Coccolith dissolution together with post-mortem morphological features are immensely important phenomena that can affect assemblage compositions, complicate taxonomic identification as well as provide valuable palaeoenvironmental insights. This study summarizes the effects of pH oscillations on post-mortem coccolith morphologies and the abundances and compositions of calcareous nannoplankton assemblages in three distinct types of material-(i) Cretaceous chalk, (ii) Miocene marls, and (iii) late Holocene calcareous ooze. Two independent experimental runs within a semi-enclosed system setting were realized to observe assemblage alterations. One experiment was realized with the presence of bacteria and, in contrast, the second one inhibited their potential effect on the studied system. The pH was gradually decreased within the range of 8.3-6.4 using a reaction of CO2 with H2 O forming weak carbonic acid (H2 CO3 ), thereby affecting [ CO 3 2 - ]. Further, a subsequent overgrowth study was carried out during spontaneous degassing accompanied by a gradual pH rise. The experiment revealed that the process and intensity of coccolith corrosion and subsequent overgrowth build-ups are influenced by a plethora of different factors such as (i) pH and associated seawater chemistry, (ii) mineral composition of the sediment, (iii) the presence of coccoliths within a protective substrate (faecal pellets, pores, pits), and (iv) the presence/absence of bacteria. Nannoplankton assemblages with corroded coccoliths or with coccoliths with overgrowth build-ups showed that the observed relative abundances of taxa experienced alteration from the original compositions. Additionally, extreme pH oscillations may result in enhanced morphological changes that make coccoliths unidentifiable structures, and might even evoke the absence of coccoliths in the fossil record.
- Klíčová slova
- coccolith abundance, coccolith corrosion, coccolith overgrowths, dissolution-resistant taxa, pH fluctuations,
- MeSH
- Haptophyta * MeSH
- mořská voda chemie MeSH
- rozpustnost MeSH
- uhličitan vápenatý * chemie MeSH
- zkameněliny MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- uhličitan vápenatý * MeSH
Ferrous slag produced by a historic smelter is washed from a slagheap and transported by a creek through a cave system. Slag filling cave spaces, abrasion of cave walls / calcite speleothems, and contamination of the aquatic environment with heavy metals and other toxic components are concerns. We characterize the slag in its deposition site, map its transport through the cave system, characterize the effect of slag transport, and evaluate the risks to both cave and aqueous environments. The study was based on chemical and phase analysis supported laboratory experiments and geochemical modeling. The slag in the slagheap was dominated by amorphous glass phase (66 to 99 wt%) with mean composition of 49.8 ± 2.8 wt% SiO2, 29.9 ± 1.6 wt% CaO, 13.4 ± 1.2 wt% Al2O3, 2.7 ± 0.3 wt% K2O, and 1.2 ± 0.1 wt% MgO. Minerals such as melilite, plagioclase, anorthite, and wollastonite / pseudowollastonite with lower amounts of quartz, cristobalite, and calcite were detected. Slag enriches the cave environment with Se, As, W, Y, U, Be, Cs, Sc, Cd, Hf, Ba, Th, Cr, Zr, Zn, and V. However, only Zr, V, Co, and As exceed the specified limits for soils (US EPA and EU limits). The dissolution lifetime of a 1 mm3 volume of slag was estimated to be 27,000 years, whereas the mean residence time of the slag in the cave is much shorter, defined by a flood frequency of ca. 47 years. Consequently, the extent of slag weathering and contamination of cave environment by slag weathering products is small under given conditions. However, slag enriched in U and Th can increase radon production as a result of alpha decay. The slag has an abrasive effect on surrounding rocks and disintegrated slag can contaminate calcite speleothems.
