The present investigation provides an easy and affordable strategy for fabrication of functional ceramics Bi0.5Na0.5TiO3-SrFe12O19 (BNT-SrF5) thick films on a flexible, inexpensive and electrically integrated substrate using electrophoretic deposition process (EPD). EPD is a widely accepted, environmentally friendly method for applying coatings from a colloidal suspension to conductive substrates. Lead-free ferroelectric BNT-SrF5 powder was synthesized by solid state method to fabricate bulk samples and thick films (30-160 μm) by EPD process. Thick films were deposited onto nickel substrate by applying EPD parameters, i.e. voltage (225-290 V) and coating time (30-180 s) to acetone based colloidal suspension without aid of any dispersing agent. In a comparative analysis, both thick films and bulk ceramics revealed significant densification with sintering temperature from 1025 to 1150 °C. Fourier transform Infrared (FTIR) and X-ray diffraction (XRD) analysis revealed presence of distorted perovskite structure following calcination and sintering processes. Scanning electron microscopy (SEM) provided the surface morphologies of BNT-SrF5 powder. The dielectric constant of film sample revealed more thermal stable response compared to the bulk ceramics. Impedance spectroscopy explained the electrically active regions and hopping conduction mechanism which witnessed NTCR behavior. The potential applications for the miniaturization of electronics are sensors, actuators and energy harvesting devices.

• Klíčová slova
• Bulk, Energy, Film, Flexible, Suspension,
• Publikační typ
• časopisecké články MeSH

Reverse transcription quantitative PCR (RT-qPCR) is already an established tool for mRNA detection and quantification. Since recently, this technique has been successfully employed for gene expression analyses, and also in individual cells (single cell RT-qPCR). Although the advantages of single cell measurements have been proven several times, a study correlating the expression measured on single cells, and in bulk samples consisting of a large number of cells, has been missing. Here, we collected a large data set to explore the relation between gene expression measured in single cells and in bulk samples, reflected by qPCR Cq values. We measured the expression of 95 genes in 12 bulk samples, each containing thousands of astrocytes, and also in 693 individual astrocytes. Combining the data, we described the relation between Cq values measured in bulk samples with either the percentage of the single cells that express the given genes, or the average expression of the genes across the single cells. We show that data obtained with single cell RT-qPCR are fully consistent with measurements in bulk samples. Our results further provide a base for quality control in single cell expression profiling, and bring new insights into the biological process of cellular expression.

• MeSH
• analýza jednotlivých buněk * MeSH
• gliový fibrilární kyselý protein genetika   MeSH
• messenger RNA genetika   MeSH
• myši transgenní MeSH
• myši MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• stanovení celkové genové exprese * MeSH
• zelené fluorescenční proteiny genetika   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• enhanced green fluorescent protein MeSH Prohlížeč
• gliový fibrilární kyselý protein MeSH
• messenger RNA MeSH
• zelené fluorescenční proteiny MeSH

Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are ubiquitous and toxic contaminants. Their atmospheric deposition fluxes on the regional scale were quantified based on simultaneous sampling during 1 to 5 years at 1 to 6 background/rural sites in the Czech Republic and Austria. The samples were extracted and analysed by means of gas chromatography coupled to mass spectrometry. For all seasons and sites, total deposition fluxes for Σ15PAHs ranged 23-1100 ng m-2 d-1, while those for Σ6PCBs and Σ12OCPs ranged 64-4400 and 410-7800 pg m-2 d-1, respectively. Fluoranthene and pyrene were the main contributors to the PAH deposition fluxes, accounting on average for 19% each, while deposition fluxes of PCBs and OCPs were dominated by PCB153 (26%) and γ-hexachlorobenzene (30%), respectively. The highest deposition flux of Σ15PAHs was generally found in spring, while no seasonality was found for PCB deposition. For deposition fluxes for Σ12OCPs, no clear spatial trend was found, confirming the perception of long-lived regional pollutants. Although most OCPs and PCBs hardly partition to the particulate phase in ambient air, on average, 42% of their deposition fluxes were found on filters, confirming the perception that particle deposition is more efficient than dry gaseous deposition. Due to methodological constraints, fluxes derived from bulk deposition samplers should be understood as lower estimates, in particular with regard to those substances which in ambient aerosols mostly partition to the particulate phase.

