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Heracleum mantegazzianum is an invasive species in middle Europe. The mode of action of its invasiveness is still not known. Our study focuses on observation of potential allelopathic influence by the production and release of phytochemicals into its environment. Plant material was collected four times within one season (April, May, June, July 2019) at locality Lekárovce (eastern Slovakia) for comparison of differences in composition and potential allelopathy. Water extracts from collected samples were used for different biological assays. The total phenols and flavonoids were determined spectrophotometrically. The profile and content of phenolic components, including coumarins, were determined by two techniques of liquid chromatography along with in vitro evaluation of the free radical scavenging activity of extracts (DPPH, Hydroxyl, Superoxide, and FRAP). The changes in composition in extracts in different seasonal periods were evident as well as potential phytotoxic activity in some concentrations on specific model plants. The slight antioxidant activity was noted. The invasiveness of the current species could be supported by the excretion of its phytochemicals into its surroundings and by different modes of action influencing living organisms in its environment.

High-entropy rare-earth (RE) zirconates with pyrochlore structure were successfully fabricated by pressureless and spark plasma sintering. RE2Zr2O7 compound with nominal composition (La0.2Y0.2Gd0.2Nd0.2Sm0.2)Zr2O7 was prepared by simple glycine nitrate procedure (GNP). GNP process yielded powders with low crystallinity and after subsequent calcination, well crystalline ceramics were formed. During calcination defective fluorite (F-RE2Zr2O7) and crystal pyrochlore (Py-RE2Zr2O7) structures coexist. Formation of pure crystalline pyrochlore occurs after sintering at 1450 °C. High-density ceramics, free of any additives, were obtained after powders compaction and pressureless (PS), as well as field assisted sintering technique (FAST) at 1450 °C. Theoretical investigations of the high-entropy RE2Zr2O7 pyrochlore systems were performed. Unit cell parameter of the obtained Py-RE2Zr2O7 is 10.5892(2) Å and 10.5999(2) Å for PS and FAST sintering, respectively, which is in good agreement with the results of Density Functional Theory (DFT) calculations. The thermal diffusivity of sintered samples at room temperature was ∼0.7 mm2/s for both sintering methods. Resumen: Se fabricaron con éxito, mediante sinterización por plasma sin presión y por chispa, los circonatos de tierras raras (RE) de alta entropía con estructura de pirocloro. El compuesto RE2Zr2O7 con composición nominal (La0,2Y0,2Gd0,2Nd0,2Sm0,2)Zr2O7 se preparó mediante un procedimiento simple de nitrato de glicina (GNP). El proceso GNP produjo polvos con baja cristalinidad y después de la posterior calcinación, se formaron cerámicas bien cristalinas. Durante la calcinación coexisten estructuras defectuosas de fluorita (F-RE2Zr2O7) y pirocloro cristalino (Py-RE2Zr2O7). La formación de pirocloro cristalino puro se produce después de la sinterización a 1.450 °C. Después de la compactación de polvos y sin presión (PS), así como por la técnica de sinterización asistida en campo (FAST) a 1.450 oC, se obtuvieron cerámicas de alta densidad, libres de aditivos. Se realizaron investigaciones teóricas de los sistemas de pirocloro RE2Zr2O7 de alta entropía. El parámetro de celda unitaria del Py-RE2Zr2O7 obtenido es 105.892(2) Å y 105.999(2) Å para la sinterización PS y FAST, respectivamente, lo que está de acuerdo con los resultados de los cálculos de la teoría funcional de la densidad (DFT). La difusividad térmica de las muestras sinterizadas a temperatura ambiente fue de ∼ 0,7 mm2/s para ambos métodos de sinterización.

