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Potentially toxic elements (PTEs) and ecological risk at waste disposal sites: An analysis of sanitary landfills
Get PDFThis study presents an analysis of soil contamination caused by Ni, Zn, Cd, Cu, and Pb at municipal solid waste (MSW) landfills, with a focus on ecological risk assessment. The approach aims to assess how different landfill practices and environmental conditions affect soil contamination with potentially toxic elements (PTEs) and associated environmental risks. Soil samples were collected from MSW landfills in Poland and the Czech Republic. The research included a comprehensive assessment of PTEs in soils in the context of global environmental regulations. The degree of soil contamination by PTEs was assessed using indices: Geoaccumulation Index (Igeo), Single Pollution Index (Pi), Nemerow Pollution Index (PN), and Load Capacity of a Pollutant (PLI). The ecological risk was determined using the Risk of PTEs (ERi) and Sum of Individual Potential Risk Factors (ERI). The maximum values of the indicators observed for the Radiowo landfill were as follows: Igeo = 4.04 for Cd, Pi = 24.80 for Cd, PN = 18.22 for Cd, PLI = 2.66, ERi = 744 for Cd, ERI = 771.80. The maximum values of the indicators observed for the Zdounky landfill were as follows: Igeo = 1.04 for Cu, Pi = 3.10 for Cu, PN = 2.52 for Cu, PLI = 0.27, ERi = 25 for Cd, ERI = 41.86. The soils of the tested landfills were considered to be non-saline, with electrical conductivity (EC) values less than 2,000 μS/cm. Varying levels of PTEs were observed, and geostatistical analysis highlighted hotspots indicating pollution sources. Elevated concentrations of Cd in the soil indicated potential ecological risks. Concentrations of Cu and lead Pb were well below the thresholds set by the environmental legislation in several countries. In addition, Ni concentrations in the soils of both landfills indicated that the average levels were within acceptable limits. Principal Component Analysis (PCA) revealed common sources of PTEs. The identification of specific risk points at the Radiowo and Zdounky sites contributes to a better understanding of potential hazards in landfill environments. By establishing buffer zones and implementing regular maintenance programs, emerging environmental problems can be addressed in a timely manner.O
Elimination of Curtobacterium sp. strain A7_M15, a contaminant in Prunus rootstock tissue culture production, using reduced graphene oxide-silver-copper and silver-selenium nanocomposites
Get PDFBackground: Bacterial contamination poses a high risk to the successful establishment and maintenance of plant tissue cultures. The aim of this study was to identify the isolates representing the frequent bacterial contaminants of Prunus rootstock tissue cultures and to determine the most effective concentration of nanomaterials for Curtobacterium sp. strain A7_M15 elimination without a negative impact on explants. Results: Six Curtobacterium sp. strains were isolated and identified, and the whole-genome sequence was obtained for strain A7_M15. Two nanocomposites, reduced graphene oxide-copper-silver and silver-selenium, with the highest bactericidal activity were selected for elimination of Curtobacterium sp. contamination in Gisela 5 rootstock tissue cultures. Both nanocomposites showed 100% inhibition of bacterial plaque formation on culture medium at concentrations of 100, 200 and 400 mg L-1 Ag (2 x-8 x MBC). The quantity of Curtobacterium sp. on culture medium assessed using cfu enumeration was reduced by 92% and 74% in comparison to the positive control after treatment with reduced graphene oxide-silver-copper and silver-selenium at a concentration of 200 mg L-1 Ag, respectively. None of the tested concentrations resulted in a decrease in Curtobacterium sp. quantity in explants. Curtobacterium sp. was detected in donor Gisela 5 plants, indicating an endophytic character of this bacterium. The dry weight of explants was not negatively affected by the application of nanocomposites regardless of concentration, and no detrimental effect of either nanocomposite at 100 or 200 mg L-1 Ag on the surface covered by plants was observed. Conclusions: Reduced graphene oxide-silver-copper and silver-selenium nanocomposites at 200 mg L-1 Ag effectively limited the Curtobacterium sp. presence in micropropagated Prunus rootstock without causing phytotoxicity; therefore, those treatments could be offered as prevention with a high activity against bacterial contamination in plant tissue cultures.O
Interactions between broiler parent stock age and egg pre-incubation duration: Effects on embryo development, hatchability, day-old chick weight, and yolk sac weight
Get PDFEgg storage is a common practice in commercial hatcheries, but prolonged storage can negatively impact hatchability, causing a significant problem for the poultry industry. Repeated pre-incubation could mitigate the decline depending on the age of the parent stock. The study investigated the interactions between parent stock age (30, 45, and 58 weeks) and repeated pre-incubation on the hatchability and embryo development of 15-day stored eggs from Ross 308 parent stock. Three different pre-incubation durations were employed during storage: no pre-incubation and twice at the 5th and 10th days of egg storage for either 4 or 8 h. For each parent stock age, 3 600 eggs collected on the same day from the same parent stock were used for hatchability assessment. The duration of pre-incubation was determined as the eggshell temperature increased from 28 oC to a maximum of 35 oC and then cooled to 28 oC; the persistency at 35 oC was either 1 or 4 h for the total pre-incubation period. The hatchability of both set and fertile eggs and early, middle, and late embryonic mortality depended on the parent stock's age (P < 0.001). Pre-incubation alone did not have any impact on hatchability. Conversely, a significant interaction was observed between parent stock age and pre-incubation duration on the hatchability of fertile eggs (P = 0.001). At 30 weeks of parent stock age, both