• Klíčová slova
• Bulk atmospheric deposition, Central Europe, Deposition fluxes, OCPs, PAHs, PCBs, POPs,
• MeSH
• chlorované uhlovodíky analýza   MeSH
• hexachlorbenzen analýza   MeSH
• látky znečišťující vzduch analýza   MeSH
• monitorování životního prostředí * MeSH
• pesticidy analýza   MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• polychlorované bifenyly analýza   MeSH
• polycyklické aromatické uhlovodíky analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Evropa MeSH
• Rakousko MeSH
• Názvy látek
• chlorované uhlovodíky MeSH
• hexachlorbenzen MeSH
• látky znečišťující vzduch MeSH
• pesticidy MeSH
• polychlorované bifenyly MeSH
• polycyklické aromatické uhlovodíky MeSH

Coxiella burnetii is the aetiological agent of Q fever, which is highly prevalent in Turkiye, but information on the genetic profiles of the bacterium is limited. This study aimed to investigate the presence of C. burnetii in bovine bulk tank milk (BTM) samples by polymerase chain reaction (PCR) and to investigate the genotypes by means of multiple-locus variable-number tandem repeat analysis (MLVA). A total of 25 markets that sold raw cow's milk were analysed by conventional PCR analysis. An MLVA analysis was performed at six loci, namely MS23, MS24, MS27, MS28, MS33, and MS34, to determine the genotypic variations of C. burnetii found in the positive DNA samples. The DNA of C. burnetii was detected in 16% of the BTM samples. The C. burnetii strains identified in the bovine milk samples collected in this study were found to belong to the same genotypic group as those detected in the bovine milk samples gathered in Greece. As a result, both the presence and genotyping studies of C. burnetii on the BTM samples in Turkiye will contribute to the determination of the geographical distribution of the agent.

• Klíčová slova
• Q fever, Turkiye, genotyping, raw milk,
• Publikační typ
• časopisecké články MeSH

The purpose of this study was to examine the effect of oven and vacuum pretreatment techniques at drying temperatures between 40 °C and 90 °C and a constant heating time of 60 min on the oil yield, energy output, and compressive stress of bulk flax and hemp oilseeds samples. The results showed that heating temperatures linearly increased the amounts of oil yield but did not correlate linearly with energy requirement. The oven pretreatment slightly increased the oil yield and energy compared to the vacuum pretreatment. Higher compressive stress values were observed for hemp oilseeds than flax oilseeds which could be attributed to the inherent structure of the oilseeds. Hemp oilseeds showed more toughness to compress than flax oilseeds which tend to have a softer texture. The lack-of-fit p-values > 0.05 of the linear regression models dependent on the heating temperature under both drying conditions indicate adequacy for predicting the calculated parameters. Tukey's significance test showed that the means of oil yield and energy of bulk flax and hemp oilseeds under the oven and vacuum pretreatments revealed no significant difference implying that both pretreatment methods can initiate the same heat treatment effect on oil extraction efficiency with the corresponding energy requirement.

• Klíčová slova
• drying temperatures, heating methods, linear compression, oilseeds, regression models,
• Publikační typ
• časopisecké články MeSH

