The impact of exclude factors on the transmissivity values of crystalline units of the Českomoravská vysočina

During detailed hydrogeological evaluation of crystalline units of the Českomoravská vysočina highland, the statistical analysis was used to compare variability of transmissivity in various geological units and to define its dependence on the morfological position of the hydrogeological objects. As obvious from results, the various geological units and rock types do not prove any significant difference in their prevailing transmissivity, whereas the diferrent geomorfological position does.During detailed hydrogeological evaluation of crystalline units of the Českomoravská vysočina highland, the statistical analysis was used to compare variability of transmissivity in various geological units and to define its dependence on the morfological position of the hydrogeological objects. As obvious from results, the various geological units and rock types do not prove any significant difference in their prevailing transmissivity, whereas the diferrent geomorfological position does

Hydrogeologické poměry hydrogeologického rajonu 4232 Ústecká synklinála v povodí Svitavy z hlediska tvorby podzemní vody jako zdroje vody pitné

Hydrogeological area 4232 Ústí syncline in the drainage basin of the Svitava river is producing very significant amounts of underground water. This water has been used as drinking water since 1914 for the Brno agglomeration. Two hydrogeological structures are exploited: aquifer C (Jizera formation) and aquifer B (Bílá hora formation). The Ústí syncline represents an asymmetrical graben, the deepest part of which is delineated by the Semanín and Svitava faults. The underground water of both structures is replenished by rainfall in the areas where they crop-out, namely in the eastern flank of the whole syncline. Systematical monitoring of the quality of the underground water has been running in the area for a very long time. It comprises mainly monitoring of the water quality in the individual production areas and monitoring of wells of the Czech Hydrometeorological Institute. Evaluation of all these quality of underground water monitoring data showed, that the whole area of the Ústí syncline, but especially the aquifer C, is threatened by areal pollution by nitrate compounds and locally by pesticide metabolites. Nitrate content reach up to 40 mg/l, which is the limit concentration set by the regulation 252/2004 Sb. Pesticides locally exceed the limit concentration. This shows, that the most dangerous compounds for the underground water as potential contaminants are clearly compounds closely connected with agriculture. The introduction of potential contaminants is of course controlled by the hydrogeological properties of rocks, i.e. whether it is a reservoir rock or a sealing rock. Sandstones of the aquifer C are separated by a layer of marl, sometimes called the Ca/Cb aquiclude. However, in the near-surface zone and in outcrops, this marl is heavily fractured and is very permeable. The Ústí syncline is also known by several pseudo-karst caves. Moreover, deeper pseudo-karst caverns were drilled by accident during the exploration of the Semanín fault zone. This karst permeability enables rapid spreading of infiltrating compounds including all possible pollutants. Based on tritium activity, freons and SF6 measurements, the mean delay times of the underground water in the Ústí syncline is estimated to be the first tens of years. We cannot presume any natural attenuation of very stable pesticides metabolites, just dilution. Based on this, there is a very real risk, that with increasing share of underground water younger than 2010, which have much higher concentration of pollutants, the concentration of these compounds will increase in exploited underground water

MOBILIZACE CHEMICKÝCH SLOŽEK STRUSKOVÉ DEPONIE V NÁRODNÍ PŘÍRODNÍ REZERVACI RUDICKÉ PROPADÁNÍ

The Rudice swallow hole (Rudické propadání) National Nature Monument is a locality affected by occasional mass movements and landslides. During exceptional rainfall events, the slag material from the slopes of a small valley called “Ve struskách” (“In the Slags”) slides into an episodic stream, which enters the local karst system near the swallow hole of the Jedovnice Creek (Jedovnický potok).The slag was dumped in the locality in consequence of the past processing of iron ore in blast furnaces, which had been built near Jedovnice by the princely Salm family in the 19th century. Even though the blast furnaces were closed down a hundred years ago, the slag components leaking into the Rudice stream sink cave system still demonstrably damage the speleothems. This was the majorimpulse for us to have a closer look at the geochemical properties of the slag.The chemical composition was determined by silicate analyses carried out in the Institute of Geological Sciences at the Faculty of Sciences of the Masaryk University in Brno and in the ACME laboratories in Canada. The ACME laboratories determined heavy metal contents by atomic absorption spectroscopy (AAS) and by inductively coupled plasma mass spectrometry (ICP-MS). The petrographic characterization of the slag and its enclosures was conducted based on point analyses by a wavelength dispersive X ray (WDX) electron microprobe. Predictions regarding the geochemical behavior of the slag components in an aqueous environment were made using the sequential extraction analysis (SEA) according to Tessier (1979).We have found the expected spatial variability of the basic chemical composition of the slag dumps, as well as the presence of heavy metals (cadmium and especially zinc are present at high concentrations).The slag material exhibits a glassy amorphous structure containing occasional mineral crystals, droplets of pure or oxidized iron and fragments of other materials (such as charcoal or blast furnace bricks). The ongoing weathering of the slag is accompanied by oxidation of crude iron and formation of limonite. Apart from that, the material is not subject to signifi cant secondary transformations. The results of the sequential extraction analyses of slag and soil samples suggest that Cd and Zn are chemically bound to the “carbonate fraction”, which, in general, tends to dissolve under acidic conditions. Even though the environment of the carbonate rock cave systems is typically alkaline, there is a persisting risk of mobilization of heavy metals by acid soil solutions. From the environmental point of view, the slag deposition primarily represents a source of clastic material, which contaminates the cave system and damages speleothems by mechanical abrasion

