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Comparison of point abundance and sampling methods for 0+ fish
Janáč, M. ; Jurajda, Pavel
We compared structure of 0+fish assemblages estimates given by two different sample strategies: point abundance sampling (PAS) and continual sample method (CS). No statistital significant difference was found betweem both strategies in number of species, dominance and indices of diversity. CS is more time consuming sampling strategy.
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Surface relief evolution in cast superalloy In738LC fatigued at room temperature
Samek, Petr ; Obrtlík, Karel (referee) ; Juliš, Martin (advisor)
Low cycle fatigue is an important valving parameter of materiale which are exposed random alternate strain during their operation. The alternate strain in that material is caused by temperature fluctuations during operation and outages such as aircraft engines. Tests of low cycle fatigue were performed on samples of superalloy Inconel 738LC at stable room temperature at 23°C. The actual experiment took place at certain intervals, consisting of cycling itself, and observing changes in surface relief by light and electron microscopy. There was observed significant surface relief at an early stage of low cycle fatigue. We compared results of measurement with other different observation methods.
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The solid depozited precipitation in the small catchments in the Czech Republic
Fišák, Jaroslav ; Tesař, Miroslav
The samples were collected in two localities differing in the industrial pollutant load. The first locality situated in the Sumava Mts. represents a relatively clean region of the Czech Republic. The second locality is situated in the Northern Bohemia. This locality is represented by the Milesovka Observatory of the IAP ASCR. The region is heavy polluted by the industrial load in this case. The one-shot sample collection in the Sumava Mts. at 28 localities was made on January 4th, 1990. There were shown: i) The ion concentrations in the rime water depend on the industrial load of the region and on the local pollutant sources; ii) The local pollutant sources play the main role in ion concentrations in rime water; iii) The ion concentrations decrease with altitude.
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Comparison of chemical composition of throughfall and deposited precipitation
Chaloupecký, Pavel ; Špičková, Jitka ; Fišák, Jaroslav ; Skřivan, Petr
Since June 2004 throughfall samples in beech and spruce vegetation have been taken at the observatory Milesovka. Ever since 1998 fog water samples have been taken there as well. In this paper are compared the concentrations of main ions and trace elements in throughfall and in deposited precipitation. The concentrations of main ions and trace elements in throughfal are primarily affected by the volume of samples. The highest concentrations of monitored sustances in throughfall were recorded in September and in October when the lowest rainfall totals were measured. The concentrations of monitored sustances were in throughfall mostly higher in spruce vegetation in comparison with beech vegetation. It is probably due to the thicker treetop in spruce vegetation on Milesovka observatory. Due to the thicker treetop a smaller volume of throughfall is let fall and the substances from ambient air are captured more effectively in comparison with beech vegetation. In the case of main ions the lowest concentrations were measured in fog water samples. For trace elements wasn´t data. From comparison with reference locality Lesni potok is obvious that concentrations of monitored sustances in throughfall on Milesovka exceed sharply concentrations in locality Lesni potok. This difference is considerably higher by spruce vegetation in comparison to beech vegetation which indicate that it is necessary take not only local air quality into account but also type of vegetation and thick of treetop which can very significantly contribute to the chemical composition of throughfall.
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Effects of nitrogen supply and drought on wheat grain quality under the ambient and elevated concentrations of carbon dioxide
Moravcová, Gabriela ; Vránová, Dana (referee) ; Hrstka, Miroslav (advisor)
This diploma thesis deals with effects of nitrogen supply, drought and UV radiation on wheat grain quality under the ambient and elevated concentrations of carbon dioxide. The theoretical part deals with the global climate changes, greenhouse gases and especially with effects of elevated concentrations of carbon dioxide on plants. Also, it is dealt with effects of elevated concentrations of carbon dioxide on the wheat grain quality. In the experimental part nitrogen content by the Kjeldahl method, contents of dry and wet gluten, Zeleny test, falling number and content of starch in the wheat samples were determined. The results of this study confirmed affecting the quality of the wheat grain from the elevated concentrations of CO2, nitrogen fertilization, drought and UV radiation. The most evident was the influence of nitrogen nutrition, fertilization positively affected the quality of grain, there was an increase in content of crude protein, gluten content, value of Zeleny sedimentation test, and falling number. As a result of the increase in protein content was also a decrease in starch content. Due to increased levels of carbon dioxide protein content and gluten, Zeleny sedimentation test values and falling number decreased and conversely starch content increased. The decrease of Zeleny sedimentation test by the influence of elevated CO2 concentration was fully compensated by nitrogen fertilization.