In this work, a new rapid method for the determination of 135 pesticide residues in green and black dry tea leaves and stalks employing gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) with a triple quadrupole was developed and validated. A substantial simplification of sample processing prior to the quantification step was achieved: after addition of water to a homogenised sample, transfer of analytes into an acetonitrile layer was aided by the addition of inorganic salts. Bulk co-extracts, contained in the crude organic extract obtained by partition, were subsequently removed by liquid-liquid extraction using hexane with the assistance of added 20% (w/w) aqueous NaCl solution. The importance of matrix hydration prior to the extraction for achieving good recoveries was demonstrated on tea samples with incurred pesticide residues. For most of the analytes, recoveries in the acceptable range of 70-120% and repeatabilities (relative standard deviations, RSDs) ≤20% were achieved for both matrices at spiking levels of 0.01, 0.1 and 1 mg kg(-1). Under optimised GC-MS/MS conditions, most of the analytes gave lowest calibration level ≤0.01 mg kg(-1), permitting the control at the maximum residue levels (MRLs) laid down in Regulation (EC) No 396/2005. The developed method was successfully applied to the determination of pesticide residues in real tea samples.

• MeSH
• čaj chemie   MeSH
• chemické techniky analytické * MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí * MeSH
• rezidua pesticidů analýza   MeSH
• tandemová hmotnostní spektrometrie * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• validační studie MeSH
• Názvy látek
• čaj MeSH
• rezidua pesticidů MeSH

In spite of the growth of molecular ecology, systematics and next-generation sequencing, the discovery and analysis of diversity is not currently integrated with building the tree-of-life. Tropical arthropod ecologists are well placed to accelerate this process if all specimens obtained through mass-trapping, many of which will be new species, could be incorporated routinely into phylogeny reconstruction. Here we test a shotgun sequencing approach, whereby mitochondrial genomes are assembled from complex ecological mixtures through mitochondrial metagenomics, and demonstrate how the approach overcomes many of the taxonomic impediments to the study of biodiversity. DNA from approximately 500 beetle specimens, originating from a single rainforest canopy fogging sample from Borneo, was pooled and shotgun sequenced, followed by de novo assembly of complete and partial mitogenomes for 175 species. The phylogenetic tree obtained from this local sample was highly similar to that from existing mitogenomes selected for global coverage of major lineages of Coleoptera. When all sequences were combined only minor topological changes were induced against this reference set, indicating an increasingly stable estimate of coleopteran phylogeny, while the ecological sample expanded the tip-level representation of several lineages. Robust trees generated from ecological samples now enable an evolutionary framework for ecology. Meanwhile, the inclusion of uncharacterized samples in the tree-of-life rapidly expands taxon and biogeographic representation of lineages without morphological identification. Mitogenomes from shotgun sequencing of unsorted environmental samples and their associated metadata, placed robustly into the phylogenetic tree, constitute novel DNA "superbarcodes" for testing hypotheses regarding global patterns of diversity.

• Klíčová slova
• Coleoptera, Illumina MiSeq, biodiversity, bulk samples, community ecology, metagenome skimming, mitochondrial genomes, mitochondrial metagenomics, phylogeny, tree-of-life,
• MeSH
• brouci genetika   MeSH
• deštný prales MeSH
• frekvence genu MeSH
• fylogeneze MeSH
• genetická variace MeSH
• genom mitochondriální MeSH
• hmyzí geny MeSH
• kontigové mapování MeSH
• metagenom MeSH
• mitochondrie genetika   MeSH
• sekvenční analýza DNA MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Borneo MeSH

Rapid analytical methods can contribute to the expansion of milk fatty acid determination for various important practical purposes. The reliability of data resulting from these routine methods plays a crucial role. Bulk and individual milk samples (60 and 345, respectively) were obtained from Czech Fleckvieh and Holstein dairy cows in the Czech Republic. The correlation between milk fatty acid (FA) proportions determined by the routine method (infrared spectroscopy in the mid-region in connection with Fourier transformation; FT-MIR) and the reference method (gas chromatography; GC) was evaluated. To validate the calibration of the FT-MIR method, a linear regression model was used. For bulk milk samples, the correlation coefficients between these methods were higher for the saturated (SFAs) and unsaturated FAs (UFAs) (r = 0.7169 and 0.9232; p < 0.001) than for the trans isomers of UFAs (TFAs) and polyunsaturated FAs (PUFAs) (r = 0.5706 and 0.6278; p < 0.001). Similar results were found for individual milk samples: r = 0.8592 and 0.8666 (p < 0.001) for SFAs and UFAs, 0.1690 (p < 0.01) for TFAs, and 0.3314 (p < 0.001) for PUFAs. The correlation coefficients for TFAs and PUFAs were statistically significant but too low for practical analytical application. The results indicate that the FT-MIR method can be used for routine determination mainly for SFAs and UFAs.