durations of pre-incubation positively influenced the hatchability. At 45 weeks of parent stock age, pre-incubation length had no effect on hatchability. At 58 weeks of parent stock age, a longer pre-incubation period, 2 x 8 h, was associated with decreased hatchability. Early embryonic mortality was not influenced by pre-incubation. However, a significant interaction was observed (P = 0.003). At 30 weeks of parent stock age, both short and long lengths of pre-incubation were associated with a decrease in early embryonic mortality. However, at 45 and 58 weeks, pre-incubation did not significantly affect early embryonic mortality. Additionally, longer pre-incubation periods significantly increased middle mortality compared to untreated eggs (P = 0.035). The median of embryos development for untreated eggs was the same across all ages (stage 10). In the older parent stock (45 and 58 weeks), repeated pre-incubation increased variability in embryos development, while in the younger parent stock, repeated pre-incubation decreased variability in embryo development. In conclusion, the duration and the frequency of pre-incubation should be specified based on the age of the parent stock.O
The Ecological Potential of Poplars (Populus L.) for City Tree Planting and Management: A Preliminary Study of Central Poland (Warsaw) and Silesia (Chorzów)
Get PDFUrban environments face escalating challenges due to uncontrolled urbanization, rapid population growth, and climate changes, prompting the exploration of sustainable solutions for enhancing urban green spaces (UGSs). For this reason, poplars (Populus L.), due to their rapid growth, wide range adaptability to environmental conditions and versatility of use, have emerged as very promising. This comprehensive review synthesizes current knowledge regarding poplar's application in urban landscapes, emphasizing its multifaceted contributions and benefits. However, challenges arise from the variable lifespans of different poplar cultivars, necessitating strategic management approaches. Selecting cultivars based on growth rates, root system characteristics, and adaptability to urban conditions is pivotal. Adaptive replanting strategies, incorporating species with varying lifespans, offer solutions to maintain continual greenery in urban landscapes. Collaborative efforts between researchers, urban planners, and policymakers are essential for devising comprehensive strategies that maximize benefits while addressing challenges associated with their variable lifespans. In conclusion, harnessing poplar's potential in urban greenery initiatives requires a balanced approach that capitalizes on their benefits while mitigating challenges. Further research and adaptive strategies are crucial for sustained and effective utilization to create resilient and vibrant urban landscapes.O
Application of the GIS methods along with measured parameters to identify the NH4+ origin in the Hranice Karst (Czech Republic)
Get PDFThe study aims to determine the source of NH4+ ions in the mineral waters of the Hranice Karst. The study area is located in the eastern part of the Czech Republic, Europe. The area is known mainly for its carbon dioxide of deep origin; the gas was the factor that enabled the formation of hypogene karst, in the Palaeozoic limestones, as well as warm mineral waters. The limestones of the area are covered by Neogene (Miocene) sediments of variable thickness and lithology. Recurrent sampling was done at 36 sites. A total of 96 surface water samples, 65 borehole water samples and 96 karst water samples were assessed. Major anions, cations and the content of nitrogen and its forms were determined for all water samples. The soil types were characterised by a field pedological survey. The normalised difference vegetation index was calculated in QGIS and vegetation vitality was evaluated. Since places with remarkably low vegetation index were found to be linked to the occurrence of Miocene sandstones, they represent points of rather fast entry of rainwater into the ground. As the presence of carbon dioxide creates an anoxic setting underground, the entering nitrates are transformed into NH4+ ions. This mechanism of transformation within the nitrogen cycle explains the presence of NH4+ ions in areas with elevated CO2.OA-hybri
Nanoformulation of the Broad-Spectrum Hydrophobic Antiviral Vacuolar ATPase Inhibitor Diphyllin in Human Recombinant H-ferritin
Get PDFBackground: As highlighted by recent pandemic outbreaks, antiviral drugs are crucial resources in the global battle against viral diseases. Unfortunately, most antiviral drugs are characterized by a plethora of side effects and low efficiency/poor bioavailability owing to their insolubility. This also applies to the arylnaphthalide lignin family member, diphyllin (Diph). Diph acts as a vacuolar ATPase inhibitor and has been previously identified as a promising candidate with broad-spectrum antiviral activity. However, its physicochemical properties preclude its efficient administration in vivo, complicating preclinical testing. Methods: We produced human recombinant H- ferritin (HsaFtH) and used it as a delivery vehicle for Diph encapsulation through pH-mediated reversible reassembly of HsaFtH. Diph nanoformulation was subsequently thoroughly characterized and tested for its non-target cytotoxicity and antiviral efficiency using a panel of pathogenic viral strain. Results: We revealed that loading into HsaFtH decreased the undesired cytotoxicity of Diph in mammalian host cells. We also confirmed that encapsulated Diph exhibited slightly lower antiviral activity than free Diph, which may be due to the differential uptake mechanism and kinetics of free Diph and Diph@HsaFtH. Furthermore, we confirmed that the antiviral effect was mediated solely by Diph with no contribution from HsaFtH. Conclusion: It was confirmed that HsaFtH is a suitable vehicle that allows easy loading of Diph and production of highly homogeneous nanoparticles dispersion with promising broad-spectrum antiviral activity.O
Militant democracy: firewall as a restriction of fundamental civil liberties?