- Klíčová slova
- Environmental risk, Experimental abrasion, Ferrous slag, Pollutant release, Rudice Sink – Býčí skála Cave System, Slag transport/weathering,
- MeSH
- kadmium analýza MeSH
- křemen analýza MeSH
- minerály analýza MeSH
- oxid hořečnatý analýza MeSH
- oxid křemičitý analýza MeSH
- půda MeSH
- radon * analýza MeSH
- silikáty MeSH
- sloučeniny vápníku MeSH
- těžké kovy * analýza MeSH
- uhličitan vápenatý analýza MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- calcium silicate MeSH Prohlížeč
- kadmium MeSH
- křemen MeSH
- minerály MeSH
- oxid hořečnatý MeSH
- oxid křemičitý MeSH
- půda MeSH
- radon * MeSH
- silikáty MeSH
- sloučeniny vápníku MeSH
- těžké kovy * MeSH
- uhličitan vápenatý MeSH
The present study investigates the physicochemical properties and stability of a novel lipid-based formulation-surfactant-enriched oil marbles containing abiraterone acetate. While the biopharmaceutical performance of this formulation has been reported recently, this study aims to fill the gap between a promising in vivo performance and industrial applicability. A series of techniques were employed to assess the solid-state characteristics of oil marble cores along with their physicochemical properties upon stability testing. The chemical stability of abiraterone acetate in the formulation was also investigated. The core of the formulation was found to be stable both physically and chemically over 12 months of storage. The in vitro performance of stressed samples was evaluated using a dissolution experiment. The formulation has successfully self-emulsified upon incubation in bio-relevant media, resulting in a fast and complete API release. An important issue connected with the excipient used as a covering material of oil marbles has been identified. The seemingly insignificant water sorption caused agglomeration of the oil marbles and consequently compromised the dissolution rate in some of the stressed samples. Replacing HPMC with lactose as a covering material resulted in more favorable properties upon storage. Overall, it has been shown that oil marbles are an industrially applicable concept of the solidified lipid-based formulation.
- Klíčová slova
- SMEDDS formulation, capsule filling, liquid marbles, solidification, stability,
- MeSH
- abirateron MeSH
- biologické přípravky * MeSH
- chemie farmaceutická metody MeSH
- laktosa MeSH
- lipidy chemie MeSH
- pomocné látky * chemie MeSH
- povrchově aktivní látky chemie MeSH
- rozpustnost MeSH
- stabilita léku MeSH
- uhličitan vápenatý MeSH
- voda MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- abirateron MeSH
- biologické přípravky * MeSH
- laktosa MeSH
- lipidy MeSH
- pomocné látky * MeSH
- povrchově aktivní látky MeSH
- uhličitan vápenatý MeSH
- voda MeSH
Current artificial soils for ecotoxicological studies contain non-renewable materials that must be mined, and their production and processing consume a lot of energy and generate a significant amount of carbon dioxide (CO2). In this paper, waste brick dust is proposed as an alternative to calcium carbonate (CaCO3), which is used for pH adjustment of the Organization for Economic Co-operation and Development (OECD) soils. The artificial soils containing brick dust are contaminated with boric acid as a reference substance in the concentration range of 100-500 mg/kg and studied in the tests with enchytraeids (E. crypticus), springtails (F. candida), and plants (L. sativa and B. napus). Experimental results shows the suitability of replacing calcium carbonate with waste brick dust, as neither toxicity nor ability of model organisms to inhabit the analyzed soil is found. A comparison with the standard OECD soil does not reveal any substantial differences between the parameters (survival, reproduction, and root elongation) of the applied ecotoxicological tests. The brick dust as waste material is found to have a lower carbon footprint than CaCO3, while a similar amount of water is necessary for the adjustment of tests with both kinds of artificial soil. The waste brick dust can be considered as a suitable eco-friendly alternative to CaCO3 in artificial soils for ecotoxicological studies.
