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Mechanical properties of marine sediment near Koper and numerical modelling of a deep excavation
Tůma, Pavel ; Mašín, David (advisor) ; Miča, Lumír (referee)
Mechanical properties of marine sediment near Koper and numerical modelling of a deep excavation Engineering geological conditions near the port Koper in southwestern Slovenia forces geotechnical experts and civil engineers to solve problems in foundation various types of objects and purpose of the practice since the fifties of last century, when it began an intensive development of infrastructure of the port. The results of series of geological and geotechnical surveys, monitoring, and long experience with foundation in the local geology shows that it is almost always the 3rd geotechnical category, or foundation of complex structures in difficult geological conditions below the water table. The entire area belongs to Alpine-Dinaric tectonic area. The rock foundation is composed of complexes of flysch sediments Eocene age at which mounted files of recent marine sediments in the area widely submerged river valley fluvial sands and gravels. From the geotechnical point of view it is interesting site, where most buildings were based on a layer of soft marine sediments, where it is through the creation of special methods implemented in the establishment of deep-level endurable layers of gravel and sand of the river Rižana or at the level footingwall flysch. Set of marine sediments near the port Koper,...
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Activity of new nickel-complexes in coupling reactions
Plaček, Martin ; Svoboda, Jan (advisor) ; Hoškovec, Michal (referee)
In this work, we report the study of the catalytic activity of newly prepared coordination compounds of nickel(II) (complexes were prepared by prof. Kyritsis, University of Athens). The activities in model reactions of Kumada and Suzuki coupling and polymerization of 2,5- dibromo-3-hexylthiophene were tested. For Kumada coupling, the activity is comparable with known complex [Ni(dppp)Cl2]. On the other hand, selected complexes exhibit only limited activity for Suzuki coupling. GRIM polymerization of 2,5-dibromo-3-hexylthiophene was successful. Properties of prepared polymers are comparable with polymers prepared via known route with [Ni(dppp)Cl2].
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Effect of hydrogen sulphide on aging of porcine oocytes in vitro
Krejčová, Tereza ; Petr, Jaroslav (advisor) ; Ješeta, Michal (referee)
Unfertilized or parthenogenetically non-activated porcine oocytes matured in vitro conditions are subjected to a process known as aging. During such development, porcine oocytes undergo the complex of the structural and functional changes, which can result in spontaneous parthenogenetic activation, fragmentation or lysis. After three days of culture in our condition, 23% of oocytes remained at the stage of metaphase II, 48% of oocytes were spontaneously parthenogenetically activated, 26% of oocytes were subjected to fragmentation and 3% of oocytes were lysed. The complete suppression of porcine oocyte fragmentation during the process of aging occurred during oocytes cultured in medium with sulphide donor Na2S in concentrations 150 µM and 300 µM. Inhibition of enzymes catalyzing the synthesis of hydrogen sulfide in the oocytes during the process of aging (cystathionine-gamma-lyase and cystathionine beta-synthase), iniciates earlier onset of oocytes fragmentation. The effect of both inhibitors could be completely reversed by using sulphide donor Na2S. The process of aging in porcine oocytes significantly reduces the success of the activation processes. Parthenogenetic activation occurred in 94% of pig oocytes, which were not subjected to aging. The proportion of activated oocytes after exposure to 24...
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Cropping management influence on epigeic arthropods´ biodiversity
Michalčíková, Lenka ; Barták, Miroslav (advisor)
Soil biota is critical for many functions Agro Ecosystems, provides various ecosystem services. Has an impact on the water regime of soil, detoxify contaminants like. These processes (and organisms that control) determines plant growth and thus maintain long-term productivity of ecosystems Agro. Soil also hosts many invertebrate herbivores, microbial pathogens and rhizosphere organisms that have a direct impact on the growth of crops. Modi fi cation of vegetation and soil themselves agricultural activities affect soil biota, which has retroactive effect on plant growth and nutrient turnover. Indirect influence of soil biota in agriculture lies in the manipulation of plant cover, which affects the quality and quantity of organic inputs to the soil (Bartak, 2002). Just as property of the soil by soil organisms, employee participation, and vice versa soil organisms react sensitively to any changes of soil environment (Barrios, 2007).
This view of individual species allows us to analyze the composition of Agro biota. For many systematic groups agrobiocenóza formed predominantly species of group 2, thus representing a degradation stage agrobiocenóza original cenózy in other taxa in turn is substantially represented group 3. Specific agrobiocenózy composition also depends on the type of culture and forms management (Barták 2002).
