elasticity were determined. The characteristics of the specimens exposed to the acidic environment were compared with those of the reference specimen. The experiment demonstrated the effect an acidic environment can have on the properties of GFRP material.

Abstract Background Cryopreservation of stallion spermatozoa tends to cause plasma membrane damage due to the low ratio of cholesterol to phospholipids. Gums have been suggested as an alternative cryoprotectant to glycerol for stallion spermatozoa. Therefore, the present experiment was designed to verify whether the effect of addition of cashew gum (CG), or nanoparticles (NP) containing CG, to the extender before cooling on sperm quality in stallion semen. Ejaculates from 6 stallions were extended and split between six treatment groups (control, a-tocopherol [TOC], CG1, CG0.5, NP1 and NP0.5), stored in cryotubes at 4 °C. Results Aliquots were analysed by computer-assisted sperm motility analysis on the day of collection, and after 24 h and 48 h of cold storage. After 48 h, the total motility with NP1 (78.53 + 6.31%) was similar to control 85.79 + 6.31% at 0 h. The same pattern was observed for progressive motility. Membrane integrity assessed by flow cytometer was similar between control, TOC and G1 at all storage times. The DNA fragmentation in the control group increased at all time points, whereas chromatin integrity was maintained after 24 h in TOC and NP0.5 compared to 0 h. There was no increase in the proportion of live spermatozoa producing hydrogen peroxide, but there was a tendency for an increased proportion of spermatozoa in the live superoxide category in CG1 after 24 h cooled storage. Conclusions The addition of CG or CG-derived NP to extender for stallion semen was not harmful to the sperm cells.

The presented case demonstrates that acute lead poisoning may occur due to just short-term exposure to a mixture of lead-containing dust and ammunition. Such exposure may result in high blood lead levels persisting for years in the absence of any symptoms. A middle-aged male with a history of an approximately 7-day cleanup of an old recreational firing range with large ammunition and dust deposits presented to an emergency department with abdominal pain, dyspnea, fatigue and impaired cognitive function. Given his occupational history, specific tests were performed that showed high lead concentrations in both blood and urine. The patient was diagnosed with acute lead poisoning. He was started on chelation therapy that improved both clinical and laboratory parameters. Over a subsequent nearly 3-year follow-up, the patient’s blood lead levels fluctuated and continued to be increased. Given the absence of other sources of lead exposure, these were likely due to the formation of bone deposits. Med Pr. 2020;71(3):375–9

The article deals with the process of identification of competencies for commanders in leading units in military operations. The used methodology based on combined approach founded on selected competency rosters and its further modification seemed to be relevant and applicable in the Czech Armed Forces conditions. Military officer’s profiles anchored in the EU Commission Database for Armed Forces and in the EU Sectoral Qualifications Framework for Military Officer Profession have been proven as the most relevant frameworks of competencies. Both are formulated and structured to be as generic as possible for all officers regardless of their specialization. They were established on current theories and incorporate extensive amount of entries from various national sources. The resulting list of 24 generic competencies, selected from a total of 69 competencies analyzed, represents a possible example of a set of requirements imposed on the Czech Armed Forces officers.

The paper describes an experimental program for studying the fatigue performance of GFRP bars, which has been initiated by the authors. Two different test configurations were used to assess the fatigue behaviour. The bare specimens were tested within the first series. A modified gripping system was used to reduce eccentricity when the bar was not directly fixed. However, the boundary conditions seem to affect the results. The second series consisted of a set of specimens of bars embedded in concrete. This configuration seems appropriate for determination of fatigue life of GFRP bars. Two S-N curves for bare bars and bars embedded in concrete were created and compared. Significant reduction of interlaminar shear strength at the beginning of fatigue loading proved matrix or fibre/matrix interface damage.

High vaccination coverage among healthcare workers (HCWs) is crucial for managing the COVID-19 pandemic. The aim was to determine the demand for vaccination among all employees (n = 4553) of a tertiary care hospital after several weeks of the vaccine’s availability, and to analyze motives for acceptance and reasons for hesitancy through an anonymous online questionnaire. Upon the completion of data collection, the hospital’s vaccination coverage was at 69.8%. A total of 3550 completed questionnaires were obtained (2657 from vaccinated, 893 from unvaccinated employees). Significant predictors of vaccine acceptance were: age (odds ratio (OR) 1.01, 95% confidence interval (CI) 1.01–1.02), sex (OR (females) 0.58, 95% CI 0.45–0.75), job type (OR (non-physician HCWs) 0.54, 95% CI 0.41–0.72; OR (non-HCWs) 0.51, 95% CI 0.37–0.71), fear of COVID-19 (OR 1.4, 95% CI 1.34–1.46), history of COVID-19 (OR 0.41, 95% CI 0.34–0.49) and of influenza vaccination (OR 2.74, 95% CI 2.12–3.57). The most frequent motive for acceptance was the effort to protect family members (84%), while concerns about vaccine safety and side effects (49.4%), followed by distrust in the vaccine’s efficacy (41.1%) were the top reasons for hesitancy. To increase vaccination coverage among HCWs, it is necessary to raise awareness of vaccine safety and efficacy.

The dynamic analysis of footbridges became common in recent years, but the approach to modelling pedestrian induced load is still inconsistent. This paper compares two different ways of modelling single pedestrian load. The response of the structure to stationary pulsating force is compared to the results given by the same force moving along simply supported beam. 300 randomly generated beams were used in this parametric study to describe the relation among these two approaches and parameters of the structure. The proposed formula was successfully applied to get more realistic estimation of response of the structure to a single walking pedestrian using stationary pulsating force.