- Klíčová slova
- Artificial soil, Calcium carbonate, Ecotoxicity, Invertebrates, Plants, Waste brick dust,
- MeSH
- členovci * MeSH
- látky znečišťující půdu * analýza MeSH
- Oligochaeta * MeSH
- oxid uhličitý MeSH
- prach MeSH
- prospektivní studie MeSH
- půda chemie MeSH
- rozmnožování MeSH
- uhličitan vápenatý MeSH
- voda MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- látky znečišťující půdu * MeSH
- oxid uhličitý MeSH
- prach MeSH
- půda MeSH
- uhličitan vápenatý MeSH
- voda MeSH
Actinobacteria are important cave inhabitants, but knowledge of how anthropization and anthropization-related visual marks affect this community on cave walls is lacking. We compared Actinobacteria communities among four French limestone caves (Mouflon, Reille, Rouffignac, and Lascaux) ranging from pristine to anthropized, and within Lascaux Cave between marked (wall visual marks) and unmarked areas in different rooms (Sas-1, Passage, Apse, and Diaclase). In addition to the 16S rRNA gene marker, 441 bp fragments of the hsp65 gene were used and an hsp65-related taxonomic database was constructed for the identification of Actinobacteria to the species level by Illumina-MiSeq analysis. The hsp65 marker revealed higher resolution for species and higher richness (99% operational taxonomic units cutoff) versus the 16S rRNA gene; however, more taxa were identified at higher taxonomic ranks. Actinobacteria communities varied between Mouflon and Reille caves (both pristine), and Rouffignac and Lascaux (both anthropized). Rouffignac displayed high diversity of Nocardia, suggesting human inputs, and Lascaux exhibited high Mycobacterium relative abundance, whereas Gaiellales were typical in pristine caves and the Diaclase (least affected area of Lascaux Cave). Within Lascaux, Pseudonocardiaceae dominated on unmarked walls and Streptomycetaceae (especially Streptomyces mirabilis) on marked walls, indicating a possible role in mark formation. A new taxonomic database was developed. Although not all Actinobacteria species were represented, the use of the hsp65 marker enabled species-level variations of the Actinobacteria community to be documented based on the extent of anthropogenic pressure. This approach proved effective when comparing different limestone caves or specific conditions within one cave.
- Klíčová slova
- 16S rRNA gene sequencing, Actinobacteria, Paleolithic cave, cave anthropization, hsp65 sequencing, metabarcoding,
- MeSH
- Actinobacteria * genetika MeSH
- Bacteria MeSH
- fylogeneze MeSH
- jeskyně * mikrobiologie MeSH
- lidé MeSH
- RNA ribozomální 16S genetika MeSH
- uhličitan vápenatý MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- RNA ribozomální 16S MeSH
- uhličitan vápenatý MeSH
To develop materials for drug delivery and tissue engineering and to study their efficiency with respect to ossification, it is necessary to apply physicochemical and biological analyses. The major challenge is labor-intensive data mining during synthesis and the reproducibility of the obtained data. In this work, we investigated the influence of time and temperature on the reaction yield, the reaction rate, and the size, shape, and phase of the obtained product in the completely controllable synthesis of calcium carbonate. We show that calcium carbonate particles can be synthesized in large quantities, i.e., in gram quantities, which is a substantial advantage over previously reported synthesis methods. We demonstrated that the presence of vaterite particles can dramatically stimulate hydroxyapatite (HA) production by providing the continued release of the main HA component - calcium ions - depending on the following particle parameters: size, shape, and phase. To understand the key parameters influencing the efficiency of HA production by cells, we created a predictive model by means of principal component analysis. We found that smaller particles in the vaterite state are best suited for HA growth (HA growth was 8 times greater than that in the control). We also found that the reported dependence of cell adhesion on colloidal particles can be extended to other types of particles that contain calcium ions.