Most of the video content on the Internet today is distributed through online streaming platforms. To ensure user privacy, data transmissions are often encrypted using cryptographic protocols. In previous research, we first experimentally validated the idea that the amount of transmitted data belonging to a particular video stream is not constant over time or that it changes periodically and forms a specific fingerprint. Based on the knowledge of the fingerprint of a specific video stream, this video stream can be subsequently identified. Over several months of intensive work, our team has created a large dataset containing a large number of video streams that were captured by network traffic probes during their playback by end users. The video streams were deliberately chosen to fall thematically into pre-selected categories. We selected two primary platforms for streaming - PeerTube and YouTube The first platform was chosen because of the possibility of modifying any streaming parameters, while the second one was chosen because it is used by many people worldwide. Our dataset can be used to create and train machine learning models or heuristic algorithms, allowing encrypted video stream identification according to their content resp. type category or specifically.

This mini review critically discusses self-assembled mesoscale structures (dimensions between molecular and macroscopic) forming in multicomponent mixtures comprising 1) liquids or 2) liquids and solids or 3) liquids and gases. The common feature of the discussed structures is absence of surfactants. Covered are solvophobicity-driven mesoscale structures (including metastable ouzo-type particles with finite lifetimes), surfactant-free microemulsions, and bulk nanobubbles. The emphasis is mainly on critical analysis of experimental data and suitability of available experimental methods with focus on unambiguous differentiation between various types of mesoscale structures.

This work reports about preparation of W/Fe co-sputtered layers between tungsten and steel in order to ease their coefficient of thermal expansion mismatch.Iron and tungsten have been gradually co-sputtered on W tiles with real time deposition parameters changing to obtain a graded interlayer: SEM, EDS, XPS, HR-TEM have been used to characterize the W/Fe co-sputtered layer.W tiles co-sputtered with the W/Fe layers have been hot pressed to steel tiles: morphology and mechanical strength have been investigated for joints with and without W/Fe co-sputtered layer.Lap-shear tests in compression at room temperature have been made on hot pressed W/steel joints with and without W/Fe co-sputtered layer, showing a different behaviour.High flux test on joints with and without W/Fe co-sputtered layer are reported and discussed. The mechanical test results of manufactured joints are in good accordance with high heat flux test results, showing that the behaviour of hot-pressed joints with W/Fe co-sputtered layer was slightly worse if compared to joints without co-sputtered layer at the interface.

Quantum instruments describe outcome probability as well as state change induced by measurement of a quantum system. Incompatibility of two instruments, i. e. the impossibility to realize them simultaneously on a given quantum system, generalizes incompatibility of channels and incompatibility of positive operator-valued measures (POVMs). We derive implications of instrument compatibility for the induced POVMs and channels. We also study relation of instrument compatibility to the concept of non-disturbance. Finally, we prove equivalence between instrument compatibility and postprocessing of certain instruments, which we term complementary instruments. We illustrate our findings on examples of various classes of instruments.

In 2022/2023, Europe experienced its third consecutive season of high-pathogenicity avian influenza. During this period, the Czech Republic was again severely affected. For the first time, the number of culled birds approached one million, which was three times higher than in previous seasons. In parallel to the outbreaks in poultry, mass die-offs of gulls were also observed. In the present study, we performed whole-genome sequencing and phylogenetic analysis of 137 H5N1 strains collected in the Czech Republic in 2022/2023 (94.6% of all outbreaks or locations). The analysis revealed four distinct genotypes: AB, CH, BB and AF. Phylogenetic analysis suggested that the AF genotype persisted from the previous H5N1 season without reassortment. In addition, the genotype BB, which was detected mainly in gulls, showed a noticeable strain diversity at the local level. This virus was also responsible for a single outbreak in commercially bred turkeys. Finally, an interesting spatio-temporal cluster with three co-circulating H5N1 genotypes, AB, CH and AF, was identified with no evidence of intrasubtype reassortment. Highly sensitive molecular surveillance and the timely sharing of genomic sequences and associated metadata could greatly assist in tracking the spread and detecting molecular changes associated with the increased virulence of this potentially zoonotic pathogen.

