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Microbiological insight into various underground gas storages in Vienna Basin focusing on methanogenic Archaea
Get PDFIn recent years, there has been a growing interest in extending the potential of underground gas storage (UGS) facilities to hydrogen and carbon dioxide storage. However, this transition to hydrogen storage raises concerns regarding potential microbial reactions, which could convert hydrogen into methane. It is crucial to gain a comprehensive understanding of the microbial communities within any UGS facilities designated for hydrogen storage. In this study, underground water samples and water samples from surface technologies from 7 different UGS objects located in the Vienna Basin were studied using both molecular biology methods and cultivation methods. Results from 16S rRNA sequencing revealed that the proportion of archaea in the groundwater samples ranged from 20 to 58%, with methanogens being the predominant. Some water samples collected from surface technologies contained up to 87% of methanogens. Various species of methanogens were isolated from individual wells, including Methanobacterium sp., Methanocalculus sp., Methanolobus sp. or Methanosarcina sp. We also examined water samples for the presence of sulfate-reducing bacteria known to be involved in microbially induced corrosion and identified species of the genus Desulfovibrio in the samples. In the second part of our study, we contextualized our data by comparing it to available sequencing data from terrestrial subsurface environments worldwide. This allowed us to discern patterns and correlations between different types of underground samples based on environmental conditions. Our findings reveal presence of methanogens in all analyzed groups of underground samples, which suggests the possibility of unintended microbial hydrogen-to-methane conversion and the associated financial losses. Nevertheless, the prevalence of methanogens in our results also highlights the potential of the UGS environment, which can be effectively leveraged as a bioreactor for the conversion of hydrogen into methane, particularly in the context of Power-to-Methane technology.O
Natural conditions for heliophilous tree-species following forest dieback in temperate zone after periglacial habitats
Get PDFWidespread forest dieback following a series of exceptionally dry seasons has made restoration by relic heliophilous tree-species uncertain. Using logistic regression, we identified conditions suitable for relic Norway spruce (Picea abies /L./ Karst.), Scots pine (Pinus sylvestris L.), European larch (Larix decidua Mill.), birches (Betula sp.), poplars (Populus sp.) and willows (Salix sp.) by comparing the relief and bedrock under stands that died abruptly between 2018 and 2020 at temperate zone after periglacial habitats of the Czech Republic. Extent of forest dieback was determined through automated object analysis on the basis of vectorised Planet Scope and Sentinel-2 satellite images. The object analysis consisted of mainly spruce stands and dieback indicated by a deep inter-year decrease in the vegetation indices. The overall occurrence of tree-species in pure or mixed stands was determined from a polygon geodatabase of forest management plans, while growth condition types were determined by overlaying biogeographically subdivided polygons. Dead forests provided suitable conditions for mixed conifer, birch, and poplar stands on 64.4 % of the greywackes, acid metamorphites, and waterlogged sediments on broken plateaus, depressions, and slopes. In comparison, pure stands of relic tree-species can cover 35.6 % of dead forest area. Restoration of mixed forests differenting over a range of growth conditions seems to be suitable for adaptation to climate change impacts.O
Hidden Phytophthora diversity unveiled in tree nurseries of the Czech Republic with traditional and metabarcoding techniques
Get PDFPhytophthora diversity was examined in eight forest and ornamental nurseries in the Czech Republic. A leaf baiting isolation technique and, in two nurseries, also Illumina DNA metabarcoding were used to reveal the diversity of Phytophthora in soil and irrigation water and compare the efficacy of both approaches. In total, baiting revealed the occurrence of 12 Phytophthora taxa in 59.4% of soil samples from seven (87.5%) nurseries. Additional baiting of compost was carried out in two nurseries and two Phytophthora species were recovered. Irrigation water was examined in three nurseries by baiting or by direct isolation from partially decomposed floating leaves collected from the water source, and two Phytophthora species were obtained. Illumina sequencing of soil and water samples was done in two and one nurseries, respectively. Phytophthora reads were identified as 45 Phytophthora taxa, 15 of them previously unknown taxa from Clades 6, 7, 8 and 9. Another 11 taxa belonged to known or undescribed species of the oomycete genera Globisporangium, Hyaloperonospora, Nothophytophthora, Peronospora and Plasmopara. Overall, with both techniques 50 Phytophthora taxa were detected with five taxa (P. taxon organica, P. plurivora, P. rosacearum, P. syringae and P. transitoria) being exclusively detected by baiting and 38 only by DNA metabarcoding. Particularly common records in DNA barcoding were P. cinnamomi and P. lateralis which were not isolated by baiting. Only seven species were detected by both techniques. It is recommended to use the combination of both techniques to determine true diversity of Phytophthora in managed or natural ecosystems and reveal the presence of rare or unknown Phytophthora taxa.OA-hybri
Unlocking the power of nanomedicine: the future of nutraceuticals in oncology treatment