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Assessment of aroma active compounds in elderberries
Kaňová, Kateřina ; Divišová, Radka (referee) ; Vítová, Eva (advisor)
This work is focused on determination of aroma compounds of elderberries (Sambucus nigra L.). The theoretical part provides an overview of the properties, occurrence, other varieties and composition of elder berries and their use particular in the production of juices. The possibilities of assessment of aroma compounds are also briefly discussed. In the experimental part, the identification and quantification of aroma compounds in samples of mixed juices (elder with grape) and comparison of the content of aroma compounds in different types of juices, was made. Solid Phase Microextraction in conjunction with gas chromatography (SPME-GC) was used for analysis. Totally 51 different volatile aroma compounds were identified. They were 19 alcohols, 10 aldehydes, 8 esters, 7 ketones, 6 fatty acids and an oxide. As expected, the largest amount of aroma compounds was found in sample of pure elderberry juice.
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Stress-strain analysis of arterial aneurysms
Tesařová, Petra ; Skácel, Pavel (referee) ; Burša, Jiří (advisor)
The diploma thesis is focused on the creation of the aneurysm finite element model and the making of the aneurysm wall stess-strain analysis using ANSYS software. The model of abdominal aortic aneurysm geometry starts from the CT scan of the particular patient. In the thesis there are compared two chosen constitutive models, each of them appears from different mechanical tests done on human arterial fibre samples. Furthermore, a limiting condition for aneurysm wall structure damage is expressed. On the basis of the results of stress calculation in the aneurysm wall and the limiting condition, the safety coefficient and rupture factors risk are worked out.
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Detection and characterization of hepatocellular liver lesions by using MRI with hepatospecific contrast agent Gd-EOB-DTPA
Mrklovský, Milan ; Žižka, Jan (advisor) ; Mechl, Marek (referee) ; Ferda, Jiří (referee)
Detection and characterization of hepatocellular liver lesions by using MRI with hepatospecific contrast agent Gd-EOB-DTPA Aim: To prospectively compare contrast properties of extracelullar (gadobutrol) and hepatospecific (gadoxetic acid) contrast agents in upper abdominal MRI studies. To prospectively evaluate the possibilities of detection and characterization of hepatocellular liver lesions by means of MRI using hepatospecific contrast agent Gd-EOB-DTPA. Materials and methods: Standardized (0,1 ml/kg) dose of gadobutrol (56 subjects) and gadoxetic acid (51 subjects) was administered intravenously by MRI-compatible injector at 2 ml/s, followed by 20 ml saline flush. MR signal intensity changes (SIC) between precontrast scans and arterial phase, portal venous phase, equilibrium, and delayed scans at 10 and 20 minutes were measured in abdominal aorta, portal vein, common bile duct, liver, and spleen. Mean SIC values for gadobutrol and gadoxetic acid were compared by a two-sample t-test with p-value < 0,05 considered significant. A total of 78 subjects with known arterial hypervascularized liver lesion (other than haemangioma) were examined on MRI with administration of liver specific contrast agent Gd-EOB-DTPA. All studies were performed before and after contrast agent injection in arterial, portal...
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Characterization of FRET sensor
Datinská, Vladimíra ; Klepárník, Karel ; Belšánová, B. ; Minárik, M. ; Foret, František
In this study, we present characterization of sensor based on Fӧrster resonance energy\ntransfer (FRET). The sensor is composed of ssDNA chain attached to a laboratory\nsynthesized quantum dot (QD). A complementary chain of a sample is labeled by a\nluminescent dye. When the dsDNA hybrid is formed, the energy from the QD (donor)\nis transferred to the dye (acceptor) and FRET is observed as a decrease of QD\nluminescence emission intensity and an increase of dye luminescence emission\nintensity.
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