No full textČlánek se zaměřuje na představení konceptu militantní demokracie, který je v českém akademickém prostředí diskutován již několik let. Praktiky militantní demokracie lze vnímat jako určitý "firewall" proti oslabování demokratických základů státu. Na druhou stranu jsou praktiky militantní demokracie kritizovány za omezování základních lidských práv a svobod (například svoboda projevu, právo sdružování, právo shromažďování atd.). Text se zabývá vybranými aspekty těchto složitých debat.The paper will focus on introducing the concept of militant democracy, which has been discussed in the Czech academic environment for several years. The practices of militant democracy can be seen as a certain "firewall" against the weakening of the democratic foun-dations of the state. On the other hand, the practices of militant democracy are criticized for restricting basic human rights and freedoms (for example, freedom of expression, right of association, right of assembly, etc.). The text will cover selected aspects of these complicated debates.Published Versio
The urban greenery of the Brno city as an environment for people's recreation as well as the life of large wild mammals
No full textIn the model area of the Brno city, research focused on monitoring the occurrence of wild mediumsized and large mammals is underway. The task of the project is to find out the species spectrum of mammals occurring in the landscape structure of the city, to estimate their density, risk situations and to provide guidance to the state administration and self-government for their management and solving situations. After the first year of the solution, it is possible to present the results from the part of the research dealing with the regular monitoring of urban greenery. Paired areas of large urban parks, forest parks, areas after mining, horticultural colonies and suburban forests were selected. These were inspected regularly, once a month, 2 hours after sunset with a thermal imaging device. The following species were recorded: domestic cat, red squirrel, marten, red fox, wild boar, roe deer, badger and raccoon dog. Free-living mammals thus adapt to life in an urban environment, get used to the presence of humans, and become part of the urban landscape. This brings with it many negative consequences that will have to be actively addressed sooner or later.Published Versio
Effect of milking method and season on phthalate content in cow milk from organic production
Get PDFDibutyl phthalate (DBP) and diethylhexyl phthalate (DEHP) content was determined by the high-performance liquid chromatography in the milk samples either mechanically or manually taken from 10 dairy cows in January, April, July and October (altogether 344 milk samples were collected). Milking method and season accounted for 23 and 77%, and 33 and 36% of the explained variability of DBP and DEHP content, respectively. Content of DBP in mechanically collected samples was higher in comparison with manually collected milk: 10.0 vs. 6.7 mg kg-1 milk (P < 0.05). Irrespective of the milking method, DBP content differed significantly (P < 0.05) between samples collected in January (6.6 mg kg-1), July (4.2 mg kg-1) and October (20.0 mg kg-1). In the case of DEHP, only differences between April and October milk were found out (0.03 vs. 0.96 mg kg-1; P < 0.05). Concentration of DBP in both mechanically and manually collected milk increased according to a polynomial function from spring to autumn (P < 0.01). Thirty times higher average DBP content than DEHP content was contrary to expectation. A migration of DBP in milk apart from the milking equipment (probably by contaminated silage) was more important in comparison with DEHP.OA-hybri
Key Criteria Influencing Stakeholders' Decision-making about PB Continuation: The Case of the Czech Republic
Get PDFParticipatory budgeting (PB) is a modern trend involving citizens in decisions on distributing public resources. Assuming that the identified drawbacks of PB are described as internal and external factors, simple criteria were developed to predict the fate of PB. These criteria reflect stakeholders' decisions about PB continuation in the future. Using panel data between 2017-2022 from the Czech Republic, it appears that the selected criteria were evaluated as an upgrading process, signalling the continuation of PB. However, this does not mean abandoning the process in the case of downgrading. The results indicate a certain probability for upgrading PB to continue, while the fate of downgrading PB is indeterminate and could depend on other factors. In the case of new governance after an electoral change, using the criteria could help explain the actual situation regarding the interest of stakeholders in PB.O