- MeSH
- buňky 3T3 MeSH
- hydroxyapatity chemie metabolismus MeSH
- myši MeSH
- osteoblasty účinky léků metabolismus MeSH
- systémy cílené aplikace léků MeSH
- tkáňové inženýrství MeSH
- uhličitan vápenatý chemická syntéza chemie MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- hydroxyapatity MeSH
- uhličitan vápenatý MeSH
Magnesium isotope ratios (26Mg/24Mg) can provide insights into the origin of Mg pools and fluxes in catchments where Mg sources have distinct isotope compositions, and the direction and magnitude of Mg isotope fractionations are known. Variability in Mg isotope compositions was investigated in three small, spruce-forested catchments in the Czech Republic (Central Europe) situated along an industrial pollution gradient. The following combinations of catchment characteristics were selected for the study: low-Mg bedrock + low Mg deposition (site LYS, underlain by leucogranite); high-Mg bedrock + low Mg deposition (site PLB, underlain by serpentinite), and low-Mg bedrock + high Mg deposition (site UDL, underlain by orthogneiss). UDL, affected by spruce die-back due to acid rain, was the only investigated site where dolomite was applied to mitigate forest decline. The δ26Mg values of 10 catchment compartments were determined on pooled subsamples. At LYS, a wide range of δ26Mg values was observed across the compartments, from -3.38 ‰ (bedrock) to -2.88 ‰ (soil), -1.48% (open-area precipitation), -1.34 ‰ (throughfall), -1.19 ‰ (soil water), -0.99 ‰ (xylem), -0.95 ‰ (needles), -0.82 ‰ (bark), -0.76 ‰ (fine roots), and -0.76 ‰ (runoff). The δ26Mg values at UDL spanned 1.32 ‰ and were thus less variable, compared to LYS. Magnesium at PLB was isotopically relatively homogeneous. The δ26Mg systematics was consistent with geogenic control of runoff Mg at PLB. Mainly atmospheric/biological control of runoff Mg was indicated at UDL, and possibly also at LYS. Our sites did not exhibit the combination of low-δ26Mg runoff and high-δ26Mg weathering products (secondary clay minerals) reported from several previously studied sites. Six years after the end of liming at UDL, Mg derived from dolomite was isotopically undetectable in runoff.
- MeSH
- chemické látky znečišťující vodu chemie MeSH
- hořčík chemie izolace a purifikace MeSH
- izotopy chemie MeSH
- kyselý déšť MeSH
- látky znečišťující půdu chemie izolace a purifikace MeSH
- lidé MeSH
- monitorování životního prostředí * MeSH
- půda chemie MeSH
- stromy chemie MeSH
- uhličitan vápenatý chemie MeSH
- znečištění životního prostředí prevence a kontrola MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
- Evropa MeSH
- Názvy látek
- calcium magnesium carbonate MeSH Prohlížeč
- chemické látky znečišťující vodu MeSH
- hořčík MeSH
- izotopy MeSH
- kyselý déšť MeSH
- látky znečišťující půdu MeSH
- půda MeSH
- uhličitan vápenatý MeSH
A taxonomic study of two fluorescent Pseudomonas strains (HJ/4T and SJ/9/1T) isolated from calcite moonmilk samples obtained from two caves in the Moravian Karst in the Czech Republic was carried out. Results of initial 16S rRNA gene sequence analysis assigned both strains into the genus Pseudomonas and showed Pseudomonas yamanorum 8H1T as their closest neighbour with 99.8 and 99.7 % 16S rRNA gene similarities to strains HJ/4T and SJ/9/1T, respectively. Subsequent sequence analysis of rpoD, rpoB and gyrB housekeeping genes confirmed the highest similarity of both isolates to P. yamanorum 8H1T, but phylogeny and sequences similarities implied that they are representatives of two novel species within the genus Pseudomonas. Further study comprising whole-genome sequencing followed by average nucleotide identity and digital DNA-DNA hybridization calculations, repetitive sequence-based PCR fingerprinting with the REP and ERIC primers, automated ribotyping with the EcoRI restriction endonuclease, cellular fatty acid analysis, quinone and polar lipid characterization, and extensive biotyping confirmed clear separation of both analysed strains from the remaining Pseudomonas species and showed that they represent two novel species within the genus Pseudomonas for which the names Pseudomonas karstica sp. nov. (type strain HJ/4T=CCM 7891T=LMG 27930T) and Pseudomonas spelaei sp. nov. (type strain SJ/9/1T=CCM 7893T=LMG 27931T) are suggested.