Alumina (Al2O3) ceramics are interesting for low-weight and mid-high temperature applications. The addition of indium (In) and graphene nanoplatelets (GNPs) can be used to reduce the density and modify the functional properties and mechanical performance of the ceramic matrix. GNP and In-reinforced Al2O3 matrix composites were prepared by the spark plasma sintering (SPS) technique. Monolithic Al2O3 and Al2O3 matrix composites with either 5 or 10 wt.% of In and 2 wt.% of GNPs (Al2O3-5In-2GNPs and Al2O3-10In-2GNPs) were compacted into disc-shaped samples. The microstructure was studied and characterized with light-optical microscopy (LOM) and scanning electron microscopy (SEM). Hardness was determined using the Vickers technique and tribological properties were studied by the ball-on-disk method. The coefficient of friction (COF) and specific wear rates were evaluated from tribological tests. Worn surfaces were studied by SEM and confocal microscopy. Interdiffusion transition regions were formed among individual microstructural constituents (Al2O3, In, GNPs) under high sintering temperatures, which were responsible for the balanced hardness and low porosity of the produced composites. The addition of In and graphene nanoplatelets resulted in smaller COF and wear rates indicating good improvement in the tribological behavior. The prepared Al2O3-5In-2GNP and Al2O3-10In-2GNP composites represent promising nanocomposites for self-lubricating applications.

Research infrastructures play a key role in launching a new generation of integrated long-Term, geographically distributed observation programmes designed to monitor climate change, better understand its impacts on global ecosystems, and evaluate possible mitigation and adaptation strategies. The pan-European Integrated Carbon Observation System combines carbon and greenhouse gas (GHG; CO 2 , CH 4 , N 2 O, H 2 O) observations within the atmosphere, terrestrial ecosystems and oceans. High-precision measurements are obtained using standardised methodologies, are centrally processed and openly available in a traceable and verifiable fashion in combination with detailed metadata. The Integrated Carbon Observation System ecosystem station network aims to sample climate and land-cover variability across Europe. In addition to GHG flux measurements, a large set of complementary data (including management practices, vegetation and soil characteristics) is collected to support the interpretation, spatial upscaling and modelling of observed ecosystem carbon and GHG dynamics. The applied sampling design was developed and formulated in protocols by the scientific community, representing a trade-off between an ideal dataset and practical feasibility. The use of open-Access, high-quality and multi-level data products by different user communities is crucial for the Integrated Carbon Observation System in order to achieve its scientific potential and societal value.

Introduction Severe asthma is a complex, multidimensional disease. Optimal treatment, adherence and outcomes require shared decision-making, rooted in mutual understanding between patient and clinician. This study used a novel, patient-centred approach to examine the most bothersome aspects of severe asthma to patients, as seen from both perspectives in asthma registries. Methods Across seven countries, 126 patients with severe asthma completed an open-ended survey regarding most the bothersome aspect(s) of their asthma. Patients’ responses were linked with their treating clinician who also completed a free-text survey about each patient's most bothersome aspect(s). Responses were coded using content analysis, and patient and clinician responses were compared. Finally, asthma registries that are part of the SHARP (Severe Heterogeneous Asthma Research collaboration, Patient-centred) Clinical Research Collaboration were examined to see the extent to which they reflected the most bothersome aspects reported by patients. Results 88 codes and 10 themes were identified. Clinicians were more focused on direct physical symptoms and were less focused on “holistic” aspects such as the effort required to self-manage the disease. Clinicians accurately identified a most bothersome symptom for 29% of patients. Agreement was particularly low with younger patients and those using oral corticosteroids infrequently. In asthma registries, patient aspects were predominantly represented in questionnaires. Conclusions Results demonstrated different perspectives and priorities between patients and clinicians, with clinicians more focused on physical aspects. These differences must be considered when treating individual patients, and within multidisciplinary treatment teams. The use of questionnaires that include multifaceted aspects of disease may result in improved asthma research.