Zinc phosphate-based nanoparticles as a novel antibacterial agent: in vivo study on rats after dietary exposure

Background: Development of new nanomaterials that inhibit or kill bacteria is an important and timely research topic. For example, financial losses due to infectious diseases, such as diarrhea, are a major concern in livestock productions around the world. Antimicrobial nanoparticles (NPs) represent a promising alternative to antibiotics and may lower antibiotic use and consequently spread of antibiotic resistance traits among bacteria, including pathogens. Results: Four formulations of zinc nanoparticles (ZnA, ZnB, ZnC, and ZnD) based on phosphates with spherical (ZnA, ZnB) or irregular (ZnC, ZnD) morphology were prepared. The highest in vitro inhibitory effect of our NPs was observed against Staphylococcus aureus (inhibitory concentration values, IC50, ranged from 0.5 to 1.6mmol/L), followed by Escherichia coli (IC50 0.8-1.5mmol/L). In contrast, methicillin resistant S. aureus (IC50 1.2-4.7mmol/L) was least affected and this was similar to inhibitory patterns of commercial ZnO-based NPs and ZnO. After the successful in vitro testing, the in vivo study with rats based on dietary supplementation with zinc NPs was conducted. Four groups of rats were treated by 2,000mg Zn/kg diet of ZnA, ZnB, ZnC, and ZnD, for comparison two groups were supplemented by 2,000mg Zn/kg diet of ZnO-N and ZnO, and one group (control) was fed only by basal diet. The significantly higher (P<0.05) Zn level in liver and kidney of all treated groups was found, nevertheless ZnNPs did not greatly influence antioxidant status of rats. However, the total aerobic and coliform bacterial population in rat feces significantly decreased (P<0.05) in all zinc groups after 30d of the treatment. Furthermore, when compared to the ZnO group, ZnA and ZnC nanoparticles reduced coliforms significantly more (P<0.05). Conclusions: Our results demonstrate that phosphate-based zinc nanoparticles have the potential to act as antibiotic agents

Přírodní památky Vysokých Tater a jejich turistické využití

Import 11/06/2007Prezenční541 - Institut geologického inženýrstv

Simple method for quantification of metal-based particles in biopsy samples of patients with long bone implants – Pilot study

The presence of particles fixed in tissue samples due to implant degradation or disintegration plays an important role in post-operative complications. The ability to determine the size, shape, chemical composition and, above all, the number of these particles can be used in many areas of medicine. This study presents a novel, simple metal-based particle detection method using scanning electron microscopy with energy dispersive spectrometer (SEM-EDS). The presence of metal particles in biopsy specimens from long bone nail-fixated implants (10 patients with titanium steel nails and 10 patients with stainless steel nails) was studied. The samples were analysed using automated area analysis based on image binarization and brightness to 255 grayscale. The results were supplemented with histological data and statistically analysed. The method based on the software used was found to be accurate and easy to use and, thus, appears to be very suitable for particle detection in similar samples.Web of Science103art. no. 10428

Pretransplant BK Virus-Specific T-Cell-Mediated Immunity and Serotype Specific Antibodies May Have Utility in Identifying Patients at Risk of BK Virus-Associated Haemorrhagic Cystitis after Allogeneic HSCT

BK polyomavirus (BKPyV) persists lifelong in renal and urothelial cells with asymptomatic urinary shedding in healthy individuals. In some immunocompromised persons after transplantation of hematopoietic stem cells (HSCT), the BKPyV high-rate replication is associated with haemorrhagic cystitis (HC). We tested whether the status of BKPyV immunity prior to HSCT could provide evidence for the BKPyV tendency to reactivate. We have shown that measurement of pretransplant anti-BKPyV 1 and 4 IgG levels can be used to evaluate the HC risk. Patients with anti-BKPyV IgG in the range of the 1st–2nd quartile of positive values and with positive clinical risk markers have a significantly increased HC risk, in comparison to the reference group of patients with “non-reactive” anti-BKPyV IgG levels and with low clinical risk (LCR) (p = 0.0009). The predictive value of pretransplant BKPyV-specific IgG was confirmed by determination of genotypes of the shed virus. A positive predictive value was also found for pretransplant T-cell immunity to the BKPyV antigen VP1 because the magnitude of IFN-γ T-cell response inversely correlated with posttransplant DNAuria and with HC. Our novel data suggest that specific T-cells control BKPyV latency before HSCT, and in this way may influence BKPyV reactivation after HSCT. Our study has shown that prediction using a combination of clinical and immunological pretransplant risk factors can help early identification of HSCT recipients at high risk of BKPyV disease