• Klíčová slova
• Czech Fleckvieh, Holstein, correlation coefficient, dairy cow, fatty acids, gas chromatography, mid-infrared spectroscopy, raw milk, regression analysis,
• Publikační typ
• časopisecké články MeSH

Estrone (E1), estradiols (α/β-E2), and estriol (E3) are four major metabolically active estrogens exerting strong biological activities at very low circulating concentrations. This paper reports a sensitive and efficient method with automated, on-line clean-up and detection to determine trace estrogens in a small volume of serum samples using liquid chromatography-electrospray ionization-tandem mass spectrometry directly, without off-line liquid-liquid or solid-phase extraction pretreatments. Serum aliquots (charcoal stripped fetal bovine serum, 100 μL) were spiked with four estrogen standards and their corresponding isotope-labeled internal standards, then bulk derivatized with 2-fluoro-1-methyl-pyridium p-toluenesulfonate (2-FMP) to establish the calibration curves and perform method validation. Calibration was established in the concentration ranges of 5-1000 pg mL(-1), and demonstrated good linearity of R(2) from 0.9944 to 0.9997 for the four derivatized estrogens. The lower detection limits obtained were 3-7 pg mL(-1). Good accuracy and precision in the range of 86-112% and 2.3-11.9%, respectively, were observed for the quality control (QC) samples at low, medium, and high concentration levels. The stability tests showed that the derivatized serum samples were stable 8h after derivatization at room temperature and at least to 48 h if stored at -20 °C. The method was applied to measure trace estrogens in real human and bovine serum samples, and three of four estrogen compounds studied were observed and quantified.

• Klíčová slova
• Charged bulk derivatization, Electrospray ionization, Estrogen, Quantitative analysis, Restricted access media, Weak cation exchange,
• MeSH
• chromatografie kapalinová metody   MeSH
• estrogeny krev   chemie   MeSH
• extrakce na pevné fázi MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací metody   MeSH
• indikátory a reagencie MeSH
• kalibrace MeSH
• kationtoměniče MeSH
• lidé MeSH
• limita detekce MeSH
• reprodukovatelnost výsledků MeSH
• skot MeSH
• tandemová hmotnostní spektrometrie metody   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• estrogeny MeSH
• indikátory a reagencie MeSH
• kationtoměniče MeSH

The main aim of the study was to analyse the strain rate sensitivity of the compressive deformation response in bulk 3D-printed samples from 316L stainless steel according to the printing orientation. The laser powder bed fusion (LPBF) method of metal additive manufacturing was utilised for the production of the samples with three different printing orientations: 0∘, 45∘, and 90∘. The specimens were experimentally investigated during uni-axial quasi-static and dynamic loading. A split Hopkinson pressure bar (SHPB) apparatus was used for the dynamic experiments. The experiments were observed using a high-resolution (quasi-static loading) or a high-speed visible-light camera and a high-speed thermographic camera (dynamic loading) to allow for the quantitative and qualitative analysis of the deformation processes. Digital image correlation (DIC) software was used for the evaluation of displacement fields. To assess the deformation behaviour of the 3D-printed bulk samples and strain rate related properties, an analysis of the true stress-true strain diagrams from quasi-static and dynamic experiments as well as the thermograms captured during the dynamic loading was performed. The results revealed a strong strain rate effect on the mechanical response of the investigated material. Furthermore, a dependency of the strain-rate sensitivity on the printing orientation was identified.

• Klíčová slova
• 316L stainless steel, 3D printing, laser powder bed fusion, printing direction, split Hopkinson pressure bar,
• Publikační typ
• časopisecké články MeSH