National Repository of Grey Literature 117 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Examination of the polymorphism of the gene ApoE
Alzheimer´s disease (AD) belongs to the most frequent cause of dementia in the world. It is determined that it is about 65-75 % of all the dementias (Preiss, Přikryková Kučerová, 2006). The term Alzheimer Dementia, as well as Pre-senile Form (AD) is used with the patients at the age up to 65 years (Seidl, 2015). After the age of 65 years we use the term Senile Dementia of the Alzheimer Type. (SDAT). Up to the age of 45 this desease is rare (Seidl, Obenberger, 2004). Causal treatment of this disease does not exist, because etiopathogenesis of the disease is not entirely clarified (Seidl, 2015). The aim of this bachelor´s work was to write a professional search to the given topic. In this theoretical part there is summed up the information about neurodegenerative disease, about dementia and (AD). Most importantly there are described the symptoms, the causes, phase, treatment, diagnostics and genetic disposition of AD. The description of polymerase chain reaction (PCR) and reverse hybridization on strips is also an important part of this theoretical part. In the practical part, the main goal was to master molecular biological methods. To achieve the goals and to get the best results, I chose two methods. In addition to optimizing the PCR ARMS method, reverse hybridization was used on strips. The above-mentioned second method was performed using the commercially available ApoE StripAssay? kit from ViennaLab. In this part of the paper are described all the procedures by which I achieved the results. Molecular biological methods were performed in a laboratory at the Health and Social Faculty of the University of South Bohemia in České Budějovice.
Precipitation nowcasting for the warm part of the year
Mejsnar, Jan ; Sokol, Zbyněk (advisor) ; Jaňour, Zbyněk (referee) ; Žák, Michal (referee)
Current precipitation nowcasting systems primarily use the extrapolation of observed radar reflectivity. I used the extrapolation and studied limits of the forecast using the concept of the decorrelation time (DCT). I used data from two radars covering the territory of the Czech Republic from warm parts of four years and calculated DCT in dependence on several selected conditions describing the state of the atmosphere. I found that the mean DCT for the extrapolation is 45.4 minutes. On average the increase of the DCT in comparison when the persistence forecast is employed is 13.4 minutes. However, in dependence on current conditions the DCT may increase or decrease in more than 40 %. I also explored time evolution of the DCT during two storm events. I found that the DCT may significantly change in time, which is the consequence of changing character of the atmosphere during the storm development.
Influence of heat treatment on deformation behaviour of wrought Mg-Zn-based alloys
Olejňák, Juraj ; Drozdenko, Daria (advisor) ; Mathis, Kristián (referee)
Title: Influence of heat treatment on deformation behaviour of wrought Mg-Zn alloys Author: Juraj Olejňák Department: Department of Physics of Materials Supervisor: RNDr. Mgr. Daria Drozdenko, Ph.D. Abstract: The aim of the present thesis is to understand an influence of heat treatment on microstructure and mechanical properties of extruded Mg-Zn based alloys containing an addition of Ca and Nd. Microstructural analysis provided by electron microscopy gave us information about homogeneity and distribution of precipitates in investigated Mg alloys after extrusion and a subsequent heat treatment. Microhardness and compression test along the extrusion direction have been performed to determine optimal aging conditions for achieving better mechanical properties, such as hardness and strength. The acoustic emmision technique was used to follow active deformation mechanisms during plastic deformation. Application of the acquired knowledge in material research can contribute to design novel Mg alloys with enhanced mechanical properties for specific applications. Keywords: magnesium alloys, isothermal aging, precipitation, mechanical properties
Mechanical properties of pre-compressed Mg-Zn-Ca alloy
Hegedüs, Marius ; Dobroň, Patrik (advisor) ; Lukáč, Pavel (referee)
In wrought Mg alloys, their hexagonal closed packed structure together with a pronounced basal texture lead to anisotropy of mechanical properties. This bachelor thesis is focused on understanding the influence of previous deformation with further relaxation and/or additional heat treatment on deformation behaviour of the extruded Mg-Zn-Ca alloy. The significant influence of twins formed after pre-compression on mechanical properties was investigated. Evolution of microstructure, especially a formation of twins, is observed by light and scanning electron microscopy. The acoustic emission technique is used to determine active deformation mechanisms: dislocation slip and twinning. The results can be used for developing Mg alloys with enhanced properties.
Changes of microclimate in a sedge-grass marsh within the last 40 years
Dušek, Jiří ; Stellner, Stanislav ; Hudecová, S.