- Klíčová slova
- Pseudomonas karstica, Pseudomonas spelaei, caves, moonmilk, sp. nov.,
- MeSH
- bakteriální geny MeSH
- DNA bakterií genetika MeSH
- fylogeneze * MeSH
- hybridizace nukleových kyselin MeSH
- jeskyně mikrobiologie MeSH
- lipidy analýza MeSH
- mastné kyseliny chemie MeSH
- Pseudomonas klasifikace MeSH
- RNA ribozomální 16S genetika MeSH
- sekvenční analýza DNA MeSH
- techniky typizace bakterií MeSH
- uhličitan vápenatý * MeSH
- zastoupení bazí MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- DNA bakterií MeSH
- lipidy MeSH
- mastné kyseliny MeSH
- RNA ribozomální 16S MeSH
- uhličitan vápenatý * MeSH
Due to the presence of toxic pollutants, soils in former military areas need remedial actions with environmentally friendly methods. Greenhouse experiments were conducted to investigate the aided phytostabilization of multi-heavy metals (HMs), i.e. Cd, Cr, Cu, Ni, Pb, Zn, in post-military soil by Festuca rubra and three mineral amendments (diatomite, dolomite and halloysite). The amendments were applied at 0 and 3.0% to each pot filled with 5 kg of polluted soil. After seven weeks of the phytostabilization, selected soil properties, biomass yield of F. rubra and immobilization of HMs by their accumulation in plant and redistribution among individual fractions in soil were determined. In addition, ecotoxicology parameters of non-amended and amended soil were established using Phytotoxkit (Sinapsis alba) and Ostracodtoxkit (Heterocypris incongruens) tests. The addition of halloysite significantly increased F. rubra biomass. Diatomite significantly increased both the Cd, Cu, Pb and Cr concentrations in the roots and the pH of the soil. The application of halloysite significantly decreased the Cd and Zn contents of the soil after the completion of the experiment. Dolomite and halloysite were more effective in HM immobilization in soil by decreasing their content in an exchangeable fraction than diatomite. These soil amendments significantly differentiated the length of S. alba roots and had a positive effect on the development of H. incongruens.
- Klíčová slova
- Ecotoxicological tests, Festuca rubra, Metal fractionation, Metal immobilization,
- MeSH
- biodegradace MeSH
- biomasa MeSH
- Festuca chemie růst a vývoj MeSH
- hořčík chemie MeSH
- jíl chemie MeSH
- kořeny rostlin růst a vývoj MeSH
- látky znečišťující půdu analýza MeSH
- půda chemie MeSH
- regenerace a remediace životního prostředí metody MeSH
- těžké kovy analýza MeSH
- uhličitan vápenatý chemie MeSH
- vojenská zařízení * MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- calcium magnesium carbonate MeSH Prohlížeč
- hořčík MeSH
- jíl MeSH
- látky znečišťující půdu MeSH
- půda MeSH
- těžké kovy MeSH
- uhličitan vápenatý MeSH
To employ dual advantages of emulsion and gel, a facile approach was investigated to fabricate core/shells structured hydrogel beads based on sodium alginate (SA) via Pickering emulsion template and in situ gelation. The encapsulation and controlled release behavior were further studied using lysozyme (Ly) as the model protein. The optical micrographs and SEM images indicated the SA beads could well disperse with the size about 150 μm. CaCO3 microparticles were strong adhesive onto SA gel. It showed that 96.51 ± 0.62% Ly was loaded into the hydrogel beads. The released behavior of Ly could be regulated by external pH condition, and displayed highest release rate at pH 5.0. Whereas the lowest release rate was recorded at pH 7.0. The released behavior well followed the Hixcon-Crowell model which indicated that the release mechanism of Ly followed the corrosion diffusion law. The worth-while endeavor provide an artful and facile approach using Pickering emulsion template and in situ gelation to fabricate core/shells structured SA beads with high load capacity and controlled regulation of the entrapped functional component.
- Klíčová slova
- Calcium carbonate, Controlled release, Gel, Lysozyme, Sodium alginate,
- MeSH
- algináty chemie MeSH
- difuze MeSH
- emulze MeSH
- hydrogely chemie MeSH
- kinetika MeSH
- koncentrace vodíkových iontů MeSH
- léky s prodlouženým účinkem * MeSH
- muramidasa chemie MeSH
- příprava léků metody MeSH
- roztoky MeSH
- uhličitan vápenatý chemie MeSH
- uvolňování léčiv MeSH
- změna skupenství MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- algináty MeSH
- emulze MeSH
- hydrogely MeSH
- léky s prodlouženým účinkem * MeSH
- muramidasa MeSH
- roztoky MeSH
- uhličitan vápenatý MeSH