Raspberry plants, valued for their fruits, are vulnerable to a range of viruses that adversely affect their yield and quality. Utilizing high-throughput sequencing (HTS), we identified a novel virus, tentatively named raspberry enamovirus 1 (RaEV1), in three distinct raspberry plants. This study provides a comprehensive characterization of RaEV1, focusing on its genomic structure, phylogeny, and possible transmission routes. Analysis of nearly complete genomes from 14 RaEV1 isolates highlighted regions of variance, particularly marked by indel events. The evidence from phylogenetic and sequence analyses supports the classification of RaEV1 as a distinct species within the Enamovirus genus. Among the 289 plant and 168 invertebrate samples analyzed, RaEV1 was detected in 10.4% and 0.4%, respectively. Most detections occurred in plants that were also infected with other common raspberry viruses. The virus was present in both commercial and wild raspberries, indicating the potential of wild plants to act as viral reservoirs. Experiments involving aphids as potential vectors demonstrated their ability to acquire RaEV1 but not to successfully transmit it to plants.

Apple proliferation, caused by ‘Candidatus Phytoplasma mali’, is one of the most important economic threats in the field of apple production. Especially at a young age, infected trees can be affected by excessive bud proliferation and general decline. The fruit quality is also significantly reduced by this disease. To investigate treatment options, we applied a clarithromycin chemotherapy to infected in vitro cultures of ‘Golden Delicious’. With increasing concentrations of clarithromycin in the media, the phytoplasma load decreased rapidly after one month of treatment, but phytotoxicity led to a pronounced mortality at 40 mg/L, which was the highest dose used in our experiment. Out of 45 initial explants, we obtained one negative mericlone and two mericlones with a concentration of phytoplasma DNA at the detection limit of PCR. The culture propagated from the mericlone that tested negative remained phytoplasma-free after 18 months of subculturing. Our results suggest the applicability of macrolide antibiotics against phytoplasma infections in vitro; however, it might be challenging to find the threshold zone where the concentration is sufficient for pathogen elimination, but not lethal for the plant material of different cultivars.

Severe plastic deformation of commercially pure titanium, leading to ultrafine-grained microstructure, can be used as an alternative to alloying to obtain better mechanical properties without the reduction of biocompatibility and corrosion resistance. However, the strong texture, induced by plastic deformation, results in anisotropy of mechanical properties, understanding of which is crucial to design and model perspective structural parts and devices. In this work, ultrafine-grained grade 2 Ti, obtained by equal channel angular pressing, is investigated. A detailed study of the texture and the elastic anisotropy of the material, heat-treated at several annealing temperatures, is conducted, complemented by ex-situ and indirect in-situ thermal experiments, which shed light on the stability and evolution of microstructure and material properties. The results show that the elastic properties only slightly evolve during annealing in contrast to other properties, such as thermal expansion, internal friction or hardness. The elastic anisotropy is directly linked to the (0001) texture, thus outlining the importance and possibilities of texture-based design and tailoring of mechanical properties.

Apple hammerhead viroid (AHVd) was detected in the apple cultivar ‘Šampion’ and in mixed infection with Solanum nigrum ilarvirus 1 (SnIV-1) in the cultivars ‘Selena’ and ‘Jonagored Supra’, using a high-throughput sequencing method. Experiments were conducted to eliminate both pathogens in apples using meristem tip cultures in combination with the antivirotics ribavirin, rimantadine, and zidovudine. Elimination of both pathogens was verified by repeated RT-PCR and qRT-PCR assays after 7–11 months. Elimination of SnIV-1 from all cultivars was successful with each of the three antivirotics at concentrations of 20, 40, and 80 mg L−1. Elimination of AHVd was also achieved, although less effectively and only with ribavirin in the concentration range of 20–160 mg L−1.