Get PDFCancer, an intricate and multifaceted disease, is characterized by the uncontrolled proliferation of cells that can lead to serious health complications and ultimately death. Conventional therapeutic strategies mainly target rapidly dividing cancer cells, but often indiscriminately harm healthy cells in the process. As a result, there is a growing interest in exploring novel therapies that are both effective and less toxic to normal cells. Herbs have long been used as natural remedies for various diseases and conditions. Some herbal compounds exhibit potent anti-cancer properties, making them potential candidates for nutraceutical-based treatments. However, despite their promising efficacy, there are considerable limitations in utilizing herbal preparations due to their poor solubility, low bioavailability, rapid metabolism and excretion, as well as potential interference with other medications. Nanotechnology offers a unique platform to overcome these challenges by encapsulating herbal compounds within nanoparticles. This approach not only increases solubility and stability but also enhances the cellular uptake of nutraceuticals, allowing for controlled and targeted delivery of therapeutic agents directly at tumor sites. By harnessing the power of nanotechnology-enabled therapy, this new frontier in cancer treatment presents an opportunity to minimize toxicity while maximizing efficacy. In conclusion, this manuscript provides compelling evidence for integrating nanotechnology with nutraceuticals derived from herbal sources to optimize cancer therapy outcomes. We explore the roadblocks associated with traditional herbal treatments and demonstrate how nanotechnology can help circumvent these issues, paving the way for safer and more effective cancer interventions in future oncological practice.O
Unraveling the ecotoxicological effects of micro and nano-plastics on aquatic organisms and human health
Get PDFPlastic pollution ranks among the most severe environmental disasters caused by humans, generating millions of tonnes of waste annually. The extensive and unregulated use of plastics has led to ecotoxicity and environmental imbalance. Microplastics (MPs) are prevalent in aquatic environments, and these MPs further degrade into even smaller particles known as nano-plastics (NPs). Both MPs and NPs impact the environment by readily absorbing organic pollutants and pathogens from their surroundings, owing to their bigger surface area to volume ratio. This review focuses on the source of origin, bioaccumulation, and potential impact of MPs and NPs on aquatic organisms and human health. Additionally, the review explores various methods employed for identification and quantification of these particles in aquatic ecosystems. Sufficient information is available on their characteristics, distributions, and effects on marine ecosystems compared with freshwater ecosystems. For plastic particles <10 μm, more toxicological effects were observed compared with larger size particles, in aquatic life. Understanding the mechanism of action and ecotoxicological effects of micro/nano-plastics on the health of aquatic life across various trophic levels, as well as human health, is of utmost importance. We address knowledge gaps and provide insights into future research approaches for a better understanding of the interactive mechanisms between binary pollutants.O
Crisis, conflict and uncertainty: a conceptualization of terms
No full textTento příspěvek se zaměřuje na konceptualizaci tří pojmů: krize, konflikt a nejistota. Cílem je přispět k lepšímu porozumění těmto jevům a vytvořit teoretický rámec pro jejich studium a analýzu. V úvodu jsou definovány tyto pojmy a jsou prezentovány různé přístupy k jejich výkladu a interpretaci. Dále se článek zaměřuje na vztah mezi těmito jevy a ukazuje, jak se mohou navzájem ovlivňovat a vzájemně se posilovat. Celkově tento teoretický příspěvek nabízí základní rámec pro studium těchto jevů, který může být užitečný pro odborníky v oblasti sociologie, politologie, bezpečnostních studií, ekonomie a dalších společenských věd.This paper focuses on the conceptualization of three concepts: crisis, conflict, and uncertainty. The aim is to contribute to a better understanding of these phenomena and to create a theoretical Framework for their study and analysis. In the introduction, these concepts are defined, and various approaches to their interpretation and explanation are presented. The article then focuses on the relationship between these phenomena and shows how they can influence each other and strengthen each other. Overall, this theoretical paper offers a basic framework for studying these phenomena, which can be useful for professionals in the fields of sociology, political science, security studies, economics, and other social sciences.Published Versio
Internal Image of Czech Tertiary Business Schools and Its Influence on The Interest of New Applicants for Study
Get PDFAttracting prospective students could be difficult and expensive. Candidates, when choosing a future school for their studies, consider a great number of factors. Information from official university websites does not suffice to persuade. Word of mouth plays a significant role, among others. The aim of this paper is to present findings about important factors influencing the overall satisfaction of current students with university life as well as their willingness to share positive references. The study took place in the Czech Republic with students attending business schools at universities. Primary data was collected via an online questionnaire with students with bachelor's, master's, and doctorate degrees (n = 274) and in-depth interviews (n = 10). Data was processed with regression analysis and Spearman's correlation coefficient. The main findings suggest that there is a close positive correlation between students' satisfaction and the willingness to recommend the university. The quality of student life and the reputation of the school were identified as the most important factors influencing this satisfaction and willingness to recommend.O