Traditional technology tillage. Basic tillage involves plowing, plowing, and their treatment, deepening topsoil, undermining and deep soil loosening. Tillage to regulate the conditions for plant growth and development. Further modifying the physical state of the ground, regulates the ratio between water and air in the soil, acts on the activity of microorganisms and invertebrates; tillage accelerates mineralization of organic substances affects Humicola fi cation processes in the soil. The level of tillage is strongly reflected in the development of plants during all vegetation (Faměra, 1993). According Suškeviče (1997) is essential in conventional agriculture obdělávacím surgery and one of the most important measures agrotechnical plowing. Minimizing tillage systems Reducing tillage intensity, ie. Minimization system and direct the mean substantial benefits for soil fertility. The intensity of tillage has a big impact on her fertility and maturity. Such as soil fertility is understood its long-term ability to procreate, while the maturity of the soil is a measure of soil structure supporting the right fertility. The key indicators of soil fertility are the aggregation of soil particles (density, clay and humus complexes), porosity and water content and soil nutrients. The high humus content, high biological activity and low erosion are the determining factors behind the high fertility of the soil. Minimization and soil conservation systems, these factors promote (Köller and Linke, 2006).
Many previous studies comparing the biodiversity of farmland under different management systems. These studies cover a wide range of taxa. Hole et al. (2005) 76 worthy of such studies. Regarding cultivation practices, there is work comparing biodiversity much less. For example Schier (2006) considers the soil conservation tillage of the soil behind friendly environment which is favorable for arthropods, particularly insects.
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Phosphates containing food and their implications for osteoporosis
Šobáň, Jan ; Rambousková, Jolana (advisor) ; Černá, Milena (referee)
Phosphates containing food and their implications for osteoporosis Phosphates are salts of phosphoric acid resulting from the secession of three acidic hydrogen from it. Phosphates are found in natural foods such as nuts, legumes, cereals, meat and offal. Phosphorus is also being added to foods industrially for its' various chemical properties. From more than 1 500 "E's" I found 16 that contain phosphates and thus significantly increase the supply of phosphorus in the body. Usual daily intake of phosphorus is about 1 g. Increased intake of phosphorus forms an acidic environment in the kidney and calcium phosphate complexes, and thus leads to calcium removing from the body and bone demineralization. "E's" containing phosphates are frequently found in meat products, processed cheese, confectionery, bakery products, cola beverages, frozen and instant foods. Most commonly used additive is E-338 phosphoric acid. Osteoporosis is a systemic skeletal disease characterized by a small amount of bone mass and de- terioration of bone micro-architecture resulting in increased fragility and fracture risk. The Czech Republic declares to have 600 000 patients treated for osteoporosis.
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Macrocyclic chelators for metal-radionuclides
Málková, Michaela ; Hermann, Petr (advisor) ; Příhoda, Jiří (referee) ; Komárek, Pavel (referee)
5 Abstract in English Complexation properties of structurally related macrocyclic polyazachelators with different metal ions suitable for a medicinal use were studied. In the present work, a study of chelators formally derived from H4dota (1,4,7,10-tetraazacyclododecane-1,4,7,10- tetraacetic acid) by replacement of one or four carboxylic groups with a phosphorus acid moiety(ies) was performed. Three new chelators were studied: H4do3apABn (10-{[(4-aminobenzyl)hydroxyphosphoryl]methyl}- 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid), H5do3apPrA (10-{[(2-carboxyethyl)hydroxyphosphoryl]methyl}- 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid), H4dotpOEt [1,4,7,10-tetraazacyclododecane-1,4,7,10- tetrakis(methylphosphonic acid monoethylester)] In addition new data on stability constants of transition metal complexes of H5do3ap, 10-[(dihydroxyphosphoryl)methyl]- 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid, are presented. The achieved results suggest that all studied chelators form complexes with di- and trivalent metal ions with sufficient thermodynamic stability and kinetic inertness for the potential medicinal applications. The formation rate of complexes of the monophosphonic/inic chelators is comparable to that of the H4dota complexes. The formation rate of the complexes depends highly on...
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The Influence of eco-toxicological factors on spermatogenesis, morphology and function of mammalian sperm
Vašinová, Jitka ; Pěknicová, Jana (referee) ; Hortová, Kateřina (advisor)
An increasing infertility due to pathological changes on sperm has become a serious issue. A rising concentration of fluorides in the environment could be a potentially negative factor affecting the male fertility. Eco-toxicological effect of fluorides can be enhanced in the present of aluminium ions by forming fluoro-metallic complexes, analogues of phosphate groups that interfere with the activity of G-proteins and P-type ATPases, which are part of several signalling pathways during sperm maturation. The aim of this thesis was monitoring the effect of fluorides on mouse sperm capacitation in vitro, analysis of the effect of fluorides on male reproductive organ and on the level of mouse spermatogenesis. Fluorides were administered to mice through table water at the concentrations of 0, 1, 10, 100 ppm and at the same time we monitored their synergic action with aluminium at 10 ppm dose. The level of tyrosine phosphorylation in the sperm head was the main marker for successful capacitation in vitro. The results show that an oversized load of ions, to which mice were exposed, affected negatively spermatogenesis and ability of sperm to capacitate in vitro. Besides that, a multigenerational study in mice demonstrated that even low concentrations of aluminium fluorides can have a negative effect on...
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