Lyme disease, caused by some strains of bacterial spirochetes Borrelia burgdorferi sensu lato (Bbsl), affects humans but also domestic animals including horses. The primary pathogens in horses in Europe are B. afzelii, B. garinii and B. burgdorferi sensu stricto. To our knowledge, there are no data available on the seropositivity of B. burgdorferi s.l. in horses from the Czech Republic. In this country, horses are mainly used for sport, breeding, and recreational riding in areas where vectors of B. burgdorferi s.l. are present, which is why they are frequently at risk of infection. The aim of the study was to detect anti-borrelia IgM and IgG antibodies in clinically healthy and sick horses from the Czech Republic and to evaluate the risk factors of infection. In total, sera of 262 horses (247 clinically healthy horses and 15 horses hospitalized due to symptoms of encephalitis/meningoencephalitis) were examined by an indirect sandwich enzyme-linked immunosorbent assay. Positivity of B. burgdorferi was 27% (66/247) in clinically healthy horses (21% IgM, 7% IgG and 3% IgM + IgG antibodies) and 20% (3/15) in horses with clinical signs (20% IgM, 7% IgG and 7% IgM + IgG). In the clinically healthy horses, positivity statistically differed (p ≤ 0.05) only in Pony and Warmblood breeds, being the most affected at 32% and 30%, respectively, while other characteristics (sex, age, usage and localities) had no effect on positivity. This is the first survey of antibodies to B. burgdorferi s.l. in Czech horses showing that horses are exposed to ticks infected with B. burgdorferi s.l. This should be taken into account when making differential diagnoses in patients with non-specific symptoms to start with adequate therapy.

Proof of concept salt tolerance and plasticity. Wild germplasm may represent a precious source of genetic variability for salt tolerance. This study evaluated the morphological changes occurring under controlled and saline conditions in tuber-bearing S. bulbocastanum, S. commersonii, S. chomatophyllum, S. multidissectum, S. pinnactisectum, S. phureja, and cultivated S. tuberosum. An in vitro screening method was employed. Significant phenotypic variations were observed for all phenotypic traits analyzed at all NaCl levels (0, 40, 60, and 120 mM). In addition, a significant correlation between root plasticity and salt tolerance was found. Further, changes in proline and total phenolic content were assessed to envisage the metabolic adjustments of tolerant clones towards salinity. The most promising sources of tolerance were identified in S. commersonii and S. multidissectum and information obtained is discussed from a breeding perspective.

Systemic infections with phytoplasmas and viruses threaten the production of healthy plant material under the fruit species certification system. We tested the possibility of sanitation using in vitro culture and cryotherapy. The starting material of the cultivars Golden Delicious (clones A and B), Virginia Crab, and Panenské zlepšené was taken from in vivo plants that tested positive for apple proliferation phytoplasma. The Táborita cultivar was obtained from already established in vitro cultures that had tested positive for apple proliferation phytoplasma, apple mosaic virus, and apple chlorotic leaf spot virus. Cultivars Golden Delicious A, Virginia Crab, and Panenské zlepšené were sanitated from the phytoplasma in the first step, i.e., by sterilization and a subsequent transfer to in vitro conditions. Golden Delicious B remained infected with the phytoplasma, and both viruses, after the in vitro culture phase and together with Táborita, were subjected to cryotherapy by vitrification. In Golden Delicious B, three out of thirteen initial shoot tips regenerated after a liquid nitrogen treatment. Four mericlones were regenerated from 10 initial cryopreserved shoot tips of Táborita. None of the three pathogens were detected by PCR in the regenerated Golden Delicious B mericlones. On the contrary, in the case of Táborita, infection with all the pathogens was detected after regeneration. The results obtained indicate the potential applicability of in vitro cultivation techniques or, if necessary, subsequent cryopreservation as a method for sanitizing against systemic microbial contamination. However, further research on the relationship between pathogens and specific genotypes is needed.