Response of Alnus glutinosa to Phytophthora bark infections at ambient and elevated CO2 levels
Get PDFIntroduction: Mortality of the riparian alder population caused by Phytophthora pathogens has been studied for over 20 years throughout Europe, recently gaining more importance in the context of evident climate change. The main objective of this study was to examine the pathogenicity of species from the "Phytophthora alni complex" present in the Czech Republic (P. x alni and P. uniformis) and P. plurivora to Alnus glutinosa seedlings grown at ambient and elevated CO2 concentration. Methods: An underbark inoculation test was performed with seedlings grown from seeds collected from two Czech alder populations, one suffering from severe Phytophthora decline and the other disease-free. Results: The results showed significant differences in lesion development and seedling mortality. After a 13-week experimental period, at both CO2 levels P. x alni and P. uniformis showed high aggressiveness to A. glutinosa seedlings causing lesions of variable sizes and mortality of 33.3%, and 45.8% of plants, respectively. In contrast, P. plurivora did not cause mortality to any plant, and lesion sizes did not differ significantly from those in control plants. Physiological measurements did not reveal any significant differences between Phytophthora species except for plants inoculated with P. plurivora showing increased values in specific physiological parameters 4 weeks post-inoculation. Net photosynthesis decreased over the measurement period in all treatments with significant differences found between measurements conducted 2 and 4 weeks after the inoculation. Transpiration showed a decreasing trend in all inoculated plants with no significant differences between Phytophthora species at both CO2 levels. Chemical analyses of root samples showed high variability in sugars and phenolic compounds related to the plant's health status. Discussion: This is the first study to examine the response of alder seedlings to Phytophthora pathogens at different CO2 levels. The findings demonstrate high aggressiveness of P. x alni and P. uniformis and weaker aggressiveness of P. plurivora to alder seedlings regardless of the CO2 level.O
Bio-based phase change material for enhanced building energy efficiency: A study of beech and thermally modified beech wood for wall structures
Get PDFThis study investigated the impregnation of beech and thermally modified beech (TMB) with a ternary mixture of capric acid, palmitic acid, and stearic acid as a bio-based phase change material (BPCM). Finite element method (FEM) was used to complement the experimental analysis by providing new insights into computational methods for simulating the behavior of BPCMs in untreated and TMB. The analyzed specimens namely beech and TMB were impregnated with BPCM; the TMB achieved 54% weight percentage gain (WPG) while untreated beech got 37%. Accordingly, a greater increase in the latent heat was obtained for TMB up to 90 J/g, while for untreated beech with BPCM up to 75 J/g. Impregnated specimens absorbed less moisture at relative humidity of air above 50%, likely caused by the high uptake and hydrophobic nature of the BPCM. The study highlights the research gap in performing mathematical simulations on wood samples with BPCM using material thermal properties derived from differential scanning calorimetry or T-History analysis. It shows that the direct use of these values for simulations leads to unacceptable outputs that result in high errors. The root mean square error for untreated and TMB samples impregnated with BPCM was in the range from 1.06 to 3.1 while that for untreated samples was in the range from 0.57 to 0.87, indicating that the main challenge in simulating and characterizing the samples is due to the interaction of the phase change material with the wood structure.OA-hybri
Energy Potential of Urban Green Waste and the Possibility of Its Pelletization
Get PDFDue to ongoing changes in the European energy market, there is currently a need to find new and additional uses for waste materials. Horticultural waste, which has not yet been fully recognized, offers a relatively wide potential in this area. Although the properties of these wastes are not ideal for combustion, they can be used as a solid biofuel. The pellets that are produced, however, may have useful properties, either energetic or environmental, and are valuable when utilized in boilers. In this study, six examples of typical input raw materials were selected, analysed, and subsequently pelletized. The experimental results provided an overview of the physio-chemical properties of the evaluated samples. Specifically, the moisture content (9.2-27.8%), bulk density (131.4-242.8 kg.mMINUS SIGN 3 wt), ash content (3.0-28.0%), lower calorific value (11.3-16.2 MJ.kgMINUS SIGN 1), and major and minor elements, were evaluated. The pelletization process and resultant pellet characteristics, such as durability (96.3-98.8%), moisture content (7.5-11.5%), and dimensions, were also evaluated. In the statistical evaluation, significant differences were found between individual samples. In particular, both the branches and the mixture of perennial plants met the industry standard limits, showing that they are of sufficient quality. On the contrary, the sample of fallen leaves was particularly problematic with regard to a number of parameters (moisture, ash content, and calorific value). The overview of the analyses performed expands the current state of knowledge on the potential to use selected types of horticultural waste in the field of energy and for the production of shaped biofuels.O