The average, maximum and minimum air temperatures have been gradually increasing since 1977 to 2017. The air temperature rise was not the same in all periods of the year. We found different increases for individual months. The daily mean air temperature rose significantly in the growing period (April-August). The precipitation characteristics have been changing in the sedge-grass marsh too. The observed trends differ among months in sign as well as in the magnitude, and they are consistent with the air temperature changes. We found that extreme precipitation seems to occur significantly more frequently in recent years compared to the period before 2000. Awareness of these changes is important for possible positive human intervention when a desirable wetland ekosystem function is threatened.\n
High entropy alloys fabricated via SPS compaction of high energy milled feedstock powders
Gubán, Ivan ; Hadraba, Hynek (referee) ; Čížek, Jan (advisor)
The subject of this thesis is preparation of CoCrFeMnNiNx high entropy mixtures via the methods of mechanical alloying and spark plasma sintering (SPS). Three series of specimens were fabricated in this thesis: samples milled in argon (benchmark materials), samples milled in nitrogen atmosphere (to observe their ability of nitrogen absorption) and samples microalloyed with CrN, FeN nitrides (to observe their dissociation into the solid solution potential). The fabricated powders and SPS compacts were subsequently observed by electron microscopy and their phase content by X-Ray diffraction (XRD) and elemental composition by EDS analysis were carried out. A method of reduction melting in inert atmosphere was used to determine the exact oxygen and nitrogen content in powders, while the respective particle size distribution measured by laser diffraction method. The influence of nitrogen content on the hardness of the samples was studied via the microhardness measured. After completing the process of mechanical alloying under the Nitrogen atmosphere was the maximal concentration of nitrogen in the structure 0,208% after 24 hours of milling (dependency on time was linear), which means, the method of milling under the Nitrogen atmosphere was successful. XRD of milled samples showed the existence of the only FCC single solid solution phase, while samples milled under the Nitrogen atmosphere showed the trend of the growth of the lattice parameter with the increasing nitrogen content. There was observed the presence of the chromium nitrides precipitates on the grain boundaries of the FCC phase in microalloyed samples. All specimen were contaminated by a mixture of metallic oxides and manganeese sulphides, which were present in the default manganeese powder. The greatest value of microhardness showed the duplex sample. The increase in values of microhardness (344 HV 0,3) in comparison with the standard sample (262,9 HV 0,3) was recorded on the samples milled under the nitrogen atmosphere, which conforms the positive influence of the nitrogen content on strength characteristics of this alloy.
Foliar application of zinc reduces the risk of drought stress on poppy (Papaver somniferum L.)
Škarpa, P. ; Richter, R. ; Hlavinka, Petr ; Trnka, Miroslav
Especially in arid regions, drought stress is considered as one of the main reasons for yield reduction of plant. Zinc, as one of the essential microelements in crop plant, plays a crucial role in resistance to drought stress. The objective of the vegetation experiment established in 2011-2015 on locality Zaboice was to explore the effect of the foliar zinc application on the yield of poppy in interactions with weather conditions observed years. Effect of zinc foliar application was significantly dependent on the average daily air temperature (r =-0.936). Foliar application of zinc increases production of poppy seed, in the range from 6.9 to 25.5 % and the efficiency of zinc foliar fertilization increases with a widening deficit rainfall calculated as the difference between the precipitation sum and reference evapotranspiration of poppy growing season (r =-0.9072). In general, the results of the present study indicate that usage of zinc foliar application reduces the harmful effects of water deficit stress and increases resistance to drought stress in poppy plant.
Proposal for adaptation measures to eliminate the climate drought
Šmaus, Petr ; Sobotková, Veronika (referee) ; Dumbrovský, Miroslav (advisor)
The aim of the thesis was to propose adaptation measures in the locality to eliminate climate drought. Additionally, the work on the proposed adaptation measures has been assessed in terms of their effectiveness and evaluation of their design. The part and contribution of the work is also to inform about problems related to climatic drought, finding their causes and subsequent.
Influence of Climatic Factor for Landslides Formation
Olejár, Filip ; Novotný, Jan (advisor) ; Kudrna, Zdeněk (referee)
TITLE INFLUENCE OF CLIMATIC FACTOR FOR LANDSLIDES FORMATION ABSTRACT Slope movements are divided into several groups, either by speed, method of movement or by factors causing their formation. The climate conditions of different territories are one of the main reasons that significantly affect the formation of slope movements. The most important climate factor that causes slope movements is precipitation. However, the effect of freezing soil can also be included here because water in the soil changes its volume and after thawing changing geomechanical properties of the material. In this work, the impact of precipitation will be discussed as the most significant climatic factor that induces breaking of the slopes. Rainwater can either gradually infiltrate into the slope, or can infiltrate in the single event with a high amount of rainfall, until it reaches a critical stage during which the weight of watered zone together with pore pressure are being increased whereas the effective shear strength is being reduced. This causes subsequent disintegration of the slope and movement of material along the slip surface in case of sliding movements and along the native surface in case of debris flows. This work summarizes the available knowledge about the precipitation as a significant factor which affects the...

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